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Dissertations / Theses on the topic 'Hsp90 gene'

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Published: 6 September 2023

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1

Smith, David. "Hsp90 and hsp70 genes of Theileria annulata : structure, regulation and molecular phylogeny." Thesis, University of York, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298437.

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2

Weeks, Stacey. "Characterisation of the HSP70-HSP90 organising protein gene and its link to cancer." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/56006.

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HOP (Heat shock protein 70/ Heat shock protein 90 organising protein) is a co-chaperone essential for client protein transfer from HSP70 to HSP90 within the HSP90 chaperone machine and has been found to be up-regulated in various cancers. However, minimal in vitro information can be found on the regulation of HOP expression. The aim of this study was to analyse the HOP gene structure across known orthologues, identify and characterise the HOP promoter, and identify the regulatory mechanisms influencing the expression of HOP in cancer. We hypothesized that the expression of HOP in cancer cells is likely regulated by oncogenic signalling pathways linked to cis-elements within the HOP promoter. An initial study of the evolution of the HOP gene speciation was performed across identified orthologues using Mega5.2. The evolutionary pathway of the HOP gene was traced from the unicellular organisms to fish, to amphibian and then to land mammal. The synteny across the orthologues was identified and the co-expression profile of HOP analysed. We identified the putative promoter region for HOP in silico and in vitro. Luciferase reporter assays were utilized to demonstrate promoter activity of the upstream region in vitro. Bioinformatic analysis of the active promoter region identified a large CpG island and a range of putative cis-elements. Many of the cis-elements interact with transcription factors which are activated by oncogenic pathways. We therefore tested the regulation of HOP levels by rat sarcoma viral oncogene homologue (RAS). Cancer cell lines were transfected with mutated RAS to observe the effect of constitutively active RAS expression on the production of HOP using qRT-PCR and Western Blot analyses. Additionally, inhibitors of the RAS signalling pathway were utilised to confirm the regulatory effect of mutated RAS on HOP expression. In cancer cell lines containing mutated RAS (Hs578T), HOP was up-regulated via a mechanism involving the MAPK signalling pathway and the ETS-1 and C/EBPβ cis-elements within the HOP promoter. These findings suggest for the first time that Hop expression in cancer may be regulated by RAS activation of the HOP promoter. Additionally, this study allowed us to determine the murine system to be the most suited genetic model organism with which to study the function of human HOP.
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3

Silva, Luciana Pugliese da. "Estudo da expressão dos genes de choque térmico hsp90, hsp60 e hsp10 do fungo aquático Blastocladiella emersonii." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-14052018-120842/.

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A proteína de choque térmico Hsp90 é uma chaperone molecular encontrada no citosol. O cDNA incompleto desta proteína foi isolado de uma biblioteca construída a partir de mRNA de células de esporulação de B. emersonii submetidas a choque térmico. Um clone genômico contendo a seqüência completa do gene hsp90 também foi isolado, seqüenciado e caracterizado. A região codificadora do gene hsp90 é interrompida por um único íntron de 184 nucleotídeos. A seqüência de aminoácidos deduzida indicou uma proteína de 71 O resíduos, com massa molecular calculada de 80.792 Da e um pl médio de 4,85. Experimentos de extensão de oligonucleotídeo e RACE-PCR demonstraram um sítio único de início de transcrição localizado a -65 e -70 nucleotídeos do ATG da metionina iniciadora, respectivamente. Motivos similares ao consenso do elemento de choque térmico eucariótico (HSE) e do elemento responsivo a estresse (STRE) foram encontrados na região promotora do gene a -395 e -98 nucleotídeos do ATG, respectivamente. Experimentos de \"Northern blot\" revelaram que o mRNA para a Hsp90 apresenta níveis máximos aos 90 minutos da fase de esporulação do fungo. Análise por \"western blot\" mostrou que a proteína Hsp90 está presente durante todo o ciclo de vida do fungo e os níveis máximos de acúmulo foram observados aos 90 minutos da esporulação, indicando um controle transcricional do gene. Tanto a proteína quanto o mRNA são altamente induzidos quando as células são submetidas a choque térmico e a cádmio. As proteínas Hsp60 e Hsp10 são chaperones moleculares mitocondriais (chaperoninas). Os cDNAs completos destas proteínas foram isolados e totalmente seqüenciados. A seqüência de aminoácidos deduzida da Hsp60 corresponde a uma proteína de 559 resíduos, com massa molecular calculada em 58.741 Da e um pl médio de 8, 7. Experimentos de \"Northern blot\" revelaram que o mRNA para Hsp60 tem níveis máximos de expressão aos 90 minutos da esporulação. Análise por \"western blot\" mostrou que a Hsp60 está presente durante todo o ciclo de vida do fungo, com níveis máximos da proteína 90 minutos após a indução da esporulação. Tanto a proteína quanto o mRNA são bastante induzidos quando as células são submetidas ao choque térmico. A seqüência de aminoácidos deduzida da Hsp10 corresponde um polipeptídeo de 101 resíduos com massa molecular calculada em 10.688 Da e um pl médio de 6,25. Experimentos de \"Northern blot\" revelaram que o mRNA para Hsp10 tem níveis máximos de expressão aos 120 minutos da germinação e é bastante induzido quando as células são submetidas ao choque térmico.
The heat shock protein 90 (Hsp90) is a cytosolic molecular chaperone. The incomplete cDNA of this protein was isolated by immunoblot screening of a heat shock cDNA expression library. The complete genomic clone was also isolated and completely sequenced and characterized. The coding sequence is interrupted by a single intron with 184 nucleotides. The deduced amino acid sequence corresponds to a 710-residue polypeptide with a calculated molecular mass of 80,792 Da and an average pl of 4.85. Primer extension and RACE-PCR experiments demonstrated a single transcription start site localized -65 and -70 nucleotides from de ATG of the initiator methionine, respectively. Sequence motifs resembling the standard eukaryotic heat shock element (HSE) and the stress responsive element (STRE) were evident in the regulatory region -395 and -98 nucleotides from de ATG, respectively. Northern blot analysis revealed that the Hsp90 mRNA presents maximum levels by 90 minutes of the sporulation stage. Immunoblot analysis indicated that the Hsp90 is present during the entire life cycle of the fungus and maximum levels were observed 90 minutes after the induction of sporulation, indicating a transcriptional control. During heat shock both the mRNA and the Hsp90 protein are highly induced. Proteins Hsp60 and Hsp10, are mitochondrial molecular chaperones (chaperonines). The complete cDNAs encoding these proteins were and completely sequenced. The deduced amino acid sequence for Hsp60 corresponds to a 559-residue polypeptide with a calculated molecular mass of 58,741 Da and an average pl of 8.7. Immunoblot analysis showed that Hsp60 is present during the entire life cycle of the fungus and presents maximum levels by 90 minutes of the sporulation. Northern blot analysis indicated maximum levels of the Hsp60 mRNA by 90 minutes of sporulation too. Both mRNA and the protein are highly induced during heat shock. The deduced amino acid sequence for Hsp10 corresponds to a 101-residue polypeptide with a calculated molecular mass of 10,688 Da and an average pl of 6.25. Northern blot analysis indicated maximum mRNA levels by 120 minutes of germination and high levels of expression when the cells are exposed to heat shock.
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4

Mattison, Stacey. "Analysis of the human HSP70-HSP90 organising protein (HOP) gene - characterisation of the promoter and identification of a novel isoform." Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/62821.

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5

Hu, Bin. "Functional analysis of the middle domain of Hsp90, and characterisation of QR12/NSE4, an essential cell cycle gene that is found in an Hsp90 complex." Thesis, King's College London (University of London), 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424460.

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6

Sass, Jennifer Beth. "Heat-inducible and constitutive expression of the 90 kD heat shock protein gene, Hsp90, during zebrafish embryogenesis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ32798.pdf.

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7

Marsee, Derek K. "Exploration of novel therapies for thyroid cancer adenoviral gene therapy and 17-allylamino-17-demethoxygeldanamycin /." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1087497053.

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Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xv, 118 p.; also includes graphics (some col.) Includes bibliographical references (p. 106-118). Available online via OhioLINK's ETD Center
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8

Jacob, Tiago Rinaldi. "Expressão, regulação e funcionalidade de genes HSPs no dermatófito Trichophyton rubrum." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-15052014-105536/.

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O dermatófito Trichophyton rubrum é um fungo filamentoso, queratinofílico e antropofílico, sendo o principal agente etiológico de micoses cutâneas em humanos. Sua distribuição cosmopolita e seu acometimento grave em pacientes imunocomprometidos fazem dele um dos desafios a ser enfrentado pelos serviços de saúde pública mundial. As interações patógeno-hospedeiro envolvem diferentes processos relacionados com a degradação de queratina e com modificações metabólicas que permitem sua adesão e posterior penetração nos tecidos infectados. Essas alterações são importantes para o sucesso do processo infeccioso e envolvem mecanismos que modulam a expressão gênica, a secreção de proteínas específicas, a adaptação metabólica e as alterações no pH cutâneo, fundamentais para o estabelecimento da infecção. Dentre as proteínas que participam do processo de interação patógeno-hospedeiro estão as proteínas de choque térmico HSPs (Heat Shock Proteins), relacionadas aos mais diversificados processos celulares. Nesse sentido, a hipótese desse trabalho foi avaliar se os genes hsps de T. rubrum, bem como seu principal fator de transcrição (Hsf1), estão envolvidos nos processos de resposta a situações adversas e na interação com o microambiente hospedeiro, e se estes genes são modulados pelo fator de transcrição pacC, um regulador envolvido na sinalização do pH ambiente. Para tanto, a expressão dos genes hsps foi analisada em resposta ao cultivo de T. rubrum em diferentes meios de cultura, durante a exposição a antifúngicos, estresse térmico e interação com fragmentos de unha e pele humanas. O envolvimento da Hsp90 na modulação da expressão gênica, na suscetibilidade a antifúngicos e na interação de T. rubrum com fragmentos de unha humana foi avaliado utilizando-se um inibidor químico específico para esta proteína. Os resultados indicam uma expressão variável dentre os genes hsps e até mesmo dentro de cada família HSP, em resposta a cada condição ambiental ou interação a que o fungo foi exposto. Além disto, temos indício de que a expressão dos genes hsps seja modulada pelo fator de transcrição PacC, através da modulação do fator de transcrição Hsf1. Constatamos ainda, a influência de Hsp90 na susceptibilidade de T. rubrum às drogas Itraconazol e Micafungina, e no desenvolvimento de T. rubrum em fragmentos de unha humana. Esses resultados revelam a participação das proteínas HSPs em diversos aspectos do metabolismo de T. rubrum, e sugerem a participação de Hsp90 na patogenicicade e na suscetibilidade a drogas deste dermatófito
The dermatophyte Trichophyton rubrum is a filamentous, keratinophilic, and anthrophophilic fungi, being the major etiologic agent of cutaneous mycoses in humans. Its cosmopolitan distribution and the severe infection in immunocompromised patients make it one of the challenges to be faced by public health agencies worldwide. Hostpathogen interactions involve different processes related to keratin degradation and metabolic changes that allow adhesion and subsequent penetration of the infected tissue. These changes are important to the success of the infectious process and involve mechanisms that modulate gene expression, secretion of specific proteins, and metabolic adaptation, and cutaneous pH changes, essential to the establishment of the infection. Among the proteins that participate in the host-pathogen interaction are the heat shoch proteins (HSPs), related to diverse cellular processes. Thus, the hypothesis of this work was to evaluate whether T. rubrum hsp genes, as well as their major transcription factor (Hsf1), are involved in the response to adverse situations and in the interaction with the host microenvironment, and if these genes are regulated by the transcription fator PacC, a regulator of the pH signaling pathway. The expression of the hsp genes was evaluated in response to the cultivation of T. rubrum in different culture medium, during exposure to antifungal drugs, heat stress, and interaction with human nail and skin. The involvement of T. rubrum Hsp90 in the modulation of gene expression, susceptibility to antifungal drugs, and interaction with human nails was evaluated by using a chemical inhibitor, specific to this protein. Our results indicate a variable expression of the hsp genes, even among members of the same HSP family, in response to each environmental condition or interaction, to which the fungus was exposed. Furthermore, we have evidence that the hsp gene expression is modulated by the PacC transcription factor, by modulating the expression of the Hsf1 coding gene. We also found that Hsp90 is involved in T. rubrum susceptibility to the drugs Itraconazole and Micafungin, and in the development of this dermatophyte in human nails. These results reveal the involvement of HSPs in several aspects of T. rubrum metabolism, suggesting a role for Hsp90 in the pathogenicity and drug susceptibility in this dermatophyte
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9

Coumailleau, Pascal. "I - clonage et expression d'un gene de la famille hsp90 au cours du developpement chez l'amphibien urodele pleurodeles waltlIi - signification de l'interaction entre la proteine hsp90 et deux facteurs de transcription a motif helice-boucle-helice(hlh)." Paris 5, 1996. http://www.theses.fr/1996PA05S029.

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Cette these a porte sur l'etude du role de certains membres de la famille des proteines de stress de 90kda (hsc90 ou hsp90) exprimes dans les conditions physiologiques. Cette analyse a ete realisee dans un premier temps in vivo par le clonage et l'etude de l'expression d'un gene hsc90 (strictement constitutif) au cours de l'ovogenese et de l'embryogenese chez l'amphibien pleurodeles waltl. Ces resultats nous ont permis d'analyser la distribution du messager hsc90 au cours de ces deux etapes-cles du developpement. La fabrication d'un anticorps dirige specifiquement contre hsc90 nous a permis de determiner la localisation cellulaire et tissulaire de cette proteine. Le role de cette proteine a ete ensuite envisagee au cours de l'ovogenese en inhibant la fonction de la proteine par microinjection d'anticorps. Une deuxieme approche, cette fois in vitro, nous a permis d'aborder le role de la proteine hsp90 exprimee dans un systeme acellulaire lors de son interaction avec des facteurs de transcription de la famille hlh (helix-loop-helix), facteurs pour la plupart impliques dans les processus de l'embryogenese. Le premier facteur etudie est le recepteur de la dioxine (dr) appele ainsi en raison de sa forte affinite notamment pour la dioxine, une substance xenobiotique et hautement cancerigene. Les resultats permettent de delimiter clairement un domaine sur le recepteur responsable a la fois de l'affinite pour la dioxine et de la proteine hsp90. Nos resultats suggerent fortement des proprietes de chaperon pour hsp90. La proteine sim (single minded protein) est un autre facteur de transcription a motif bhlh dont les etudes recentes suggerent des fonctions importantes dans la neurogenese. Nos resultats permettent de mettre en evidence que sim est une autre proteine cible d'hsp90 et que cette derniere pourrait reguler la fonction du facteur sim.
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10

MENG, XIA. "Clonage et regulation du gene hsp90 beta de poulet mutagenese de l'hsp90 : dimerisation, localisation subcellulaire et interaction in vivo avec le recepteur des oestrogenes." Paris 6, 1995. http://www.theses.fr/1995PA066666.

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Le clonage du gene hsp90 beta confirme que la duplication de l'hsp90 alpha et beta se situe, au cours de la phylogenese, a l'epoque de l'apparition des vertebres. De plus, le messager hsp90 beta aviaire n'est pas inductible par le stress thermique contrairement aux messagers hsp90 alpha et beta de mammiferes. Les stimuli mitogenes comme le serum et l'insuline, qui induisent le messager hsp90 alpha, n'augmentent pas le taux du messager hsp90 beta. Cette regulation differencielle des hsp90 alpha et beta de poulet, pourrait etre expliquee par les divergences majeures existant au niveau du promoteur. Dans le promoteur hsp90 beta une seule boite caat et un seul element de choc thermique (hsf) sont presents 3 et 2 kb en amont de la boite tata, respectivement. La mutagenese de l'hsp90 a ete realisee pour etudier son homodimerisation, sa localisation subcellulaire, et enfin son interaction in vivo avec le recepteur nucleaire des oestrogenes (re). L'analyse des cytosols des cellules cos7 apres transfection de l'hsp90 sauvage ou mutee a demontre que la deletion de 30 acides amines en c-terminal est suffisante pour empecher la formation de dimere, que la region c-terminale de 282 acides amines est suffisante pour l'homo-dimerisation et que les deletions de plusieurs sous-regions dans cette partie empechent egalement la dimerisation de l'hsp90. L'analyse de la localisation subcellulaire des mutants exprimes dans les cellules cos7 a montre une localisation nucleaire de la region n-terminale de 285 acides amines, contenant des signaux de localisation nucleaire potentiels. Cette fonction est masquee dans les mutants moins deletes en c-terminal et dans la proteine sauvage. L'interaction in vivo entre l'hsp90 sauvage cytoplasmique et le re nucleaire est observee apres co-expression des deux proteines et re-localisation specifique d'une partie de l'hsp90 dans le noyau, a cause de son interaction avec le re. Plusieurs mutants cytoplasmiques ont ete testes pour leur capacite a migrer du cytoplasme vers le noyau via l'interaction avec le re. Nous avons montre que l'abolition de la dimerisation de l'hsp90 ne bloquait pas necessairement son interaction in vivo avec le re, ceci suggere que la dimerisation de l'hsp90 et son interaction avec le re sont deux fonctions distinctes
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11

Lele, Zsolt. "Expression, regulation and possible function of heat shock genes (Hsp47, Hsp70, Hsp90Ã and Hsp90ß) during normal development and under stress-conditions in zebrafish." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ32791.pdf.

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12

Newbury, Jane Amanda. "Characterisation of a HSP70 gene in Aspergillus nidulans." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241508.

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13

Puig, Giribets Marta. "Evolution of the hsp70 gene family at the nucleotide, genome organization and gene expression levels in Drosophila subobscura." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/663952.

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Nombrosos estudis han constatat el valor adaptatiu del ric polimorfisme d’inversions cromosòmiques al drosofíl· lid D. subobscura. No obstant això, fins ara es coneixien molt poc les bases moleculars que hi ha darrere del seu manteniment a les poblacions naturals. En cercar loci candidats, un experiment previ de xoc tèrmic va quantificar els nivells de la proteïna Hsp70 en soques homocariotípiques dels ordenaments OST, O3+4+8 i O3+4. Inesperadament, els individus de l’ordenament càlid O3+4 mostraven nivells incrementats d’aquesta proteïna, en absència d’estrès tèrmic, que no augmentaven després del xoc tèrmic. Malauradament, en el moment en què es va dur a terme l’experiment hi havia moltes incògnites sobre l’organització molecular del locus Hsp70IR a D. subobscura. Els resultats prèviament esmentats, van donar peu al present treball de tesi, els objectius del qual són localitzar el locus Hsp70IR al cariotip i conèixer-ne l’organització genòmica, característiques moleculars i expressió gènica en diversos ordenaments cromosòmics d’interès que inclouen la regió genòmica on es troba la família gènica hsp70: O3+4+16+2, O3+4+8, O3+4 i OST. Gràcies a la seqüència d’un clon de la genoteca d’una línia OST i a còntigs del genoma de D. subobscura, hem pogut dissenyar una sonda a partir de la regió codificant de hsp70 que ens ha permès determinar la localització del locus on es troba aquesta família gènica (Hsp70IR) mitjançant hibridació in situ (ISH). Paral· lelament, hem pogut completar la seqüenciació d’una regió de 9-10 kb al locus Hsp70IR en 12 línies isogèniques per als ordenaments esmentats i a les espècies properes D. madeirensis i D. guanche per aclarir l’evolució d’aquest locus en els darrers 1,8 - 2,8 milions d’anys (Ma). Els resultats de la ISH van mostrar un únic punt d’hibridació a la banda 94A del segment distal (SI) del cromosoma O que coincidia els 4 cariotips estudiats: O3+4+16+2, O3+4+8, O3+4 i OST. Les seqüències corresponents a les 12 línies isogèniques i a D. madeirensis i D. guanche indiquen que en aquestes tres espècies del clúster subobscura, el locus Hsp70IR consta de dues còpies paràloges de 2,5 – 3,0 kb en orientació divergent i separades per una regió espaiadora central no duplicada de 0,5 – 1,4 kb. Les dues còpies mostren un elevat grau de conservació entre els diferents ordenaments i espècies analitzats, mentre que la regió espaiadora central és altament polimòrfica. Entre els aspectes més rellevants de l’anàlisi del polimorfisme, destaquem l’elevada conservació de les regions codificadores (CDSs) i els diferents elements reguladors en cis (CREs) al promotor proximal de tots els gens hsp70 analitzats, que indicarien que aquests són funcionals a totes les línies estudiades, i que la seva regulació podria ser similar. Curiosament, a nivell de seqüència, les regions paràlogues del promotor proximal i el CDS tendeixen a ser significativament més similars dins del mateix ordenament i, en alguns casos, dins la mateixa línia, probablement com a resultat de conversió gènica ectòpica. Per últim, hem dut a terme la quantificació dels nivells basals de mRNA i proteïna en mascles i femelles adults de sis línies isogèniques per a l’ordenament fred OST i sis per a l’ordenament càlid O3+4. La quantificació dels nivells de mRNA indica que els nivells són similars entre els dos ordenaments però en canvi aquests difereixen entre mascles i femelles de l’ordenament càlid O3+4. Així mateix, la quantificació dels nivells de la proteïna Hsp70 suggereix que no hi ha diferències entre sexes ni entre els dos ordenaments, però en canvi observem una interacció significativa entre sexe i ordenament. Aquests resultats, tant per a mRNA com per a proteïna, indiquen que l’expressió de hsp70 podria estar influïda pel sexe.
Numerous studies have confirmed the adaptive value of the rich chromosomal inversion polymorphism in the drosophilid D. subobscura. However, until recently very little was known about the molecular basis behind its maintenance in natural populations. In search of candidate loci, a previous heat shock experiment quantified Hsp70 protein levels in homokaryotypic strains for the OST, O3+4+8 and O3+4 arrangements. Unexpectedly, individuals of the warm climate-associated O3+4 arrangement showed increased levels in absence of thermal stress that did not boost after the heat shock. Unfortunately, by the time this experiment was performed there was very little data available on the molecular organization of the Hsp70IR locus in D. subobscura. The previously mentioned results led to the present thesis work, whose objectives are to locate the Hsp70IR locus in the karyotype and to know the genomic organization, molecular characteristics and gene expression patterns in several representative chromosomal arrangements that comprise the genomic region where the hsp70 gene family is located: O3+4+16+2, O3+4+8, O3+4 and OST. Using the sequence of a clone from an OST line genomic library and contigs from the unassembled genome of D. subobscura, we designed a probe from the hsp70 coding region that enabled us to determine the location of the locus by in situ (ISH) hybridization. Concomitantly, we completed the sequencing of a 9-10 kb region in the Hsp70IR locus in 12 lines isogenic for the aforementioned arrangements and in D. madeirensis and D. guanche to shed light on the evolution of this locus in the last 1.8 - 2.8 million years (myr). ISH results showed a single hybridization site in the 94A band in the distal segment (SI) of the O chromosome coincident in the 4 studied karyotypes: O3+4+16+2, O3+4+8, O3+4 and OST. The sequences corresponding to the 12 isogenic lines and to D. madeirensis and D. guanche indicated that in these three species of the subobscura cluster, the Hsp70IR locus consists of two 2.5 - 3.0 kb long paralogous copies in divergent orientation separated by a 0.5 - 1.4 kb nonduplicated central spacer region. The two copies show a high degree of conservation between the different gene arrangements and species analyzed, while the central spacer region is highly polymorphic. Among the most relevant aspects of polymorphism analyses, we highlight the high degree of conservation in the coding regions (CDSs) and the cis-regulatory elements (CREs) in the proximal promoter of all the analyzed hsp70 genes, which might indicate that these are functional in all studied lines, and that their regulation might be similar. Curiously, at the sequence level, the paralogous 5'-UTR and CDS regions tend to be significantly more similar within the same arrangement and, in some cases, within the same line, probably as a result of ectopic gene conversion. Lastly, we carried out the quantification of basal hsp70 mRNA and protein levels in adult males and females of six lines isogenic for the cold climate-associated OST and six for the warm climate-associated O3+4 arrangements. Basal mRNA quantification results indicate that the two arrangements exhibit similar levels, yet significant differences are observed between males and females of the warm O3+4 arrangement. Regarding the quantification of basal Hsp70 protein levels, these suggest that there are no differences between sexes nor between the two arrangements, but instead we observe a significant interaction between sex and arrangement. Overall, the results for both, mRNA and protein data, indicate that hsp70 expression might be influenced by sex.
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14

Girvitz, Tara L. "HSP80 of Neurospora crassa, gene sequence and developmental expression." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq20828.pdf.

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15

Christen, Susan Ehlert. "Amplificação do gene da Chaperonina HSP10 do Trypanosoma evansi." Universidade do Estado de Santa Catarina, 2010. http://tede.udesc.br/handle/handle/846.

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The trypanosomiasis is enzootic caused by several species of the genus Trypanosoma. It is a hemoflagellate widely distributed and of great veterinary importance, because infects a wide variety of mammals. Trypanosoma evansi is the causative agent of disease popularly known as surra , which has great economic importance in Africa, Asia and South America. These protozoa possess digenetic life cycles. When the parasites move from vector to host they suffer a heat shock. The HSPs are found in several pathogens, where the heat shock is a natural event of their biology. The heat shock response is a homeostatic mechanism that protects cells from the deleterious effects of environmental stress. The HSPs have a key role in intracellular work such as DNA replication, cell division, transcription, translation, functions in membrane transport proteins as well as providing assistance to correct protein folding nascent and unfolded by stress accumulation. This work aimed to amplify the HSP10 gene, to be able, afterwards, to observe its expression in trypanosomatids. Rats Wistar were infected with T. evansi, the parasites were purified, the DNA and RNA extraction was made, beyond the reverse transcriptase, PCR, transformation into E. coli DH5α and sequencing of clones. The bands that corresponded to the size of HSP10 gene were selected for clone. The constructions of the inserts selected were subjected to sequencing to verify the correct construction of the clones. The sequencing analysis showed that the sequence obtained has a homology of 40% corresponding to HSP10 hypothetical T. brucei. This is one of the first papers that attempted to identify a gene family of HSPs in T. evansi, that should be used as a chemotherapeutic target
A tripanossomíase é uma enzootia ocasionada por diversas espécies do gênero Trypanosoma. Este é um hemoflagelado amplamente distribuído e de grande importância veterinária, pois infecta uma grande variedade de mamíferos. O Trypanosoma evansi é o agente causador da doença denominada popularmente como surra, que possui grande importância econômica na África, Ásia e América do Sul. Estes protozoários possuem ciclos de vida digenéticos. Quando os parasitos passam do vetor para o hospedeiro estes acabam sofrendo um choque térmico. As HSPs são encontradas em uma variedade de patógenos, onde o choque térmico é um evento natural de sua biologia. A resposta de choque térmico é um mecanismo homeostático que protege as células dos efeitos deletérios do estresse ambiental. As HSPs possuem um papel fundamental no trabalho intracelular como replicação de DNA, divisão celular, transcrição, tradução, funções nas membranas, transporte de proteínas, além de darem assistência correta ao enovelamento de proteínas nascentes e desenoveladas pelo acúmulo de estresse. Este trabalho teve como intuito amplificar o gene da HSP10, para que seja possível futuramente observar sua expressão nos tripanosomatídeos. Ratos Wistar foram infectados com T. evansi, os parasitos foram purificados, efetuou-se a extração de DNA e RNA, além da transcrição reversa, PCR, transformação em E. coli DH5α e o seqüenciamento dos clones. As bandas que corresponderam ao tamanho do gene HSP10 foram selecionadas para clonagem. As construções dos insertos selecionados foram submetidos ao sequenciamento a fim de verificar a construção correta dos clones. A análise do seqüenciamento demonstrou que a sequência obtida possui uma homologia de 40% correspondente a HSP10 hipotética de T. brucei. Este é um dos primeiros trabalhos que buscam identificar um gene da família das HSPs em T. evansi, que poderá ser usado como alvo quimioterápico
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16

Trotman, Jackson B. "New Insights into the Biochemistry and Cell Biology of RNA Recapping." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1523896565730483.

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17

Krenek, Sascha, Martin Schlegel, and Thomas U. Berendonk. "Convergent evolution of heat-inducibility during subfunctionalization of the Hsp70 gene family." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-126934.

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Background: Heat-shock proteins of the 70 kDa family (Hsp70s) are essential chaperones required for key cellular functions. In eukaryotes, four subfamilies can be distinguished according to their function and localisation in different cellular compartments: cytosol, endoplasmic reticulum, mitochondria and chloroplasts. Generally, multiple cytosol-type Hsp70s can be found in metazoans that show either constitutive expression and/or stress-inducibility, arguing for the evolution of different tasks and functions. Information about the hsp70 copy number and diversity in microbial eukaryotes is, however, scarce, and detailed knowledge about the differential gene expression in most protists is lacking. Therefore, we have characterised the Hsp70 gene family of Paramecium caudatum to gain insight into the evolution and differential heat stress response of the distinct family members in protists and to investigate the diversification of eukaryotic hsp70s focusing on the evolution of heat-inducibility. Results: Eleven putative hsp70 genes could be detected in P. caudatum comprising homologs of three major Hsp70-subfamilies. Phylogenetic analyses revealed five evolutionarily distinct Hsp70-groups, each with a closer relationship to orthologous sequences of Paramecium tetraurelia than to another P. caudatum Hsp70-group. These highly diverse, paralogous groups resulted from duplications preceding Paramecium speciation, underwent divergent evolution and were subject to purifying selection. Heat-shock treatments were performed to test for differential expression patterns among the five Hsp70-groups as well as for a functional conservation within Paramecium. These treatments induced exceptionally high mRNA up-regulations in one cytosolic group with a low basal expression, indicative for the major heat inducible hsp70s. All other groups showed comparatively high basal expression levels and moderate heat-inducibility, signifying constitutively expressed genes. Comparative EST analyses for P. tetraurelia hsp70s unveiled a corresponding expression pattern, which supports a functionally conserved evolution of the Hsp70 gene family in Paramecium. Conclusions: Our analyses suggest an independent evolution of the heat-inducible cytosol-type hsp70s in Paramecium and in its close relative Tetrahymena, as well as within higher eukaryotes. This result indicates convergent evolution during hsp70 subfunctionalization and implies that heat-inducibility evolved several times during the course of eukaryotic evolution.
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18

Martello, Fernanda Gonçalves. "Hsp60 e imunorregulação: estratégias para identificação de peptídeos imunorreguladores." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/5/5146/tde-15042010-110232/.

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As proteínas de choque térmico (Hsp) apresentam importantes funções homeostáticas e podem induzir respostas imunológicas tanto inflamatórias como reguladoras. Por essas propriedades, as Hsp e seus peptídeos têm grande potencial como agentes imunomoduladores. Neste estudo, o nosso objetivo foi identificar peptídeos da Hsp60 com potencial imunorregulador, a partir da análise de sua capacidade de modificar, in vitro a expressão de genes imunorreguladores (REGULA) ou inflamatórios (INFLAMA) em células mononucleares do sangue de indivíduos sadios. A análise desse painel REGULA/INFLAMA nos mostrou que os principais peptídeos potencialmente imunorreguladores estão presentes na região N-terminal da Hsp60. Selecionamos os 3 peptídeos que mostraram as maiores razões REGULA/INFLAMA (N2, N6 e N7) para serem testados nos demais experimentos. A análise das citocinas induzidas pelos peptídeos nos mostrou que existe correspondência entre a presença do RNA mensageiro e a proteína produzida e, o peptídeo N7 induziu uma alta razão IL-10/IFN-. Os peptídeos selecionados interagiram diretamente com linfócitos T purificados, o que mostra que a atividade dos peptídeos da Hsp60 independe de APC. Apesar de diferenças entre o efeito na população celular heterogênea de PBMC e na mais homogênea de linfócitos T, os peptídeos da Hsp60 induziram um predomínio de modificações REGULA com indução sustentada de Foxp3 e GATA-3. Os peptídeos selecionados, N2, N6 e N7, foram capazes de inibir a resposta proliferativa alogeneica (maior inibição: peptídeo N7 60,53%) e induzida pelo anticorpo anti-CD3 (maior inibição: peptídeo N2 31,01%). A partir desses resultados, concluímos que o nosso painel de expressão gênica REGULA/INFLAMA foi adequado para identificar peptídeos da Hsp60 predominantemente reguladores. Dentre os possíveis mecanismos supressores desses peptídeos, apontamos a ação das citocinas reguladoras IL-10, TGF-, a inibição de fatores de transcrição próinflamatórios como T-bet e RORt, e a geração de células T reguladoras. O próximo passo, já em andamento no nosso laboratório, será testar esses peptídeos em modelos de transplante e doenças autoimunes visando, no futuro, o seu uso em aplicações terapêuticas na clínica.
Heat shock proteins (HSPs) have dual immunologic functional activity inducing both proinflammatory and regulatory responses. These properties place HSPs and their peptides as molecules displaying great potential as immunomodulatory agents. In this study, our goal was to identify potential immunoregulatory Hsp60 peptides, analyzing their capacity to modify the expression of immunoregulatory (REG) or proinflammatory (INFLAMMA) genes in PBMC of healthy individuals. The REG/INFLAMMA gene panel analysis showed that most peptides displaying an immunoregulatory profile belong to the Hsp60 N-terminal region. We selected 3 peptides that showed the highest REG/INFLAMMA ratio (N2, N6 and N7) for functional studies. Cytokine analysis showed good correspondence between messenger RNA and protein production induced by the peptides, and N7 peptide induced high IL-10/IFN- ratio. The selected peptides also interacted directly with purified T lymphocytes, indicating an APC-independent activity for Hsp60 peptides. Despite differences between the effect on PBMC and on purified lymphocytes, Hsp60 peptides induced predominantly REG type of gene expression modifications, with the induction of Foxp3 and GATA-3. The selected peptides, N2, N6 and N7, were capable of inhibiting allogeneic proliferation (highest inhibition: N7 peptide 60,53%) and the proliferation induced by anti-CD3 antibody (highest inhibition: N7 peptide 31,01%). We concluded that our REG/INFLAMMA gene expression panel was appropriate to indentify regulatory Hsp60 peptides. Among their possible suppressive mechanisms, we can point out the action of the regulatory cytokines IL-10 and TGF-, the inhibition of proinflammatory transcription factors T-bet and RORt and the generation of regulatory T cells. The next step, ongoing in our lab, is to test these peptides in experimental models of allotransplantation and autoimmune diseases, aiming at future therapeutic applications in the clinic.
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Lopes, Valéria Stefania. "Caracterização da família de genes HSP20 em Glycine max." Universidade Estadual de Londrina, EMBRAPA. Centro de Ciências Exatas. Programa de Pós-Graduação em Biotecnologia, 2012. http://www.bibliotecadigital.uel.br/document/?code=vtls000175506.

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As pequenas proteínas de choque térmico (HSP20) são frequentemente associadas com a resposta das plantas ao estresse causado por fatores abióticos e, mais recentemente, têm sido também associadas a resposta aos estresses bióticos. Nas plantas, os genes Hsp20 representam a classe mais abundante dentre as proteínas de choque térmico, mas ainda pouco se conhece sobre essa família de genes em soja. Devido à suas aparentes multifuncionalidades, essas proteínas são alvos promissores para o desenvolvimento de variedades agrícolas melhor adaptadas a condições de estresses abióticos e bióticos, até mesmo quando combinados. Dessa forma, o presente trabalho realizou a caracterização molecular in silico das regiões codificadoras e reguladoras da família de genes codificadores para HSP20 de soja, com foco em sua distribuição no genoma, localização subcelular, divisão em subfamílias, estrutura secundária e regulação frente a estresses bióticos e abióticos, além da identificação de padrões de cis elementos, potencialmente envolvidos na resposta da soja a nematóides. Após a prospecção de genes anotados em bancos de dados do genoma da soja como Hsp20, foram obtidos 76 modelos gênicos. Dentre estes, apenas 52 modelos gênicos fizeram parte dos potenciais candidatos a GmHsp20 (Glycine max-Hsp20), devido as suas características estruturais, de cis elementos e de expressão. Em seguida, foram identificados, a partir das análises in vivo, 45 genes como Hsp20 de soja, distribuídos em 11 subfamílias. Para cada uma dessas, foi possível observar padrões de estrutura secundária específicos. Dentre os 45 genes GmHsp20 responsivos ao estresse de calor, 5 foram também responsivos ao estresse de frio e outros 5 ao estresse por infecção pelo nematóide M. javanica. Além disso, foram observados mais dois genes responsivos ao estresse biótico, mas não ao choque térmico. Obtiveram-se modelos operacionais de promotores para os genes responsivos a cada tipo de estresse analisado. Entre os cis elementos identificados nos Hsp20, que respondem a infecção por M. javanica, estão os Wbox, CAAT box, ABRE e MYB, além do elemento HSE/Heat. Os promotores responsivos ao estresse biótico seguiram padrões de composição e distribuição de cis elementos, descritos na literatura como relacionados a esse tipo de estresse e outros. Tais resultados irão auxiliar na geração de tecnologias de expressão dirigida, ainda mais avançadas, e novos genótipos de soja cada vez mais adaptados a condições combinadas de estresse.
The small heat shock proteins (HSP20) are often associated in plant stress response caused by abiotic factors and, more recently, have also been associated with response to biotic stresses. The Hsp20 genes represent, in plants, the most abundant class among the heat shock proteins, but little is known about this gene family in soybean. Due their apparent multifunctionality, these proteins are promising targets to the crop varieties development for better conditions adapted to biotic and abiotic stresses, even when they are combined. Thus, the present study conducted an in silico molecular characterization of regulatory and coding regions of HSP20 genes from soybean, focus in its genome distribution, subcellular localization, division into subfamilies, secondary structure and regulation under biotic and abiotic stresses, besides the identification patterns to cis elements potentially involved in the response to nematodes. After the exploration of Hsp20 genes annotation in soybean genome databases, 76 gene models were obtained. After in silico analysis, just 52 gene models were part of the GmHsp20 potencial candidates due to their structural characteristics of cis elements and expression profile. In addition, based on in vivo analysis, 45 soybean Hsp20 genes were identified, distributed in 11 subfamilies, for which is possible to observe a specific secondary structure for each one. Among the 45 GmHsp20 genes heat stress responsives, 5 genes were cold stress responsive and other five were nematode infection by M. javanica responsive. Moreover, two genes were observed being responsive to biotic stress, but they weren't responsive to thermal shock. Operational Models of Hsp20 promoters were obtained to responsive genes to each stress condition examined in this study. Among the identified cis elements in Hsp20 soybean genes that were responsive to M. javanica infection were W box, CAAT box, ABRE and MYB, besides the HSE / Heat element. Promoters responsive to biotic stress in soybean follows composition and distribution standards of cis elements, as described in the literature to be related to this type of stress. These results, such as responsive genes and promoters to many different stresses, can assist in generation of expression directed technologies even more advanced and new soybean genotypes more adapted to under combined stress conditions.
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20

Rabinowitz, Joseph Elias 1962. "The proteolytic activity of hsp70 from human and Drosophila melanogaster." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276920.

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A proteolytic activity has been shown to be associated with the heat shock protein 70 (hsp70). In order to study this, I have constructed RNA transcribing vectors with the coding sequences of the D. melanogaster (pBUG7) and the human (pMAN70) genes coding hsp70, and with an internal deletion (pBUG301) in D. melanogaster. Proteins from 37 kDa to 70 kDa were translated in a rabbit reticulocyte lysate in the presence of 35S-methionine from RNA synthesized in vitro off the full length templates (pBUG7, and pMAN70), or altered templates. Restriction digestion of pBUG7 with BamH I and Nar I yields templates that produce carboxy-terminal truncated proteins of 37 kDa and 61 kDa respectively. The full length and the truncated proteins contain a proteolytic activity when assayed by SDS/PAGE in two dimensions. The internally deleted protein does not maintain the proteolytic activity. The proteolytic activity was shown not to be the result of non-enzymatic cleavage. A general serine proteinase inhibitor eliminates the proteolytic activity of the full length human and D. melanogaster hsp70. This evidence shows that the proteolytic activity is directly connected to hsp70.
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21

Silva, Mariana Sá e. "COMPARAÇÃO ENTRE TESTES BIOQUÍMICOS E ANÁLISE DA SEQUÊNCIA PARCIAL DO GENE hsp60 PARA A IDENTIFICAÇÃO DE ISOLADOS DE Streptococcus equi." Universidade Federal de Santa Maria, 2005. http://repositorio.ufsm.br/handle/1/10217.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Streptococcus equi is the etiological agent of strangles. Opportunistic agents from the same group are frequently isolated from horses with strangles and may induce mistake diagnostic. Among the subspecies of S. equi the phenotypic characteristics are almost undistinguishable; however the pathogenic potential is widely differentiated. The objective of this study was to determine the phenotypic and molecular characteristics of S. equi isolates obtained from samples of clinical cases of strangles by sequencing the hsp60 gene. By phenotypical assays 26 strains of Streptococcus sp. were identified, 18 were characterized as S. equi subsp. equi, five as S. equi subsp. zooepidemicus, two as S. dysgalactiae subsp., equisimilis, and one as Streptococcus sp.; However using molecular characterization, 21 isolates were identified as S. equi subsp. equi and five as S. equi subsp. zooepidemicus. The analysis of the hsp60 sequence is a good discriminatory tool and can be useful as a method of differentiation, principally for the characterization of atypical isolates
Streptococcus equi subesp. equi é o agente etiológico da adenite eqüina. Outros agentes pertencentes ao mesmo grupo, como S. equi subesp. zooepidemicus são freqüentemente isolados de animais com sinais de adenite, podendo originar diagnósticos equivocados. As diferenças bioquímicas são pequenas para as subespécies de S. equi, enquanto o potencial virulento é muito diferenciado, havendo, portanto, necessidade de uma correta diferenciação entre os isolados. O presente trabalho teve como objetivo realizar a comparação fenotípica e molecular de isolados de S. equi, obtidos de casos de adenite eqüina, pela análise de seqüências parciais do gene hsp60. De 26 amostras de Streptococcus sp. analisadas, 18 foram bioquimicamente identificadas como S. equi subesp. equi, cinco como S. equi subesp. zooepidemicus, dois isolados S. dysgalactiae subesp. equisimilis e para um isolado não foi possível determinar a espécie. Pela análise das seqüências, 21 isolados foram identificados como S. equi subesp. equi e cinco como S. equi subesp. zooepidemicus. Dentre os isolados utilizados, quatro apresentaram divergência entre os métodos utilizados. A análise de seqüências do gene hsp60 possui um bom poder discriminatório e pode ser um importante método auxiliar na diferenciação de isolados de Streptococcus equi, especialmente para isolados com padrão atípico de fermentação de açucares
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22

Codonho, Bárbara Santoni 1988. "Avaliação do efeito da superexpressão da proteína HSP70 em Leishmania (Leishmania) amazonensis." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317275.

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Orientadores: Selma Giorgio, Fernanda Ramos Gadelha
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: As leishmanioses são um conjunto de doenças causadas pelo protozoário do genêro Leishmania, que atingem milhões de pessoas por ano. O tratamento é realizado primeiramente com antimoniais pentavalentes e, em casos de resistência, são indicadas a pentamidina ou anfotericina B. Todos estes fármacos são tóxicos e induzem efeitos colaterais nos pacientes. Devido a dificuldades no tratamento, o estudo de moléculas presentes no parasita se torna importante. Dentre essas, as heat shock proteins 70 (HSP70) são proteínas essenciais para o ciclo de vida da Leishmania. Durante a passagem do vetor para o hospedeiro vertebrado, o parasita encontra vários tipos de estresses que induzem a uma maior expressão da HSP70. Nesse projeto avaliou-se os efeitos da superexpressão da HSP70 em Leishmania (Leishmania) amazonensis, comparando-se parasitas que superexpressam a proteína HSP70 (pTEX-HSP70) com parasitas contendo somente o vetor (pTEX). Os resultados mostraram que os promastigotas transfectados pTEX e pTEX-HSP70 apresentaram vários aspectos ultraestruturais semelhantes aos não transfectados (WT), porém mostraram ser maiores e com o tamanho da área nuclear maior. A superexpressão da proteína HSP70 conferiu aos parasitas uma fase estacionária de proliferação mais estendida do que a observada em parasitas pTEX. Uma maior resistência e capacidade proliferativa foram observadas nos parasitas pTEX-HSP70 quando submetidos a diferentes condições de estresses (tratamentos com H2O2, choque térmico e ambiente hiperbárico), em relação a parasitas pTEX. Os resultados também mostraram que parasitas pTEX e pTEX-HSP70 infectam culturas de macrófagos peritoneais e macrófagos humanos derivados de sangue periférico, em taxas (% de infecção e número de amastigotas/macrófago) semelhantes a de parasitas WT. O processo de infecção em camundongos BALB/c mostrou que o tamanho da lesão induzida pelos parasitas pTEX e pTEX-HSP70 na pata foi diferente nas primeiras semanas, mas semelhante no curso final da infecção. Adicionalmente, as cargas parasitárias nas lesões dos camundongos BALB/c infectados com os parasitas pTEX e pTEX-HSP70 foram semelhantes, mas maiores que as cargas parasitárias nas lesões induzidas por WT. Além disso, os baços dos camundongos infectados com os parasitas pTEX e pTEX-HSP70 apresentaram visceralização. Ensaios da bioenergética destes promastigotas mostraram que parasitas pTEX-HSP70 apresentam maiores taxas de consumo de O2 do que parasitas pTEX, apesar de apresentarem produção de ATP semelhante. A produção de superóxido nos parasitas pTEX-HSP70 e pTEX foram similares, apesar da liberação de H2O2 ser bem inferior nos de parasitas pTEX-HSP70. Os resultados obtidos indicam que a superexpressão da proteína HSP70 protege a L.(L.) amazonensis de situações de estresse imediato, mas não interfere com a sua capacidade infectiva
Abstract: Leishmaniasis are a group of diseases caused by the protozoan genus Leishmania, which affect millions of people each year. The treatment is performed primarily with pentavalent antimony and resistance cases are indicated pentamidine or amphotericin B. All these drugs are toxic and induce side effects in patients. Due to difficulties in treatment, the study of molecules present in the parasite becomes important. Among these, the heat shock protein 70 (HSP70) proteins are essential for the life cycle of Leishmania. During the transition from vector to vertebrate host, the parasite finds various types of stresses that induce a higher expression of HSP70. In this project was evaluated the effects of overexpression of HSP70 in Leishmania (Leishmania) amazonensis, comparing parasites that overexpressing HSP70 (pTEX-HSP70) protein with parasites containing the empty vector (pTEX). The results showed that transfected promastigotes pTEX and pTEX-HSP70 showed several similar ultrastructural aspects similar to promastigotes of L.(L.) amazonensis untransfected (WT), but proved to be larger and the size of the largest nuclear area. Overexpression of HSP70 protein gave the parasites a stationary phase of proliferation more extended than that observed in parasites pTEX. Higher strength and better proliferative capacity were observed in parasites pTEX-HSP70 when submitted to different stress conditions (hydrogen peroxide, heat shock treatments and hyperbaric environment), in relation to parasites pTEX. The results also showed that pTEX and pTEX-HSP70 parasites infect cultures of peritoneal macrophages and human peripheral blood-derived macrophages in rate (% infection and the number of amastigotes / macrophage) similar to WT parasites. The process of infection in BALB/c mice showed that the size of the induced parasitic pTEX and pTEX-HSP70 foot injury was different in the first few weeks but similar in the final course of infection. Additionally, parasitic loads on the lesions of BALB/c mice infected with pTEX and pTEX-HSP70 parasites were similar, but larger than the parasitic loads in lesions induced by WT. Moreover, spleens from infected with pTEX and pTEX-HSP70 parasites mice showed visceralization. Assays of bioenergetics promastigotes showed that these pTEX-HSP70 parasites consume more O2 than pTEX parasites, despite showing similar ATP production. Superoxide production in parasites pTEX and pTEX-HSP70 were similar, despite the release of hydrogen peroxide is considerably lower than pTEX-HSP70 parasites. The results indicate that overexpression of HSP70 protein protect L.(L.) amazonensis in immediate situations of stress, but does not interfere with its infective capacity
Mestrado
Imunologia
Mestra em Genética e Biologia Molecular
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23

Milner, Caroline M. "Characterisation of novel genes in the human major histocompatibility complex : the HSP70 & G9a genes." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302867.

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24

Sung, Dong Yul. "Characterization of Arabidopsis heat shock protein 70 (hsp70) gene family and microarray analysis of gene expression in response to temperature extremes." [Gainesville, Fla.] : University of Florida, 2001. http://purl.fcla.edu/fcla/etd/UFE0000356.

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Thesis (Ph. D.)--University of Florida, 2001.
Title from title page of source document. Document formatted into pages; contains xii, 140 p.; also contains graphics. Includes vita. Includes bibliographical references.
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25

Vasquez-Robinet, Cecilia. "Relationships Between Expression of Heat Shock Protein Genes and Photosynthetic Behavior During Drought Stress in Plants." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27009.

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Heat shock proteins (HSPs) are expressed in response to environmental stresses. Compared to other kingdoms, plant HSP families are larger, presumably the result of adaptation to a wide range of stresses. Following on an analysis of drought stress characteristics in loblolly pine (Watkinson et al., 2003), expression patterns of HSP gene expression during photosynthetic acclimation were examined. One cycle of mild (-1Mpa) followed by two cycles of severe stress (-1.7Mpa) were probed for conditioning effects. Photosynthetic acclimation occurred after the first cycle. No acclimation occurred without the first mild cycle. Microarray/RT-PCR analyses showed that a pine homolog to GRP94 (ER-resident HSP90) was up-regulated after rehydration coincident with acclimation. This GRP94 is closely related to GRP94 from the desiccation tolerant plant X. viscosa, supporting the importance of this gene during acclimation to water deficit. HSP genes whose products localized to the mitochondrion showed gradual up-regulation after consecutive cycles of severe drought. The Arabidopsis pine GRP94 homolog, (AtHSP90-7) was then analyzed, using bioinformatics (Pati et al., 2006) and laboratory tools. Genes encoding putative candidate co-chaperones for GRP94 and other HSP90s were discovered, which contained water stress-related cis-elements. Arabidopsis (Col-0) wild type and two T-DNA insertion mutants in HSP90-7 were used to study the importance of this gene for photosynthetic acclimation. Only the mutants were able to acclimate to drought stress, with the level of AtHSP90-7 expression in the mutants being reduced compared to the wild type. AtHSP90-7 may have a different role in Arabidopsis, and its reduced expression activated other protective genes (Klein et al., 2006). Responses to extreme drought in resistant (Sullu) and susceptible (Negra Ojosa) lines of Andean potatoes were also compared in order to identify relationships between HSPs gene expression, and tolerance, defined as the ability to maintain photosynthesis at 50% after 25 days of drought and to recover from the stress. Tolerance was correlated with up-regulation of HSPs (mostly chaperonins) and antioxidant genes all of whose gene products are located in the chloroplast.
Ph. D.
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26

Gross, Tiffany Lauren. "Aedes aegypti Heat Shock 70 Genes and their Inducible Promoters." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/28305.

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Aedes aegypti is an important vector of the viruses that cause dengue fever, dengue hemorrhagic fever, and yellow fever. In depth genetic studies of vector species have been made possible due to the availability of genome sequences and techniques for producing stably transformed mosquitoes. These resources have also contributed to the establishment of new genetics-based approaches to the control of vector borne disease. Genetic studies of Ae. aegypti have benefited from the ability to drive targeted transgene expression, however a ubiquitous inducible promoter has not been identified in this mosquito. The Drosophila melanogaster heat shock 70 promoter has been shown to drive inducible expression in heterologous systems; however, DmHsp70 possesses significant basal activity in Aedes aegypti. This study characterized the sequence and expression of the heat shock 70 genes of Aedes aegypti. AaHsp70 genes were found to be organized in two clusters, each comprised of three divergent pairs. AaHsp70 genes exhibited robust expression upon heat shock in larvae, pupae, and adults as well as in heads, salivary glands, midguts and ovaries. Genomic regions upstream of AaHsp70 genes were found to drive heat-inducible expression of a reporter in both cell and embryo assays. Deletion analysis of AaHsp70-derived promoters yielded two ~1.5 kb genomic fragments that maintained robust heat inducibility in these systems. Aedes aegypti were transformed with AaHsp70-luciferase gene cassettes using the transposable element Mos1. AaHsp70-luciferase transcripts accumulated specifically after heat shock, and displayed a pattern of rapid induction and decay similar to endogenous AaHsp70 genes. Heat-induced expression of luciferase was observed in transgenic larvae, pupae and adults as well as heads, midguts and ovaries but not salivary glands, with levels varying between transgenic strains. The effect of heat shock on the endogenous RNAi pathway as well as the effect of blood feeding on the expression of AaHsp70 genes was investigated, though reproducible results could not be obtained using the assays employed. In conclusion, the heat shock 70 gene family of Aedes aegypti was identified and characterized. The AaHsp70 promoters described could be valuable for gene function studies as well as for the precise timing of the expression of anti-pathogen molecules.
Ph. D.
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27

Bienemann, Alison Sarah. "Assessing viral vectors as gene therapy agents and the study of neuroprotective effects of HSP70." Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492644.

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The experiments outlined in this thesis were designed to: (i) evaluate the utility of Equine infectious anaemia lentiviral (EIAV) vectors as gene therapy agents in the CNS; (ii) investigate the function and neuroprotective role of Hsp70 and Hsp40.
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28

Lyons, Jarrod. "Identification and partial characterisation of the HSP70 gene of the South African abalone Haliotis midae." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/10952.

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Identifying genes which are up-regulated in response to stress has become important in understanding invertebrate immunity. The HSP70 gene from Haliotis midae was successfuly cloned and sequenced, and was found to have highest similarity (99%) with Haliotis diversicolor.
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29

Rodrigues, Thuana Marcolino Mota. "Análise do perfil de expressão de genes da família Hsp70 de Trichoderma asperellum (TR356) durante o micoparasitismo e estresses abióticos." Universidade Federal de Goiás, 2018. http://repositorio.bc.ufg.br/tede/handle/tede/8258.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The genus Trichoderma ssp, is today the group of species most commonly studied and used to act in agriculture as biological control against phytopathogens. Its rapid mycelial growth, associated with high production of conidia, synthesis of several antibiotics and ability to live in different forms (saprotrophic, symbiont or mycoparasite) are characteristics that make it attractive for this purpose. The relation of mycoparasitism, as well as oscillations in environmental conditions, naturally causes cell stress and consequent response to the stressing agent. This response occurs through changes in cellular metabolism, activating its defense mechanisms that include the performance of heat shock proteins (Hsp). The objective of this work was to identify the Hsp70 family of Trichoderma asperellum and to analyze the expression of three genes encoding proteins of this family during mycoparasitism and in situations of thermal and ethanol stress. The identification of the T. asperellum Hsp70 proteins was possible from the database analysis (JGI) of the T. asperellum genome, available, but not annotated. We identified a total of 12 proteins from the Hsp70 family in T. asperellum, three of which were selected for gene expression assays. Paired cultivation was carried out between T. asperellum and phytopathogens: Sclerotinia sclerotiorum and Fusarium oxysporum in three phases of mycoparasitism: pre-contact, contact and post-contact. We verified that the expression of Tahsp70a, Tahsp70b and Tahsp70c genes varies according to the phases of the mycoparasitism and the phytopathogen studied. Expression of hsp70 under thermal stress was evaluated at the 38 °C condition for 30 minutes, 1, 2 and 4 hours and at the conditions of 4, 10 and 32 °C for 1 hour. Ethanol stress was also performed for 1 hour. During the thermal stress Tahsp70a and Tahsp70b presented higher induction and the Tahsp70c gene had its highest induction in the cold shock at 4 °C. In ethanol stress the analyzed genes did not present significant expression.
O gênero Trichoderma ssp, constitui hoje o grupo de espécies de fungos mais estudadas e comumente usadas para atuar na agricultura como controle biológico contra fitopatógenos. Seu rápido crescimento micelial, associado a alta produção de conídios, síntese de diversos antibióticos e capacidade de viver de diversas formas (saprotrófica, simbionte ou micoparasita) são características que o tornam atraente para esse fim. A relação de micoparasitismo, bem como as oscilações nas condições ambientais, geram naturalmente estresse sobre as células desse fungo e consequente resposta ante o agente estressante. Esta resposta ocorre através de mudanças no metabolismo celular, ativando seus mecanismos de defesa que incluem o desempenho de proteínas de choque térmico (Hsp). O objetivo deste trabalho foi identificar a família Hsp70 de Trichoderma asperellum e analisar a expressão de três genes codificando proteínas desta família durante o micoparasitismo e em situações de estresse térmico e estresse por etanol. A identificação das proteínas Hsp70 de T. asperellum foi possível a partir de análises em banco de dados (JGI) do genoma de Trichoderma asperellum, disponível, mas não anotado. Identificamos no total 12 proteínas da família Hsp70 em T. asperellum, sendo três selecionadas para ensaios de expressão gênica. Foi realizado cultivo pareado entre T. asperellum e os fitopatógenos: Sclerotinia sclerotiorum e Fusarium oxysporum em três fases do micoparasitismo: pré-contato, contato e pós-contato. Verificamos que a expressão dos genes Tahsp70a, Tahsp70b e Tahsp70c varia de acordo com as fases do micoparasitismo e do fitopatógeno estudado. A expressão dos genes hsp70 em estresse térmico, foi avaliada na condição de 38 °C durante 30 minutos, 1, 2 e 4 horas e nas condições de 4, 10 e 32 °C por 1 hora, O estresse por etanol também foi realizado por 1 hora. Durante o estresse térmico, Tahsp70a e Tahsp70b apresentaram maior indução sendo que o gene Tahsp70c teve sua maior indução no choque frio à 4 °C. No estresse por etanol os genes analisados não apresentaram expressão significativa.
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30

Petitjean, Celine. "Phylogénie et évolution des Archaea, une approche phylogénomique." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-01070633.

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En 1977, Carl Woese sépare les procaryotes en deux grands groupes en proposant une nouvelle classification basée sur des critères phylogénétiques. Les Archaea deviennent ainsi un domaine à part entière aux cotés des Bacteria et des Eucarya. Depuis, la compréhension de ce nouveau groupe et de ses relations avec les deux autres domaines, essentielles pour comprendre l'évolution ancienne du vivant, est largement passée par l'étude de leur phylogénie. Presque 40 ans de recherche sur les archées ont permis de faire évoluer leur image : de bactéries vivant dans des milieux spécialisés, souvent extrêmes, on est passé à un domaine indépendant, très diversifié aussi bien génétiquement, métaboliquement ou encore écologiquement. Ces dernières années la barre symbolique de cent génomes complets d'archées séquencés a été franchie et, parallèlement, les projets génomiques et métagénomiques sur des groupes peu caractérisés ou de nouvelles lignées de haut rang taxonomique (e.g. Nanohaloarchaea, Thaumarchaeota, ARMAN, Aigarchaeota, groupe MGC, groupe II des Euryarchaeota, etc.) se sont multipliés. Tout ceci apporte un matériel sans précédent pour l'étude de l'histoire évolutive et de la diversité des Archaea. Les protéines ribosomiques ont été utilisées de façon courante pour inférer la position phylogénétique des nouvelles lignées d'Archaea. Néanmoins, les phylogénies résultantes ne sont pas complètement résolues, laissant des interrogations concernant d'importantes relations de parenté. La recherche de nouveaux marqueurs est donc cruciale et c'est dans ce contexte que mon projet de thèse s'inscrit. À partir de l'analyse des génomes de deux Thaumarchaeota et d'une Aigarchaeota, nous avons identifié 200 protéines conservées et bien représentées dans les différents phyla d'archées. Ces protéines sont impliquées dans de nombreux processus cellulaires, ce qui peut apporter un signal phylogénétique complémentaire à celui des marqueurs de type informationnel utilisés par le passé. En plus de confirmer la plupart des relations phylogénétiques inférées à partir de ces derniers (i.e., protéines ribosomiques et sous unités de l'ARN polymérase), l'analyse phylogénétique de ces nouveaux marqueurs apporte un signal permettant une meilleure résolution de la phylogénie des archées et la clarification de certaines relations jusqu'ici confuses. Un certain nombre de ces nouveaux marqueurs sont aussi présents chez les bactéries. Les relations entre les grands phyla d'archées restant encore non résolues, nous avons utilisé ces protéines pour essayer de placer la racine de l'arbre des Archaea en utilisant comme groupe extérieur les bactéries. Nous avons ainsi pu identifier 38 protéines, parmi les 200 sélectionnées précédemment, ayant un signal phylogénétique suffisamment fiable pour cette étude, auxquelles nous avons ajouté 32 protéines ribosomiques universelles. L'utilisation conjointe de ces données nous a permis de placer la racine entre les Euryarchaeota, d'une part, et un groupe rassemblant les Thaumarchaeota, les Aigarchaeota, les Korarchaeota et les Crenarchaeota, d'autre part. Ce nouvel éclairage sur l'évolution ancienne des archées nous a amené à proposer une révision de leur taxonomie avec, principalement, la création du nouveau phylum "Proteoarchaeota" contenant les quatre phyla actuels que nous proposons de rétrograder en classes : Thaumarchaea, Aigarchaea, Korarchaea et Crenarchaea.Finalement, l'analyse des protéines codées dans les trois génomes qui ont servi de point de départ de ma thèse nous a permis de générer une masse considérable de données qui ont révélé des traits particuliers ou encore des histoires évolutives inattendues. Un exemple est l'histoire du complexe formé par la chaperonne DnaK et de ses co-chaperonnes GrpE, DnaJ, et DnaJ-Fer chez les Thaumarchaeota, impliquant plusieurs transferts horizontaux entre les trois domaines du vivant.
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31

Teske, Anja. "Variations in the human hsp60 gene between cases of sudden infant death syndrome and non-affected children." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976146797.

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32

Billoud, Bernard. "Expression d'un gene hsp70 au cours de l'ovogenese et de l'embryogenese precoce de l'amphibien urodele pleurodeles waltl." Paris 5, 1994. http://www.theses.fr/1994PA05S005.

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Les proteines hsp70 (heat shock protein, 70kd) sont des proteines chaperons hautement conservees au cours de l'evolution, qui sont susceptibles de moduler l'activite de facteurs proteiques directement impliques dans le controle du developpement. Nous avons isole et caracterise la sequence codante complete d'un gene hsp70 de pleurodeles waltl (amphibien, urodele), et etudie son expression dans l'ovocyte et l'embryon de pleurodele en absence de stress. Un arn messager, identique a l'arn hsp70 inductible des cellules somatiques, s'accumule dans l'ovocyte tout au long de l'ovogenese. L'hybridation in situ sur chromosomes en ecouvillon montre que l'ovocyte post-vitellogenique synthetise au moins une partie de l'arn hsp70 stocke. L'ovocyte traduit cet arn en proteine hsp70, qui s'accumule tout au long de l'ovogenese, et est necessaire a la transcription ovocytaire. Dans l'embryon, l'arn hsp70 est transcrit des les stades de segmentation. Hsp70 ne suit donc pas la regle generale selon laquelle l'embryon d'amphibien en cours de segmentation est transcriptionnellement inactif avant la transition mi-blastuleenne.
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33

Gutierrez, Jesus Antonio. "Identification and characterization of the heat shock response and an inducible Hsp70 gene in bovine skeletal muscle." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186695.

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Experiments were conducted to quantify Hsp70 proteins and mRNAs in non-stressed bovine tissues, skeletal muscle undergoing heat shock and during cardiac muscle anoxia. Antibodies that show specificity against the inducible Hsp70 were developed and used in immunofluorescence and quantitative ELISA experiments. Tissue surveys using the ELISA assay demonstrated Hsp70 to be present in all tissues, with skeletal muscle about three fold higher than the other tissues at about 9 ng/μg. Immunofluorescence results in non-stressed ovine skeletal muscle showed Hsp70 to be mostly located in the sarcoplasm and a small but specific staining pattern suggestive of sarcoplasmic reticulum (SR) staining was observed. Skeletal muscle fractionation studies demonstrated about 1% of Hsp70 to be localized in the SR. Skeletal muscle heat shock and cardiac muscle anoxia determined that Hsp70 could be elevated by either of these insults, with heat shock increasing Hsp70 levels about two fold. Temporary cardiac anoxia experiments demonstrated that Hsp70 could be partially increased by initial handling of the heart, but after 3 hours following the release of a complete aortic clamp, Hsp70 levels had increased about four fold over basal levels. A cDNA for bovine skeletal muscle Hsp70 was isolated and used for RNAse protection assays and expression experiments. Results from RNAse protection assays demonstrated the presence of the complete cDNA in all tissues examined with a pattern of expression between tissues similar to Hsp70 protein profiles. Skeletal muscle contained the highest level of Hsp70 mRNA, about three fold higher than brain. Skeletal muscle heat shock experiments demonstrated about a four fold increase in the level of Hsp70 mRNA from 0.4 pg/μg total RNA to about 1.65 pg/μg total RNA. Bacterial expression and purification of the cDNA product demonstrated the recombinant protein to have identical mobility in polyacrylamide gels containing SDS and crossreactivity to Hsp70 antibodies as the inducible Hsp70. Two dimensional gel electrophoresis demonstrated that the recombinant protein encodes a minor isoform in skeletal muscle, and carbamylation of the recombinant protein showed the carbamylated protein to form a train similar to bovine skeletal muscle heat shock protein.
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34

Costa, Marcos Rodrigo Jeronimo da. "Efeito do estresse térmico no relógio biológico de Danio rerio: um elo entre temperatura , luz, canais termoTRPs e genes de relógio." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-07122016-093720/.

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A adaptação temporal é fundamental para a sobrevivência de espécies que precisam coordenar sua fisiologia e comportamentos ajustando-se a sinais externos. Ritmos biológicos não são simplesmente uma resposta às mudanças de 24 horas no ambiente físico impostas pela rotação da Terra sobre o seu próprio eixo, ao contrário, surgem a partir de um sistema de cronometragem endógeno. No teleósteo Danio rerio, ainda não foi identificada a presença de uma região que atue como relógio central; alguns estudos têm evidenciado a existência de células e tecidos que contêm relógios circadianos autônomos, fotossensíveis, comprovando um outro tipo de regulação dos ritmos circadianos onde a percepção do ambiente e o ajuste do período circadiano são efetivados diretamente em nível celular. As consequências deletérias do aumento da temperatura são impedidas, em certa medida, por uma resposta adaptativa que assegura a sobrevivência celular na presença de calor. Esta via de sobrevivência ativada por calor, conhecida como resposta ao choque térmico, é composta por uma cascata de eventos que conduzem à indução de proteínas de choque térmico (HSPs) que minimizam a lesão celular aguda. Acredita-se que os sistemas de percepção dos ciclos diários de temperatura e luminosidade sofreram as mesmas pressões seletivas em sua co-evolução, resultando em sua associação. As bases da sensação térmica estão em um grupo de canais altamente conservados, presente em todos os metazoários estudados até o momento e envolvidos em uma série de modalidades sensoriais, os canais de potencial receptor transiente (TRP); os que respondem a estímulos térmicos foram agrupados em uma subfamília e denominados termoTRPs. O objetivo deste trabalho foi investigar a influência do pulso de temperatura (33 ºC) na expressão de genes de relógio e de proteínas de choque térmico, bem como o papel do canal TRPV1, em células embrionárias de blástula de Danio rerio, denominadas ZEM-2S, submetidas a escuro constante (DD) ou ciclos claro-escuro (LD 12:12). Através de PCR em tempo real (quantitativo) demonstrou-se que as células ZEM-2S expressam os genes dos seguintes canais TRP: trpA1a, trpA1b, trpV1/2, trpV4, trpC6, trpM2, trpM4a, trpM4b/c e trpM5. Após um pulso de temperatura, observou-se um aumento no transcrito de hsp90 aa1 em células mantidas tanto em DD como em LD, sendo a expressão de hsp90 aa1 em LD, no ponto uma hora, duas vezes menor quando comparada a sua expressão no mesmo ponto temporal em DD. O pulso de temperatura não promoveu efeito em nenhum dos genes do relógio estudados (bmal1a, bmal1, bmal2, cry1a, cry1b, per1, per2) quando as células foram mantidas em DD. Porém, o transcrito de per2 aumentou em resposta ao pulso de temperatura quando as células foram sincronizadas pelos ciclos claro-escuro. A inibição do canal TRPV1 não alterou o efeito induzido pelo pulso de temperatura na expressão do gene hsp90 aa1 em células ZEM-2S mantidas em DD. Por outro lado, nossos dados permitem afirmar que o mesmo participa parcialmente na indução do aumento da expressão do gene per2 pelo estímulo térmico em células mantidas em LD, tendo em vista um decaimento significativo na resposta deste gene. Os dados obtidos neste trabalho abrem uma nova perspectiva sobre a investigação da relação temperatura e genes de relógio, colocando um novo “ator” na regulação deste fenômeno: o canal TRPV1
Temporal adaptation is essential for the survival of species which need to coordinately adjust their physiology and behavior to external signals. Biological rhythms are not just a response to the 24 hour changes in the physical environment imposed by the rotation of the Earth around its own axis, but they arise from an endogenous timing system. In the teleost Danio rerio, there has not been identified so far a region in the nervous system that could act as a central clock; some studies have reported the existence of cells and tissues which contain photosensitive, autonomous circadian clocks, demonstrating the existence of another type of circadian rhythm regulation in which environment perception and entrainment of the circadian period are directly effected at cell level. The deleterious consequences of temperature increase are prevented by an adaptive response which assures cell survival in the presence of heat. This survival pathway activated by heat, known as response to temperature shock, is signaled by a cascade of events leading to the induction of thermal shock proteins (HSPs) which attenuate the acute cell lesion. It is believed that the systems perceiving temperature and light daily cycles were subject to the same selective pressures during their co-evolution, resulting in their association. The base of thermal sensation is a family of highly conserved channels, present in all metazoans studied to date, and involved in a variety of sensorial modalities, the transient receptor potential channels (TRP); those responding to thermal stimuli were grouped in a sub-family named thermo-TRPs. The aim of this work was to investigate the influence of a temperature pulse (33 ºC) on the expression of clock and heat shock protein genes, as well as the role of TRPV1 channel, in blastula embryonic cells of Danio rerio, named ZEM-2S, subject to constant dark (DD) or light-dark cycles (LD). Using quantitative PCR, we demonstrated that ZEM-2S cells express genes for the following TRP channels: trpA1a, trpA1b, trpV1/2, trpV4, trpC6, trpM2, trpM4a, trpM4b/c and trpM5. After the pulse of temperature, we observed an increase of hsp90 aa1 transcripts in DD as well as in LD; hsp90 aa1 expression 1 hour after the stimulus was two-fold lower in LD than in DD. Temperature pulse did not affect the expression of any of the studied clock genes (bmal1a, bmal1, bmal2, cry1a, cry1b, per1, per2), when the cells were kept in DD. However, per2 transcript increased in response to the temperature pulse when the cells were synchronized by light-dark cycles. Inhibition of TRPV1 channel did not change the effect induced by the temperature pulse on hsp90 aa1 in ZEM-2S cells kept in DD. On the other hand, our data suggest that this channel participates, at least partially, in the temperature-induced increase of per2 in cells maintained in LD, as indicated by the significant decay observed in the gene response in the presence of the inhibitor. Our results open new investigative perspective about the relationship between temperature and clock genes, placing a new “actor” in the regulation of the phenomenon: the TRPV1 channel
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35

Maugeri, Narelle. "Effects of single nucleotide polymorphisms on the expression of HSP70 genes, HSPA1A and HSPA1B." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531979.

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36

Hagemeier, Christian. "Transactivation of the hsp70 gene and protooncogenes c-fos and c-myc by human cytomegalovirus immediate early proteins." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316643.

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37

Ferreira, Júnior Augusto Luiz. "Análise de polimorfismos de nucleotídeos únicos (SNPs) do gene HSP70 em populações de litopenaeus vannamei comercializadas no Brasil." reponame:Repositório Institucional da UFSC, 2014. https://repositorio.ufsc.br/xmlui/handle/123456789/128925.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Aqüicultura, Florianópolis, 2014.
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O objetivo do trabalho foi estudar a diversidade genética do gene HSP70 através da análise de SNPs em três populações (LV A, LV B e LV C) de Litopenaeus vannamei comercializadas no Brasil e verificar se existe associação entre seus genótipos e a tolerância ao vírus da síndrome da mancha branca. (WSSV). Um desafio viral foi efetuado com a população LV B (nunca exposta à doença viral). O fragmento (posição 475 a 1594) do gene HSP70 foi amplificado em PCR com os iniciadores específicos. Neste estudo utilizou-se 5 SNPs (C661A, T712C, C782T, C892T e C1090T) presentes nas três populações. As heterozigozidades (Ho e He) foram menores nas populações LV A e LV B (sem controle de pedigree) comparadas com LV C (com melhoramento genético de resistência a vírus). O FIS indicou que as populações LV A e LV B possuem maiores coeficientes endogamia (4,5 e 5,0 x maiores, respectivamente) comparadas com a população LV C. Houve uma baixa divergência gênica (FST: 0,042; GST: 0,031) e diferenças entre as populações (p<0,05). Uma baixa distância genética (NeiD) foi observada entre as populações, com diferença fenotípicas (p<0,05) no SNP C892T entre as populações sem controle de pedigree (LVA e LV B) e a população com melhoramento genético de resistência viral (LV C). No desafio viral não se observou diferenças entre os genótipos e a tolerância ao WSSV, mas com um aumento da frequência no alelo T do SNP C892T. Podemos concluir que existem pequenas diferenças entre as três populações cultivadas no Brasil e uma possível relação do SNPs C892T a doenças virais.

Abstract : This work was aimed at studying the genetic diversity of HSP70 gene by analyzing SNPs in three Litopenaeus vannamei populations (LV A, LV B and LV C) marketed in Brazil and investigating whether its genotypes are somehow associated to tolerance to the white spot syndrome virus (WSSV). A viral challenge was carried out with the LV B population (never subjected to the viral disease). A fragment (position 475 to 1594) of the HSP70 gene was PCR amplified with specific primers. In this study we used 5 SNPs (C661A, T712C, C782T, C892T and C1090T) present in three populations. Heterozygosities (Ho and He) were lower in the populations LV A and LV B (no pedigree control) when compared with LV C (with breeding for virus resistance). FIS has revealed that the populations LV A and LV B have higher inbreeding coefficients (4.5 and 5.0 x higher, respectively) when compared with LV C. There have been low genetic divergence (FST: 0.042; GST: 0.031) and differences between populations (p<0.05). Low genetic distance (NeiD) was observed amongst populations and there were phenotypic differences (p<0.05) in the SNP C892T of populations without pedigree control (LVA and LV B) and that subjected to breeding for viral resistance (LV C). In viral challenge there were no differences between the genotypes and tolerance to WSSV, but the T allele frequency was seen to have increased in SNP C892T. We can therefore conclude that there are small differences between the three populations grown in Brazil, as well as a possible association of C892T SNPs with viral diseases.
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38

Prudhomme, Christelle. "Expression d'un gène hsp70 au cours de l'ovogenèse et de l'embryogenèse précoce de l'amphibien urodèle pleurodèles Waltl après un traitement hyperthermique." Paris 5, 1997. http://www.theses.fr/1997PA05S007.

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Nous avons déterminé les conditions de choc thermique induisant une réponse heat-shock dans l'ovocyte et l'embryon de pleurodèle. Cette réponse dépend de trois facteurs : la température, la durée du choc et le temps de récupération. Au cours de l'ovogenèse, nous avons mis en évidence une réponse au stress qui se traduit par une augmentation de la quantité des transcrits hsp70 par rapport aux contrôles. Cette augmentation est corrélée à une surexpression des synthèses d'hsp70 mais pas à une augmentation de la quantité globale d'hsp70. La régulation de l'expression du gène hsp70 se fait aux niveaux transcriptionnelle et traductionnel. La répartition nucléocytoplasmique de la protéine hsp70 en conditions normales, mis en évidence par immunocytochimie, montre une localisation préférentielle de celle-ci sur la membrane plasmique, dans la région perinucleaire ainsi que dans certains noyaux d'ovocytes de stade vi. Cette répartition ne varie pas en conditions de choc. Lors du développement embryonnaire, un choc hyperthermique induit une augmentation de la quantité D'ARNM hsp70 et des synthèses de la protéine uniquement à partir du stade de la gastrula. La régulation de l'expression du gène HSP70 est corrélée a la mise en route du génome zygotique. Dans l'embryon, la protéine HSP70 est localisée préférentiellement au niveau de la membrane plasmique et dans les noyaux des cellules en cours d'internalisation ; aucune variation n'est observée après un choc thermique. Nous nous sommes intéressés au transfert nucléaire de la protéine dans les cellules internalisées au stade de la gastrula en conditions normales. L'utilisation d'inhibiteurs de la réplication et de la transcription au stade de la gastrula a montré que la protéine était impliquée dans ces phénomènes. Ces résultats nous ont conduits à discuter de la régulation de l'expression du gène HSP70 en conditions de stress au cours du développement et de son rôle potentiel au cours du cycle cellulaire dans les conditions normales.
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39

Dobbs, Edward. "Investigation of the role of essential proteins in gene silencing at the centromere of Schizosaccharomyces pombe." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7690.

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The centromeres of eukaryotes have a region on which the kinetochore is assembled, flanked by heterochromatin which provides cohesion between the sister chromatids during cell division. When centromeric heterochromatin is lost chromosomes no longer segregate evenly into the daughter cells during cell division. In the fission yeast Schizosaccharomyces pombe (S. pombe) RNA interference (RNAi) is responsible for maintaining this heterochromatin. The pathway is part of a feedback loop whereby siRNAs generated from non-coding centromere transcripts are loaded into an Argonaute complex. The siRNAs guide the complex to the homologous centromere repeats in order to recruit Clr4 which modifies histone H3 with the heterochromatin mark H3K9me. A previous screen to find factors affecting centromere silencing isolated 13 loci termed centromere: suppressor of position-effect (csp) 1-13. Several csp mutants have been identified to be RNAi components. In this investigation the csp6 locus has been identified to be the Hsp70 gene ssa2+. It has been demonstrated that Argonaute proteins from plants and flies require Hsp70/90 chaperone activity for loading of siRNA. It therefore seems likely that Hsp70 may play a similar role in fission yeast. Genetic and biochemical techniques have been used in this study to investigate if the csp6 alleles are affecting siRNA loading in S. pombe. RNA Polymerase II (RNAPII) transcribes the pre-siRNA transcripts from the centromere repeats. csp3 was identified to be an allele of the RNAPII subunit rpb7+. rpb7-G150D was found to cause a silencing defect in the centromeric heterochromatin through a defect in transcription. Another RNAPII mutation, rpb2-m203, was found to have strong silencing defects caused by an unidentified non-transcriptional role in RNAi-mediated heterochromatin formation at the centromere. In order to gain more insight into the role of RNAPII in heterochromatin assembly I performed a screen in which the subunits rpb3 and rpb11 were subjected to random mutagenesis. Several mutants were isolated and characterisation of phenotypes regarding heterochromatin at the centromere has been carried out for nine of the mutants. As a result a novel phenomenon of RNAi-independent silencing at the centromere has been discovered.
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40

Vasconcelos, Oliveira Silva Sandra. "Mapeamento por hibridização in situ dos genes Lys Hsp70 e Hsp83 nos cromossomos meióticos do gafanhoto Schistocerca pallens (ACRIDIDAE)." Universidade Federal de Pernambuco, 2004. https://repositorio.ufpe.br/handle/123456789/6715.

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Algumas espécies de gafanhotos são pragas milenares de áreas cultivadas em diversas regiões do mundo, provocando grandes prejuízos econômicos e ecológicos em períodos de explosão populacional. No Brasil, as espécies mais ameaçadoras, que causam danos significativos às lavouras e pastagens, são Rhammatocerus schistocercoides, Stiphra robusta e Schistocerca pallens, nenhuma das quais foi geneticamente bem caracterizada, apesar da grande importância prática. Neste trabalho foi iniciada a caracterização genética de S. pallens, através da localização por hibridização in situ dos genes Lys, Hsp70 e Hsp83 em cromossomos meióticos. Aproximadamente 700 núcleos foram analisados para os três genes e o percentual médio de marcação foi de 68,49%. Após análise de 108 núcleos marcados, com uma freqüência de 94,44% o gene Lys foi mapeado no cromossomo G1. O gene Hsp70 foi mapeado no cromossomo G2, onde foram observadas 89,94% das marcações do total de 199 núcleos marcados. Para o loco Hsp83 foram contados 163 núcleos marcados, dos quais 97,54% das marcações foram localizadas em um cromossomo médio identificado como M7. Para todos os genes hibridizados outras marcações foram observadas, mas todas em freqüências inferiores a 30%. Estes são os primeiros genes mapeados em S. pallens, sendo também os primeiros genes de cópia única mapeados na família Acrididae. Além de servir como novos marcadores para individualização cromossômica, os dados da localização destes genes poderão ser úteis como marcas físicas para um eventual programa de seqüenciamento genômico da espécie
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41

Benavides, Luis Evert Enriquez [UNESP]. "Indicadores fisiológicos de estresse e expressão do gene hsp70 em juvenis do Pacu (Piaractus mesopotamicus) após implante de cortisol." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/86485.

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Quando as células de um organismo são expostas a um estressor, elas respondem sintetizando um grupo de proteínas denominadas proteínas de choque térmico (heat shock proteins - hsp), agrupadas em quatro famílias: hsp-90, hsp-70, hsp-60 e pequenas hsp's, sendo a família das hsp-70 a mais conservada e filogeneticamente ubíqua, e que tem sido considerada indicador molecular da resposta de estresse. O objetivo deste estudo foi caracterizar as respostas fisiológicas e moleculares de pacus (Piaractus mesopotamicus) submetidos à elevação exógena do cortisol, utilizando a expressão do gene da hsp-70 como ferramenta de determinação da resposta molecular. Um total de 104 peixes (67,5±11,7 g) recebeu implantes intraperitoniais de manteiga de cacau contendo 0, 50 e 100 μg cortisol /g de peso vivo, e foi amostrado 1, 3, 6 e 24 horas após o implante, para determinação das concentrações séricas de cortisol, sódio e potássio e plasmáticas de glicose e cloreto. Um grupo foi amostrado antes do implante (grupo basal). Para a expressão gênica foram analisados o grupo basal e o injetado com 50 μg cortisol/g. O cortisol circulante aumentou a partir de 1 hora após o implante dos péletes contendo cortisol e se manteve alto até 24 horas depois. A resposta da glicose circulante acompanhou as elevações do cortisol no sangue, confirmando sua ação gliconeogênica, porém houve ausência de respostas nos indicadores iônicos. A expressão do gene hsp70 do pacu mostrou leve aumento 3 e 6 horas após o implante, mas foi mais expressiva 24 horas depois, indicando a possibilidade do uso da expressão gênica da hsp70 como marcador de elevação dos níveis de cortisol e da resposta de estresse
When the cells of an organism are exposed to a stressor, they respond by synthesizing a group of proteins called heat shock proteins (hsp), which are grouped into four families: Hsp-90, Hsp-70, Hsp-60 and small hsp's, where the family of Hsp-70 is the most conserved and phylogenetically ubiquitous, and has been considered an indicator of molecular stress response. The aim of this study was to characterize the molecular and physiological responses of pacu (Piaractus mesopotamicus) to elevation exogenous cortisol, using gene expression of hsp-70 as a tool for determining the molecular response. A total of 104 fish (67.5 ± 11.7 g) received intraperitoneal implants of cocoa butter containing 0, 50 and 100 mg cortisol / g of live weight and were sampled 1, 3, 6 and 24 hours after implantation for determination of serum cortisol, sodium and potassium and plasma glucose and chloride. One group was sampled before implantation (baseline group). For gene expression were analyzed the baseline group and the injected with 50 mg cortisol / g. The cortisol increased from 1 hour after implantation of pellets containing cortisol and remained high until 24 hours later. The response of circulating glucose followed elevations of cortisol in the blood, confirming gluconeogenic action, but there were no responses in ion indicators. The expression of the hsp70 gene showed slight increase 3 and 6 hours after implantation, but was more pronounced after 24 hours, indicating the possibility of using gene expression of hsp70 as a marker of increased levels of cortisol and stress response
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42

Benavides, Luis Evert Enriquez. "Indicadores fisiológicos de estresse e expressão do gene hsp70 em juvenis do Pacu (Piaractus mesopotamicus) após implante de cortisol /." Jaboticabal, 2013. http://hdl.handle.net/11449/86485.

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Orientador: Elisabeth Criscuolo Urbinati
Coorientador: Flávia Maria de Souza Carvalho
Banca: Marisa Narciso Fernandes
Banca: Luiz Roberto Furlan
Resumo: Quando as células de um organismo são expostas a um estressor, elas respondem sintetizando um grupo de proteínas denominadas proteínas de choque térmico (heat shock proteins - hsp), agrupadas em quatro famílias: hsp-90, hsp-70, hsp-60 e pequenas hsp's, sendo a família das hsp-70 a mais conservada e filogeneticamente ubíqua, e que tem sido considerada indicador molecular da resposta de estresse. O objetivo deste estudo foi caracterizar as respostas fisiológicas e moleculares de pacus (Piaractus mesopotamicus) submetidos à elevação exógena do cortisol, utilizando a expressão do gene da hsp-70 como ferramenta de determinação da resposta molecular. Um total de 104 peixes (67,5±11,7 g) recebeu implantes intraperitoniais de manteiga de cacau contendo 0, 50 e 100 μg cortisol /g de peso vivo, e foi amostrado 1, 3, 6 e 24 horas após o implante, para determinação das concentrações séricas de cortisol, sódio e potássio e plasmáticas de glicose e cloreto. Um grupo foi amostrado antes do implante (grupo basal). Para a expressão gênica foram analisados o grupo basal e o injetado com 50 μg cortisol/g. O cortisol circulante aumentou a partir de 1 hora após o implante dos péletes contendo cortisol e se manteve alto até 24 horas depois. A resposta da glicose circulante acompanhou as elevações do cortisol no sangue, confirmando sua ação gliconeogênica, porém houve ausência de respostas nos indicadores iônicos. A expressão do gene hsp70 do pacu mostrou leve aumento 3 e 6 horas após o implante, mas foi mais expressiva 24 horas depois, indicando a possibilidade do uso da expressão gênica da hsp70 como marcador de elevação dos níveis de cortisol e da resposta de estresse
Abstract: When the cells of an organism are exposed to a stressor, they respond by synthesizing a group of proteins called heat shock proteins (hsp), which are grouped into four families: Hsp-90, Hsp-70, Hsp-60 and small hsp's, where the family of Hsp-70 is the most conserved and phylogenetically ubiquitous, and has been considered an indicator of molecular stress response. The aim of this study was to characterize the molecular and physiological responses of pacu (Piaractus mesopotamicus) to elevation exogenous cortisol, using gene expression of hsp-70 as a tool for determining the molecular response. A total of 104 fish (67.5 ± 11.7 g) received intraperitoneal implants of cocoa butter containing 0, 50 and 100 mg cortisol / g of live weight and were sampled 1, 3, 6 and 24 hours after implantation for determination of serum cortisol, sodium and potassium and plasma glucose and chloride. One group was sampled before implantation (baseline group). For gene expression were analyzed the baseline group and the injected with 50 mg cortisol / g. The cortisol increased from 1 hour after implantation of pellets containing cortisol and remained high until 24 hours later. The response of circulating glucose followed elevations of cortisol in the blood, confirming gluconeogenic action, but there were no responses in ion indicators. The expression of the hsp70 gene showed slight increase 3 and 6 hours after implantation, but was more pronounced after 24 hours, indicating the possibility of using gene expression of hsp70 as a marker of increased levels of cortisol and stress response
Mestre
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43

Boulangé, Alain-François. "Clonage et expression des gènes codant pour une HSP70/BIP et une cystéineprotéase de trypanosoma congolense : utilisation de ces antigènes dans l'étude de la trypanotolérance bovine." Bordeaux 2, 1995. http://www.theses.fr/1995BOR28361.

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44

Poli, Davide. "Gene expression responses to acute and chronic heat stress in the common reef-building coral Pocillopora verrucosa." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8326/.

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Global climate change is impacting coral reefs worldwide, with approximately 19% of reefs being permanently degraded, 15% showing symptoms of imminent collapse, and 20% at risk of becoming critically affected in the next few decades. This alarming level of reef degradation is mainly due to an increase in frequency and intensity of natural and anthropogenic disturbances. Recent evidence has called into question whether corals have the capacity to acclimatize or adapt to climate changes and some groups of corals showed inherent physiological tolerance to environmental stressors. The aim of the present study was to evaluate mRNA expression patterns underlying differences in thermal tolerance in specimen of the common reef-building coral Pocillopora verrucosa collected at different locations in Bangka Island waters (North Sulawesi, Indonesia). Part of the experimental work was carried out at the CoralEye Reef Research Outpost (Bangka Island). This includes sampling of corals at selected sites and at different depths (3 and 12 m) as well as their experimental exposure to an increased water temperature under controlled conditions for 3 and 7 days. Levels of mRNAs encoding ATP synthase (ATPs) NADH dehydrogenase (NDH) and a 70kDa Heat Shock Protein (HSP70) were evaluated by quantitative real time PCR. Transcriptional profiles evaluated under field conditions suggested an adaptation to peculiar local environmental conditions in corals collected at different sites and at the low depth. Nevertheless, high–depth collected corals showed a less pronounced site-to-site separation suggesting more homogenous environmental conditions. Exposure to an elevated temperature under controlled conditions pointed out that corals adapted to the high depth are more sensitive to the effects of thermal stress, so that reacted to thermal challenge by significantly over-expressing the selected gene products. Being continuously exposed to fluctuating environmental conditions, low-depth adapted corals are more resilient to the stress stimulus, and indeed showed unaffected or down-regulated mRNA expression profiles. Overall these results highlight that transcriptional profiles of selected genes involved in cellular stress response are modulated by natural seasonal temperature changes in P. verrucosa. Moreover, specimens living in more variable habitats (low-depth) exhibit higher basal HSP70 mRNA levels, possibly enhancing physiological tolerance to environmental stressors.
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45

Sessa, Thor Andreas Silva Di. "Terapia gênica na paracoccidioidomicose experimental utilizando vetor de expressão de HSP60 E mIL-12." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5133/tde-20022014-114721/.

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A paracoccidioidomicose (PCM) é uma doença sistêmica de caráter granulomatoso, causada pelo fungo termodimórfico Paracoccidioides spp. A PCM é endêmica na America Latina e aproximadamente 80% do pacientes vivem no território brasileiro. O tratamento medicamentoso é eficiente, entretanto, é longo e vários pacientes acabam abandonando e recidivas são comuns neste grupo. A utilização de uma vacina terapêutica poderia resultar na redução do tempo de tratamento assim como, recuperar a resposta imune do hospedeiro frente ao fungo. As vacinas de DNA são uma abordagem promissora na imunoterapia e podem ser injetadas por via intramuscular, intradérmica ou via mucosa. As proteínas de choque térmico (HSPs) são proteínas que estão ligadas a homeostase celular e também possuem efeitos imunológicos em diversos casos como doenças infecciosas e autoimunes. No presente trabalho, analisamos o esquema vacinal terapêutico em camundongos BALB/c previamente infectados intratraquealmente com 3x105 leveduras de P. brasiliensis Pb18, 60 dias depois, submetidos a imunização com pcDNA3 contendo sequências codificadoras de PbHSP60 e/ou IL-12 murina e/ou vetor vazio. Foi observada redução significativa no número de unidades formadoras de colônia (UFCs) nos pulmões de camundongos imunizados com PbHSP60. Os grupos que receberam PbHSP60+pcDNA3 vazio ou PbHSP60x2 apresentaram os maiores índices de redução da cargas fúngicas. A inclusão do plasmídeo contendo o inserto de mIL-12, resultou em um efeito deletério. A análise dos cortes histológicos indicou que os animais vacinados apresentavam áreas bem preservadas e com poucos ou nenhum foco de granuloma. Detectamos um perfil de citocinas típico Th1/Th2. Nossos resultados sugerem que a imunização utilizando plasmídeo contendo o inserto HSP60, tem grande potencial vacinal
The paracoccidioidomycosis (PCM) is a systemic granulomatous disease of character, caused by the thermally dimorphic fungus Paracoccidioides spp. The PCM is endemic in Latin America and approximately 80% of patients are living in Brazil. The medical treatment is effective, however, is long and many patients end up abandoning and relapses are common in this group.The use of a therapeutic vaccine could result in the reducing time of treatment as well as recover the host immune response against the fungus. DNA vaccines are a promising approach for immunotherapy and can be injected by intramuscular, intradermal, or mucosal route. The heat shock proteins (HSPs) are proteins that are linked to cellular homeostasis and also have immunological effects in many cases as infectious and autoimmune diseases. In the present study, we analyzed the therapeutic vaccine schedule in BALB/c mice previously infected intratracheally with 3x105 yeast of P. brasiliensis strain 18, and 60 days after, undergoing immunization with pcDNA3 containing coding sequences PbHSP60 and / or murine IL-12 and / or empty vector. Significant reduction was observed in the number of colony forming units (CFU) in the lungs of mice immunized with PbHSP60. The groups that received empty pcDNA3 and PbHSP60 or PbHSP60x2 have higher rates of reduced fungal loads. The inclusion of the plasmid containing the insert mIL-12 resulted in a deleterious effect. The analysis of histological sections indicated that vaccinated animals had wellpreserved, with few or no focus of granuloma areas. It was detected a profile typical Th1/Th2 cytokines. Our results suggest that immunization using plasmid containing the insert HSP60 vaccine has great potential
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46

Theodoro, Raquel Cordeiro [UNESP]. "Caracterização da transição micélio-levedura em Paracoccidioides brasiliensis e sua relação com a expressão do gene do choque térmico 70(HSP70)." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/92471.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O fungo termo dimórfico, Paracoccidioides brasiliensis é o agente etiológico da Paracoccidioidomicose (PCM), a micose sistêmica mais prevalente da América Latina. Este fungo vem sendo frequentemente isolado de amostras clínicas, tecidos de tatu (Dasypus novemcinctus) e recentemente foi também isolado de cão. Este trabalho avaliou a transição de micélio para levedura (M-L), a termo tolerância e o perfil de virulência em nove isolados de P. brasiliensis (quatro de pacientes humanos, quatro de tatus e um de cão), bem como a sua relação com a seqüência parcial e expressão do gene hsp70 (Heat Shock Protein 70) através de Real Time RT-PCR. Tanto os dados morfológicos como moleculares se mostraram variáveis dentre os diferentes isolados. Alguns destes dados, como sequenciamento e morfologia leveduriforme corroboram com a divisão de nossos isolados nas duas espécies crípticas simpátricas previamente propostas por Matute et al (2006). Nossos resultados confirmam que a HSP70 pode ser um importante fator de virulência por estar associado à termo tolerância, mas sua expressão parece não ser diretamente associada a altos padrões de virulência.
The thermo dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of Paracoccidioidomycosis (PCM), the most prevalent systemic mycosis in Latin America. The previous phylogenetic species recognition proved the existence of, at least, three cryptic species in this pathogen. In this work we evaluated the mycelia to yeast (M-Y) transition, thermo tolerance and virulence profiles of nine isolates of P. brasiliensis, (including members of two of the three species) as well as its relation to the partial sequence and expression of hsp70 gene. It was observed a large phenotypic variability concerning the M-Y transition. The isolates Bt84 and T10 took more time to convert to the yeast form. These same isolates presented stretched yeast cells at 36°C, instead of the typical round cells. It was also observed arthroconidia production during the M-Y transition for some of the nine isolates studied. The hsp70 expression showed to be variable among our isolates. The partial sequencing of hsp70 gene resulted in a Neighbour Joining tree that divided our isolates in two main groups. Our data confirm that hsp70 gene might be an important virulence factor, associated with the thermo tolerance, but its expression does not seem to be directly related to high virulence profiles. We also presented some preliminary results about mycological characters that could be important candidates for morphologic markers for species recognition, as well as the partial sequencing of one member of the hsp70 gene family that allowed the separation of our isolates in two clusters, that correspond to the two sympatric cryptic species that occur in our PCM hyper endemic area (Botucatu, SP, Brazil).
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47

Theodoro, Raquel Cordeiro. "Caracterização da transição micélio-levedura em Paracoccidioides brasiliensis e sua relação com a expressão do gene do choque térmico 70(HSP70) /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/92471.

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Resumo: O fungo termo dimórfico, Paracoccidioides brasiliensis é o agente etiológico da Paracoccidioidomicose (PCM), a micose sistêmica mais prevalente da América Latina. Este fungo vem sendo frequentemente isolado de amostras clínicas, tecidos de tatu (Dasypus novemcinctus) e recentemente foi também isolado de cão. Este trabalho avaliou a transição de micélio para levedura (M-L), a termo tolerância e o perfil de virulência em nove isolados de P. brasiliensis (quatro de pacientes humanos, quatro de tatus e um de cão), bem como a sua relação com a seqüência parcial e expressão do gene hsp70 (Heat Shock Protein 70) através de Real Time RT-PCR. Tanto os dados morfológicos como moleculares se mostraram variáveis dentre os diferentes isolados. Alguns destes dados, como sequenciamento e morfologia leveduriforme corroboram com a divisão de nossos isolados nas duas espécies crípticas simpátricas previamente propostas por Matute et al (2006). Nossos resultados confirmam que a HSP70 pode ser um importante fator de virulência por estar associado à termo tolerância, mas sua expressão parece não ser diretamente associada a altos padrões de virulência.
Abstract: The thermo dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of Paracoccidioidomycosis (PCM), the most prevalent systemic mycosis in Latin America. The previous phylogenetic species recognition proved the existence of, at least, three cryptic species in this pathogen. In this work we evaluated the mycelia to yeast (M-Y) transition, thermo tolerance and virulence profiles of nine isolates of P. brasiliensis, (including members of two of the three species) as well as its relation to the partial sequence and expression of hsp70 gene. It was observed a large phenotypic variability concerning the M-Y transition. The isolates Bt84 and T10 took more time to convert to the yeast form. These same isolates presented stretched yeast cells at 36°C, instead of the typical round cells. It was also observed arthroconidia production during the M-Y transition for some of the nine isolates studied. The hsp70 expression showed to be variable among our isolates. The partial sequencing of hsp70 gene resulted in a Neighbour Joining tree that divided our isolates in two main groups. Our data confirm that hsp70 gene might be an important virulence factor, associated with the thermo tolerance, but its expression does not seem to be directly related to high virulence profiles. We also presented some preliminary results about mycological characters that could be important candidates for morphologic markers for species recognition, as well as the partial sequencing of one member of the hsp70 gene family that allowed the separation of our isolates in two clusters, that correspond to the two sympatric cryptic species that occur in our PCM hyper endemic area (Botucatu, SP, Brazil).
Orientador: Eduardo Bagagli
Coorientador: Ivan de Godoy Maia
Banca: Everaldo dos Reis Marques
Banca: Maria Terezinha Serrão Peraçoli
Mestre
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48

Nogueira, Luiz Fagner Ferreira. "Análise do SNP C892T do gene HSP70 como marcador de resistência do camarão Litopenaeus vannamei ao vírus da mionecrose infecciosa - IMNV." reponame:Repositório Institucional da UFC, 2016. http://www.repositorio.ufc.br/handle/riufc/17883.

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NOGUEIRA, L. F. F. Análise do SNP C892T do gene HSP70 como marcador de resistência do camarão Litopenaeus vannamei ao vírus da mionecrose infecciosa - IMNV. 2016. 49 f. Dissertação (Mestrado em Ciências Marinhas Tropicias) - Instituto de Ciências do Mar, Universidade Federal do Ceará, Fortaleza, 2016.
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This study assessed the C892T polymorphism of the HSP70 gene in two Litopenaeus vannamei strains regarding resistance/susceptibility to infectious myonecrosis, using allelic discrimination through real-time PCR. Post-larvae from two strains of shrimp, one selected for growth (L.C) and one selected for resistance to infectious myonecrosis virus (L.R) were obtained from two commercial hatcheries. At the end of the growth period, it was observed that L.C achieved a higher average weekly growth rate compared to L.R (1.18 g / week and 0.97g / week, respectively). However, under experimental challenge, L.R obtained a better performance against exposure to the virus, reaching the 30th day post infection with 13% survival, while L.C reached 100% mortality at 12 days post injection. The evolution of viral load was similar in both strains. Shrimp categorized as susceptible presented 103 to 105 IMNV copies/μg RNA, while shrimp considered resistant presented 106 to 107 viral copies/ μg RNA. In contrast to what could be expected, allele T of the SNP C892T, which was previously associated with viral resistance, was less frequent in L.R than in L.C. However, its frequency was higher in the resistant group of each lineage. This may be associated with lower genetic variability found in L.R when compared to L.C. The allelic discrimination assay through qPCR allowed successful genotyping for this research showing that SNP C892T is associated with resistance groups / susceptibility to infectious myonecrosis virus. This evidence supports the hypothesis of interaction of this marker with viral diseases present in aquaculture and its potential application in selection programs of shrimp strains resistant to specific pathogens.
Este estudo avaliou o polimorfismo C892T do gene HSP70 em duas linhagens de camarão Litopenaeus vannamei em relação à resistência/susceptibilidade ao vírus na mionecrose infecciosa (IMNV) por meio de ensaio de discriminação alélica por PCR em tempo real. Pós-larvas de duas linhagens de camarões, uma selecionada para o crescimento (L.C) e outra para a resistência ao vírus da mionecrose infecciosa (L.R) foram obtidas de duas empresas especializadas. No final do período de crescimento, observou-se que L.C obteve uma maior taxa de crescimento semanal média em relação a L.R (1,18 g/semana e 0,97g/semana, respectivamente). Sob desafio experimental, a evolução da carga viral foi similar entre os grupos infectados das duas linhagens. Os grupos selecionados como susceptíveis de ambas as linhagens apresentaram uma carga viral entre 103 e 105 cópias do IMNV/μg de RNA, enquanto os grupos resistentes exibiram carga viral entre 106 e 107 cópias. L.R obteve um melhor desempenho frente a exposição ao vírus, chegando ao 30° dia pós injeção do inóculo viral com 13% de sobrevivência, enquanto L.C atingiu 100% de mortalidade ao 12º dia pós injeção. Ao contrário do que poderia ser esperado, o alelo T do SNP C892T, que foi previamente associado à resistência, não foi mais frequente em L.R. Porém, sua frequência foi mais elevada nos grupos de resistência de cada linhagem. Isso pode estar associado à baixa variabilidade genética encontrada em L.R em relação a L.C. O ensaio de discriminação alélica por qPCR possibilitou a obtenção de genótipos para esta pesquisa mostrando que o SNP C892T está associado aos grupos de resistência/suscetibilidade ao vírus da mionecrose infecciosa. Esta evidência reforça a hipótese de interação deste marcador com doenças virais presentes na aquicultura, e sua potencial aplicação em programas de seleção de linhagens resistentes a patógenos específicos.
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49

Regnacq, Matthieu. "Etude d'un nouveau gène heat shock dont l'expression est associée à l'entrée en phase stationnaire chez la levure saccharomyces cerevisiae : le gène HSP30." Bordeaux 2, 1992. http://www.theses.fr/1992BOR28213.

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50

Doldur, Fusun. "Heat Shock Response In Thermoplasma Volcanium: Cloning And Differential Expression Of Molecular Chaperonin (thermosome) Genes." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12610169/index.pdf.

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Abstract:
Chaperonins (Hsp60 chaperones) comprise a class of oligomeric, high-molecular-weight chaperones that have the unique ability to fold some proteins that cannot be folded by simpler chaperone systems. The term &ldquo
thermosome&rdquo
is used for molecular chaperonins from Archaeal organisms since they accumulate to high levels upon heat-shock. In this study first time, we have cloned and sequenced two Hsp60 subunit genes (&
#945
and &
#946
) from a thermoacidophilic archaeon Thermoplasma volcanium. For cloning we have followed a PCR based strategy. Amplification of Hsp60 &
#945
gene from chromosomal DNA of T. volcanium yielded a product of 1939 bp amplicon and that of Hsp60 &
#946
gene yielded a product of 1921 bp amplicon. After ligation of the PCR fragments to pDrive vector, recombinant plasmids were transferred into E. coli TG-1 competent cells and recombinant colonies were selected by blue/white screening. The cloning of two subunit genes were confirmed by restriction mapping and by sequencing. Both subunit genes were then subcloned to pUC18 vector consequtively to construct a co-expression vector. Both subunit genes were expressed under control of their own promoters leading to production of active Hsp60 chaperonin (thermosome). Chaperone activity of the recombinant thermosome was shown by using pig citrate synthase enzyme as substrate. Thermosome induced refolding was observed when renaturation was carried out at 50°
C for 2,5 h. Under this condition, citrate synthase activities associated with control and test were &
#61508
mA412/min:19.0 and &
#61508
mA412/min:24.0 respectively. Clustal W Version 1.82 was used for multiple sequence alignments of Hsp60 &
#61537
and Hsp60 &
#61538
proteins of T. volcanium and other Hsp60 proteins from various eukaryotes, bacteria and archaea. The highest sequence similarity was found between &
#945
subunit proteins of T. volcanium and T. acidophilum (94%) and &
#946
subunit proteins of T. volcanium and T. acidophilum (93%). Clusters of orthologous groups and conserved domain database searches revealed the phylogenetic relationships between Hsp60 &
#61537
and Hsp60 &
#61538
subunits of T. volcanium thermosome and other Hsp60 proteins from various eukaryotes, bacteria and archaea. Induction of both subunit genes under heat shock (65°
C, 70°
C and 75°
C for 2h) and under oxidative stress (imposed by 0,008 mM, 0,01 mM, 0,02 mM, 0,03 mM and 0,05 mM H2O2) conditions was studied by Real-Time PCR technique and amplified cDNA band density analysis.
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