Letteratura scientifica selezionata sul tema "Immunity-Related genes"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Immunity-Related genes".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Articoli di riviste sul tema "Immunity-Related genes":
1
Christophides, George K., Evgeny Zdobnov, Carolina Barillas-Mury, Ewan Birney, Stephanie Blandin, Claudia Blass, Paul T. Brey et al. "Immunity-Related Genes and Gene Families inAnopheles gambiae". Science 298, n. 5591 (4 ottobre 2002): 159–65. http://dx.doi.org/10.1126/science.1077136.
2
Trowsdale, John, e Peter Parham. "Mini-review: Defense strategies and immunity-related genes". European Journal of Immunology 34, n. 1 (gennaio 2004): 7–17. http://dx.doi.org/10.1002/eji.200324693.
3
Bhanja, S. K., M. Sudhagar, A. Goel, N. Pandey, M. Mehra, S. K. Agarwal e A. Mandal. "Differential expression of growth and immunity related genes influenced by in ovo supplementation of amino acids in broiler chickens". Czech Journal of Animal Science 59, No. 9 (1 ottobre 2014): 399–408. http://dx.doi.org/10.17221/7651-cjas.
Abstract (sommario):
The present study was aimed at investigating the role of in ovo administered amino acids: lysine, arginine, threonine or methionine plus cysteine (Met+Cys) in 14-day embryos on expression profile of growth (chicken growth hormone (cGH), insulin like growth factors (IGF) I and II, and mucin) and immunity related genes (IL-2, IL-4, IL-6, IL-12, TNF-α, and IFN-γ). On incubation day (ID) 18, higher (P < 0.01) cGH and mucin gene expression was observed in lysine, threonine, arginine or Met+Cys injected embryos, while IGF-II expression was higher in threonine, arginine or Met+Cys injected embryos on ID 20. Expression of growth genes was down regulated (P < 0.01) on day of hatch in most of the amino acids injected chicks. On day 7 post-hatch (PH), threonine or arginine exhibited higher expression of cGH, IGF-I, and IGF-II but higher mucin gene expression only on day 14 PH. Threonine or Met+Cys injected birds had higher expression of IL-6 and TNF-α, while arginine injected birds had higher TNF-α expression. Lysine, threonine or Met+Cys injected birds had higher IL-2, but lower of IL-12 and IFN-γ gene expression. It is concluded that arginine and threonine enhanced the expression of growth related genes, while threonine and Met+Cys modulated expression of immune genes in broiler chickens.
4
Musilova, P., S. Kubickova, L. Vychodilova-Krenkova, P. Kralik, J. Matiasovic, D. Hubertova, J. Rubes e P. Horin. "Cytogenetic mapping of immunity-related genes in the domestic horse". Animal Genetics 36, n. 6 (25 luglio 2005): 507–10. http://dx.doi.org/10.1111/j.1365-2052.2005.01348.x.
5
Suárez-Calvet, X., E. Gallardo, G. Nogales-Gadea, M. Navas, L. Querol, J. Diaz-Manera, R. Rojas-Garcia e I. Illa. "P.14.1 Dysregulation of innate immunity-related genes in Dermatomyositis". Neuromuscular Disorders 23, n. 9-10 (ottobre 2013): 813. http://dx.doi.org/10.1016/j.nmd.2013.06.609.
6
Kukkonen, Mari K., Tapio Vehmas, Päivi Piirilä e Ari Hirvonen. "Genes involved in innate immunity associated with asbestos-related fibrotic changes". Occupational and Environmental Medicine 71, n. 1 (4 ottobre 2013): 48–54. http://dx.doi.org/10.1136/oemed-2013-101555.
7
Longhi, Maria Serena, Marta Vuerich, Na Wang, Ahmadreza Kalbasi, Alan C. Moss, Adam S. Cheifetz e Simon C. Robson. "Unconjugated bilirubin modulates Th17-cell immunity by curbing glycolysis-related genes". Journal of Immunology 206, n. 1_Supplement (1 maggio 2021): 109.02. http://dx.doi.org/10.4049/jimmunol.206.supp.109.02.
Abstract (sommario):
Abstract Unconjugated bilirubin (UCB) controls Th17-cell function by upregulating the ectonucleotidase CD39 and through activation of aryl-hydrocarbon-receptor (AhR), a modulator of adaptive immunity. UCB-induced CD39 upregulation is defective in Th17-cells of Crohn’s disease (CD) patients. Increasing evidence suggests a role for AhR in regulating glucose metabolism. In this study we tested whether UCB modulates Th17-cell metabolism and whether impaired Th17-cell response to UCB results in metabolic alterations in CD. Th17-cells were differentiated from circulating CD4-cells of 31 healthy controls (HC) and 22 CD patients. Using a multiplex gene expression panel including genes of 8 metabolic pathways, we found that UCB markedly downregulated glycolysis-related genes, particularly phosphoglycerate-kinase-1 (PGK1) and aldolase-A (ALDOA); this effect being prominent in Th17-cells derived from HC but not from CD patients. Reduced Pgk1 and AldoA was also noted in mesenteric-lymph-nodes of mice exposed to dextran-sulfate-sodium-induced colitis and treated with UCB. Functionally, UCB decreased the extracellular-acidification-rate and oxygen-consumption-rate of HC Th17-cells, while this effect was not noted in Th17-cells of CD patients. In vitro silencing of PGK1 and ALDOA further enhanced UCB immunoregulatory properties in HC Th17-cells, by boosting CD39 and Tim-3 while containing IL-17. In conclusion, UCB modulates Th17-cell immunity by downregulating glycolysis-related genes; this property being defective in cells obtained from CD patients. Strategies aimed at blocking/inhibiting glycolytic genes might represent a potential therapeutic tool to restore immune homeostasis in CD and other inflammatory conditions.
8
Cai, Weiwei, Sheng Yang, Ruijie Wu, Yutong Zheng, Shicong He, Lei Shen, Deyi Guan e Shuilin He. "CaSWC4 regulates the immunity-thermotolerance tradeoff by recruiting CabZIP63/CaWRKY40 to target genes and activating chromatin in pepper". PLOS Genetics 18, n. 2 (28 febbraio 2022): e1010023. http://dx.doi.org/10.1371/journal.pgen.1010023.
Abstract (sommario):
Pepper (Capsicum annuum) responds differently to high temperature stress (HTS) and Ralstonia solanacearum infection (RSI) but employs some shared transcription factors (TFs), such as CabZIP63 and CaWRKY40, in both cases. How the plant activates and balances these distinct responses, however, was unclear. Here, we show that the protein CaSWC4 interacts with CaRUVBL2 and CaTAF14b and they all act positively in pepper response to RSI and thermotolerance. CaSWC4 activates chromatin of immunity or thermotolerance related target genes of CaWRKY40 or CabZIP63 by promoting deposition of H2A.Z, H3K9ac and H4K5ac, simultaneously recruits CabZIP63 and CaWRKY40 through physical interaction and brings them to their targets (immunity- or thermotolerance-related genes) via binding AT-rich DNA element. The above process relies on the recruitment of CaRUVBL2 and TAF14 by CaSWC4 via physical interaction, which occurs at loci of immunity related target genes only when the plants are challenged with RSI, and at loci of thermotolerance related target genes only upon HTS. Collectively, our data suggest that CaSWC4 regulates rapid, accurate responses to both RSI and HTS by modulating chromatin of specific target genes opening and recruiting the TFs, CaRUVBL2 and CaTAF14b to the specific target genes, thereby helping achieve the balance between immunity and thermotolerance.
9
Baghoum, Hend, Hend Alahmed, Mahmood Hachim, Abiola Senok, Nour Jalaleddine e Saba Al Heialy. "Simulated Microgravity Influences Immunity-Related Biomarkers in Lung Cancer". International Journal of Molecular Sciences 24, n. 1 (21 dicembre 2022): 155. http://dx.doi.org/10.3390/ijms24010155.
Abstract (sommario):
Microgravity is a novel strategy that may serve as a complementary tool to develop future cancer therapies. In lung cancer, the influence of microgravity on cellular processes and the migratory capacity of cells is well addressed. However, its effect on the mechanisms that drive lung cancer progression remains in their infancy. In this study, 13 differentially expressed genes were shown to be associated with the prognosis of lung cancer under simulated microgravity (SMG). Using gene set enrichment analysis, these genes are enriched in humoral immunity pathways. In lieu, alveolar basal-epithelial (A549) cells were exposed to SMG via a 2D clinostat system in vitro. In addition to morphology change and decrease in proliferation rate, SMG reverted the epithelial-to-mesenchymal transition (EMT) phenotype of A549, a key mechanism in cancer progression. This was evidenced by increased epithelial E-cadherin expression and decreased mesenchymal N-cadherin expression, hence exhibiting a less metastatic state. Interestingly, we observed increased expression of FCGBP, BPIFB, F5, CST1, and CFB and their correlation to EMT under SMG, rendering them potential tumor suppressor biomarkers. Together, these findings reveal new opportunities to establish novel therapeutic strategies for lung cancer treatment.
10
Rowe, Melissah, Emma Whittington, Kirill Borziak, Mark Ravinet, Fabrice Eroukhmanoff, Glenn-Peter Sætre e Steve Dorus. "Molecular Diversification of the Seminal Fluid Proteome in a Recently Diverged Passerine Species Pair". Molecular Biology and Evolution 37, n. 2 (30 ottobre 2019): 488–506. http://dx.doi.org/10.1093/molbev/msz235.
Abstract (sommario):
Abstract Seminal fluid proteins (SFPs) mediate an array of postmating reproductive processes that influence fertilization and fertility. As such, it is widely held that SFPs may contribute to postmating, prezygotic reproductive barriers between closely related taxa. We investigated seminal fluid (SF) diversification in a recently diverged passerine species pair (Passer domesticus and Passer hispaniolensis) using a combination of proteomic and comparative evolutionary genomic approaches. First, we characterized and compared the SF proteome of the two species, revealing consistencies with known aspects of SFP biology and function in other taxa, including the presence and diversification of proteins involved in immunity and sperm maturation. Second, using whole-genome resequencing data, we assessed patterns of genomic differentiation between house and Spanish sparrows. These analyses detected divergent selection on immunity-related SF genes and positive selective sweeps in regions containing a number of SF genes that also exhibited protein abundance diversification between species. Finally, we analyzed the molecular evolution of SFPs across 11 passerine species and found a significantly higher rate of positive selection in SFPs compared with the rest of the genome, as well as significant enrichments for functional pathways related to immunity in the set of positively selected SF genes. Our results suggest that selection on immunity pathways is an important determinant of passerine SF composition and evolution. Assessing the role of immunity genes in speciation in other recently diverged taxa should be prioritized given the potential role for immunity-related proteins in reproductive incompatibilities in Passer sparrows.
Tesi sul tema "Immunity-Related genes":
1
Ahmed, Ashraf. "Investigation of immunity related genes in a disease host using applied bioinformatics". Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18247/.
2
Sedimbi, Saikiran K. "A study on the role of genes of innate immunity in type 1 diabetes". Stockholm, 2010. http://diss.kib.ki.se/2010/978-91-7409-790-0/.
3
Lourenço, Anete Pedro. "Genes codificadores dos peptídeos antimicrobianos e de outras proteínas envolvidas na resposta imune de in Apis mellifera". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-04042008-144240/.
Abstract (sommario):
Os insetos desenvolveram um sistema imune eficiente contra parasitas e patógenos, que compreende a resposta celular e a humoral. Os mecanismos celulares envolvem a fagocitose e a encapsulação pelos hemócitos, enquanto que as respostas humorais incluem a ativação da Profenoloxidase, e a síntese pelo corpo gorduroso dos peptídeos antimicrobianos, que são liberados na hemolinfa. Duas vias de sinalização intracelular, Toll e Imd, controlam a expressão dos genes codificadores dos peptídeos antimicrobianos. A análise do Genoma da abelha Apis mellifera permitiu a identificação dos genes dessas vias. No entanto, pouco se conhece do mecanismo de resposta imune nessas abelhas. Desta maneira, nos propusemos analisar a transcrição de genes efetores da resposta imune (abaecina, hymenoptaecina, defensina, transferrina, profenoloxidase), assim como os genes integrantes das vias de sinalização, tais como os genes de reconhecimento de microorganismos (PGRP, GNBP) e ainda, os de sinalização (cactus, relish, dorsal 1-B). Avaliamos também possíveis proteínas implicadas na resposta imune, como as proteínas de estocagem Vitelogenina, Hexamerina 70a, Lipoforina I/II e Lipoforina III. Finalmente, analisamos o efeito da nutrição e do envelhecimento sobre a imunidade em abelhas. Para análise da expressão dos genes das vias de sinalização, as abelhas foram infectadas com bactérias Serratia marcescens ou Micrococcus luteus por injeção ou via alimentação. A infecção com esses microorganismos provocou a transcrição de peptídeos antimicrobianos e de transferrina em altas quantidades após 3 e 12 horas de tratamento, além da alteração na quantidade de transcritos de outros genes. O papel dos genes profenoloxidase e dorsal na imunidade, descritos como codificadores de importantes proteínas em outros insetos, foi avaliado através da metodologia de silenciamento gênico por RNA de interferência. Observamos a diminuição da transcrição do gene alvo, mostrando a eficiência da metodologia. No entanto, a simples injeção de um RNA de fita dupla foi capaz de ativar o sistema imune de abelhas. Este efeito contribuiu para a dificuldade de atribuição do papel da Profenoloxidase na imunidade de abelhas. Contudo, os resultados de silenciamento de dorsal e suas isoformas, nos levaram a considerar que dorsal 1-A ou dorsal 2 participam da via de sinalização intracelular para produção de peptídeos antimicrobianos, principalmente de defensina. Em relação às proteínas de estocagem, tanto a quantidade de transcritos quanto de proteínas diminui após infecção com bactérias, indicando que estas proteínas estão envolvidas de alguma forma no processo de imunidade em abelhas. Além disso, consumo de alimentos ricos em proteína aumentou os níveis de transcritos das proteínas de estocagem, o que muito provavelmente favorece a manutenção da capacidade de resposta imune de abelhas. O efeito do envelhecimento no declínio da imunidade foi analisado em abelhas nutridoras (novas) e forrageiras (velhas) de uma colônia típica. Além disso, foram utilizadas abelhas de uma colônia single-cohort, que eram de uma mesma idade, mas algumas eram nutridoras, enquanto outras eram forrageiras. Todas as abelhas, independentemente da idade ou comportamento, foram capazes de ativar o sistema imune após infecção pela bactéria S. marcescens. No entanto, as abelhas com o comportamento de forrageira, independentemente da idade, sempre foram mais susceptíveis a infecções que as nutridoras. Este fato se deve, muito provavelmente, às diferenças fisiológicas entre essas abelhas, que proporciona às nutridoras maior competência à sobrevivência.Insects have developed an efficient immune system against parasites and pathogens, which is comprised of both cellular and humoral responses. The cellular mechanisms involve phagocytosis and encapsulation by hemocytes, whereas the humoral responses include activation of prophenoloxidase and synthesis of antimicrobial peptides by the fat body, which are released into the hemolymph. Two signaling pathways, Toll and Imd, control the expression of genes encoding antimicrobial peptides. Genome-wide analyses of the honey bee, Apis mellifera, have identified predicted genes for these signaling pathways. However, immune response mechanisms in honey bees were not yet in depth studied. We analyzed the transcription of effector genes (abaecin, hymenoptaecin, defensin, transferin, prophenoloxidase), as well as other immune genes, such as pathogen recognition genes (PGRP, GNBP) and signaling genes (cactus, relish, dorsal 1- B). We also investigated the role of the storage proteins Vitellogenin, Hexamerin 70a, Lipophorin I/II and Lipophorin III in the honey bee immunity. Finally, we analyzed the effect of nutrition and aging on honey bee immunity. Gene expression of signaling pathway components was assessed in honey bees that had been infected with the bacteria Serratia marcescens or Micrococcus luteus through injection or oral challenge. Honey bees infected with these microorganisms had strong up-regulation of antimicrobial peptide genes and of transferin, and also other changes in transcript abundance after 3 and 12 hours of challenge. The roles of prophenoloxidase and dorsal in the immune response, described as genes encoding important proteins in other insects, were also investigated. In this case we used RNA interference (RNAi) to silence the expression of these genes. RNAi efficiently silenced the target genes. However, injection of doublestranded RNA in honey bees induced a reaction by the immune system. This made it difficult to determine the role of prophenoloxidase in honey bee immunity. Yet, silencing of dorsal and its isoforms led us to consider dorsal 1-A or dorsal 2 as members of the signaling pathways that produce antimicrobial peptides, especially defensin. The abundance of storage proteins transcripts and proteins was lower in infected bees than in controls, giving evidence that these proteins participate in the immune process in honey bees. Moreover, protein consumption caused up-regulation of genes encoding storage proteins, which may favor the maintenace of the immune response capacity. The effect of aging on decline in immunity was analyzed in (young) nurse bees and (old) foragers from normal free-flying colony. We also examined bees from a single-cohort colony, in which all individuals were at the same age; but some were nursing, while others were foraging. All the bees, independent of age or behavior, were able to activate the immune system after infection with S. marcescens. However, foragers, independent of age, were always more susceptible to infections than were nurse bees. This is probably due to physiological differences between bees, which confers to the nurses more competence to survivorship.
4
Sukkar, Dani. "Role of Nosema cerenae and pesticides on the decline of bees : Studies using a multifactorial approach : “Tipping the scale of honeybee immune responses - The effect of pesticides on immune-stimulation mimicking Nosema spp.”". Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0086.
Abstract (sommario):
Les abeilles sont confrontées à la menace mondiale du syndrome d'effondrement des colonies (CCD), entraînant des décès de colonies et une diminution de leur nombre, affectant leur contribution environnementale et agronomique dans la pollinisation des plantes et des cultures commerciales, en plus de la production de miel. L'exposition aux pesticides peut être l'une des principales causes conduisant au CCD en affaiblissant le système immunitaire des abeilles et en altérant leurs réponses immunitaires. Les maladies de la nosémose causées par Nosema spp. peuvent avoir une contribution significative au CCD lorsque les abeilles sont exposées à différents pesticides simultanément. Dans cette étude, plusieurs facteurs de risque sont évalués, y compris les néonicotinoïdes les plus utilisés dans le monde, l'imidaclopride et l'amitraz qui est le pesticide utilisé directement en contact avec les abeilles pour traiter l'infection par les acariens. L'effet de ces pesticides est évalué au niveau de la stimulation immunitaire par zymosan A pour imiter l'infection par Nosema. L'effet des pesticides sur les produits cellulaires antimicrobiens, les réponses cellulaires et l'expression de gènes connexes est démontréHoneybee are facing the global threat of colony collapse disorder (CCD) leading colony deaths and decline in their numbers affecting their environmental and agronomic contribution in pollination of plants and commercial crops in addition to honey production. Pesticide exposure may be of the main causes leading to CCD by weakening the immune system of honeybees and impairing their immune responses. Nosemosis diseases caused by Nosema spp. may have a significant contribution to CCD when bees are exposed to different pesticides simultaneously. Multiple risk factors are assessed in this study including the most used neonicotinoids worldwide, imidacloprid and amitraz which is the pesticide used directly in contact with honeybees to treat mite infection. Th effect of these pesticides is evaluated at the level of immune stimulation by zymosan A to mimic Nosema infection. The effect of pesticides on antimicrobial cells products, cellular responses and related genes' expression are demonstrated
5
Hsieh, Po-chien, e 謝伯謙. "Association between Genetic Polymorphisms in Inflammation-related and Innate Immunity-related Genes and the Risk of Breast Cancer". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/61055238959539543594.
Abstract (sommario):
碩士國防醫學院
公共衛生學研究所
100
A hospital-based case-control study was conducted to investigate the association between genetic polymorphisms in inflammation-related (COX2, CRP) and innate immunity-related (FCER1A) genes and the risk of breast cancer. The cases involved 342 women with confirmed histopathologic diagnosis of breast carcinoma, and the controls were 684 matched females attending the health examination clinics of the same hospital. Each subject was undergone a questionnaire interview about sociodemographic characteristics and risk factors of breast cancer, was measured for anthropometric status and was drawn a 10-ml blood sample for genotyping by the OpenArray system. A total of 10 single nucleotide polymorphisms (SNPs) were selected according to functional data and the minor allele frequencies (MAF) > 5%. Logistic regression models with the calculation of odds ratio (OR) and 95% confidence interval (CI) were performed to estimate the risks for breast cancer associated with harboring individual specific genotypes and haplotypes. Furthermore, the interactions between haplotypes in studied genes and the duration of estrogen exposure on the risk of breast cancer were also assessed. Study results indicated that SNP of rs2494250 in FCER1A gene increased the risk of breast cancer (OR = 1.39, 95% CI: 1.05-1.85). In haplotype analysis, odds ratios of breast cancer for those who carried the GGA haplotype in FCER1A gene and with waist circumference lower than 80 cm and with longer duration of estrogen exposure (≥ 35 years) were 2.25 (95% CI: 1.01-5.01) and 2.76 (95% CI: 1.13-6.76), respectively. No interactions were found between haplotypes in studied genes and the duration of estrogen exposure on the risk of breast cancer. This study suggested that SNP of FCER1A gene would increase the risk of breast cancer, and a higher risk was found for those with the GGA haplotype and longer duration of estrogen exposure.
6
Torti, Dax. "Functional Roles of the SWI/SNF ATPase Brahma Related Gene 1 (BRG1) and Special AT-Rich Binding Protein (SATB1) in Virus Response and Innate Immunity". Thesis, 2012. http://hdl.handle.net/1807/32831.
Abstract (sommario):
The innate immune response is a primary transcriptional defence network activated by interferons (IFNs) α/ β in response to viral infection. A cell must have the capability to detect the virus, activate signalling cascades, and engage transcriptional anti-viral networks. IFNs trigger the Signal Transducer and Activator of Transcription (STAT) family, which in turn induce anti-viral gene expression. Recruitment of STATs to IFN stimulated gene (ISG) promoters and the ensuing gene induction requires Brahma Related Gene 1 (BRG1), the catalytic component of the SWI/ SNF chromatin remodelling (or BAF) complex.
Cell lines with high BRG1 expression are hyper-responsive to IFN induced transcription, conversely BRG1 low cells exhibit impaired induction. However, BRG1 high cells that are resistant to Encephalomyocarditis virus infection did not require signalling through the IFN receptor complex for anti-viral immunity. This suggested 2F-BRG1 cells must rely on BRG1 dependent non-ISGs or an as yet uncharacterized subset of basally expressed BRG1-dependent ISGs that do not require IFN enhanced expression for anti-viral activity. Utilizing genome wide microarrays we identified five genes with potent anti-viral activity. These genes may restrict viral infection through alterations in integrin signalling, endosomal trafficking, and activation of host transcriptional responses.
We also investigated the role of Special AT-Rich Binding Protein (SATB1) in regulation of IFN responsive genes. The loss of this chromatin binding protein is associated with transcriptional changes in the MHC locus that mimic IFNγ induced expression. Through microarray analysis we discovered a remarkable 47% of IFNα regulated genes were co-regulated by SATB1; 42% of IFNα induced genes were induced by SATB1 knock down, while 63% of IFNα repressed genes were SATB1 dependent. Functionally, knock down of SATB1 protected cells from EMCV induced cell death at low multiplicity of infection (MOI), and increased the cytoprotective effect of IFNα against EMCV at higher MOIs.
Analysis of IFNα, SATB1 and BRG1 regulated genes revealed a subset of core genes regulated by all three factors that may be critical to robust anti-viral immunity. The potent immunosuppressive properties of SATB1 suggest this protein may be involved in complex immunopathologies. The immuno-modulatory properties of SATB1 and BRG1 established in this thesis provide substantive evidence for the development of pharmaceutical therapies targeting these proteins.
Capitoli di libri sul tema "Immunity-Related genes":
1
Lee, Chi-Jen, e Zhong-Ming Li. "Protective Immunity and Gene Expression Related to Pneumococcal Glycoconjugate". In The Molecular Immunology of Complex Carbohydrates —2, 505–14. Boston, MA: Springer US, 2001. http://dx.doi.org/10.1007/978-1-4615-1267-7_33.
2
Bringer, Marie-Agnès, Pierre Lapaquette, Hang Nguyen e Arlette Darfeuille-Michaud. "Polymorphisms in Autophagy-Related Genes in Crohn’s Disease". In Autophagy: Cancer, Other Pathologies, Inflammation, Immunity, Infection, and Aging, 93–110. Elsevier, 2014. http://dx.doi.org/10.1016/b978-0-12-405529-2.00006-8.
3
Martin, Maureen P., M. Tevfik Dorak e Mary Carrington. "Killer Immunoglobulin-Like Receptor and Related Genes". In Genetic Susceptibility to Infectious Diseases, 89–106. Oxford University PressNew York, NY, 2008. http://dx.doi.org/10.1093/oso/9780195174908.003.0007.
Abstract (sommario):
Abstract Natural killer (NK) cells are an important component of the innate immune system; they participate in early responses against infected or transformed cells by production of cytokines and direct cytotoxicity (Bancroft 1993; Biron et al. 1999; Cooper et al. 2001; French and Yokoyama 2003; Robertson and Ritz 1990; Trinchieri 1989). The importance of NK cells in antiviral immunity is evidenced by the report of an NK-cell– deficient individual with otherwise normal B and T cells who suffered from recurrent herpesvirus infections (Biron et al. 1989). Other studies have also implicated NK cells in the pathogenesis of viral infections, including cytomegalovirus (CMV), Epstein-Barr virus, herpes simplex virus (HSV), hepatitis B, hepatitis C (HCV), and HIV-1, as well as a variety of intracellular bacteria and protozoan parasites (reviewed in Bancroft 1993; Biron et al. 1999; See et al. 1997). Thus, it is clear that NK cells, key components of the innate immune system, are essential in limiting pathogens during the early phases of a primary infection before the adaptive immune system is able to respond.
4
Wills, Bridget, e Yee-Sin Leo. "Dengue". In Oxford Textbook of Medicine, a cura di Christopher P. Conlon, 845–52. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0090.
Abstract (sommario):
Dengue is the most important mosquito-borne viral infection to affect humans. It is an RNA virus in the Flavivirus genus, family Flaviviridae. There are four closely related but serologically distinct viral serotypes, all of which may cause disease. Following infection with one serotype there is lifelong immunity to that serotype but the possibility of more severe disease during a subsequent infection with a different serotype. The primary mosquito vector is Aedes aegypti. Recent estimates suggest around 100 million symptomatic, and many more asymptomatic, infections occur annually worldwide. The disease is hyperendemic in many large Asian cities, and is also a significant problem in the Pacific region and in the Americas.
5
Ravi, Sangeetha, Parimalanandhini Duraisamy, Mahalakshmi Krishnan, Livya Catherene Martin, Raman Thiagarajan, Angusamy Annapoorani, Munuswamy Arumugam, Sundaram Janarthanan e Ramar Manikandan. "Immunological Significance of Steroids and Implications for Immune Related Diseases". In Steroids and their Medicinal Potential, 175–94. BENTHAM SCIENCE PUBLISHERS, 2023. http://dx.doi.org/10.2174/789815049336123010010.
Abstract (sommario):
This book chapter compiles a general idea of steroids and their overall biological significance in immunity and immune-associated diseases. Steroids chemically comprise a group of cyclical organic compounds constituted by seventeen carbon atoms that consist of four fused rings called sterane, and cyclopentanoperhydrophenanthrene. The four-ringed structures are mainly synthesized by mitochondria and smooth endoplasmic reticulum through the cyclization of thirty-carbon chain squalene into lanosterol or cycloartenol. Steroid hormones differ only in number of oxygen and carbon atoms, but all are derived from cholesterol. The biological significance of steroids and their derivatives range from energy metabolism, and body growth to the control of reproductive activities. However, deficiency or malfunctioning of steroids can lead to direct effects on body salt/sugar levels, sexual differentiation and immunity. As far as immune responses are concerned, a lot of research works have emerged which show the importance of steroids in immune regulation, and in extreme cases, they are also known to result in immune-related diseases. Most of these effects are mediated by the influence of steroids on gene expression in cells and this could in turn prove to be novel drug targets as well. We have made an attempt in this chapter to update and highlight the role of steroids in immune regulation and immune-related diseases, which we hope would open up therapeutic options for diseases.
6
Ahmad Bhat, Kaisar, Tasaduq Manzoor, Mashooq Ahmad Dar, Asmat Farooq, Kaisar Ahmad Allie, Shaheen Majeed Wani, Tashook Ahmad Dar e Ali Asghar Shah. "Salmonella Infection and Pathogenesis". In Enterobacteria. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.102061.
Abstract (sommario):
Salmonella genus represents most common food borne pathogens isolated from food producing animals and is responsible for causing zoonotic infections in humans and other animal species, including birds. As a result, Salmonella diseases are among the most common problems for the humans, animals, and food industry around the world. Despite rising attention about other pathogens, Salmonella continues to be the most prominent cause of food borne disease worldwide. Salmonella can be transferred to humans at any point along the farm-to-fork chain, most commonly through infected animal-derived foods such as poultry and poultry related products (eggs), pork, fish, and so on. Some Salmonella serotypes have been confined to a single serovar and are known as “host-restricted” while the others have a wide host spectral range and are known as “host-adapted” serotypes. Globally Salmonella infection causes huge mortality and the infection plays a huge role in immune response by evolving multiple mechanism to subvert immunity to its own benefit. Numerous infectivity markers and determinants have indeed been reported to play essential role in Salmonella pathogenesis to colonize its host by invading and avoiding the host’s intestinal shielding system.
7
Gahramanova, Sona. "Mechanism of Development of Arterial Hypertension Associated with the Exchange of Level Vitamin D". In Hypertension [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.102774.
Abstract (sommario):
Arterial hypertension (AH) is one of the most chronic and fatal disorders in the world, the main risk factors for which are age, hereditary predisposition, race, tobacco use, high salt intake, etc., as well as low vitamin D. In the last 10 years, there has been an increasing interest in the extraosseous effects of vitamin D. Being a hormone-like vitamin, it participates in many vital processes of the body. Its level is closely related to various metabolic disorders, diseases of the cardiovascular system (CVS), arterial hypertension (AH), diabetes mellitus, the immune system, cancer, etc. Vitamin D improves vascular endothelial function, due to which it has a vasoprotective effect, improves blood pressure, reduces vascular and myocardial remodeling, reduces the risk of left ventricular hypertrophy, slows down fibrosis, reduces the risk of atherosclerosis, reduces insulin resistance and inflammation, and improves immunity. It has been proven that vitamin D has an inverse relationship with renin, it reduces the expression of the renin gene. At a normal level of vitamin D, the concentration of renin and aldosterone II decreases, which has a positive effect on the course of hypertension.
8
Tariq, Aqsa, e Ambreen Ahmed. "Bacterial Symbiotic Signaling in Modulating Plant-Rhizobacterial Interactions". In Symbiosis in Nature [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.109915.
Abstract (sommario):
Rhizosphere is the hub for microbial activities where microbes and plants interact with complex signaling mechanisms. Plants release various metabolites in response to environmental factors which are significant in shaping rhizospheric microbial communities. These microbes develop symbiotic relation with plants by quorum sensing signals and regulate various microbial activities including biofilm formation. Biofilms are important in inhabiting rhizosphere and provide platform for cell-to-cell microbial interactions. Biofilm- forming rhizobacteria can successfully colonize plant roots and establish symbiotic relations with host. During this association, rhizobacteria are flourished by using plant root exudates, while the bacteria benefit the plants by synthesizing phytohormones, locking soil minerals for plant, protecting them from pathogenic invasions and enhancing plant immunity by improving plant tolerance against various environmental conditions. Indole is an effector molecule in regulating bacterial gene expression related to biofilm production. These interactions are coordinated by bacterially released phytohormones mainly auxin which act as key factor in regulating plant-microbe symbiotic interactions. It is characterized as inter- kingdom signaling molecule that coordinates various plant and rhizobacterial activities. Thus, understanding the nature and interacting behaviors of these molecules would lead to the exploitation of plant growth-promoting rhizobacteria for better plant growth in agricultural fields.
Atti di convegni sul tema "Immunity-Related genes":
1
Božić, Dragica, Katarina Živančević, Katarina ,. Baralić, Dragana Javorac, Aleksandra Buha Đorđević, Evica Antonijević Miljaković, Đurđica Marić et al. "APPLYING „IN SILICO“ TOXICOGENOMIC DATA MINING TO PREDICT MOLECULAR MECHANISMS AND PATHWAYS AGAINST CARCINOMA: IMMUNOMODULATOR SULFORAPHANE AS A CASE STUDY". In 1st INTERNATIONAL Conference on Chemo and BioInformatics. Institute for Information Technologies, University of Kragujevac,, 2021. http://dx.doi.org/10.46793/iccbi21.470b.
Abstract (sommario):
The aim of this study was to predict the molecular mechanisms and pathways of immunomodulator sulforaphane (SFN) against carcinoma using in silico toxicogenomic data mining. Three key tools applied in our analysis were Comparative Toxicogenomics Database (CTD; http://CTD.mdibl. org), ToppGene Suite portal (https://toppgene.cchmc.org) and Reactome Knowledgebase (https://reactome.org). Sulforaphane interacted with a total of 1896, among which NFE2L2, NQO1, HMOX1, GCLC, TXNRD1, IL1B, IFNG, AGT, KEAP1, and CASP3 had the highest number of interactions. In the CTD, there were direct evidences that SFN interacts with a total of 169 genes to express a therapeutic effect against different types of cancer such as: hepatocellular carcinoma (113), colorectal neoplasms (67), uterine cervical neoplasms (10), and adenomatous polyposis coli (4). This set of genes was further uploaded into the Gene Mania software, ToppGene Suite portal, and Reactome Knowledgebase, which confirmed that molecular functions, biological processes and pathways of SFN-affected genes were mostly related to oxidoreductase activity, regulation of immune system, and apoptosis. In conclusion, we may suggest that SFN interacts with host immunity to enhance the eradication of tumor cells mainly by inducing immune-response and stimulating apoptotic process of tumor cells. Moreover, its antioxidative activity could contribute to better anti-cancerogenic effects.
2
"Disentangling the multiphasic nature of intracellular calcium responses induced by fungal signals in Lotus japonicus roots". In IS-MPMI Congress. IS-MPMI, 2023. http://dx.doi.org/10.1094/ismpmi-2023-10.
Abstract (sommario):
The recognition of different microbe-associated molecular patterns triggers in the plant the activation of either an immune response or an accommodation program. In both types of responses, Ca2+ is a crucial intracellular messenger, mediating the early stages of the respective signalling pathways. In this work, we analyzed the cytosolic and nuclear Ca2+ changes activated by a set of chitin-related oligomers in different genetic backgrounds of Lotus japonicus roots by using specifically targeted aequorin-based Ca2+ reporters. By means of pharmacological and genetic approaches, we dissected the plant Ca2+ responses into two separable and temporally distinct components. A complementary approach carried out via a cameleon-based bioassay in Medicago truncatula root organ cultures further supports the occurrence of different temporal phases in the observed Ca2+ transients. While the second phase of the Ca2+ change represents the well-known Ca2+ spiking phenomenon, we show that the occurrence of the rapid first phase, which critically depends on the elicitor concentration, correlates with the activation of plant immunity marker genes. Our data provide clues to a better understanding of the subtle boundaries between symbiotic and immunity responses in plant-fungus interactions.
3
Smatti, Maria Khalid, Yasser Al-Sarraj, Omar Albagha e Hadi Yassine. "Genetic Susceptibility to Infectious Diseases in the Qatari Population". In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2021. http://dx.doi.org/10.29117/quarfe.2021.0092.
Abstract (sommario):
Background: Infectious diseases (IDs) account for 8% of deaths annually in Qatar, and therefore, represent a significant challenge for public health. Interestingly, the spread and severity of viral infections vary considerably between individuals and populations. The most recent example is SARS-CoV-2, which ranges from mild/asymptomatic to a severe respiratory syndrome. It has been previously reported that polymorphisms in genes linked to immunity can influence individuals’ responses to infections as observed in tuberculosis, influenza, and HIV; however, studies exploring causal host genetic variants in IDs are still limited and dramatically skewed with regard to population inclusion. In fact, the genetic susceptibility to IDs in the Qatari population is largely unknown. Aim: To perform a comprehensive genetic screening to investigate the presence and frequency of variants previously associated with various infections in the Qatari population. Methods: Whole-genome sequencing was previously performed for 18,000 QBB participants using Illumina HiSeq X Ten1 sequencers. The initial data processing and quality assessment of the raw data has also been performed and variant calling files (VCF) were created. We were granted the access to the VCF files of 6,218 sequenced samples. The genetic variant data was then converted to PLINK file format using PLINK-1.9. Standardized quality-assurance and quality control (QA/QC) methods were followed to generate high quality and confidence on both SNPs and sample levels. The final file used for calculating allele frequency contained 6,047 subjects. Additionally, list of infections-related SNPs that were previously reported in the literature and deposited in GWAS catalog was extracted and used to calculate and compare the allelic frequency in the Qatari genomes compared to other populations. Results: The frequency of infections-related SNPs in the Qatari population was significantly lower for most infections. Most variants (78%) showed negative fold change in the Qatari genomes. Only 22% of all variants were more prevalent in Qatari population compared to others. The most significant differences were observed in genes related to TB and HIV (200-940 and 160-710 fold change, respectively). Conclusion: This study reports a lower susceptibility of the Qatari population to IDs in general. Nonetheless, this might also indicate the presence of unknown Qatari-unique variants and hence, highlights the need for further investigation in future GWAS.
4
Muntyan, Victoria S., Alla S. Saksaganskaia, Alexey N. Muntyan, Mariia E. Vladimirova e Marina L. Roumiantseva. "STRESS AND IMMUNITY OF NODULE BACTERIA SINORHIZOBIUM MELILOTI: LOCALIZATION, POLYMORPHISM AND PHYLOGENY OF GENETIC DETERMINANTS". In 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022/6.1/s25.15.
Abstract (sommario):
Sinorhizobium meliloti are agriculturally valuable species of soil bacteria that form nitrogen-fixing symbiosis with alfalfa plants. Global climate changes lead to an increase of agricultural areas subjected to salinity. Current knowledge about about high-salt stress impact on soil saprophitic root nodulated microsymbionts of legumes is weakly studied and rhizobia gene pool responsible for salt tolerance are fragment and far from clear. An increase of bacteria nonspecific resistance (immune status) to unfavorable stress factors can occur through the induction of defense mechanisms like restrictionmodification systems and CRISPR/cas systems which are aimed to protect bacteria cells from bacteriophages widespread in soil microbiome. The aim of this research was to evaluate the role of the megaplasmid pSymA in the formation of ecological genome of S. meliloti, which is related to stress tolerance and to determine the location of elements of adaptive immune systems protecting root nodule bacteria against external foreign DNA. The analysis was done on 11 genes, products of which involved in response to ion stress and synthesis of osmoprotectors. It was found that 6 out of 11 genes were found in the genomes of all analyzed S. meliloti strains, while it was not a case for other 5 genes. It was found that, unlike chromosome, megaplasmid I of S. meliloti accumulated copies of 4 from 5 genes, except kdpA gene, which is represented by a single copy and localized on megaplasmid I in all so far studied strains. It was predicted that closest phylogenetic relatives of genes whose products are involved in response to ion stress as well in synthesis of osmoprotectors are homologous genes of closely related S. medicae species. The exception was for betI2, for which the closest phylogenetic relative was homologous gene of Klebsiella pneumonia, and another exception is kdpA gene introduced onto megaplasmid-I from actinobacteria. Regarding elements of immune systems it was revealed that nonsymbiotic plasmids of S. meliloti harbored incomplete elements of RMS-I, -II, and - III systems, while the 4 complete RMS-IV systems were detected on a single plasmid. It was found out that corresponding methylases had similarities with similar enzymes detected in nitrogen-fixing strains of Agrobacterium tumefaciens, Mezorhizobium sp., Bradyrhizobium sp. CRISPR sequences were not detected on megaplasmid-I, while they were on chromosome, megaplasmid-II and on cryptic plasmids. So, it was concluded that megaplasmid-I of S. meliloti are enriched in copies of genes related to osmotic stress tolerance, but it role in immune status of rhizobia is requested further elucidation.
5
"Expression of IPD3, a transcriptional regulator of AM symbiosis, affects immunity and flowering time in non-host Arabidopsis". In IS-MPMI Congress. IS-MPMI, 2023. http://dx.doi.org/10.1094/ismpmi-2023-13.
Abstract (sommario):
Arbuscular mycorrhizal symbiosis (AM) is a beneficial trait originating with the first land plants. The ability to host AM has since been lost from diverse plant species. Genes in the Common Symbiosis Pathway that are essential to establish AM hosting were lost from Brassicaceae along with the trait itself, including Interacting Protein of DMI3 (IPD3), a key transcription factor connecting upstream signaling of AM fungal presence to the downstream gene-regulatory network for AM functions. We generated transgenic Arabidopsis plants expressing the DNA-binding domain of IPD3 and used phenotypic and transcriptome analysis to characterize the effect of IPD3 expression in Arabidopsis in the presence and absence of AM fungus Rhizophagus irregularis. We compared these results to the AM-host model Lotus japonicus and its ipd3 knockout mutant cyclops-4. Despite its long history as a non-AM species, restoring IPD3 expression to Arabidopsis significantly altered transcription related to growth and defense, and delayed flowering time. Our comparative transcriptomic results indicate that some genetic connections for IPD3 remain conserved in Arabidopsis despite the long evolutionary time since its loss.
Rapporti di organizzazioni sul tema "Immunity-Related genes":
1
Barefoot, Susan, Benjamin Juven, Thomas Hughes, Avraham Lalazar, A. B. Bodine, Yitzhak Ittah e Bonita Glatz. Characterization of Bacteriocins Produced by Food Bioprocessing Propionobacteria. United States Department of Agriculture, agosto 1992. http://dx.doi.org/10.32747/1992.7561061.bard.
Abstract (sommario):
Objectives were to further characterize activity spectra of dairy propionibacteria bacteriocins, jenseniin G and propionicin PLG-1, purify them, examine the role of cell walls in resistance, examine their interactions with cytoplasmic membrane, explain producer immunity, and clone the responsible genes. Inhibitory spectra of both bacteriocins were further characterized. Propionicin was most effective in controlling Gram-positive, rather than Gram-negative organisms; it controlled growth of sensitive cells both in a culture medium and a model food system. Jenseniin inhibited yogurt cultures and may help prevent yogurt over-acidification. Both were active against botulinal spores; jenseniin was sporostatic; propionicin was sporicidal. Jenseniin was produced in broth culture, was stable to pH and temperature extremes, and was purified. Its molecular mass (3649 Da) and partial amino acid composition (74%) were determined. A blocked jenseniin N-terminus prevented sequencing. Methods to produce propionicin in liquid culture were improved, and large scale culture protocols to yield high titers were developed. Methods to detect and quantify propionicin activity were optimized and standardized. Stability of partially purified propionicin was demonstrated and an improved purification scheme was developed. Purified propionicin had a 9328-Da molecular mass, contained 99 amino acids, and was significantly hydrophobic; ten N-terminal amino acids were identified. Propionicin and Jenseniin interacted with cytoplasmic membranes; resistance of insensitive species was cell wall-related. Propionicin and jenseniin acted similarly; their mode of action appeared to differ from nisin. Spontaneous jenseniin-resistant mutants were resistant to propionicin but nisin-sensitive. The basis for producer immunity was not resolved. Although bacteriocin genes were not cloned, a jenseniin producer DNA clone bank and three possible vectors for cloning genes in propionibacteria were constructed. In addition, transposon Tn916 was conjugatively transferred to the propionicin producer from chromosomal and plasmid locations at transfer frequencies high enough to permit use of Tn916 for insertional mutagenesis or targeting genes in propionibacteria. The results provide information about the bacteriocins that further supports their usefulness as adjuncts to increase food safety and/or quality.
2
Sessa, Guido, e Gregory Martin. MAP kinase cascades activated by SlMAPKKKε and their involvement in tomato resistance to bacterial pathogens. United States Department of Agriculture, gennaio 2012. http://dx.doi.org/10.32747/2012.7699834.bard.
Abstract (sommario):
The research problem: Pseudomonas syringae pv. tomato (Pst) and Xanthomonas campestrispv. vesicatoria (Xcv) are the causal agents of tomato bacterial speck and spot diseases, respectively. These pathogens colonize the aerial parts of the plant and cause economically important losses to tomato yield worldwide. Control of speck and spot diseases by cultural practices or chemicals is not effective and genetic sources of resistance are very limited. In previous research supported by BARD, by gene expression profiling we identified signaling components involved in resistance to Xcvstrains. Follow up experiments revealed that a tomato gene encoding a MAP kinase kinase kinase (MAPKKKe) is required for resistance to Xcvand Pststrains. Goals: Central goal of this research was to investigate the molecular mechanisms by which MAPKKKεand associated MAP kinase cascades regulate host resistance. Specific objectives were to: 1. Determine whether MAPKKKεplays a broad role in defense signaling in plants; 2. Identify components of MAP kinase cascades acting downstream of MAPKKKε; 3. Determine the role of phosphorylation-related events in the function of MAPKKKε; 4. Isolate proteins directly activated by MAPKKKε-associatedMAPK modules. Our main achievements during this research program are in the following major areas: 1. Characterization of MAPKKKεas a positive regulator of cell death and dissection of downstream MAP kinase cascades (Melech-Bonfil et al., 2010; Melech-Bonfil and Sessa, 2011). The MAPKKKεgene was found to be required for tomato resistance to Xcvand Pstbacterial strains and for hypersensitive response cell death triggered by different R gene/effector gene pairs. In addition, overexpression analysis demonstrated that MAPKKKεis a positive regulator of cell death, whose activity depends on an intact kinase catalytic domain. Epistatic experiments delineated a signaling cascade downstream of MAPKKKεand identified SIPKK as a negative regulator of MAPKKKε-mediated cell death. Finally, genes encoding MAP kinase components downstream of MAPKKKεwere shown to contribute to tomato resistance to Xcv. 2. Identification of tomato proteins that interact with MAPKKKεand play a role in plant immunity (Oh et al., 2011). We identified proteins that interact with MAPKKKε. Among them, the 14-3-3 protein TFT7 was required for cell death mediated by several R proteins. In addition, TFT7 interacted with the MAPKK SlMKK2 and formed homodimersin vivo. Thus, TFT7 is proposed to recruit SlMKK2 and MAPKKK client proteins for efficient signal transfer. 3. Development of a chemical genetic approach to identify substrates of MAPKKKε-activated MAP kinase cascades (Salomon et al., 2009, 2011). This approach is based on engineering the kinase of interest to accept unnatural ATP analogs. For its implementation to identify substrates of MAPKKKε-activated MAP kinase modules, we sensitized the tomato MAP kinase SlMPK3 to ATP analogs and verified its ability to use them as phosphodonors. By using the sensitized SlMPK3 and radiolabeled N6(benzyl)ATP it should be possible to tag direct substrates of this kinase. 4. Development of methods to study immunity triggered by pathogen-associated molecular patterns (PAMPs) in tomato and N. benthamiana plants (Kim et al., 2009; Nguyen et al. 2010). We developed protocols for measuring various PTI-associatedphenotypes, including bacterial populations after pretreatment of leaves with PAMPs, induction of reporter genes, callose deposition at the cell wall, activation of MAP kinases, and a luciferase-based reporter system for use in protoplasts. Scientific and agricultural significance: Our research activities discovered and characterized a signal transduction pathway mediating plant immunity to bacterial pathogens. Increased understanding of molecular mechanisms of immunity will allow them to be manipulated by both molecular breeding and genetic engineering to produce plants with enhanced natural defense against disease. In addition, we successfully developed new biochemical and molecular methods that can be implemented in the study of plant immunity and other aspects of plant biology.
3
Sessa, Guido, e Gregory Martin. Role of GRAS Transcription Factors in Tomato Disease Resistance and Basal Defense. United States Department of Agriculture, 2005. http://dx.doi.org/10.32747/2005.7696520.bard.
Abstract (sommario):
The research problem: Bacterial spot and bacterial speck diseases of tomato are causedby strains of Xanthomonas campestris pv. vesicatoria (Xcv) and Pseudomonas syringae pv.tomato (Pst), respectively. These bacteria colonize aerial parts of the plant and causesignificant losses in tomato production worldwide. Protection against Xcv and Pst bycultural practices or chemical control has been unsuccessful and there are only limitedsources of genetic resistance to these pathogens. In previous research supported in part byBARD IS-3237-01, we extensively characterized changes in tomato gene expression uponthe onset of spot and speck disease resistance. A remarkable finding of these studies wasthe inducibility in tomato leaves by both Xcv and Pst strains of genes encodingtranscriptional activator of the GRAS family, which has not been previously linked todisease resistance. Goals: Central goals of this research were to investigate the role of GRAS genes in tomatoinnate immunity and to assess their potential use for disease control.Specific objectives were to: 1. Identify GRAS genes that are induced in tomato during thedefense response and analyze their role in disease resistance by loss-of-function experiments.2. Overexpress GRAS genes in tomato and characterize plants for possible broad-spectrumresistance. 3. Identify genes whose transcription is regulated by GRAS family. Our main achievements during this research program are in three major areas:1. Identification of tomato GRAS family members induced in defense responses andanalysis of their role in disease resistance. Genes encoding tomato GRAS family memberswere retrieved from databases and analyzed for their inducibility by Pst avirulent bacteria.Real-time RT-PCR analysis revealed that six SlGRAS transcripts are induced during theonset of disease resistance to Pst. Further expression analysis of two selected GRAS genesshowed that they accumulate in tomato plants in response to different avirulent bacteria orto the fungal elicitor EIX. In addition, eight SlGRAS genes, including the Pst-induciblefamily members, were induced by mechanical stress in part in a jasmonic acid-dependentmanner. Remarkably, SlGRAS6 gene was found to be required for tomato resistance to Pstin virus-induced gene silencing (VIGS) experiments.2. Molecular analysis of pathogen-induced GRAS transcriptional activators. In aheterologous yeast system, Pst-inducible GRAS genes were shown to have the ability toactivate transcription in agreement with their putative function of transcription factors. Inaddition, deletion analysis demonstrated that short sequences at the amino-terminus ofSlGRAS2, SlGRAS4 and SlGRAS6 are sufficient for transcriptional activation. Finally,defense-related SlGRAS proteins were found to localize to the cell nucleus. 3. Disease resistance and expression profiles of transgenic plants overexpressing SlGRASgenes. Transgenic plants overexpressing SlGRAS3 or SlGRAS6 were generated. Diseasesusceptibility tests revealed that these plants are not more resistant to Pst than wild-typeplants. Gene expression profiles of the overexpressing plants identified putative direct orindirect target genes regulated by SlGRAS3 and SlGRAS6. Scientific and agricultural significance: Our research activities established a novel linkbetween the GRAS family of transcription factors, plant disease resistance and mechanicalstress response. SlGRAS6 was found to be required for disease resistance to Pstsuggesting that this and possibly other GRAS family members are involved in thetranscriptional reprogramming that takes place during the onset of disease resistance.Their nuclear localization and transcriptional activation ability support their proposed roleas transcription factors or co-activators. However, the potential of utilizing GRAS familymembers for the improvement of plant disease resistance in agriculture has yet to bedemonstrated.
4
Hedrick, Ronald, e Herve Bercovier. Characterization and Control of KHV, A New Herpes Viral Pathogen of Koi and Common Carp. United States Department of Agriculture, gennaio 2004. http://dx.doi.org/10.32747/2004.7695871.bard.
Abstract (sommario):
In this project we proposed to characterize the virus genome and the structural virion polypeptides to allow development of improved diagnostic approaches and potential vaccination strategies. These goals have been mostly achieved and the corresponding data were published in three papers (see below) and three more manuscripts are in preparation. The virion polypeptides of KHV strains isolated from USA (KHV-U) and Israel (KHV-I) were found to be identical. Purified viral DNA analyzed with a total of 5 restriction enzymes demonstrated no fragment length polymorphism between KHV-I and KHV-U but both KHV isolates differed significantly from the cyprinid herpesvirus (CHV) and the ictalurid herpesvirus (channel catfish virus or CCV). Using newly obtained viral DNA sequences two different PCR assays were developed that need to be now further tested in the field. We determined by pulse field analysis that the size of KHV genome is around 280 kbp (1-1. Bercovier, unpublished results). Sequencing of the viral genome of KHV has reached the stage where 180 kbp are sequenced (twice and both strands). Four hypothetical genes were detected when DNA sequences were translated into amino acid sequences. The finding of a gene of real importance, the thymidine kinase (TK) led us to extend the study of this specific gene. Four other genes related to DNA synthesis were found. PCR assays based on defined sequences were developed. The PCR assay based on TK gene sequence has shown improved sensitivity in the detection of KHV DNA compared to regular PCR assays. </P> <P><SPAN>With the ability to induce experimental infections in koi with KHV under controlled laboratory conditions we have studied the progress and distribution of virus in host tissues, the development of immunity and the establishment of latent infections. Also, we have investigated the important role of water temperature on severity of infections and mortality of koi following infections with KHV. These initial studies need to be followed by an increased focus on long-term fate of the virus in survivors. This is essential in light of the current "controlled exposure program" used by farmers to produce KHV "naturally resistant fish" that may result in virus or DNA carriers. </SPAN></P> <P><SPAN>The information gained from the research of this project was designed to allow implementation of control measures to prevent the spread of the virus both by improved diagnostic approaches and preventive measures. We have accomplished most of these goals but further studies are needed to establish even more reliable methods of prevention with increased emphases on improved diagnosis and a better understanding of the ecology of KHV. </SPAN>
5
Chejanovsky, Nor, e Bruce A. Webb. Potentiation of Pest Control by Insect Immunosuppression. United States Department of Agriculture, gennaio 2010. http://dx.doi.org/10.32747/2010.7592113.bard.
Abstract (sommario):
The restricted host range of many baculoviruses, highly pathogenic to Lepidoptera and non-pathogenic to mammals, limits their use to single or few closely related Lepidopteran species and is an obstacle to extending their implementation for pest control. The insect immune response is a major determinant of the ability of an insect pathogen to efficiently multiply and propagate. We have developed an original model system to study the Lepidopteran antiviral immune response based on Spodoptera littoralis resistance to AcMNPV (Autographa californica multiple nucleopolyhedrovirus) infection and the fascinating immunosuppressive activity of polydnaviruses .Our aim is to elucidate the mechanisms through which the immunosuppressive insect polydnaviruses promote replication of pathogenic baculoviruses in lepidopteran hosts that are mildly or non-permissive to virus- replication. In this study we : 1- Assessed the extent to which and the mechanisms whereby the immunosuppressive Campoletis sonorensis polydnavirus (CsV) or its genes enhanced replication of a well-characterized pathogenic baculovirus AcMNPV, in polydnavirus-immunosuppressedH. zea and S. littoralis insects and S. littoralis cells, hosts that are mildly or non-permissive to AcMNPV. 2- Identified CsV genes involved in the above immunosuppression (e.g. inhibiting cellular encapsulation and disrupting humoral immunity). We showed that: 1. S. littoralis larvae mount an immune response against a baculovirus infection. 2. Immunosuppression of an insect pest improves the ability of a viral pathogen, the baculovirus AcMNPV, to infect the pest. 3. For the first time two PDV-specific genes of the vankyrin and cystein rich-motif families involved in immunosuppression of the host, namely Pvank1 and Hv1.1 respectively, enhanced the efficacy of an insect pathogen toward a semipermissive pest. 4. Pvank1 inhibits apoptosis of Spodopteran cells elucidating one functional aspect of PDVvankyrins. 5. That Pvank-1 and Hv1.1 do not show cooperative effect in S. littoralis when co-expressed during AcMNPV infection. Our results pave the way to developing novel means for pest control, including baculoviruses, that rely upon suppressing host immune systems by strategically weakening insect defenses to improve pathogen (i.e. biocontrol agent) infection and virulence. Also, we expect that the above result will help to develop systems for enhanced insect control that may ultimately help to reduce transmission of insect vectored diseases of humans, animals and plants as well as provide mechanisms for suppression of insect populations that damage crop plants by direct feeding.
6
Ficht, Thomas, Gary Splitter, Menachem Banai e Menachem Davidson. Characterization of B. Melinensis REV 1 Attenuated Mutants. United States Department of Agriculture, dicembre 2000. http://dx.doi.org/10.32747/2000.7580667.bard.
Abstract (sommario):
Brucella Mutagenesis (TAMU) The working hypothesis for this study was that survival of Brucella vaccines was directly related to their persistence in the host. This premise is based on previously published work detailing the survival of the currently employed vaccine strains S19 and Rev 1. The approach employed signature-tagged mutagenesis to construct mutants interrupted in individual genes, and the mouse model to identify mutants with attenuated virulence/survival. Intracellular survival in macrophages is the key to both reproductive disease in ruminants and reticuloendothelial disease observed in most other species. Therefore, the mouse model permitted selection of mutants of reduced intracellular survival that would limit their ability to cause reproductive disease in ruminants. Several classes of mutants were expected. Colonization/invasion requires gene products that enhance host-agent interaction or increase resistance to antibacterial activity in macrophages. The establishment of chronic infection requires gene products necessary for intracellular bacterial growth. Maintenance of chronic infection requires gene products that sustain a low-level metabolism during periods characterized little or no growth (1, 2). Of these mutants, the latter group was of greatest interest with regard to our originally stated premise. However, the results obtained do not necessarily support a simplistic model of vaccine efficacy, i.e., long-survival of vaccine strains provides better immunity. Our conclusion can only be that optimal vaccines will only be developed with a thorough understanding of host agent interaction, and will be preferable to the use of fortuitous isolates of unknown genetic background. Each mutant could be distinguished from among a group of mutants by PCR amplification of the signature tag (5). This approach permitted infection of mice with pools of different mutants (including the parental wild-type as a control) and identified 40 mutants with apparently defective survival characteristics that were tentatively assigned to three distinct classes or groups. Group I (n=13) contained organisms that exhibited reduced survival at two weeks post-infection. Organisms in this group were recovered at normal levels by eight weeks and were not studied further, since they may persist in the host. Group II (n=11) contained organisms that were reduced by 2 weeks post infection and remained at reduced levels at eight weeks post-infection. Group III (n=16) contained mutants that were normal at two weeks, but recovered at reduced levels at eight weeks. A subset of these mutants (n= 15) was confirmed to be attenuated in mixed infections (1:1) with the parental wild-type. One of these mutants was eliminated from consideration due to a reduced growth rate in vitro that may account for its apparent growth defect in the mouse model. Although the original plan involved construction of the mutant bank in B. melitensis Rev 1 the low transformability of this strain, prevented accumulation of the necessary number of mutants. In addition, the probability that Rev 1 already carries one genetic defect increases the likelihood that a second defect will severely compromise the survival of this organism. Once key genes have been identified, it is relatively easy to prepare the appropriate genetic constructs (knockouts) lacking these genes in B. melitensis Rev 1 or any other genetic background. The construction of "designer" vaccines is expected to improve immune protection resulting from minor sequence variation corresponding to geographically distinct isolates or to design vaccines for use in specific hosts. A.2 Mouse Model of Brucella Infection (UWISC) Interferon regulatory factor-1-deficient (IRF-1-/- mice have diverse immunodeficient phenotypes that are necessary for conferring proper immune protection to intracellular bacterial infection, such as a 90% reduction of CD8+ T cells, functionally impaired NK cells, as well as a deficiency in iNOS and IL-12p40 induction. Interestingly, IRF-1-/- mice infected with diverse Brucella abortus strains reacted differently in a death and survival manner depending on the dose of injection and the level of virulence. Notably, 50% of IRF-1-/- mice intraperitoneally infected with a sublethal dose in C57BL/6 mice, i.e., 5 x 105 CFU of virulent S2308 or the attenuated vaccine S19, died at 10 and 20 days post-infection, respectively. Interestingly, the same dose of RB51, an attenuated new vaccine strain, did not induce the death of IRF-1-/- mice for the 4 weeks of infection. IRF-1-/- mice infected with four more other genetically manipulated S2308 mutants at 5 x 105 CFU also reacted in a death or survival manner depending on the level of virulence. Splenic CFU from C57BL/6 mice infected with 5 x 105 CFU of S2308, S19, or RB51, as well as four different S2308 mutants supports the finding that reduced virulence correlates with survival Of IRF-1-/- mice. Therefore, these results suggest that IRF-1 regulation of multi-gene transcription plays a crucial role in controlling B. abortus infection, and IRF-1 mice could be used as an animal model to determine the degree of B. abortus virulence by examining death or survival. A3 Diagnostic Tests for Detection of B. melitensis Rev 1 (Kimron) In this project we developed an effective PCR tool that can distinguish between Rev1 field isolates and B. melitensis virulent field strains. This has allowed, for the first time, to monitor epidemiological outbreaks of Rev1 infection in vaccinated flocks and to clearly demonstrate horizontal transfer of the strain from vaccinated ewes to unvaccinated ones. Moreover, two human isolates were characterized as Rev1 isolates implying the risk of use of improperly controlled lots of the vaccine in the national campaign. Since atypical B. melitensis biotype 1 strains have been characterized in Israel, the PCR technique has unequivocally demonstrated that strain Rev1 has not diverted into a virulent mutant. In addition, we could demonstrate that very likely a new prototype biotype 1 strain has evolved in the Middle East compared to the classical strain 16M. All the Israeli field strains have been shown to differ from strain 16M in the PstI digestion profile of the omp2a gene sequence suggesting that the local strains were possibly developed as a separate branch of B. melitensis. Should this be confirmed these data suggest that the Rev1 vaccine may not be an optimal vaccine strain for the Israeli flocks as it shares the same omp2 PstI digestion profile as strain 16M.