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Articles de revues sur le sujet ""Lhc proteins""
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Levin, Guy, et Gadi Schuster. « LHC-like Proteins : The Guardians of Photosynthesis ». International Journal of Molecular Sciences 24, no 3 (28 janvier 2023) : 2503. http://dx.doi.org/10.3390/ijms24032503.
Texte intégralRésumé :
The emergence of chlorophyll-containing light-harvesting complexes (LHCs) was a crucial milestone in the evolution of photosynthetic eukaryotic organisms. Light-harvesting chlorophyll-binding proteins form complexes in proximity to the reaction centres of photosystems I and II and serve as an antenna, funnelling the harvested light energy towards the reaction centres, facilitating photochemical quenching, thereby optimizing photosynthesis. It is now generally accepted that the LHC proteins evolved from LHC-like proteins, a diverse family of proteins containing up to four transmembrane helices. Interestingly, LHC-like proteins do not participate in light harvesting to elevate photosynthesis activity under low light. Instead, they protect the photosystems by dissipating excess energy and taking part in non-photochemical quenching processes. Although there is evidence that LHC-like proteins are crucial factors of photoprotection, the roles of only a few of them, mainly the stress-related psbS and lhcSR, are well described. Here, we summarize the knowledge gained regarding the evolution and function of the various LHC-like proteins, with emphasis on those strongly related to photoprotection. We further suggest LHC-like proteins as candidates for improving photosynthesis in significant food crops and discuss future directions in their research.
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Rochaix, Jean-David, et Roberto Bassi. « LHC-like proteins involved in stress responses and biogenesis/repair of the photosynthetic apparatus ». Biochemical Journal 476, no 3 (14 février 2019) : 581–93. http://dx.doi.org/10.1042/bcj20180718.
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AbstractLHC (light-harvesting complex) proteins of plants and algae are known to be involved both in collecting light energy for driving the primary photochemical reactions of photosynthesis and in photoprotection when the absorbed light energy exceeds the capacity of the photosynthetic apparatus. These proteins usually contain three transmembrane (TM) helices which span the thylakoid membranes and bind several chlorophyll, carotenoid and lipid molecules. In addition, the LHC protein family includes LHC-like proteins containing one, two, three or even four TM domains. One-helix proteins are not only present in eukaryotic photosynthetic organisms but also in cyanobacteria where they have been named high light-inducible proteins. These small proteins are probably the ancestors of the members of the extant LHC protein family which arouse through gene duplications, deletions and fusions. During evolution, some of these proteins have diverged and acquired novel functions. In most cases, LHC-like proteins are induced in response to various stress conditions including high light, high salinity, elevated temperature and nutrient limitation. Many of these proteins play key roles in photoprotection, notably in non-photochemical quenching of absorbed light energy. Moreover, some of these proteins appear to be involved in the regulation of chlorophyll synthesis and in the assembly and repair of Photosystem II and also of Photosystem I possibly by mediating the insertion of newly synthesized pigments into the photosynthetic reaction centers.
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Rathod, Mithun Kumar, Sreedhar Nellaepalli, Shin-Ichiro Ozawa, Hiroshi Kuroda, Natsumi Kodama, Sandrine Bujaldon, Francis-André Wollman et Yuichiro Takahashi. « Assembly Apparatus of Light-Harvesting Complexes : Identification of Alb3.1–cpSRP–LHCP Complexes in the Green Alga Chlamydomonas reinhardtii ». Plant and Cell Physiology 63, no 1 (1 octobre 2021) : 70–81. http://dx.doi.org/10.1093/pcp/pcab146.
Texte intégralRésumé :
Abstract The unicellular green alga, Chlamydomonas reinhardtii, contains many light-harvesting complexes (LHCs) associating chlorophylls a/b and carotenoids; the major LHCIIs (types I, II, III and IV) and minor light-harvesting complexes, CP26 and CP29, for photosystem II, as well as nine LHCIs (LHCA1–9), for photosystem I. A pale green mutant BF4 exhibited impaired accumulation of LHCs due to deficiency in the Alb3.1 gene, which encodes the insertase involved in insertion, folding and assembly of LHC proteins in the thylakoid membranes. To elucidate the molecular mechanism by which ALB3.1 assists LHC assembly, we complemented BF4 to express ALB3.1 fused with no, single or triple Human influenza hemagglutinin (HA) tag at its C-terminus (cAlb3.1, cAlb3.1-HA or cAlb3.1–3HA). The resulting complemented strains accumulated most LHC proteins comparable to wild-type (WT) levels. The affinity purification of Alb3.1-HA and Alb3.1–3HA preparations showed that ALB3.1 interacts with cpSRP43 and cpSRP54 proteins of the chloroplast signal recognition particle (cpSRP) and several LHC proteins; two major LHCII proteins (types I and III), two minor LHCII proteins (CP26 and CP29) and eight LHCI proteins (LHCA1, 2, 3, 4, 5, 6, 8 and 9). Pulse-chase labeling experiments revealed that the newly synthesized major LHCII proteins were transiently bound to the Alb3.1 complex. We propose that Alb3.1 interacts with cpSRP43 and cpSRP54 to form an assembly apparatus for most LHCs in the thylakoid membranes. Interestingly, photosystem I (PSI) proteins were also detected in the Alb3.1 preparations, suggesting that the integration of LHCIs to a PSI core complex to form a PSI–LHCI subcomplex occurs before assembled LHCIs dissociate from the Alb3.1–cpSRP complex.
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Brunner, Harald, et Wolfhart Rüdiger. « On the Expression of Several Lhc Genes in Garden Cress (Lepidium sativum L.) ». Zeitschrift für Naturforschung C 49, no 11-12 (1 décembre 1994) : 802–10. http://dx.doi.org/10.1515/znc-1994-11-1216.
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The polymerase chain reaction was used to prepare gene-specific probes for several Lhc genes coding for chlorophyll a/b-binding proteins of cress (Lepidium sativum L.). Due to the presence of about 150 basepairs of the coding region, the isolated clones could be attributed to Lhc a3 (1 clone), Lhc b1 (5 clones), Lhc b2 (1 clone) and Lhc b3 (1 clone) genes. Probes prepared from the 3′ non-coding regions of the clones did not cross-hybridize; they were specific for 3 different Lhc b1 transcripts and one each of Lhc b2, Lhc b3 and Lhc a 3 transcripts. The transcript levels were higher in leaves than in cotyledons of light-grown seedlings; they decreased significantly in cotyledons from week 1 to week 4. The levels of 2 Lhc b1 transcripts (detected with probes cd 1 and cd 2) changed from 1 week old cotyledons (30% c d l, 28% cd 2) to 3 months old leaves (14% c d l), 44% cd 2), stems (11% c d l, 56% cd 2) and fruits (15% cd 1, 62% cd 2, all values percent of total transcripts), whereas transcript levels of another Lhc b1 gene (detected with probe cd 3) and of a Lhc a 3 gene remained nearly constant. The level of Lhc b2 and Lhc b3 transcripts were 1 - 2 orders of magnitude smaller than those of the other Lhc transcripts. The data obtained with cress plants are compared with published data from other plants.
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Lan, Yanhong, Yao Song, Fei Zhao, Yu Cao, Dening Luo, Dairong Qiao, Yi Cao et Hui Xu. « Phylogenetic, Structural and Functional Evolution of the LHC Gene Family in Plant Species ». International Journal of Molecular Sciences 24, no 1 (28 décembre 2022) : 488. http://dx.doi.org/10.3390/ijms24010488.
Texte intégralRésumé :
Light-harvesting chlorophyll a/b-binding (LHC) superfamily proteins play a vital role in photosynthesis. Although the physiological and biochemical functions of LHC genes have been well-characterized, the structural evolution and functional differentiation of the products need to be further studied. In this paper, we report the genome-wide identification and phylogenetic analysis of LHC genes in photosynthetic organisms. A total of 1222 non-redundant members of the LHC family were identified from 42 species. According to the phylogenetic clustering of their homologues with Arabidopsis thaliana, they can be divided into four subfamilies. In the subsequent evolution of land plants, a whole-genome replication (WGD) event was the driving force for the evolution and expansion of the LHC superfamily, with its copy numbers rapidly increasing in angiosperms. The selection pressure of photosystem II sub-unit S (PsbS) and ferrochelatase (FCII) families were higher than other subfamilies. In addition, the transcriptional expression profiles of LHC gene family members in different tissues and their expression patterns under exogenous abiotic stress conditions significantly differed, and the LHC genes are highly expressed in mature leaves, which is consistent with the conclusion that LHC is mainly involved in the capture and transmission of light energy in photosynthesis. According to the expression pattern and copy number of LHC genes in land plants, we propose different evolutionary trajectories in this gene family. This study provides a basis for understanding the molecular evolutionary characteristics and evolution patterns of plant LHCs.
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Darr, S. C., S. C. Somerville et C. J. Arntzen. « Monoclonal antibodies to the light-harvesting chlorophyll a/b protein complex of photosystem II. » Journal of Cell Biology 103, no 3 (1 septembre 1986) : 733–40. http://dx.doi.org/10.1083/jcb.103.3.733.
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A collection of 17 monoclonal antibodies elicited against the light-harvesting chlorophyll a/b protein complex which serves photosystem II (LHC-II) of Pisum sativum shows six classes of binding specificity. Antibodies of two of the classes recognize a single polypeptide (the 28- or the 26- kD polypeptides), thereby suggesting that the two proteins are not derived from a common precursor. Other classes of antibodies cross-react with several polypeptides of LHC-II or with polypeptides of both LHC-II and the light-harvesting chlorophyll a/b polypeptides of photosystem I (LHC-I), indicating that there are structural similarities among the polypeptides of LHC-II and LHC-I. The evidence for protein processing by which the 26-, 25.5-, and 24.5-kD polypeptides are derived from a common precursor polypeptide is discussed. Binding studies using antibodies specific for individual LHC-II polypeptides were used to quantify the number of antigenic polypeptides in the thylakoid membrane. 27 copies of the 26-kD polypeptide and two copies of the 28-kD polypeptide were found per 400 chlorophylls. In the chlorina f2 mutant of barley, and in intermittent light-treated barley seedlings, the amount of the 26-kD polypeptide in the thylakoid membranes was greatly reduced, while the amount of 28-kD polypeptide was apparently not affected. We propose that stable insertion and assembly of the 28-kD polypeptide, unlike the 26-kD polypeptide, is not regulated by the presence of chlorophyll b.
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Droppa, Magdolna, Jiri Masojidek et Gábor Horváth. « Changes of the Polypeptide Composition in Thylakoid Membranes during Differentiation ». Zeitschrift für Naturforschung C 45, no 3-4 (1 avril 1990) : 253–57. http://dx.doi.org/10.1515/znc-1990-3-419.
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Changes in membrane polypeptide composition during greening of etiolated maize were investigated to confirm the existence of the developmental polypeptides of 12 - 15 kDa described recently in virescent soybean mutant [M. Droppa, M. L. Ghirardi, G. Horváth, and A. Melis, Biochim. Biophys. Acta 932, 138 - 145 (1988)]. These low molecular weight polypeptides were the most abundant proteins at the early stage of greening, but were largely absent from fully developed thylakoids. During greening the relative concentration of the 12-15 kDa polypeptides were inversely proportional to that of LHC II, suggesting a role of these polypeptides in the assembly of the LHC II and/or chloroplast development.
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Ke, Shanqiang, Chiwon W. Lee et Murray E. Duysen. « Influence of the rolC Gene on Proteins Associated with Stroma and Thylakoid Membranes of Chloroplasts in Transgenic Plants of Kentucky Bluegrass ». HortScience 32, no 3 (juin 1997) : 482D—482. http://dx.doi.org/10.21273/hortsci.32.3.482d.
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The effects of the expression of the rolC gene on protein accumulation in the chloroplasts of transgenic Kentucky bluegrass (Poa pratensis L.) were investigated. Coleoptile tissues excised from 3-day dark-grown seedlings were bombarded with tungsten particles coated with DNA of the engineered plasmid, pGA-GUSGF, containing the npt II, gus, and rolC genes. The tissues were cultured on callus induction medium, which consists of MS salts supplemented with 0.2 mg/L picloram, 0.01 mg/L naphthaleneacetic acid (NAA) 250 mg/L kanamycin, and 100 mM acetosyringone. The putative transformants were either albinos or variegated plants composed of white and green sections. These albino plants had little or no stroma-based 56-kDa and 14-kDa subunits of the suspected Rubisco proteins, which are expressed in response to genes in the nucleus and plastid, respectively. The albino plants also lacked the 110-kDa and 57–58-kDa, and 43, 47-kDa polypeptides in PS I, coupling factor, and PS II in thylakoid membranes, respectively. These proteins involved in photosynthesis are translated from plastidbased genes. No light-harvesting complex proteins (LHC) were observed in these albino plants. LHC genes are encoded in the nucleus. The thylakoid membrane proteins in the chloroplasts of the rolC transgenic variegated plants contained these proteins. Our data suggest that the nucleus and plastid gene products for plastid development are concomitantly impaired by expression of genes in the transgenic plants.
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Evans, JR. « Acclimation by the Thylakoid Membranes to Growth Irradiance and the Partitioning of Nitrogen Between Soluble and Thylakoid Proteins ». Functional Plant Biology 15, no 2 (1988) : 93. http://dx.doi.org/10.1071/pp9880093.
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Three characteristics of shade plants are reviewed. Firstly, they have relatively more chlorophyll b and the associated light-harvesting chlorophyll a/b-protein complex (LHC). Two currently accepted reasons for this are not supported by quantitative analysis. Instead, the reduced protein cost of complexing chlorophyll in LHC and the turnover of the 32 kDa herbicide binding protein are considered. Secondly, shade plants have low electron transport capacities per unit of chlorophyll. This is primarily related to a reduction in the amount of electron transport components such as the cytochrome f complex and the ATPase. The nitrogen cost of the thylakoid membranes per unit of light absorbed is thereby reduced, but the irradiance range over which light is used with high efficiency is also reduced. Thirdly, shade plants have less RuP2 carboxylase and other soluble proteins for a given amount of chlorophyll. However, while the ratio of RuP2 carboxylase protein to thylakoid protein declined, the ratio of the RuP2 carboxylase activity to electron transport activity increased. For several species, the relationship between the rate of CO2 assimilation and leaf nitrogen content depends on the irradiance during growth.
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Wu, Guangxi, Lin Ma, Cai Yuan, Jiahao Dai, Lai Luo, Roshan Sharma Poudyal, Richard T. Sayre et Choon-Hwan Lee. « Formation of light-harvesting complex II aggregates from LHCII–PSI–LHCI complexes in rice plants under high light ». Journal of Experimental Botany 72, no 13 (3 mai 2021) : 4938–48. http://dx.doi.org/10.1093/jxb/erab188.
Texte intégralRésumé :
Abstract During low light- (LL) induced state transitions in dark-adapted rice (Oryza sativa) leaves, light-harvesting complex (LHC) II become phosphorylated and associate with PSI complexes to form LHCII–PSI–LHCI supercomplexes. When the leaves are subsequently transferred to high light (HL) conditions, phosphorylated LHCII complexes are no longer phosphorylated. Under the HL-induced transition in LHC phosphorylation status, we observed a new green band in the stacking gel of native green–PAGE, which was determined to be LHCII aggregates by immunoblotting and 77K chlorophyll fluorescence analysis. Knockout mutants of protein phosphatase 1 (PPH1) which dephosphorylates LHCII failed to form these LHCII aggregates. In addition, the ability to develop non-photochemical quenching in the PPH1 mutant under HL was less than for wild-type plants. As determined by immunoblotting analysis, LHCII proteins present in LHCII–PSI–LHCI supercomplexes included the Lhcb1 and Lhcb2 proteins. In this study, we provide evidence suggesting that LHCII in the LHCII–PSI–LHCI supercomplexes are dephosphorylated and subsequently form aggregates to dissipate excess light energy under HL conditions. We propose that this LHCII aggregation, involving LHCII L-trimers, is a newly observed photoprotective light-quenching process operating in the early stage of acclimation to HL in rice plants.
Thèses sur le sujet ""Lhc proteins""
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Engelken, Johannes [Verfasser]. « Evolution of the extended LHC protein superfamily in photosynthesis / Johannes Engelken ». Konstanz : Bibliothek der Universität Konstanz, 2010. http://d-nb.info/1023210401/34.
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Hey, Daniel. « Die Funktion LHC-ähnlicher Proteine in der Assemblierung der Photosysteme und der Regulation der Chlorophyllbiosynthese ». Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19963.
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Die pflanzliche Light-harvesting complex-Proteinfamilie besteht aus Proteinen mit vielfältigen Funktionen. Dabei ist die Funktion der Light-harvesting-like 3-Proteine (LIL3) sowie der One-helix-Proteine (OHPs) weitestgehend unbekannt. Im Rahmen dieser Arbeit wurde gezeigt, dass LIL3 nicht nur mit der Geranylgeranyl-Reduktase (CHLP), sondern auch mit der Protochlorophyllid-Oxidoreduktase (POR) interagiert. Sowohl CHLP als auch POR werden über die Interaktion zu LIL3 an die Thylakoidmembran gebunden und dadurch stabilisiert. Beide Enzyme liefern die direkten Vorstufen für den von der Chlorophyll-Synthase (CHLG) katalysierten finalen Chlorophyll-Syntheseschritt. Neben der Bestätigung der bereits früher gezeigten Chlorophyllbindung von LIL3 konnte eine Affinität zu den späten Intermediaten der Chlorophyllbiosynthese Proto IX, MgP, MgPMME und Pchlid nachgewiesen werden. Die größte Affinität bestand dabei gegenüber dem Substrat von POR, Pchlid. Basierend auf diesen Erkenntnissen wird LIL3 als Regulator der späten Chlorophyllbiosynthese-Schritte vorgeschlagen: LIL3 transportiert Substrate zwischen den Enzymen und ermöglicht durch die Bindung von CHLP und POR die Synthese der Chlorophyll-Edukte in räumlicher Nähe. Dadurch wird die Versorgung von CHLG mit dessen Edukten favorisiert. Beide OHP-Varianten (OHP1/2) bilden ausschließlich Heterodimere und binden Chlorophyll sowie Carotinoide im Verhältnis 3:1. Die Pigmentbindung basiert auf den konservierten Aminosäuren im Chlorophyllbindemotiv. An das OHP1-OHP2-Dimer bindet der PSII-Assemblierungsfaktor HCF244 und wird dadurch an der Membran verankert. HCF244 stabilisiert das OHP-Heterodimer und beide OHPs stabilisieren sich gegenseitig. Der heterotrimere OHP1-OHP2-HCF244-Komplex ist für die D1-Synthese wesentlich. Es wird vermutet, dass die OHPs an der co-translationalen Beladung von (p)D1 mit Pigmenten beteiligt sind sowie frühe Assemblierungsintermediate von PSII vor überschüssiger Anregungsenergie schützen.The plant light-harvesting complex protein family comprises different members with a variety of functions. However, the function of the light-harvesting-like 3 proteins (LIL3) as well as the one-helix proteins (OHPs) is largely unknown. In this thesis, an interaction of LIL3 not only with geranylgeranyl-reductase (CHLP), but also with protochlorophyllide-oxidoreductase (POR) could be established. LIL3 tethers CHLP and POR to the thylakoid membrane, thereby conferring stability to both enzymes. Both CHLP and POR are synthesizing the direct chlorophyll precursors which are combined to chlorophyll by the subsequent chlorophyll synthase (CHLG). In addition to the chlorophyll binding ability of LIL3 reported earlier, an affinity of LIL3 towards the chlorophyll biosynthesis intermediates Proto IX, MgP, MgPMME, and Pchlide could be shown. Interestingly, the highest affinity of LIL3 was exerted towards Pchlide which is the substrate of POR. Therefore, LIL3 is postulated to shuffle the intermediates between enzymes and brings CHLP and POR in close proximity, which may help to supply CHLG with its substrates. Regarding the function of the OHPs an exclusive heterodimer formation of both the OHP1 and OHP2 variants could be shown. The OHP1-OHP2-heterodimer is able to bind chlorophyll and carotenoids in an approximate 3:1 ratio and pigment binding depends on dimer formation as well as the presence of the conserved amino acids in the chlorophyll binding motif. The PSII-assembly factor HCF244 is anchored to the thylakoid membrane by binding to both OHPs, thereby stabilizing the OHP-heterodimer. The heterotrimeric OHP1-OHP2-HCF244-complex is essential for D1 biosynthesis, although the exact molecular function of HCF244 is still unknown. It is suggested that the OHP-dimer is responsible for co-translational loading of (p)D1 with pigments as well as photoprotection of early PSII assembly intermediates.
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Lee, Sarah Angeline. « Curcumin Protects against Renal Ischemia by Activating the Unfolded Protein Response and Inducing HSP70 ». Yale University, 2009. http://ymtdl.med.yale.edu/theses/available/etd-04062009-215154/.
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The purpose of this study was to establish whether curcumin protects renal proximal tubule cells against ischemic injury, determine whether this postulated cytoprotective effect is mediated through the upregulation of HSP70, and investigate whether the mechanism by which curcumin induces HSP70 expression and confers its protective effect is through activation of the Unfolded Protein Response. LLC-PK1 cells were cultured on collagen-coated filters to mimic conditions of in vivo renal proximal tubule cells and induce cell polarization. Injury with and without curcumin treatment was studied by using chemically-induced ATP-depletion which mimics renal ischemic injury. Cell injury was assessed using a TUNEL assay in order to evaluate DNA cleavage associated with ischemia-induced apoptosis and actin staining used to assess cytoskeletal disruption. Renal ischemic damage was further investigated by determining detachment of the Na-K ATPase from the basolateral membrane, which represents loss of cell polarity. Cells were incubated with curcumin in a dose- and time-response fashion and subsequent levels of HSP70 expression were assessed. Cells were then incubated with AEBSF, an inhibitor of the Unfolded Protein Response (UPR) and HSP70 and BiP/GRP78 (an ER resident chaperone that is upregulated by the UPR) expression levels were evaluated. Results demonstrated that treatment with curcumin during two hours of injury results in significantly less injury-related apoptosis and cytoskeletal disruption compared to control injured cells. It was demonstrated that curcumin induces HSP70 in both a dose- and time-response fashion. Moreover, curcumin treatment resulted in profound stabilization of Na-K ATPase on the basolateral membranes as there was significantly less Na-K ATPase detachment in cells treated with curcumin during two hours of injury compared to control injured cells. Finally, treatment with AEBSF inhibited HSP70 upregulation in curcumin-treated cells as well as inhibiting the GRP78 over-expression otherwise demonstrated in curcumin-treated cells. Protection of proximal tubule cells against renal ischemic injury by curcumin was therefore indicated to be mediated by the activation of the UPR through which HSP70 is upregulated. Curcumins activation of the UPR and induction of HSP70 explains the stabilization of Na-K ATPase on the cytoskeleton and also provides a potential mechanism explaining many of curcumins therapeutic and protective qualities.
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Bradburne, James Andrew. « Gibberellic acid and reflected light mediated changes in the content of light - harvesting chlorophyll protein (LHC - II) ». Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/25394.
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Benson, Samuel Lee. « Light harvesting and state transitions in Arabidopsis thaliana deficient in Lhca proteins ». Thesis, University of Sheffield, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289600.
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Worthen, Denise Lynne. « Lactose binding to the E. coli symport protein Lac permease ». Diss., Pasadena, Calif. : California Institute of Technology, 1989. http://resolver.caltech.edu/CaltechTHESIS:11242009-093118312.
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Pohl, Antje Heide. « Lipid transport by ABC proteins ». Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2002. http://dx.doi.org/10.18452/14784.
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In eukaryotischen Zellen sind die Lipidspezies häufig asymmetrisch zwischen den Hälften der Plasmamembran verteilt. Insbesondere Phosphatidylserin (PS) weist oft eine ausgeprägte transversale Asymmetrie auf, da es fast ausschliesslich auf die innere Hälfte der Plasmamembran beschränkt ist. In den letzten Jahren wurden mehrere Proteine diskutiert, die Lipide zwischen den Membranhälften transportieren und möglicherweise die transversale Lipidasymmetrie sowie damit verbundene Zelleigenschaften beeinflussen. Im Mittelpunkt der vorliegenden Promotion steht der Auswärtstransport fluoreszierender (C6-NBD-) Lipid-Analoga und endogener Lipide durch das Multidrug Resistance 1 P-Glycoprotein (MDR1 Pgp), das der ATP Binding Cassette (ABC) Transporter Superfamilie angehört. Interessanter Weise wird für MDR1 Pgp eine ungewöhnlich breite Substratspezifität angenommen. Das anionische Lipid PS war hier von besonderem Interesse, obgleich es in vorhergehenden Arbeiten nicht als MDR1 Pgp Substrat betrachtet wurde. Der Auswärtstransport von Phosphatidylcholin-, Phosphatidylethanolamin-, Glucosylceramid- und Sphingomyelin-Analoga durch MDR1 Pgp konnte in einer humanen Magenkarzinomlinie (EPG85-257), die MDR1 überexprimiert, mittels Fluoreszenzspektroskopie bestätigt werden. Zudem legt die verringerte Akkumulation von Diacylglycerol- und Ceramid-Analoga den Transport dieser Lipidspezies durch MDR1 Pgp nahe. Im Anschluß an die intrazelluläre Markierung mit C6-NBD-PS mittels eines neuen Verfahrens konnte der signifikant erhöhte Auswärtstransport dieses Analogons in MDR1 überexprimierenden Zellen durch Verwendung spezifischer Inhibitoren MDR1 Pgp zugeschrieben werden. In flusscytometrischen Versuchen war die Exponierung von endogenem PS auf der äusseren Membranhälfte von MDR1 überexprimierenden Zellen signifikant höher als in Kontrollzellen. Verringerung der PS-Exponierung durch einen Inhibitor von MDR1 Pgp deutet auf den Transport von endogenem PS durch MDR1 Pgp hin. Zusätzlich wurde hier der Transport von C6-NBD-PS in vier weiteren Zellinien mit verschiedener Spezies- und Gewebezugehörigkeit charakterisiert, die unterschiedliche Mengen an MDR1 Pgp synthetisieren. Wie Experimente in einer BCRP überexprimierenden EPG85-257-Sublinie nahelegen, ist ausser MDR1 Pgp möglicherweise ebenfalls der ABC Halb-Transporter Breast Cancer Resistance Protein (BCRP) am Transport von C6-NBD-PS und an der verstärkten Exponierung von endogenem PS beteiligt.In eukaryotic cells, the lipid species are frequently distributed asymmetrically between the plasma membrane leaflets. Phosphatidylserine (PS), in particular, often exhibits a distinct transverse asymmetry, being restricted almost exclusively to the inner leaflet. In the past years, several proteins were suggested to transport lipids between the leaflets of a membrane, and to potentially influence transverse lipid asymmetry and related cell properties. This thesis focuses on outward transport of fluorescent (C6-NBD-) lipid analogs and endogenous lipids by the Multidrug Resistance 1 P-Glycoprotein (MDR1 Pgp), a member of the ATP binding cassette (ABC) transporter superfamily. Interestingly, MDR1 Pgp has been suggested to exhibit an unusually broad substrate specificity. Here, the anionic PS was of particular concern, although previously reported not to be an MDR1 Pgp substrate. In a human gastric carcinoma cell line (EPG85-257) overexpressing MDR1, outward transport of phosphatidylcholine, phosphatidylethanolamine, glucosylceramide and sphingomyelin analogs via MDR1 Pgp was confirmed using fluorescence spectroscopy. In addition, decreased accumulation of analogs of diacylglycerol and ceramide suggest MDR1 Pgp mediated transport of these lipid species. Upon intracellular labelling with C6-NBD-PS using a novel approach, significantly increased outward transport of this analog in MDR1 overexpressing cells could be attributed to MDR1 Pgp by employing specific inhibitors. In a flow cytometry setup, the exposure of endogenous PS on the outer plasma membrane leaflet was significantly elevated in MDR1 overexpressing cells compared to controls. Reduction of PS exposure by an MDR1 Pgp inhibitor suggests transport of endogenous PS by MDR1 Pgp. Transport of C6-NBD-PS was furthermore characterized here in four additional cell lines of different species and tissue origin with varying synthesis levels of MDR1 Pgp. Besides MDR1 Pgp, the ABC half-size transporter Breast Cancer Resistance Protein (BCRP) is possibly also involved in transport of C6-NBD-PS and in increased exposure of endogenous PS, as found in a BCRP overexpressing EPG85-257 subline.
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Kaiser, Abigail M. « Localization of Five Target Proteins in Tachyzoites of Toxoplasma gondii ». Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7820.
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Five target genes were selected in Toxoplasma gondii tachyzoites for localization studies. These five genes, detected through proteomics studies, included TgME49_227450, TgME49_223080, TgME49_262390, TgME49_230940, and TgME49_269620. Localization of these five target proteins is a first step to confirm their interaction with TgCrk2 and understand their function and role in TgCrk2 regulation of the tachyzoite cell cycle. Gene models for the targets were analyzed using ToxoDB and ApE analysis tools. Endogenous tagging constructs were created for each target. Transgenic parasites were created. Finally, localization analysis of the target proteins in tachyzoites was completed using immunofluorescent microscopy following. One protein was found to be nuclear, two were located in the cytoplasm, and two were unable to be analyzed. Future research should be completed in order to prove these putative interactors are really correlated with TgCrk2 through Co-immunoprecipitation.
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Kesiry, Riad. « GRP78/BiP is Involved in Ouabain-induced Endocytosis of the Na/K-ATPase in LLC-PK1 Cells ». University of Toledo Health Science Campus / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=mco1096302498.
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Bianchi, Allison A. « Characterization and application of Escherichia coli stress promoter-lacZ fusions / ». Thesis, Connect to this title online ; UW restricted, 1999. http://hdl.handle.net/1773/8072.
Texte intégralLivres sur le sujet ""Lhc proteins""
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Lee, See-Lai. Studies on regulation of expression of the verotoxin operon and of the 39K replication protein of plasmid pFA3 using gene and operon fusions to lac Z. Ottawa : National Library of Canada, 1990.
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Paloma, Salvador Clavel, Ramon Viladot Perice et Oriol Cohi Riambau. Ortesis y Protesis del Apar. Loc. 1 Columna Verteb. Masson, 1999.
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Paloma, Salvador Clavel, Ramon Viladot Perice et Oriol Cohi Riambau. Ortesis y Protesis del Apar. Loc. 2.2. Extrem INF. Masson, 1999.
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Dow, Bonnie J. Magazines and the Marketing of the Movement. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252038563.003.0004.
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This chapter focuses on the March 18, 1970, sit-in at Ladies' Home Journal (LHJ), a crucial episode in feminist media activism that had dramatic internal and external consequences for women's liberation. Conceived as a radical action by a small group of women incensed at the demeaning portrayal of women in a publication that touted itself as “the magazine women believe in,” the LHJ protest was an unpredictable success, precipitating significant changes in editorial and employment practices at women's magazines. That outcome was the product of several factors, including the emphases of the print and broadcast coverage of the LHJ events as well as the action's timing among a wave of protests and discrimination complaints launched in 1970 by women employees of major media institutions. Equally important was the recognition of the magazine's editors—and those of their sister publications—that incorporating and commodifying women's liberation was more profitable than resisting it, processes that would soon escalate across all forms of mass media.
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Burt, Ramsay. The Politics of Speaking about the Body. Sous la direction de Rebekah J. Kowal, Gerald Siegmund et Randy Martin. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199928187.013.16.
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This chapter argues that some of the more radical developments in theatre dance initiated by Steve Paxton, Yvonne Rainer, Deborah Hay, and others in the 1960s and 1970s were supported by problematically dualistic ways of speaking and writing about “the body.” By valuing the rational “mind” over the supposedly irrational “body,” the normative hierarchy was inverted. The chapter discusses the way in which this concern with “the body” in minimalist performances by Yvonne Rainer became political in the context of protests against the Vietnam War. The new sensitivity to corporeality that emerged from minimalism then formed the basis for Hay’s Circle Dances and Paxton’s Magnesium. Drawing on Boltanski and Chiapello’s discussion of the political critique of the 1960s and 1970s counterculture, and Jean-Luc Nancy and Giorgio Agamben’s discussion of community, the chapter analyses the politics underlying the way that these dance practices involved talking and writing about “the body.”
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Bogue, Ronald. Deleuze and Roxy : The Time of the Intolerable and Godard’s Adieu au langage. Edinburgh University Press, 2018. http://dx.doi.org/10.3366/edinburgh/9781474422734.003.0015.
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Focusing specifically on Jean-Luc Godard’s experimental 3-D outing, Adieu au langage (2014), this chapter equates becoming-animal (manifested through Godard’s dog, Roxy) with the time of the intolerable, a crisis in the action-image which precludes any absorption of affect within the sensory-motor schema. In this sense, Roxy becomes an immanent, animistic force that remakes the world (and by extension, as in all of Godard’s films, cinema itself) into a protean force of becoming, where even 3-D bifurcates and deterritorialises as a new form of machinic fabulation. In the case of the intolerable, where our sensory-motor schema is allowed to jam or break, a different type of image appears, what Deleuze calls a pure optical-sound image: ‘opsigns’ and ‘sonsigns’, images where the seen and heard no longer extend into action. In Adieu au langage, Godard’s use of 3D also offers a new kind of time-image, a lectosign (a visual image which must be ‘read’ as much as seen) that requires the eye’s negotiation of conflicting points of attention within the shot, thereby inducing crisis and the intolerable within the image itself.
Chapitres de livres sur le sujet ""Lhc proteins""
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Anandan, Shivanthi, et J. Philip Thornber. « Isolation of the LHC I complex of Barley Containing Multiple Pigment-Proteins ». Dans Current Research in Photosynthesis, 1245–48. Dordrecht : Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0511-5_288.
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Oberschmidt, O., S. Kim, J. M. McGrath, M. M. Jansco, R. Bassi, B. Piechulla et E. Pichersky. « An Investigation of the LHC Family of Genes and Proteins in the Homosporous Fern Ceratopteris richardii ». Dans Photosynthesis : from Light to Biosphere, 65–68. Dordrecht : Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-009-0173-5_12.
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Freiberg, Arvi, Rein Ruus et Kõu Timpmann. « Exciton lineshapes of LH2 photosynthetic antenna proteins ». Dans Spectroscopy of Biological Molecules : New Directions, 115–18. Dordrecht : Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4479-7_48.
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Yang, Ziping, Wenkui Li, Harold T. Smith et Francis L. S. Tse. « LC-MS Bioanalysis of Proteins ». Dans Handbook of LC-MS Bioanalysis, 601–5. Hoboken, NJ, USA : John Wiley & Sons Inc., 2013. http://dx.doi.org/10.1002/9781118671276.ch47.
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Nagase, Toshihiko, Toshihiro Sugiyama, Shigeki Higashiyama, Daitoku Sakamuro, Sumio Kawata, Seiichiro Tarui et Naoyuki Taniguchi. « Identifications of Carbonic Anhydrase III and Triosephosphate Isomerase in the Liver Proteins in LEC Rats on Two-Dimensional Gel Electrophoresis ». Dans The LEC Rat, 175–84. Tokyo : Springer Japan, 1991. http://dx.doi.org/10.1007/978-4-431-68153-3_20.
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Boßmann, B., S. Jansson et J. Knoetzel. « Chlorina-Mutants of Barley Lacking Specific LHCA-Proteins ». Dans Photosynthesis : from Light to Biosphere, 135–38. Dordrecht : Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-009-0173-5_29.
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Altman, Russ B., Ruth Pachter et Oleg Jardetzky. « Determination of Structural Uncertainty from NMR and Other Data : The Lac Repressor Headpiece ». Dans Protein Structure and Engineering, 79–95. Boston, MA : Springer US, 1989. http://dx.doi.org/10.1007/978-1-4684-5745-2_7.
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Hind, Geoffrey, et Sean Coughlan. « Reconstitution of LHC Phosphorylation by a Protein Kinase Isolated from Spinach Thylakoids ». Dans Progress in Photosynthesis Research, 801–4. Dordrecht : Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3535-8_189.
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Engelken, Johannes, Christiane Funk et Iwona Adamska. « The Extended Light-Harvesting Complex (LHC) Protein Superfamily : Classification and Evolutionary Dynamics ». Dans Functional Genomics and Evolution of Photosynthetic Systems, 265–84. Dordrecht : Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-1533-2_11.
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Kaptein, Robert, Rolf Boelens et Rolf M. J. N. Lamerichs. « NMR studies of protein-DNA recognition. The interaction of lac repressor headpiece with operator DNA ». Dans Protein-Nucleic Acid Interaction, 35–59. London : Macmillan Education UK, 1989. http://dx.doi.org/10.1007/978-1-349-09871-2_3.
Texte intégralActes de conférences sur le sujet ""Lhc proteins""
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de Vries, C. J. M., N. K. Veerman et H. Pannekoek. « ARTIFICIAL EXON SHUFFLING : CONSTRUCTION OF HYBRID cDNAS CONTAINING DOMAINS OF TISSUE-TYPE PLASMINOGEN ACTIVATOR (T-PA) AND UROKINASE (u-PA) ». Dans XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643940.
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The intriguing finding that functions of t-PA coincide with structural domains and that these domains occur in related proteins, has been the basis to construct hybrid proteins by artificial exon shuffling to prove the conservation of functions in the shuffled domains. The heavy chain (Hch) of t-PA mediates both binding to fibrin and stimulation of plasminogen activator activity via its Finger- and Kringle-2 domain, whereas the light chain (Lch) contains the serine protease moiety of the protein. The Hch of u-PA is very homologous to the Lch of t-PA, but exhibits a higher plasminogen activator activity. This activity of u-PA is not stimulated by fibrin. We employed the ‘M13 in vitro outlooping’ technique to fuse the Hch of t-PA cDNA and the Hch of u-PA cDNA, to create two different hybrid cDNAs. On one hybrid cDNA, the t-PA and the u-PA sequences are coupled precisely at the exon-intron boundaries of the corresponding genes, while the other hybrid cDNA lacks a u-PA segment at the junction, encoding 13 amino acids of u-PA. The hybrid cDNAs were transiently expressed in mouse Ltk- cells and the recombinant proteins were characterized. The plasminogen activator activity of these proteins was determined in an indirect amidolytic assay, using plasminogen and the chromogenic substrate S2251. As anticipated, the activity of both t-PA/u-PA hybrid proteins is stimulated by fibrin, however, not to the same extent as t-PA. Remarkably, we found a decreased inhibition of the hybrid proteins by the endothelial plasminogen activator inhibitor (PAI-1) as compared to t-PA and u-PA, although stable complexes between the hybrid proteins and the inhibitor are formed. We conclude that functions of structural domains are maintained during exon shuffling
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Ide, J. P., D. R. Klug, W. Kuhlbrandt et G. Porter. « Detergent effects upon the picosecond dynamics of higher plant light harvesting chlorophyll complex (LHC). » Dans International Conference on Ultrafast Phenomena. Washington, D.C. : Optica Publishing Group, 1986. http://dx.doi.org/10.1364/up.1986.mf1.
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The light-harvesting chlorophyll a/b protein complex (LHC) has been shown to form crystalline arrays in vitro. These arrays have P321 symmetry. The unit cell is composed of trimeric protein oligomers arranged with a 3-fold symmetry axis running centrally through each complex[1]. Each polypeptide has an apparent molecular weight of 25–27kd within which are bound 6-11 chlorophyll molecules.
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Chachisvilis, M., T. Pullerits, M. R. Jones, C. N. Hunter et V. Sundstrom. « Coherent Nuclear Motions and Exciton State Dynamics in Photosynthetic Light-Harvesting Pigments. » Dans International Conference on Ultrafast Phenomena. Washington, D.C. : Optica Publishing Group, 1994. http://dx.doi.org/10.1364/up.1994.tub.6.
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Introduction The light-harvesting (LH) pigment-proteins of photosynthetic purple bacteria have been extensively studied with picosecond [1] and now recently with femtosecond [2] pulses. These investigations have helped to make these pigments to the probably best studied and characterized LH systems. Several bacteria, including the presently studied species Rhodobacter sphaeroides, contain two types of LH pigments, a core LH1 antenna surrounding the photochemical reaction centers and a more peripheral LH2 antenna. Both these LH pigments are believed to be organized in small minimum units of 2-4 polypeptides holding about the same number of chromophores, which aggregate to form the network of the intact antenna. Energy transfer between minimum units is believed to occur in a non-coherent hopping fashion. Interaction within a unit is probably quite strong and spectral evidence suggest that it should be characterized as strong exciton interaction leading to the formation of delocalized exciton states. In this report we will mainly be concerned with the ultrafast dynamics within such a minimum unit.
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Pannekok, H., A. J. Van Zonneveid, C. J. M. de vries, M. E. MacDonald, H. Veerman et F. Blasi. « FUNCTIONAL PROPERTIES OF DELETION-MUTANTS OF TISSUE-TYPE PLASMINOGEN ACTIVATOR ». Dans XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643724.
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Over the past twenty-five years, genetic methods have generated a wealth of information on the regulation and the structure-function relationship of bacterial genes.These methods are based on the introduction of random mutations in a gene to alter its function. Subsequently, genetic techniques cure applied to localize the mutation, while the nature of the impairedfunction could be determined using biochemical methods. Classic examples of this approach is now considered to be the elucidation of the structure and function of genes, constituting the Escherichia coli lactose (lac) and tryptophan (trp) operons,and the detailed establishment of the structure and function of the repressor (lacl) of the lac operon. Recombinant DNA techniques and the development of appropriate expression systems have provided the means both to study structure and functionof eukaryotic (glyco-) proteins and to create defined mutations with a predestinedposition. The rationale for the construction of mutant genes should preferentiallyrely on detailed knowledge of the three-dimensional structure of the gene product.Elegant examples are the application of in vitro mutagenesis techniques to substitute amino-acid residues near the catalytic centre of subtilisin, a serine proteasefrom Bacillus species and to substituteanamino acid in the reactive site (i.e. Pi residue; methionine) of α-antitrypsin, a serine protease inhibitor. Such substitutions have resulted into mutant proteins which are less susceptible to oxidation and, in some cases, into mutant proteins with a higher specific activity than the wild-type protein.If no data are available on the ternary structure of a protein, other strategies have to be developed to construct intelligent mutants to study the relation between the structure and the function of a eukaryotic protein. At least for a number of gene families, the gene structure is thought to be created by "exon shuffling", an evolutionary recombinational process to insert an exon or a set of exons which specify an additional structural and/or functional domain into a pre-existing gene. Both the structure of the tissue-type plasminogen activator protein(t-PA) and the t-PA gene suggest that this gene has evolved as a result of exon shuffling. As put forward by Gilbert (Science 228 (1985) 823), the "acid test"to prove the validity of the exon shuffling theory is either to delete, insert or to substitute exon(s) (i.e. in the corresponding cDNA) and toassay the properties of the mutant proteins to demonstrate that an exon or a set of adjacent exons encode (s) an autonomousfunction. Indeed, by the construction of specific deletions in full-length t-PA cDNA and expression of mutant proteins intissue-culture cells, we have shown by this approach that exon 2 of thet-PA gene encodes the function required forsecretion, exon 4 encodes the "finger" domain involved in fibrin binding(presumably on undegraded fibrin) and the set of exons 8 and 9 specifies kringle 2, containing a lysine-binding sit(LBS) which interacts with carboxy-terminal lysines, generated in fibrin after plasmic digestion. Exons 10 through 14 encode the carboxy-ter-minal light chain of t-PA and harbor the catalytic centre of the molecule and represents the predominant "target site" for the fast-acting endothelial plasminogen activator inhibitor (PAI-1).As a follow-up of this genetic approach to construct deletion mutants of t-PA, we also created substitution mutants of t-PA. Different mutants were constructed to substitute cDNA encoding thelight chain of t-PA by cDNA encoding the B-chain of urokinase (u-PA), in order to demonstrate that autonomous structural and functional domains of eitherone of the separate molecules are able toexert their intrinsic properties in a different context (C.J.M. de Vries et al., this volume). The possibilities and the limitations of this approach to study the structure and the function of t-PA and of other components of the fibrinolytic process will be outlined.
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Zambalde, Erika Pereira, Ana Carolina Rodrigues, Rubens Silveira Lima, Enilze Maria Souza Fonseca Ribeiro et Jaqueline Carvalho Oliveira. « TLNC-UC.147, A NOVEL LONG RNA (lncRNA) FROM AN ULTRACONSERVED REGION AS POTENTIAL BIOMARKER IN LUMINAL A BREAST CANCER ». Dans Scientifc papers of XXIII Brazilian Breast Congress - 2021. Mastology, 2021. http://dx.doi.org/10.29289/259453942021v31s1052.
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Introduction: Long RNAs are non-coding RNAs with more than 200 nucleotides in length, with essential regulatory roles in several biological processes, including in breast cancer (BC). The human genome contains 481 ultraconserved regions, which are genomic stretches of over 200 base pairs conserved among humans, rats, and mice. Most of these regions are transcriptionally active (T-UCRs), and several are differentially expressed in tumors. Some T-UCRs have been functionally characterized, but few have been associated with BC. Objectives: In this study, we aimed to expand the knowledge of T-UCRs in BC and characterize the lnc-uc.147, a long RNA transcribed from an ultraconserved region. Methods: We evaluated the expression level of 481 T-UCRs and their association with clinical parameters from TCGA data. For confirmation, 102 Brazilian BC samples were analyzed by RT-qPCR. Cytosolic and nuclear cell fractions and RT-qPCRs were done to determine the cell compartment of the transcript. Northern blotting and RACE were performed to determine the sequence and precise size of lnc-uc.147. Using two luminal cell lines (CAMA and BT474), a siRNA-based approach was applied to investigate the effects of lnc-uc.147 knockdown in cell viability, colony formation, and apoptosis level. To understand the interactions of lnc-uc.147 and proteins, we performed a pull-down assay. Results: Using TCGA (The Cancer Genome Atlas) data, we found 302 T-UCRs related to clinical features in BC: 43% were associated with molecular subtypes, 36% with estrogen-receptor positivity, 17% with HER2 expression, 12% with stage, and 10% with overall survival. We found that uc.147 is highly expressed in luminal A and B patients, which was also confirmed in Brazilian samples. For luminal A, a subtype usually associated with better prognosis, high uc.147 expression was associated with a poor prognosis and suggested as an independent prognostic factor. The lncRNA from uc.147 (lnc-uc.147) is in the nucleus. Northern blotting results show that uc.147 is a 2,8 kb monoexonic transcript. The silencing of uc.147 increases apoptosis, arrests the cell cycle and reduces cell viability and colony formation in luminal BC cell lines. Additionally, we identified 19 proteins that interact with uc.147 through mass spectrometry. These proteins are mainly involved in cytoskeletal and centrosome organization as well as in epithelial-mesenchymal transition. Conclusions: We show herein evidence that neoplastic BC cells exhibit a unique expression profile of T-UCRs. This study characterized the lnc-uc.147, a transcript that has never been described before. Indeed, lnc-uc.147 has an oncogenic effect in the luminal BC cell line and can interact with proteins. Furthermore, uc.147 has the potential as a BC prognostic marker in luminal patients.
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Lamort, A., S. Weiß, I. Lillis, V. Armenis, K. Arendt, M. Pepe, L. Klotz et al. « Tumor-derived granulocyte chemotactic protein 2 cooperates with neutrophil proteinase 3 to drive lung adenocarcinoma ». Dans ERS International Congress 2018 abstracts. European Respiratory Society, 2018. http://dx.doi.org/10.1183/13993003.congress-2018.lsc-1118.
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Mallakin, Ali, Kazushi Inoue et Martin Guthold. « In-Situ Quantitative Analysis of Tumor Suppressor Protein (hDMP1) Using a Nanomechanical Cantilever Beam ». Dans ASME 2005 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/detc2005-84503.
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This study is focused on testing “immuno-sensors” of micro-cantilever beams for the purpose of future design of high-throughout bioassays. We currently study the aberrant expression, deletion and mutation of hDMP1 (Human DMP1) in human lung cancer. Lung cancer is the leading cause of cancer deaths among men and women in North America. There are four major histological subtypes of human lung cancer: small-cell carcinoma (SCC), adenocarcinoma (AC), squamous cell carcinoma (SCC), and large-cell carcinoma (LCC). The hDMP1 locus is localized on chromosome 7q21, a region frequently deleted as part of the 7q-minus and monosomy 7 abnormalities of acute myeloid leukemia and myelodysplastic syndrome. Recent data demonstrate the critical role of Dmp1 in Ras-Raf-Arf signaling and cellular senescence. In order to study the interactions of hDMP1 gene product and selected tumor markers with BioMEMS devices, protein coating (Antibody) conduct on cantilevers with silicon nitride (SiNx) surfaces. Silicon nitride surface has the potential to provide a good interface for BioMEMS devices, due to enhanced adherence of substances on this surface. The cantilever biosensors coated with hDMP1 antibody were used for the detection of hDMP1 antigen, which is known to be a tumor suppressor protein. Results revealed that the changes in nano-mechanical forces provided sufficient differential torque to bend the cantilever beam upon injection of the antigen. Theoretical models have been developed for the prediction of the vibrational responses of atomic force microscope (AFM) cantilevers before and after antigen/antibody interaction. Exposure of the proteins to micro-cantilever (MC) resulted in un-reversible large stress. Static deflection of micro-cantilever appeared as a result of the surface stresses that are induced by changes upon antibody-antigen interaction. This indicated that the micro-cantilever approach is useful for detecting proteins and tumor markers, and this system is applicable as a model to design miniaturized biosensor systems. We also applied gene micro-array to identify unknown targets for hDMP1 and extend our observation of the complicated process of carcinogenesis.
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Lillian, Todd D. « An Elastic Rod Representation for the LacI-DNA Loop Complex ». Dans ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-47407.
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The well-recognized Lac repressor protein (LacI) regulates transcription by bending DNA into a loop. In addition to the known role of DNA flexibility, there is accumulating evidence suggesting that the flexibility of LacI also plays a role in this gene regulation. Here we extend our elastic rod model for DNA (previously used to model DNA only) to represent LacI. Specifically, we represent sites of concentrated flexibility in the protein with flexible elastic rod domains; and we represent relatively rigid domains of the protein with stiff elastic rod domains. Our analysis shows the sensitivity of looping energetics to the degree of flexibility within the protein over a large range of DNA lengths. In addition, we show that the predicted energetically dominant binding topology (A) remains upon introducing protein flexibility.
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Islam, Nazmul, Davood Askari et Tarek Trad. « Biocompatible Nanocomposite for Lab-on-a-Chip Application ». Dans ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-64119.
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Lab-on-a-chip (LOC) devices integrate multiple laboratory functions and processes to a miniaturized chip format. Many LOC devices are used in a wide range of biomedical and other analytical applications including rapid pathogen detection, clinical diagnosis, electrophoresis, flow cytometry, and protein and DNA analysis. LOC devices can be fabricated from many types of material including various polymers, glass/silicon, or combinations of these materials. A broad variety of fabrication technologies are used for LOC device fabrication. LOC systems have several common features including microfluidics (e.g. channels, micro-pumps, mixers and valves) and sensing capabilities. This paper describes a technique for the fabrication of a micro-pump that can be used in implantable biocompatible devices. This paper will also discuss the synthesis and properties of biocompatible iron oxide nanoparticles (NPs) for AC electrokinetic micro-pumping. Iron oxide NP will be incorporated with PDMS (polydimithylsiloxane) to obtain biocompatible nanocomposite. The use of photoluminescence, hydrophobic, and reflective optical response of these materials for in-vitro and in-vivo sensing and micro-pumping will be highlighted.
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Woldhuis, R. R., I. H. Heijink, M. Van Den Berge, W. Timens, B. Oliver, M. De Vries et C. Brandsma. « COPD-derived fibroblasts secrete higher levels of senescence associated secretory phenotype (SASP) proteins ». Dans ERS Lung Science Conference 2020 abstracts. European Respiratory Society, 2020. http://dx.doi.org/10.1183/23120541.lsc-2020.28.
Texte intégralRapports d'organisations sur le sujet ""Lhc proteins""
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Nechushtai, Rachel, et Parag Chitnis. Role of the HSP70 Homologue from Chloroplasts in the Assembly of the Photosynthetic Apparatus. United States Department of Agriculture, juillet 1993. http://dx.doi.org/10.32747/1993.7568743.bard.
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The major goal of the proposed research was to study the role of a 70-kDa heat shock cognate protein from chloroplasts (ct-HSP70) in the assembly of chlorophyll-protein complexes. The latters are mostly important in allowing photosynthesis to occur. Photosynthesis is at the heart of crop productivity and the knowledge of the biogenesis of the photosynthetic apparatus is essential to manipulate the efficiency of photosynthesis. The characterization of the function of the ct-HSP70 was planned to be studied in vitro by assaying its capability to physically interact with the thylakoid proteins and to assist their assembly into thylakoid membranes. We planned to identify regions in the light-harvesting complex protein (LHCP) that interact with the ct-HSP70 and characterize the interaction between them. We also intended to isolate cDNA clones encoding ct-HSP70, sequence them, express one of them in E. coli and use the purified protein for functional assays. The research in this BARD proposal aimed at providing insights and aid in understanding the mechanism by which plants may respond to the heat stress. Since plants often experience increased temperatures.
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Fluhr, Robert, et Maor Bar-Peled. Novel Lectin Controls Wound-responses in Arabidopsis. United States Department of Agriculture, janvier 2012. http://dx.doi.org/10.32747/2012.7697123.bard.
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Innate immune responses in animals and plants involve receptors that recognize microbe-associated molecules. In plants, one set of this defense system is characterized by large families of TIR–nucleotide binding site–leucine-rich repeat (TIR-NBS-LRR) resistance genes. The direct interaction between plant proteins harboring the TIR domain with proteins that transmit and facilitate a signaling pathway has yet to be shown. The Arabidopsis genome encodes TIR-domain containing genes that lack NBS and LRR whose functions are unknown. Here we investigated the functional role of such protein, TLW1 (TIR LECTIN WOUNDRESPONSIVE1). The TLW1 gene encodes a protein with two domains: a TIR domain linked to a lectin-containing domain. Our specific aim in this proposal was to examine the ramifications of the TL1-glycan interaction by; A) The functional characterization of TL1 activity in the context of plant wound response and B) Examine the hypothesis that wounding induced specific polysaccharides and examine them as candidates for TL-1 interactive glycan compounds. The Weizmann group showed TLW1 transcripts are rapidly induced by wounding in a JA-independent pathway and T-DNA-tagged tlw1 mutants that lack TLW1 transcripts, fail to initiate the full systemic wound response. Transcriptome methodology analysis was set up and transcriptome analyses indicates a two-fold reduced level of JA-responsive but not JA-independent transcripts. The TIR domain of TLW1 was found to interact directly with the KAT2/PED1 gene product responsible for the final b-oxidation steps in peroxisomal-basedJA biosynthesis. To identify potential binding target(s) of TL1 in plant wound response, the CCRC group first expressed recombinant TL1 in bacterial cells and optimized conditions for the protein expression. TL1 was most highly expressed in ArcticExpress cell line. Different types of extraction buffers and extraction methods were used to prepare plant extracts for TL1 binding assay. Optimized condition for glycan labeling was determined, and 2-aminobenzamide was used to label plant extracts. Sensitivity of MALDI and LC-MS using standard glycans. THAP (2,4,6- Trihydroxyacetophenone) showed minimal background peaks at positive mode of MALDI, however, it was insensitive with a minimum detection level of 100 ng. Using LC-MS, sensitivity was highly increased enough to detect 30 pmol concentration. However, patterns of total glycans displayed no significant difference between different extraction conditions when samples were separated with Dionex ICS-2000 ion chromatography system. Transgenic plants over-expressing lectin domains were generated to obtain active lectin domain in plant cells. Insertion of the overexpression construct into the plant genome was confirmed by antibiotic selection and genomic DNA PCR. However, RT-PCR analysis was not able to detect increased level of the transcripts. Binding ability of azelaic acid to recombinant TL1. Azelaic acid was detected in GST-TL1 elution fraction, however, DHB matrix has the same mass in background signals, which needs to be further tested on other matrices. The major findings showed the importance of TLW1 in regulating wound response. The findings demonstrate completely novel and unexpected TIR domain interactions and reveal a control nexus and mechanism that contributes to the propagation of wound responses in Arabidopsis. The implications are to our understanding of the function of TIR domains and to the notion that early molecular events occur systemically within minutes of a plant sustaining a wound. A WEB site (http://genome.weizmann.ac.il/hormonometer/) was set up that enables scientists to interact with a collated plant hormone database.
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Tucker, Mark L., Shimon Meir, Amnon Lers, Sonia Philosoph-Hadas et Cai-Zhong Jiang. Elucidation of signaling pathways that regulate ethylene-induced leaf and flower abscission of agriculturally important plants. United States Department of Agriculture, janvier 2012. http://dx.doi.org/10.32747/2012.7597929.bard.
Texte intégralRésumé :
The Problem: Abscission is a highly regulated process, occurring as a natural terminal stage of development, in which various organs are separated from the parent plant. In most plant species, the process is initiated by a decrease in active auxin in the abscission zone (AZ) and an increase in ethylene, and may be accelerated by postharvest or environmental stresses. Another potential key regulator in abscission is IDA (Inflorescence Deficient in Abscission), which was identified as an essential peptide signal for floral organ abscission in Arabidopsis. However, information is still lacking regarding the molecular mechanisms integrating all these regulators. In our previous BARD funded research we made substantial progress towards understanding these molecular events in tomato, and the study is still in progress. We established a powerful platform for analysis of genes for regulatory proteins expressed in AZ. We identified changes in gene expression for several transcription factors (TFs) directly linked to ethylene and auxin signaling and several additional regulatory proteins not so obviously linked to these hormones. Moreover, we demonstrated using a virus-induced gene silencing (VIGS) assay that several play a functional role in the onset of abscission. Based on these results we have selected 14 genes for further analysis in stably transformed tomato plants. All 14 genes were suppressed by RNA interference (RNAi) using a constitutive promoter, and 5 of them were also suppressed using an abscission-specific promoter. Transformations are currently at different stages of progress including some lines that already display an abscission phenotype. Objectives: We propose here to (1) complete the functional analysis of the stably transformed tomato plants with T2 lines and perform transcriptome analysis using custom abscission-specific microarrays; (2) conduct an indepth analysis of the role of IDA signaling in tomato leaf and flower abscission; (3) perform transcriptome and proteome analyses to extend the earlier gene expression studies to identify transcripts and proteins that are highly specific to the separation layer (i.e., target cells for cell separation) prior to the onset of abscission; (4) extend and compliment the work in tomato using a winnowed set of genes in soybean. Methodology: Next Generation Sequencing (NGS) of mRNA will be used to further increase the list of abscission-associated genes, and for preparation of a custom tomato abscission microarray to test altered gene expression in transgenic plants. Tandem mass spectrometry (LC-MS/MS) of protein extracts from leaf petiole, flower pedicel and their AZ tissues will be used to identify the proteome of the AZ before and during abscission. AZ-specific gene promoters will be used in stably transformed tomato plants to reduce non-target phenotypes. The bean pod mottle virus (BPMV) plasmid vectors will be used for VIGS analysis in soybean. Expected Contribution: Our study will provide new insights into the regulation of ethylene-induced abscission by further revealing the role of key regulators in the process. This will permit development of novel techniques for manipulating leaf and flower abscission, thereby improving the postharvest performance of agriculturally important crops.
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Blumwald, Eduardo, et Avi Sadka. Sugar and Acid Homeostasis in Citrus Fruit. United States Department of Agriculture, janvier 2012. http://dx.doi.org/10.32747/2012.7697109.bard.
Texte intégralRésumé :
Citrus fruit quality standards have been determined empirically, depending on species and on the particular growing regions. In general, the TSS (total soluble solids) to total acidity (TA) ratio determines whether citrus fruit can be marketed. Soluble sugars account for most of the TSS during harvest while TA is determined almost solely by the citric acid content, which reaches levels of 1-5% by weight in many cultivated varieties. Acid and sugar homeostasis in the fruit is critical for the management of existing cultivars, the development of new cultivars, the improvement of pre- and post-harvest strategies and the control of fruit quality and disorders. The current proposal (a continuation of a previous proposal) aimed at: (1) completing the citrus fruit proteome and metabolome, and establish a citrus fruit functional database, (2) further characterization of the control of fruit acidity by studying the regulation of key steps affecting citrate metabolism, and determine the fate of citrate during acid decline stage, and (3) Studying acid and sugar homeostasis in citrus fruits by characterizing transport mechanisms across membranes. These aims were completed as the following: (1) Our initial efforts were aimed at the characterization and identification of citric acid transporters in citrus juice cells. The identification of citrate transporters at the vacuole of the citrus juice cell indicated that the steady-state citrate cytosolic concentration and the action of the cytosolic aconitase were key elements in establishing the pH homeostat in the cell that regulates the metabolic shift towards carbon usage in the fruit during the later stages of fruit development. We focused on the action of aconitase, the enzyme mediating the metabolic use of citric acid in the cells, and identified processes that control carbon fluxes in developing citrus fruits that control the fruit acid load; (2) The regulation of aconitase, catalyzing a key step in citrate metabolism, was further characterized by using two inhibitors, citramalte and oxalomalte. These compounds significantly increased citrate content and reduced the enzyme’s activity. Metabolite profiling and changes of amino-acid metabolizing enzymes in oxalomalate- treated cells suggested that the increase in citrate, caused by aconitase inhibition, induces amino acid synthesis and the GABA shunt, in accordance with the suggested fate of citrate during the acid decline stage in citrus fruit. (3) We have placed a considerable amount of time on the development of a citrus fruit proteome that will serve to identify all of the proteins in the juice cells and will also serve as an aid to the genomics efforts of the citrus research community (validating the annotation of the fruit genes and the different ESTs). Initially, we identified more than 2,500 specific fruit proteins and were able to assign a function to more than 2,100 proteins (Katz et al., 2007). We have now developed a novel Differential Quantitative LC-MS/MS Proteomics Methodology for the identification and quantitation of key biochemical pathways in fruits (Katz et al., 2010) and applied this methodology to identify determinants of key traits for fruit quality (Katz et al., 2011). We built “biosynthesis maps” that will aid in defining key pathways associated with the development of key fruit quality traits. In addition, we constructed iCitrus (http://wiki.bioinformatics.ucdavis.edu/index.php/ICitrus), a “functional database” that is essentially a web interface to a look-up table that allows users to use functional annotations in the web to identify poorly annotated citrus proteins. This resource will serve as a tool for growers and field extension specialists.
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Heifetz, Yael, et Michael Bender. Success and failure in insect fertilization and reproduction - the role of the female accessory glands. United States Department of Agriculture, décembre 2006. http://dx.doi.org/10.32747/2006.7695586.bard.
Texte intégralRésumé :
The research problem. Understanding of insect reproduction has been critical to the design of insect pest control strategies including disruptions of mate-finding, courtship and sperm transfer by male insects. It is well known that males transfer proteins to females during mating that profoundly affect female reproductive physiology, but little is known about the molecular basis of female mating response and no attempts have yet been made to interfere with female post-mating responses that directly bear on the efficacy of fertilization. The female reproductive tract provides a crucial environment for the events of fertilization yet thus far those events and the role of the female tract in influencing them are poorly understood. For this project, we have chosen to focus on the lower reproductive tract because it is the site of two processes critical to reproduction: sperm management (storage, maintenance, and release from storage) and fertilization. E,fforts during this project period centered on the elucidation of mating responses in the female lower reproductive tract The central goals of this project were: 1. To identify mating-responsive genes in the female lower reproductive tract using DNA microarray technology. 2. In parallel, to identify mating-responsive genes in these tissues using proteomic assays (2D gels and LC-MS/MS techniques). 3. To integrate proteomic and genomic analyses of reproductive tract gene expression to identify significant genes for functional analysis. Our main achievements were: 1. Identification of mating-responsive genes in the female lower reproductive tract. We identified 539 mating-responsive genes using genomic and proteomic approaches. This analysis revealed a shift from gene silencing to gene activation soon after mating and a peak in differential gene expression at 6 hours post-mating. In addition, comparison of the two datasets revealed an expression pattern consistent with the model that important reproductive proteins are pre-programmed for synthesis prior to mating. This work was published in Mack et al. (2006). Validation experiments using real-time PCR techniques suggest that microarray assays provide a conservativestimate of the true transcriptional activity in reproductive tissues. 2.lntegration of proteomics and genomics data sets. We compared the expression profiles from DNA microarray data with the proteins identified in our proteomic experiments. Although comparing the two data sets poses analyical challenges, it provides a more complete view of gene expression as well as insights into how specific genes may be regulated. This work was published in Mack et al. (2006). 3. Development of primary reproductive tract cell cultures. We developed primary cell cultures of dispersed reproductive tract cell types and determined conditions for organ culture of the entire reproductive tract. This work will allow us to rapidly screen mating-responsive genes for a variety of reproductive-tract specifi c functions. Scientific and agricultural significance. Together, these studies have defined the genetic response to mating in a part of the female reproductive tract that is critical for successful fertllization and have identified alarge set of mating-responsive genes. This work is the first to combine both genomic and proteomic approaches in determining female mating response in these tissues and has provided important insights into insect reproductive behavior.
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Meidan, Rina, et Robert Milvae. Regulation of Bovine Corpus Luteum Function. United States Department of Agriculture, mars 1995. http://dx.doi.org/10.32747/1995.7604935.bard.
Texte intégralRésumé :
The main goal of this research plan was to elucidate regulatory mechanisms controlling the development, function of the bovine corpus luteum (CL). The CL contains two different sterodigenic cell types and therefore it was necessary to obtain pure cell population. A system was developed in which granulosa and theca interna cells, isolated from a preovulatory follicle, acquired characteristics typical of large (LL) and small (SL) luteal cells, respectively, as judged by several biochemical and morphological criteria. Experiments were conducted to determine the effects of granulosa cells removal on subsequent CL function, the results obtained support the concept that granulosa cells make a substaintial contribution to the output of progesterone by the cyclic CL but may have a limited role in determining the functional lifespan of the CL. This experimental model was also used to better understand the contribution of follicular granulosa cells to subsequent luteal SCC mRNA expression. The mitochondrial cytochrome side-chain cleavage enzyme (SCC), which converts cholesterol to pregnenolone, is the first and rate-limiting enzyme of the steroidogenic pathway. Experiments were conducted to characterize the gene expression of P450scc in bovine CL. Levels of P450scc mRNA were higher during mid-luteal phase than in either the early or late luteal phases. PGF 2a injection decreased luteal P450scc mRNA in a time-dependent manner; levels were significantly reduced by 2h after treatment. CLs obtained from heifers on day 8 of the estrous cycle which had granulosa cells removed had a 45% reduction in the levels of mRNA for SCC enzymes as well as a 78% reduction in the numbers of LL cells. To characterize SCC expression in each steroidogenic cell type we utilized pure cell populations. Upon luteinization, LL expressed 2-3 fold higher amounts of both SCC enzymes mRNAs than SL. Moreover, eight days after stimulant removal, LL retained their P4 production capacity, expressed P450scc mRNA and contained this protein. In our attempts to establish the in vitro luteinization model, we had to select the prevulatory and pre-gonadotropin surge follicles. The ratio of estradiol:P4 which is often used was unreliable since P4 levels are high in atretic follicles and also in preovulatory post-gonadotropin follicles. We have therefore examined whether oxytocin (OT) levels in follicular fluids could enhance our ability to correctly and easily define follicular status. Based on E2 and OT concentrations in follicular fluids we could more accurately identify follicles that are preovulatory and post gonadotropin surge. Next we studied OT biosynthesis in granulosa cells, cells which were incubated with forskolin contained stores of the precursor indicating that forskolin (which mimics gonadotropin action) is an effective stimulator of OT biosynthesis and release. While studying in vitro luteinization, we noticed that IGF-I induced effects were not identical to those induced by insulin despite the fact that megadoses of insulin were used. This was the first indication that the cells may secrete IGF binding protein(s) which regonize IGFs and not insulin. In a detailed study involving several techniques, we characterized the species of IGF binding proteins secreted by luteal cells. The effects of exogenous polyunsaturated fatty acids and arachidonic acid on the production of P4 and prostanoids by dispersed bovine luteal cells was examined. The addition of eicosapentaenoic acid and arachidonic acid resulted in a dose-dependent reduction in basal and LH-stimulated biosynthesis of P4 and PGI2 and an increase in production of PGF 2a and 5-HETE production. Indomethacin, an inhibitor of arachidonic acid metabolism via the production of 5-HETE was unaffected. Results of these experiments suggest that the inhibitory effect of arachidonic acid on the biosynthesis of luteal P4 is due to either a direct action of arachidonic acid, or its conversion to 5-HETE via the lipoxgenase pathway of metabolism. The detailed and important information gained by the two labs elucidated the mode of action of factors crucially important to the function of the bovine CL. The data indicate that follicular granulosa cells make a major contribution to numbers of large luteal cells, OT and basal P4 production, as well as the content of cytochrome P450 scc. Granulosa-derived large luteal cells have distinct features: when luteinized, the cell no longer possesses LH receptors, its cAMP response is diminished yet P4 synthesis is sustained. This may imply that maintenance of P4 (even in the absence of a Luteotropic signal) during critical periods such as pregnancy recognition, is dependent on the proper luteinization and function of the large luteal cell.
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Brown Horowitz, Sigal, Eric L. Davis et Axel Elling. Dissecting interactions between root-knot nematode effectors and lipid signaling involved in plant defense. United States Department of Agriculture, janvier 2014. http://dx.doi.org/10.32747/2014.7598167.bard.
Texte intégralRésumé :
Root-knot nematodes, Meloidogynespp., are extremely destructive pathogens with a cosmopolitan distribution and a host range that affects most crops. Safety and environmental concerns related to the toxicity of nematicides along with a lack of natural resistance sources threaten most crops in Israel and the U.S. This emphasizes the need to identify genes and signal mechanisms that could provide novel nematode control tactics and resistance breeding targets. The sedentary root-knot nematode (RKN) Meloidogynespp. secrete effectors in a spatial and temporal manner to interfere with and mimic multiple physiological and morphological mechanisms, leading to modifications and reprogramming of the host cells' functions, resulted in construction and maintenance of nematodes' feeding sites. For successful parasitism, many effectors act as immunomodulators, aimed to manipulate and suppress immune defense signaling triggered upon nematode invasion. Plant development and defense rely mainly on hormone regulation. Herein, a metabolomic profiling of oxylipins and hormones composition of tomato roots were performed using LC-MS/MS, indicating a fluctuation in oxylipins profile in a compatible interaction. Moreover, further attention was given to uncover the implication of WRKYs transcription factors in regulating nematode development. In addition, in order to identify genes that might interact with the lipidomic defense pathway induced by oxylipins, a RNAseq was performed by exposing M. javanicasecond-stage juveniles to tomato protoplast, 9-HOT and 13-KOD oxylipins. This transcriptome generated a total of 4682 differentially expressed genes (DEGs). Being interested in effectors, we seek for DEGs carrying a predicted secretion signal peptide. Among the DEGs including signal peptide, several had homology with known effectors in other nematode species, other unknown potentially secreted proteins may have a role as root-knot nematodes' effectors which might interact with lipid signaling. The molecular interaction of LOX proteins with the Cyst nematode effectors illustrate the nematode strategy in manipulating plant lipid signals. The function of several other effectors in manipulating plant defense signals, as well as lipids signals, weakening cell walls, attenuating feeding site function and development are still being studied in depth for several novel effectors. As direct outcome of this project, the accumulating findings will be utilized to improve our understanding of the mechanisms governing critical life-cycle phases of the parasitic M. incognita RKN, thereby facilitating design of effective controls based on perturbation of nematode behavior—without producing harmful side effects. The knowledge from this study will promote genome editing strategies aimed at developing nematode resistance in tomato and other nematode-susceptible crop species in Israel and the United States.
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Bercovier, Herve, et Ronald P. Hedrick. Diagnostic, eco-epidemiology and control of KHV, a new viral pathogen of koi and common carp. United States Department of Agriculture, décembre 2007. http://dx.doi.org/10.32747/2007.7695593.bard.
Texte intégralRésumé :
Original objectives and revisions-The proposed research included these original objectives: field validation of diagnostic tests (PCR), the development and evaluation of new sensitive tools (LC-PCR/TaqManPCR, antibody detection by ELISA) including their use to study the ecology and the epidemiology of KHV (virus distribution in the environment and native cyprinids) and the carrier status of fish exposed experimentally or naturally to KHV (sites of virus replication and potential persistence or latency). In the course of the study we completed the genome sequence of KHV and developed a DNA array to study the expression of KHV genes in different conditions. Background to the topics-Mass mortality of koi or common carp has been observed in Israel, USA, Europe and Asia. These outbreaks have reduced exports of koi from Israel and have created fear about production, import, and movements of koi and have raised concerns about potential impacts on native cyprinid populations in the U.S.A. Major conclusions-A suite of new diagnostic tools was developed that included 3 PCR assays for detection of KHV DNA in cell culture and fish tissues and an ELISA assay capable of detecting anti-KHV antibodies in the serum of koi and common carp. The TKPCR assay developed during the grant has become an internationally accepted gold standard for detection of viral DNA. Additionally, the ELISA developed for detecting serum anti-KHV antibodies is now in wide use as a major nonlethal screening tool for evaluating virus status of koi and common carp populations. Real time PCR assays have been able to detect viral DNA in the internal organs of survivors of natural and wild type vaccine exposures at 1 and 10³ genome equivalents at 7 months after exposure. In addition, vaccinated fish were able to transmit the virus to naive fish. Potential control utilizing hybrids of goldfish and common carp for production demonstrated they were considerably more resistant than pure common carp or koi to both KHV (CyHV-3). There was no evidence that goldfish or other tested endemic cyprinids species were susceptible to KHV. The complete genomic sequencing of 3 strains from Japan, the USA, and Israel revealed a 295 kbp genome containing a 22 kbp terminal direct repeat encoding clear gene homologs to other fish herpesviruses in the family Herpesviridae. The genome encodes156 unique protein-coding genes, eight of which are duplicated in the terminal repeat. Four to seven genes are fragmented and the loss of these genes may be associated with the high virulence of the virus. Viral gene expression was studies by a newly developed chip which has allowed verification of transcription of most all hypothetical genes (ORFs) as well as their kinetics. Implications, both scientific and agricultural- The results from this study have immediate application for the control and management of KHV. The proposal provides elements key to disease management with improved diagnostic tools. Studies on the ecology of the virus also provide insights into management of the virus at the farms that farmers will be able to apply immediately to reduce risks of infections. Lastly, critical issues that surround present procedures used to create “resistant fish” must be be resolved (e.g. carriers, risks, etc.). Currently stamping out may be effective in eradicating the disease. The emerging disease caused by KHV continues to spread. With the economic importance of koi and carp and the vast international movements of koi for the hobby, this disease has the potential for even further spread. The results from our studies form a critical component of a comprehensive program to curtail this emerging pathogen at the local, regional and international levels.