Academic literature on the topic 'Stress response protein p66ShcA'
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Journal articles on the topic "Stress response protein p66ShcA"
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Hu, Yuanyu, Xueying Wang, Li Zeng, De-Yu Cai, Kanaga Sabapathy, Stephen P. Goff, Eduardo J. Firpo, and Baojie Li. "ERK Phosphorylates p66shcA on Ser36 and Subsequently Regulates p27kip1 Expression via the Akt-FOXO3a Pathway: Implication of p27kip1 in Cell Response to Oxidative Stress." Molecular Biology of the Cell 16, no. 8 (August 2005): 3705–18. http://dx.doi.org/10.1091/mbc.e05-04-0301.
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Mice deficient for p66shcA represent an animal model to link oxidative stress and aging. p66shcA is implicated in oxidative stress response and mitogenic signaling. Phosphorylation of p66shcA on Ser36 is critical for its function in oxidative stress response. Here we report the identification of ERK as the kinase phosphorylating p66shcA on Ser36. Activation of ERKs was necessary and sufficient for Ser36 phosphorylation. p66shcA interacted with ERK and was demonstrated to be a substrate for ERK, with Ser36 being the major phosphorylation site. Furthermore, in response to H2O2, inhibition of ERK activation repressed p66shcA-dependent phosphorylation of FOXO3a and the down-regulation of its target gene p27kip1. Down-regulation of p27 might promote cell survival, as p27 played a proapoptotic role in oxidative stress response. As a feedback regulation, Ser36 phosphorylated p66shcA attenuated H2O2-induced ERK activation, whereas p52/46shcA facilitated ERK activation, which required tyrosine phosphorylation of CH1 domain. p66shcA formed a complex with p52/46ShcA, which may provide a platform for efficient signal propagation. Taken together, the data suggest there exists an interplay between ERK and ShcA proteins, which modulates the expression of p27 and cell response to oxidative stress.
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Husain, Mohammad, Leonard G. Meggs, Himanshu Vashistha, Sonia Simoes, Kevin O. Griffiths, Dileep Kumar, Joanna Mikulak, et al. "Inhibition of p66ShcA Longevity Gene Rescues Podocytes from HIV-1-induced Oxidative Stress and Apoptosis." Journal of Biological Chemistry 284, no. 24 (April 21, 2009): 16648–58. http://dx.doi.org/10.1074/jbc.m109.008482.
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Glomerular visceral epithelial cells (podocytes) play a critical role in the pathogenesis of human immunodeficiency virus (HIV)-associated nephropathy. A key question concerns the mechanism(s) by which the HIV-1 genome alters the phenotype of the highly specialized, terminally differentiated podocytes. Here, using an in vitro system of conditionally immortalized differentiated human podocytes (CIDHPs), we document a pivotal role for the p66ShcA protein in HIV-1-induced reactive oxygen species generation and CIDHP apoptosis. CIDHP transfected with truncated HIV-1 construct (NL4-3) exhibit increased reactive oxygen species metabolism, DNA strand breaks, and a 5-fold increase in apoptosis, whereas the opposite was true for NL4-3/CIDHP co-transfected with mu-36p66ShcA (mu-36) dominant negative expression vector or isoform-specific p66-small interfering RNA. Phosphorylation at Ser-36 of the wild type p66ShcA protein, required for p66ShcA redox function and inhibition of the potent stress response regulator Foxo3a, was unchanged in mu-36/NL4-3/CIDHP but increased in NL4-3/CIDHP. Acute knockdown of Foxo3a by small interfering RNA induced a 50% increase in mu-36/NL4-3/CIDHP apoptosis, indicating that Foxo3a-dependent responses promote the survival phenotype in mu-36 cells. We conclude that inhibition of p66ShcA redox activity prevents generation of HIV-1 stress signals and activation of the CIDHP apoptosis program.
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Canedo, Eduardo Cepeda, Sonia Del Rincon, Peter Siegel, Michael Witcher, and Josie Ursini-Siegel. "Abstract 131: The role of p66ShcA in the melanoma oncogenesis process." Cancer Research 82, no. 12_Supplement (June 15, 2022): 131. http://dx.doi.org/10.1158/1538-7445.am2022-131.
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Abstract Background: The identification of crucial driver mutations that affect the MAPK signaling pathway (BRAF, NRAS, NF1) in melanomas, has allowed for the development of targeted therapies and shed light on the process of melanocyte transformation. Gain of function mutations in proteins within the Ras/MAPK pathway in melanocytes leads to the formation of benign neoplasms, or nevi. Multiple mechanisms prevent the transformation of nevi into invasive cancer, namely, oncogene-induced senescence (OIS) and immunosurveillance. Of interest to the melanomagenesis process is the p66ShcA redox protein. We have found that compared to other solid cancers, the majority of primary human melanomas, patient-derived xenografts and melanoma cell lines strongly overexpress p66ShcA, an adaptor protein that induces production of reactive oxygen species (ROS) in response to stress stimuli. Indeed, UV light, increases p66ShcA levels and p66ShcA-induced oxidative stress, which is relevant to this disease as sun exposure contributes significantly to melanoma development. We hypothesized that p66ShcA may play a crucial role in the early steps of melanocyte transformation, possibly by contributing to the overriding of OIS and immune surveillance. Methods: Melanoma initiation and progression will be examined in a known transgenic mouse model (Tyr::CRE/brafCA/ptenlox/lox) either in the presence of endogenous levels of p66ShcA or in an inducible p66ShcA over-expression setting. The necessity of p66ShcA-high expression for melanocyte BRAFV600E-transformation will be tested in immortalized melanocytes. Lastly, to explore the potential selection advantage conferred by p66ShcA, its expression will be silenced in a panel of known melanoma cell lines. Clonogenic assays as well as mouse xenografts will be performed. Results: TCGA melanoma datasets, immunoblot analysis of human melanoma cell lines (n>10), and a collection of metastatic patient-derived xenografts (PDX) (n=6) indicate uniformly elevated p66ShcA levels compared to other cancer types. Knock-down of p66ShcA in multiple melanoma cell lines reduces their clonogenic potential. This reduction in colony formation is independent of driver mutation (e.g., BRAF, NRAS, NF1). Suggesting that p66ShcA may sustain melanoma proliferation. Furthermore, xenografts of the murine YUMM1.7 cell line (braf mutant, cdkn2a null and pten null) in immune-deficient and immune-competent mice indicate that loss of p66ShcA (YUMM1.7 p66ShcA-KO) delays tumor formation, specifically in mice with an intact immune system. Citation Format: Eduardo Cepeda Canedo, Sonia Del Rincon, Peter Siegel, Michael Witcher, Josie Ursini-Siegel. The role of p66ShcA in the melanoma oncogenesis process [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 131.
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Malhotra, Ashwani, Himanshu Vashistha, Virendra S. Yadav, Michael G. Dube, Satya P. Kalra, Maha Abdellatif, and Leonard G. Meggs. "Inhibition of p66ShcA redox activity in cardiac muscle cells attenuates hyperglycemia-induced oxidative stress and apoptosis." American Journal of Physiology-Heart and Circulatory Physiology 296, no. 2 (February 2009): H380—H388. http://dx.doi.org/10.1152/ajpheart.00225.2008.
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Apoptotic myocyte cell death, diastolic dysfunction, and progressive deterioration in left ventricular pump function characterize the clinical course of diabetic cardiomyopathy. A key question concerns the mechanism(s) by which hyperglycemia (HG) transmits danger signals in cardiac muscle cells. The growth factor adapter protein p66ShcA is a genetic determinant of longevity, which controls mitochondrial metabolism and cellular responses to oxidative stress. Here we demonstrate that interventions which attenuate or prevent HG-induced phosphorylation at critical position 36 Ser residue (phospho-Ser36) inhibit the redox function of p66ShcA and promote the survival phenotype. Adult rat ventricular myocytes obtained by enzymatic dissociation were transduced with mutant-36 p66ShcA (mu-36) dominant-negative expression vector and plated in serum-free media containing 5 or 25 mM glucose. At HG, adult rat ventricular myocytes exhibit a marked increase in reactive oxygen species production, upregulation of phospho-Ser36, collapse of mitochondrial transmembrane potential, and increased formation of p66ShcA/cytochrome- c complexes. These indexes of oxidative stress were accompanied by a 40% increase in apoptosis and the upregulation of cleaved caspase-3 and the apoptosis-related proteins p53 and Bax. To test whether p66ShcA functions as a redox-sensitive molecular switch in vivo, we examined the hearts of male Akita diabetic nonobese (C57BL/6J) mice. Western blot analysis detected the upregulation of phospho-Ser36, the translocation of p66ShcA to mitochondria, and the formation of p66ShcA/cytochrome- c complexes. Conversely, the correction of HG by recombinant adeno-associated viral delivery of leptin reversed these alterations. We conclude that p66ShcA is a molecular switch whose redox function is turned on by phospho-Ser36 and turned off by interventions that prevent this modification.
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Vashistha, H., L. Marrero, K. Reiss, A. J. Cohen, A. Malhotra, T. Javed, A. Bradley, et al. "Aging phenotype(s) in kidneys of diabetic mice are p66ShcA dependent." American Journal of Physiology-Renal Physiology 315, no. 6 (December 1, 2018): F1833—F1842. http://dx.doi.org/10.1152/ajprenal.00608.2017.
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The p66ShcA protein controls cellular responses to oxidative stress, senescence, and apoptosis. Here, we test the hypothesis that aging phenotype(s) commonly associated with the broad category of chronic kidney disease are accelerated in diabetic kidneys and linked to the p66ShcA locus. At the organ level, tissue stem cells antagonize senescent phenotypes by replacing old dysfunctional cells. Using established methods, we isolated a highly purified population of stem cell antigen-1-positive mesenchymal stem cells (Sca-1+ MSCs) from kidneys of wild-type (WT) and p66 knockout (p66 KO) mice. Cells were plated in culture medium containing normal glucose (NG) or high glucose (HG). Reactive oxygen species (ROS) metabolism was substantially increased in WT MSCs in HG medium in association with increased cell death by apoptosis and acquisition of the senescent phenotype. DNA microarray analysis detected striking differences in the expression profiles of WT and p66 KO-MSCs in HG medium. Unexpectedly, the analysis for p66 KO-MSCs revealed upregulation of Wnt genes implicated in self-renewal and differentiation. To test the in vivo consequences of constitutive p66 expression in diabetic kidneys, we crossed the Akita diabetic mouse with the p66KO mouse. Homozygous mutation at the p66 locus delays or prevents aging phenotype(s) in the kidney that may be precursors to diabetic nephropathy.
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Miyazawa, Masaki, and Yoshiaki Tsuji. "Evidence for a novel antioxidant function and isoform-specific regulation of the human p66Shc gene." Molecular Biology of the Cell 25, no. 13 (July 2014): 2116–27. http://dx.doi.org/10.1091/mbc.e13-11-0666.
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The mammalian Shc family, composed of p46, p52, and p66 isoforms, serves as an adaptor protein in cell growth and stress response. p66Shc was shown to be a negative lifespan regulator by acting as a prooxidant protein in mitochondria; however, the regulatory mechanisms of p66Shc expression and function are incompletely understood. This study provides evidence for new features of p66Shc serving as an antioxidant and critical protein in cell differentiation. Unique among the Shc family, transcription of p66Shc is activated through the antioxidant response element (ARE)–nuclear factor erythroid 2–related factor 2 (Nrf2) pathway in K562 human erythroleukemia and other cell types after treatment with hemin, an iron-containing porphyrin. Phosphorylated p66Shc at Ser-36, previously reported to be prone to mitochondrial localization, is increased by hemin treatment, but p66Shc remains exclusively in the cytoplasm. p66Shc knockdown inhibits hemin-induced erythroid differentiation, in which reactive oxygen species production and apoptosis are significantly enhanced in conjunction with suppression of other ARE-dependent antioxidant genes. Conversely, p66Shc overexpression is sufficient for inducing erythroid differentiation. Collectively these results demonstrate the isoform-specific regulation of the Shc gene by the Nrf2-ARE pathway and a new antioxidant role of p66Shc in the cytoplasm. Thus p66Shc is a bifunctional protein involved in cellular oxidative stress response and differentiation.
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Betts, Dean H., Nathan T. Bain, and Pavneesh Madan. "The p66Shc Adaptor Protein Controls Oxidative Stress Response in Early Bovine Embryos." PLoS ONE 9, no. 1 (January 24, 2014): e86978. http://dx.doi.org/10.1371/journal.pone.0086978.
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Pacini, Sonia, Michela Pellegrini, Enrica Migliaccio, Laura Patrussi, Cristina Ulivieri, Andrea Ventura, Fabio Carraro, et al. "p66SHC Promotes Apoptosis and Antagonizes Mitogenic Signaling in T Cells." Molecular and Cellular Biology 24, no. 4 (February 15, 2004): 1747–57. http://dx.doi.org/10.1128/mcb.24.4.1747-1757.2004.
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ABSTRACT Of the three Shc isoforms, p66Shc is responsible for fine-tuning p52/p46Shc signaling to Ras and has been implicated in apoptotic responses to oxidative stress. Here we show that human peripheral blood lymphocytes and mouse thymocytes and splenic T cells acquire the capacity to express p66Shc in response to apoptogenic stimulation. Using a panel of T-cell transfectants and p66Shc−/− T cells, we show that p66Shc expression results in increased susceptibility to apoptogenic stimuli, which depends on Ser36 phosphorylation and correlates with an altered balance in apoptosis-regulating gene expression. Furthermore, p66Shc blunts mitogenic responses to T-cell receptor engagement, at least in part by transdominant inhibition of p52Shc signaling to Ras/mitogen-activated protein kinases, in an S36-dependent manner. The data highlight a novel interplay between p66Shc and p52Shc in the control of T-cell fate.
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Migliaccio, Enrica, Marco Giorgio, Simonetta Mele, Giuliana Pelicci, Paolo Reboldi, Pier Paolo Pandolfi, Luisa Lanfrancone, and Pier Giuseppe Pelicci. "The p66shc adaptor protein controls oxidative stress response and life span in mammals." Nature 402, no. 6759 (November 1999): 309–13. http://dx.doi.org/10.1038/46311.
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Sun, Lin, Li Xiao, Jing Nie, Fu-you Liu, Guang-hui Ling, Xue-jing Zhu, Wen-bin Tang, et al. "p66Shc mediates high-glucose and angiotensin II-induced oxidative stress renal tubular injury via mitochondrial-dependent apoptotic pathway." American Journal of Physiology-Renal Physiology 299, no. 5 (November 2010): F1014—F1025. http://dx.doi.org/10.1152/ajprenal.00414.2010.
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p66Shc, a promoter of apoptosis, modulates oxidative stress response and cellular survival, but its role in the progression of diabetic nephropathy is relatively unknown. In this study, mechanisms by which p66Shc modulates high-glucose (HG)- or angiotensin (ANG) II-induced mitochondrial dysfunction were investigated in renal proximal tubular cells (HK-2 cells). Expression of p66Shc and its phosphorylated form (p-p66Shc, serine residue 36) and apoptosis were notably increased in renal tubules of diabetic mice, suggesting an increased reactive oxygen species production. In vitro, HG and ANG II led to an increased expression of total and p-p66Shc in HK-2 cells. These changes were accompanied with increased production of mitochondrial H2O2, reduced mitochondrial membrane potential, increased translocation of mitochondrial cytochrome c from mitochondria into cytosol, upregulation of the expression of caspase-9, and ultimately reduced cell survival. Overexpression of a dominant-negative Ser36 mutant p66Shc (p66ShcS36A) or treatment of p66Shc- or PKC-β-short interfering RNAs partially reversed these changes. Treatment of HK-2 cells with HG and ANG II also increased the protein-protein association between p-p66Shc and Pin1, an isomerase, in the cytosol, and with cytochrome c in the mitochondria. These interactions were partially disrupted with the treatment of PKC-β inhibitor or Pin1-short interfering RNA. These data suggest that p66Shc mediates HG- and ANG II-induced mitochondrial dysfunctions via PKC-β and Pin1-dependent pathways in renal tubular cells.
Dissertations / Theses on the topic "Stress response protein p66ShcA"
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Covington, Sean M. "The Stress Protein Response of Pimephales promelas to Copper." Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc500868/.
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Organisms synthesize stress proteins in response to a variety of stressors. The 68/70-kDa proteins (synonymous to the 72/73-kDa proteins) have shown to be the most promising stress proteins, and have been proposed as a biomarker of general organismal stress. The 68/70-kDa proteins were used in an antigen/antibody based approach to determine the duration of the stress protein response of Pimephales promelas following an acute exposure to copper sulphate.
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Gonçalves, Nuno M. "Insights into the rice response to abiotic stress:." Doctoral thesis, Universidade Nova de Lisboa, Instituto de Tecnologia Química e Biológica António Xavier, 2019. http://hdl.handle.net/10362/95814.
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"Abiotic stress is one of the biggest threats to food security
worldwide, enhanced by a changing global climate and the alarming
gap in crop productivity to face population growth. Rice (Oryza sativa)
is one of the top staple food crops worldwide, along with wheat and
maize, and is also one of the most susceptible monocots to abiotic
stress, such as salinity, with moderate stress leading to up to 90%
production losses."N/A
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Fogl, Claudia Liliane Fiona. "Structure and function of the cardiac stress response protein MS1." Thesis, University of Leicester, 2011. http://hdl.handle.net/2381/9408.
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Myocyte Stress 1 (ms1)/Striated muscle Activator of Rho Signalling (STARS), also known as Actin Binding Rho Activator (ABRA), is a 375 amino acid protein. Its expression increases one hour after the induction of stress in rat hearts through aortic banding. This expression precedes that of early response genes such as c-fos and c-jun. This process has been implicated in the development of left ventricular hypertrophy. ms1/STARS binds to actin, and deletion mutations had shown that residues 234-375 were necessary for actin binding. A mixture of combinatorial domain hunting and rational domain design gave a series of possible domains. Circular dichroism and nuclear magnetic resonance spectroscopy were used to characterise these domains. The first three domains, MSD1 (residues 2-118), MSD2 (40-196) and actin binding domain 1 (ABD1, 193-296) were unfolded, while ABD2 (294-375) was folded. Actin co-sedimentation assays showed that only ABD1 and ABD2 bound to actin. They bound to actin independently. The structure of ABD2 was determined using NMR. Mutation studies, based on the NMR structure and on data about the conservation of positively-charged regions in ms1/STARS homologues, were used to identify the actin binding surface of ABD2. The structure of ABD2 was shown to be a winged helix-turn-helix domain. These domains are often DNA binding domains. When DNA binding was attempted, it was shown that ABD1, ABD2 and the tandem of ABD1 and ABD2 bound to DNA. The identification of the actin binding domain and the discovery of a novel DNA binding ability open up many more possible functions of ms1/STARS.
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Malakasi, Panagiota. "The regulation of oxidative stress response by a conserved response regulator protein in yeast." Thesis, University of Newcastle Upon Tyne, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273360.
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Jenkins, Mark 1979. "A role for the Drosophila eIF4E binding protein during stress response /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82256.
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The Drosophila melanogaster eIF4E binding protein (d4E-BP) inhibits translation initiation and is implicated in cell growth as a downstream effector of the Drosophila insulin signaling pathway. Since d4E-BP null flies show similar growth and development to control flies, the possibility of a conditional phenotype was explored through stress treatments. Adult d4E-BP null flies show sensitivity to oxidative stress, and d4E-BP null larvae die faster than controls under starvation and protein starvation. Expressing a mutant d4E-BP that doesn't bind to eIF4E in the d4E-BP null background does not rescue this stress sensitivity, which suggests that wild-type stress resistance requires binding of d4E-BP to eIF4E.The Drosophila forkhead transcription factor dFOXO is a transcriptional activator of d4E-BP. There is a strong reduction of d4E-BP peptide in a dFOXO null background. dFOXO null flies are also sensitive to oxidative stress, and rescue of this sensitivity through ectopic expression of UAS-d4E-BP(wt) in a dFOXO null background suggests d4E-BP is a downstream mediator of dFOXO oxidative stress resistance.
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Mahmood, Ahsan. "Role of SLMAP in Endoplasmic Reticulum Stress and Unfolded Protein Response." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24399.
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Cardiac function is regulated by the molecular components of the sarco/endoplasmic reticulum (ER/SR). Disruptions in homeostatic balance of these proteins and calcium regulation results in activation of ER stress response. Sarcolemmal membrane-associated proteins (SLMAPs) are found in cell membrane, SR/ER, and mitochondria. Overexpression of SLMAP in the myocardium has shown to impair excitation-contraction (E-C) coupling in the transgenic (Tg) mice. ER stress response was examined in Tg mice overexpressing SLMAP in the myocardium. In Tg hearts, changes observed in the expression of proteins involved in ER stress were dependent on the age and sex. SLMAP overexpression results in maladaptive ER stress response, as the mice age. Neonatal cardiomyocytes isolated from the Tg hearts showed decreased viability, upregulation of ER stress response proteins, which were sensitized to thapsigargin-induced stress, and desensitized to palmitate-induced oxidative stress. These findings suggest that normal SLMAP levels are important for proper cardiac function, and cell viability.
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Hearne, Catherine Mary. "A study of the heat shock response of Bacillus subtilis." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334111.
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Chalmers, Fiona. "Improving protein yield from mammalian cells by manipulation of stress response pathways." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7666/.
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Monoclonal antibodies are a class of therapeutic that is an expanding area of the lucrative biopharmaceutical industry. These complex proteins are predominantly produced from large cultures of mammalian cells; the industry standard cell line being Chinese Hamster Ovary (CHO) cells. A number of optimisation strategies have led to antibody titres from CHO cells increasing by a hundred-fold, and it has been proposed that a further bottleneck in biosynthesis is in protein folding and assembly within the secretory pathway. To alleviate this bottleneck, a CHO-derived host cell line was generated by researchers at the pharmaceutical company UCB that stably overexpressed two critical genes: XBP1, a transcription factor capable of expanding the endoplasmic reticulum and upregulating protein chaperones; and Ero1α, an oxidase that replenishes the machinery of disulphide bond formation. This host cell line, named CHO-S XE, was confirmed to have a high yield of secreted antibody. The work presented in this thesis further characterises CHO-S XE, with the aim of using the information gained to lead the generation of novel host cell lines with more optimal characteristics than CHO-S XE. In addition to antibodies, it was found that CHO-S XE had improved production of two other secreted proteins: one with a simple tertiary structure and one complex multi-domain protein; and higher levels of a number of endogenous protein chaperones. As a more controlled system of gene expression to unravel the specific roles of XBP1 and Ero1α in the secretory properties of CHO-S XE, CHO cells with inducible overexpression of XBP1, Ero1α, or a third gene involved in the Unfolded Protein Response, GADD34, were generated. From these cell lines, it was shown that more antibody was secreted by cells with induced overexpression of XBP1; however, Ero1α and GADD34 overexpression did not improve antibody yield. Further investigation revealed that endogenous XBP1 splicing was downregulated in the presence of an abundance of the active form of XBP1. This result indicated a novel aspect of the regulation of the activity of IRE1, the stress-induced endoribonuclease responsible for XBP1 splicing. Overall, the work described in this thesis confirms that the overexpression of XBP1 has an enhancing effect on the secretory properties of CHO cells; information which could contribute to the development of host cells with a greater capacity for antibody production.
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Muthevhuli, Mpho. "Investigation of the role of AtNOGC1, a guanylyl cyclase protein in response to abiotic and biotic stress." University of the Western Cape, 2018. http://hdl.handle.net/11394/6763.
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>Magister Scientiae - MScAgricultural production is one of the most important sectors which provide food for the growing world population which is estimated to reach 9.7 billion by 2050, thus there is a need to produce more food. Climate change, on the other hand, is negatively affecting major global crops such as maize, sorghum, wheat and barley. Environmental factors such as salinity, drought, high temperatures and pathogens affect plant production by oxidatively damaging the physiological processes in plants, leading to plant death. Poor irrigation used to combat drought result in salinasation, which is estimated to affect 50% of arable land by 2050. Plants have developed several mechanisms that protect them against stress and these include overexpression of stress responsive genes and altered signal transduction to change the expression of stress responsive genes, among others. Cyclic 3’5’ guanosine monophosphate (cGMP), a second messenger that is synthesised by guanylyl cyclase (GC), transmit signals to various cellular functions in plants during plant development, growth and response to abiotic and biotic stresses. Arabidopsis thaliana nitric oxide guanylyl cyclase 1 (AtNOGC1) is a guanylyl cyclase which upon activation by nitric oxide (NO) leads to the production of more cGMP. Cyclic GMP further activates protein kinases, ion gated channels and phosphodiesterase which mediate response to various stresses. In this project the role of AtNOGC1 was investigated in response to abiotic and biotic stresses through analysis of its evolutionary relationships, promoter, gene expression and functional analysis via the viability assays in Escherichia coli (E.coli). Phylogenetic tree, exon-intron structure and conserved motifs were analysed using the Molecular Evolutionary Genetics Analysis (MEGA V.7), Gene Structure Display Server 2.0 (GSDS 2.0), and Multiple Expectation Maximisation for Motif Elicitation (MEME) tools respectively. AtNOGC1’s gene expression was analysed by the Real-Time Quantitative Reverse Transcription Polymerase Reaction (qRT-PCR), whereas functional analysis was carried out using the cell viability (liquid and spot) assays to determine its ability to confer stress tolerance to E. coli.
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Nájar, Durán Elena. "Characterization of the maize protein ZmSTOP1 and its role in drought stress response." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/327875.
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El déficit hídrico se ha convertido un una gran amenaza hacia la producción agrícola en todo el mundo. La identificación de nuevos actores en la respuesta al estrés por sequía en plantas cultivables es vital para entender su adaptación a crecientes cambios ambientales.
El ácido abscísico (ABA) es una hormona vegetal que media las respuestas adaptativas a la sequía, como la dormancia de semillas, el cierre estomático y la detención del crecimiento de la raíz. En el caso de la regulación estomática, el ABA activa la quinasa OST1, que a su vez fosforila diferentes sustratos, por ejemplo NADPH oxidasas, canales iónicos y factores de transcripción, lo que al final conducirá al cierre estomático. Aunque el cierre estomático en respuesta a ABA es esencial para evitar la desecación y, por lo tanto, la muerte de la planta, se debe mantener un cierto nivel de conductividad estomática para permitir el intercambio de gases y la transpiración, esencial para la captación de agua y solutos a través de las raíces.
Hemos identificado y caracterizado un nuevo posible factor de transcripción dedo de zinc de tipo C2H2, homólogo a la proteína de Arabidopsis Sensitive to Proton Rhizotoxicity (STOP)1, la cual es crítica para la tolerancia a aluminio y protones en suelos ácidos. Hemos determinado que ZmSTOP1 es una proteína muy bien conservada entre especies, especialmente en sus cuatro dominios de tipo dedo de zinc, los cuales son característicos de las proteínas de tipo STOP1 en las plantas. ZmSTOP1 es miembro de una familia de cinco proteínas tipo STOP1 en maíz. Presenta localización nuclear y tiene la capacidad de unir ADN, aunque no se han podido identificar dianas específicas.
En este trabajo mostramos cómo ZmSTOP1 complementa el fenotipo característico de AtSTOP1 en condiciones de pH ácido. Además, detectamos que la sobreexpresión de ZmSTOP1 promueve una respuesta diferencial a ABA en raíces y hojas. El crecimiento de raíces está sobre inhibido, mientras que los estomas presentan insensibilidad a la señal de ABA, permaneciendo más abiertos que el control tras un tratamiento con ABA. Utilizando un análisis por microarray hemos podido determinar que los genes afectados por ZmSTOP1 se clasifican principalmente en señalización, regulación de la transcripción y estrés. Su sobreexpresión promueve cambios en el patrón de expresión de varios genes importantes para la homeostasis iónica y la señalización celular, como el canal de potasio KT2/3, el transportador de calcio CAX7, la NADPH oxidasa RBOHD, o la ATPasa de protones de membrana plasmática HA2, y puede inducir la expresión ectópica de estos genes en raíces u hojas. La desregulación de estos genes puede afectar el comportamiento global de la planta ante condiciones de estrés por sequía, ya que los efectos del ABA dependen profundamente en la homeostasis iónica, pudiendo representar una posible explicación para los fenotipos observados.
Adicionalmente, hemos establecido que esta proteína es interactor y sustrato de la quinasa OST1. La fosforilación por parte de esta quinasa modula el efecto de ZmSTOP1 en la regulación estomática.
En resumen, con la caracterización de la proteína ZmSTOP1 hemos arrojado luz sobre la compleja red que regula la tolerancia a estrés en una planta crucial para el consumo humano y animal como es el maíz. Estos resultados pueden ser importantes para enfocar futuras mejoras genéticas de la planta, ya sea por ingeniería genética o mediante mejora clásica.Water deficit has become a very important threat to agricultural yield worldwide. The identification of new players in drought stress response among crop plants is vital to understand their adaptation to increasing environmental challenges. Abscisic acid (ABA) is a plant hormone known to mediate drought adaptative responses such as seed dormancy, stomatal closure and root growth arrest. In the case of stomatal regulation, ABA drives the activation of OST1 kinase, which phosphorylates different substrates, for example NADPH oxidases, ionic channels and transcription factors, which will finally lead to stomatal closure. Although stomatal closure in response to ABA is essential to avoid desiccation, and thus, the death of the plant, a certain level of stomatal conductivity must be maintained to permit gas exchange and transpiration, essential to drive water and solutes uptake through the roots. We identified and characterized a new maize C2H2 zinc-finger putative transcription factor that presents homology to the Arabidopsis Sensitive to Proton Rhizotoxicity (STOP)1, which is critical for aluminum and proton tolerance in acidic soils. We determined that ZmSTOP1 is a well-conserved protein between plant species, especially in its four zinc-finger domains, which are characteristic of the STOP1-like proteins in plants. ZmSTOP1 is one of a five-members family of STOP1-like proteins in maize. It localizes in the nucleus, and has the ability to bind DNA, though no specific DNA targets were identified. In this work we show how ZmSTOP1 can complement AtSTOP1 phenotype in low pH conditions. Moreover, we detected that ZmSTOP1 overexpression promotes a differential response to ABA in roots and shoots. Root growth is over-inhibited whereas stomata present insensitivity to the ABA signal, remaining more open than the wild type after ABA treatment. Through microarray analyses we determine that the genes affected by ZmSTOP1 are classified mainly in signaling, regulation of transcription and stress. Its overexpression promotes changes in the expression pattern of several genes that are important for ionic homeostasis and signaling in cells, like the potassium channel KT2/3, the calcium transporter CAX7, the NADPH oxidase RBOHD, or the plasma membrane proton pump ATPase HA2, and it can induce ectopic expression of these genes in roots or shoots. The deregulation of these genes can affect the global behavior of the plant before drought stress conditions, as ABA effects depend deeply on ionic homeostasis, and could represent a possible explanation for the phenotypes observed. Additionally, we established that this protein is an interactor and a substrate of OST1 kinase. The phosphorylation by this kinase modulates ZmSTOP1 effect on stomatal regulation. In summary, by characterizing ZmSTOP1 protein we have shed light into the complex network regulating drought tolerance in a crucial plant for human and animal consumption like maize. These results can be important for focusing further genetic improvement of the plant, by either genetic engineering or classic breeding.
Books on the topic "Stress response protein p66ShcA"
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The unfolded protein response und cellular stress. Amsterdam [etc.]: Elsevier, 2011.
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Conn, P. Michael. The unfolded protein response and cellular stress. Amsterdam [etc.]: Elsevier, 2011.
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Conn, P. Michael. Methods in enzymology: The unfolded protein response and cellular stress. Amsterdam: Elsevier, 2011.
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Conn, P. Michael. Unfolded Protein Response and Cellular Stress, Part C. Elsevier Science & Technology Books, 2011.
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Conn, P. Michael. Unfolded Protein Response and Cellular Stress, Part B. Elsevier Science & Technology Books, 2011.
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Conn, P. Michael. Unfolded Protein Response and Cellular Stress, Part A. Elsevier Science & Technology Books, 2011.
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The Unfolded Protein Response and Cellular Stress, Part A. Elsevier, 2011. http://dx.doi.org/10.1016/c2010-0-66637-5.
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The Unfolded Protein Response and Cellular Stress, Part B. Elsevier, 2011. http://dx.doi.org/10.1016/c2010-0-66638-7.
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The Unfolded Protein Response and Cellular Stress, Part C. Elsevier, 2011. http://dx.doi.org/10.1016/c2010-0-66908-2.
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Csermely, Peter, and László Vígh. Molecular Aspects of the Stress Response: Chaperones, Membranes and Networks. Springer London, Limited, 2007.
Find full textBook chapters on the topic "Stress response protein p66ShcA"
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Liao, Nan, and Linda M. Hendershot. "Unfolded Protein Response: Contributions to Development and Disease." In Cell Stress Proteins, 57–88. New York, NY: Springer New York, 2007. http://dx.doi.org/10.1007/978-0-387-39717-7_4.
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Norberg, Åke, Felix Liebau, and Jan Wernerman. "Protein Metabolism." In The Stress Response of Critical Illness: Metabolic and Hormonal Aspects, 95–106. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-27687-8_9.
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Mohanta, Tapan Kumar, and Alok Krishna Sinha. "Role of Calcium-Dependent Protein Kinases during Abiotic Stress Tolerance." In Abiotic Stress Response in Plants, 185–206. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2016. http://dx.doi.org/10.1002/9783527694570.ch9.
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Lhomond, Stéphanie, and Eric Chevet. "Signaling the Unfolded Protein Response in cancer." In Endoplasmic Reticulum Stress in Health and Disease, 357–82. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-4351-9_16.
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Deka, Kamalakshi, and Sougata Saha. "Regulation of Mammalian HSP70 Expression and Stress Response." In Regulation of Heat Shock Protein Responses, 3–25. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-74715-6_1.
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Damaris, Rebecca Njeri, and Pingfang Yang. "Protein Phosphorylation Response to Abiotic Stress in Plants." In Plant Phosphoproteomics, 17–43. New York, NY: Springer US, 2021. http://dx.doi.org/10.1007/978-1-0716-1625-3_2.
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Mukhopadhyay, Adhip, and Manoj Kumar. "Phage Shock Protein-Mediated Stress Response in Bacteria." In ACS Symposium Series, 43–57. Washington, DC: American Chemical Society, 2023. http://dx.doi.org/10.1021/bk-2023-1434.ch003.
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Kumari, Supriya, and Nandula Raghuram. "Protein Phosphatases in N Response and NUE in Crops." In Protein Phosphatases and Stress Management in Plants, 233–44. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-48733-1_12.
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Gerlach, Jared Q., Shashank Sharma, Kirk J. Leister, and Lokesh Joshi. "A Tight-Knit Group: Protein Glycosylation, Endoplasmic Reticulum Stress and the Unfolded Protein Response." In Endoplasmic Reticulum Stress in Health and Disease, 23–39. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-4351-9_2.
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Beckerman, Martin. "Chaperones, Endoplasmic Reticulum Stress, and the Unfolded Protein Response." In Cellular Signaling in Health and Disease, 391–410. New York, NY: Springer US, 2009. http://dx.doi.org/10.1007/978-0-387-98173-4_18.
Full textConference papers on the topic "Stress response protein p66ShcA"
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Kryvenko, V., W. Seeger, and I. Vadász. "Hypercapnia impairs protein translation by activating integrated stress response." In Herbsttagung der Sektionen Zellbiologie und Infektiologie und Tuberkulose der Deutschen Gesellschaft für Pneumologie und Beatmungsmedizin e.V. Georg Thieme Verlag KG, 2018. http://dx.doi.org/10.1055/s-0037-1615334.
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Gewandter, JS, and MA O'Reilly. "Loss of the ER Stress Sensor Protein, BiP, in Hyperoxia Does Not Activate the Classic ER Stress Response." In American Thoracic Society 2009 International Conference, May 15-20, 2009 • San Diego, California. American Thoracic Society, 2009. http://dx.doi.org/10.1164/ajrccm-conference.2009.179.1_meetingabstracts.a4183.
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Banerjee, Aditi, Elizabeth Duran, Javier Couto, Zhenbo Zhang, Lydia A. Espinoza, Marina Torres, Sushanta K. Banerjee, Krishna Baksi, and Dipak K. Banerjee. "Abstract 2313: ER stress-mediated unfolded protein response inhibits angiogenesis and breast tumor growth." In Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL. American Association for Cancer Research, 2012. http://dx.doi.org/10.1158/1538-7445.am2012-2313.
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Kawahara, Kohichi, Takuto Kawahata, Fumito Horikuchi, Yohei Kamijo, Masatatsu Yamamoto, Yoshinari Shinsato, Kentaro Minami, Kazunari Arima, Toshiyuki Hamada, and Tatsuhiko Furukawa. "Abstract 5420: Ribosomal protein-p53-MDM2 signaling by nucleolar stress response and drug discovery." In Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA. American Association for Cancer Research, 2015. http://dx.doi.org/10.1158/1538-7445.am2015-5420.
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Hammond, Ester M. "Abstract IA-015: Hypoxia-induced SETX links replication stress with the unfolded protein response." In Abstracts: AACR Virtual Special Conference on Radiation Science and Medicine; March 2-3, 2021. American Association for Cancer Research, 2021. http://dx.doi.org/10.1158/1557-3265.radsci21-ia-015.
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Wang, Yugang, Yu Ning, Goleeta Alam, Fernanda Visioli, Jacques E. Nör, and Peter J. Polverini. "Abstract 2081: The unfolded protein response relieves stress in tumor cells by stimulating angiogenesis." In Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL. American Association for Cancer Research, 2011. http://dx.doi.org/10.1158/1538-7445.am2011-2081.
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Liu, Xian-De, Soyoung Ko, Qian Xiang, and Tony N. Eissa. "Alis Formation Is A Cytosolic Unfolded Protein Response To Inflammation And Endoplasmic Reticulum Stress." In American Thoracic Society 2011 International Conference, May 13-18, 2011 • Denver Colorado. American Thoracic Society, 2011. http://dx.doi.org/10.1164/ajrccm-conference.2011.183.1_meetingabstracts.a2127.
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Kemeny, Steven F., and Alisa Morss Clyne. "High Glucose Alters Endothelial Cell Response to Shear Stress." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206531.
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Endothelial cells line the walls of all blood vessels, where they maintain homeostasis through control of vascular tone, permeability, inflammation, and the growth and regression of blood vessels. Endothelial cells are mechanosensitive to fluid shear stress, elongating and aligning in the flow direction [1–2]. This shape change is driven by rearrangement of the actin cytoskeleton and focal adhesions [2]. Hyperglycemia, a hallmark of diabetes, affects endothelial cell function. High glucose has been shown to increase protein kinase C, formation of glucose-derived advanced glycation end-products, and glucose flux through the aldose reductase pathway within endothelial cells [3]. These changes are thought to be related to increased reactive oxygen species production [4]. While endothelial cell mechanics have been widely studied in healthy conditions, many disease states have yet to be explored. Biochemical alterations related to high glucose may alter endothelial cell mechanics.
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Conn, Crystal S., Hao G. Nguyen, Yae Kye, John T. Cunningham, Charles Truillet, Michael Evans, Tony L. Huynh, Peter Walters, and Davide Ruggero. "Abstract A25: Sensing stress in cancer: a novel therapy targeting protein synthesis through the unfolded protein response in prostate cancer development." In Abstracts: AACR Special Conference on Translational Control of Cancer: A New Frontier in Cancer Biology and Therapy; October 27-30, 2016; San Francisco, CA. American Association for Cancer Research, 2017. http://dx.doi.org/10.1158/1538-7445.transcontrol16-a25.
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Cheung, Tracy M., and George A. Truskey. "Aging Endothelial Cells Exhibit Decreased Response to Atheroprotective Shear Stress." In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14402.
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As endothelial cells (ECs) age, morphological and physiological changes occur that may alter macromolecular transport and cause subsequent disease development. ECs in atherosclerotic regions exhibit high cell turnover and high levels of oxidative stress due to transient flow patterns and low and oscillating shear stress. This leads to replicative or stress-induced senescence. Resveratrol indirectly reverses senescence-associated phenotypes via competitive inhibition of cAMP-degrading phosphodiesterases (PDEs). Elevated levels of membrane-associated cAMP activate the cyclic AMP-regulated guanosine nucleotide exchange factor Epac1 which, in turn, leads to guanosine triphosphate (GTP) binding to the small G protein Rap1. GTP bound Rap1 activates the deacetylase SIRTUIN1 (SIRT1) but also causes changes to the cortical cytoskeleton and organization of VE-cadherin mechanosensor in the endothelial junctions (Figure 1).
Reports on the topic "Stress response protein p66ShcA"
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Dyer, Scott D., Kenneth L. Dickson, and Earl G. Zimmerman. Evaluation of the Efficacy of the Stress Protein Response as a Biochemical Water Quality Biomonitoring Method. Fort Belvoir, VA: Defense Technical Information Center, December 1990. http://dx.doi.org/10.21236/ada231966.
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Bray, Elizabeth, Zvi Lerner, and Alexander Poljakoff-Mayber. The Role of Phytohormones in the Response of Plants to Salinity Stress. United States Department of Agriculture, September 1994. http://dx.doi.org/10.32747/1994.7613007.bard.
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Salinity is an increasing problem in many irrigated areas of crop production and is a significant factor in reducing crop productivity. Developmental, physiological, and molecular responses to salinity were studied in order to improve our understanding of these responses. Improvements in our understanding of plant responses to salinity are necessary in order to develop crops with improved salt tolerance. Previously, in Israel, it was shown that Sorghum biccolor can adapt to an otherwise lethal concentration of NaCl. These experiments were refined and it was shown that there is a specific window of development in which this adaption can occur. Past the window of development, Sorghum plants can not be adapted. In addition, the ability to adapt is not present in all genotypes of Sorghum. Cultivars that adapt have an increased coefficient of variation for many of the physiological parameters measured during the mid-phase of adaptation. Therefore, it is possible that the adaptation process does not occur identically in the entire population. A novel gene was identified, isolated and characterized from Sorghum that is induced in roots in response to salinity. This gene is expressed in roots in response to salt treatments, but it is not salt-induced in leaves. In leaves, the gene is expressed without a salt treatment. The gene encodes a proline-rich protein with a novel proline repeat, PEPK, repeated more than 50 times. An antibody produced to the PEPK repeat was used to show that the PEPK protein is present in the endodermal cell wall of the root during salt treatments. In the leaves, the protein is also found predominantly in the cell wall and is present mainly in the mesophyll cells. It is proposed that this protein is involved in the maintenance of solute concentration.
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Locy, Robert D., Hillel Fromm, Joe H. Cherry, and Narendra K. Singh. Regulation of Arabidopsis Glutamate Decarboxylase in Response to Heat Stress: Modulation of Enzyme Activity and Gene Expression. United States Department of Agriculture, January 2001. http://dx.doi.org/10.32747/2001.7575288.bard.
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Most plants accumulate the nonprotein amino acid, g-aminobutyric acid (GABA), in response to heat stress. GABA is made from glutamate in a reaction catalyzed by glutamate decarboxylase (GAD), an enzyme that has been shown by the Israeli PI to be a calmodulin (CaM) binding protein whose activity is regulated in vitro by calcium and CaM. In Arabidopsis there are at least 5 GAD genes, two isoforms of GAD, GAD1 and GAD2, are known to be expressed, both of which appear to be calmodulin-binding proteins. The role of GABA accumulation in stress tolerance remains unclear, and thus the objectives of the proposed work are intended to clarify the possible roles of GABA in stress tolerance by studying the factors which regulate the activity of GAD in vivo. Our intent was to demonstrate the factors that mediate the expression of GAD activity by analyzing the promoters of the GAD1 and GAD2 genes, to determine the role of stress induced calcium signaling in the regulation of GAD activity, to investigate the role of phosphorylation of the CaM-binding domain in the regulation of GAD activity, and to investigate whether ABA signaling could be involved in GAD regulation via the following set of original Project Objectives: 1. Construction of chimeric GAD1 and GAD2 promoter/reporter gene fusions and their utilization for determining cell-specific expression of GAD genes in Arabidopsis. 2. Utilizing transgenic plants harboring chimeric GAD1 promoter-luciferase constructs for isolating mutants in genes controlling GAD1 gene activation in response to heat shock. 3. Assess the role of Ca2+/CaM in the regulation of GAD activity in vivo in Arabidopsis. 4. Study the possible phosphorylation of GAD as a means of regulation of GAD activity. 5. Utilize ABA mutants of Arabidopsis to assess the involvement of this phytohormone in GAD activation by stress stimuli. The major conclusions of Objective 1 was that GAD1 was strongly expressed in the elongating region of the root, while GAD2 was mainly expressed along the phloem in both roots and shoots. In addition, GAD activity was found not to be transcriptionally regulated in response to heat stress. Subsequently, The Israeli side obtained a GAD1 knockout mutation, and in light of the objective 1 results it was determined that characterization of this knockout mutation would contribute more to the project than the proposed Objective 2. The major conclusion of Objective 3 is that heat-stress-induced changes in GAD activity can be explained by heat-stress-induced changes in cytosolic calcium levels. No evidence that GAD activity was transcriptionally or translationally regulated or that protein phosphorylation was involved in GAD regulation (objective 4) was obtained. Previously published data by others showing that in wheat roots ABA regulated GABA accumulation proved not to be the case in Arabidopsis (Objective 5). Consequently, we put the remaining effort in the project into the selection of mutants related to temperature adaptation and GABA utilization and attempting to characterize events resulting from GABA accumulation. A set of 3 heat sensitive mutants that appear to have GABA related mutations have been isolated and partially characterized, and a study linking GABA accumulation to growth stimulation and altered nitrate assimilation were conducted. By providing a better understanding of how GAD activity was and was not regulated in vivo, we have ruled out the use of certain genes for genetically engineering thermotolerance, and suggested other areas of endeavor related to the thrust of the project that may be more likely approaches to genetically engineering thermotolerance.
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Sela, Shlomo, and Michael McClelland. Investigation of a new mechanism of desiccation-stress tolerance in Salmonella. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7598155.bard.
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Low-moisture foods (LMF) are increasingly involved in foodborne illness. While bacteria cannot grow in LMF due to the low water content, pathogens such as Salmonella can still survive in dry foods and pose health risks to consumer. We recently found that Salmonella secretes a proteinaceous compound during desiccation, which we identified as OsmY, an osmotic stress response protein of 177 amino acids. To elucidate the role of OsmY in conferring tolerance against desiccation and other stresses in Salmonella entericaserovarTyphimurium (STm), our specific objectives were: (1) Characterize the involvement of OsmY in desiccation tolerance; (2) Perform structure-function analysis of OsmY; (3) Study OsmY expression under various growth- and environmental conditions of relevance to agriculture; (4) Examine the involvement of OsmY in response to other stresses of relevance to agriculture; and (5) Elucidate regulatory pathways involved in controlling osmY expression. We demonstrated that an osmY-mutant strain is impaired in both desiccation tolerance (DT) and in long-term persistence during cold storage (LTP). Genetic complementation and addition of a recombinantOsmY (rOsmY) restored the mutant survival back to that of the wild type (wt). To analyze the function of specific domains we have generated a recombinantOsmY (rOsmY) protein. A dose-response DT study showed that rOsmY has the highest protection at a concentration of 0.5 nM. This effect was protein- specific as a comparable amount of bovine serum albumin, an unrelated protein, had a three-time lower protection level. Further characterization of OsmY revealed that the protein has a surfactant activity and is involved in swarming motility. OsmY was shown to facilitate biofilm formation during dehydration but not during bacterial growth under optimal growth conditions. This finding suggests that expression and secretion of OsmY under stress conditions was potentially associated with facilitating biofilm production. OsmY contains two conserved BON domains. To better understand the role of the BON sites in OsmY-mediated dehydration tolerance, we have generated two additional rOsmY constructs, lacking either BON1 or BON2 sites. BON1-minus (but not BON2) protein has decreased dehydration tolerance compared to intact rOsmY, suggesting that BON1 is required for maximal OsmY-mediated activity. Addition of BON1-peptide at concentration below 0.4 µM did not affect STm survival. Interestingly, a toxic effect of BON1 peptide was observed in concentration as low as 0.4 µM. Higher concentrations resulted in complete abrogation of the rOsmY effect, supporting the notion that BON-mediated interaction is essential for rOsmY activity. We performed extensive analysis of RNA expression of STm undergoing desiccation after exponential and stationary growth, identifying all categories of genes that are differentially expressed during this process. We also performed massively in-parallel screening of all genes in which mutation caused changes in fitness during drying, identifying over 400 such genes, which are now undergoing confirmation. As expected OsmY is one of these genes. In conclusion, this is the first study to identify that OsmY protein secreted during dehydration contributes to desiccation tolerance in Salmonella by facilitating dehydration- mediated biofilm formation. Expression of OsmY also enhances swarming motility, apparently through its surfactant activity. The BON1 domain is required for full OsmY activity, demonstrating a potential intervention to reduce pathogen survival in food processing. Expression and fitness screens have begun to elucidate the processes of desiccation, with the potential to uncover additional specific targets for efforts to mitigate pathogen survival in desiccation.
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Guy, Charles, Gozal Ben-Hayyim, Gloria Moore, Doron Holland, and Yuval Eshdat. Common Mechanisms of Response to the Stresses of High Salinity and Low Temperature and Genetic Mapping of Stress Tolerance Loci in Citrus. United States Department of Agriculture, May 1995. http://dx.doi.org/10.32747/1995.7613013.bard.
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The objectives that were outlined in our original proposal have largely been achieved or will be so by the end of the project in February 1995 with one exception; that of mapping cold tolerance loci based on the segregation of tolerance in the BC1 progeny population. Briefly, our goals were to 1) construct a densely populated linkage map of the citrus genome: 2) map loci important in cold and/or salt stress tolerance; and 3) characterize the expression of genes responsive to cold land salt stress. As can be seen by the preceding listing of accomplishments, our original objectives A and B have been realized, objective C has been partially tested, objective D has been completed, and work on objectives E and F will be completed by the end of 1995. Although we have yet to map any loci that contribute to an ability of citrus to maintain growth when irrigated with saline water, our very encouraging results from the 1993 experiment provides us with considerable hope that 1994's much more comprehensive and better controlled experiment will yield the desired results once the data has been fully analyzed. Part of our optimism derives from the findings that loci for growth are closely linked with loci associated with foliar Cl- and Na+ accumulation patterns under non-salinization conditions. In the 1994 experiment, if ion exclusion or sequestration traits are segregating in the population, the experimental design will permit their resolution. Our fortunes with respect to cold tolerance is another situation. In three attempts to quantitatively characterize cold tolerance as an LT50, the results have been too variable and the incremental differences between sensitive and tolerant too small to use for mapping. To adequately determine the LT50 requires many plants, many more than we have been able to generate in the time and space available by making cuttings from small greenhouse-grown stock plants. As it has turned out, with citrus, to prepare enough plants needed to be successful in this objective would have required extensive facilities for both growing and testing hardiness which simply were not available at University of Florida. The large populations necessary to overcome the variability we encountered was unanticipated and unforeseeable at the project's outset. In spite of the setbacks, this project, when it is finally complete will be exceedingly successful. Listing of Accomplishments During the funded interval we have accomplished the following objectives: Developed a reasonably high density linkage map for citrus - mapped the loci for two cold responsive genes that were cloned from Poncirus - mapped the loci for csa, the salt responsive gene for glutathione peroxidase, and ccr a circadian rhythm gene from citrus - identified loci that confer parental derived specific DNA methylation patterns in the Citrus X Poncirus cross - mapped 5 loci that determine shoot vigor - mapped 2 loci that influence leaf Na+ accumulation patterns under non-saline conditions in the BC1 population - mapped 3 loci that influence leaf Na+ accumulation paterns during salt sress - mapped 2 loci that control leaf Cl- accumulation patterns under non-saline conditions - mapped a locus that controls leaf Cl- accumulation patterns during salt stress Screened the BC1 population for growth reduction during salinization (controls and salinized), and cold tolerance - determined population variation for shoot/root ratio of Na+ and Cl- - determined levels for 12 inorganic nutrient elements in an effort to examine the influence of salinization on ion content with emphasis on foliar responses - collected data on ion distribution to reveal patterns of exclusion/sequestration/ accumulation - analyzed relationships between ion content and growth Characterization of gene expression in response to salt or cold stress - cloned the gene for the salt responsive protein csa, identified it as glutathione peroxidase, determined the potential target substrate from enzymatic studies - cloned two other genes responsive to salt stress, one for the citrus homologue of a Lea5, and the other for an "oleosin" like gene - cold regulated (cor) genes belonging to five hybridization classes were isolated from Poncirus, two belonged to the group 2 Lea superfamily of stress proteins, the others show no significant homology to other known sequences - the expression of csa during cold acclimation was examined, and the expression of some of the cor genes were examined in response to salt stress - the influence of salinization on cold tolerance has been examined with seedling populations - conducted protein blot studies for expression of cold stress proteins during salt stress and vice versa
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Barash, Itamar, and Robert Rhoads. Translational Mechanisms Governing Milk Protein Levels and Composition. United States Department of Agriculture, 2006. http://dx.doi.org/10.32747/2006.7696526.bard.
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Original objectives: The long-term goal of the research is to achieve higher protein content in the milk of ruminants by modulating the translational apparatus of the mammary gland genetically, nutritionally, or pharmacologically. The short-term objectives are to obtain a better understanding of 1) the role of amino acids (AA) as regulators of translation in bovine and mouse mammary epithelial cells and 2) the mechanism responsible for the synergistic enhancement of milk-protein mRNA polyadenylation by insulin and prolactin. Background of the topic: In many cell types and tissues, individual AA affect a signaling pathway which parallels the insulin pathway to modulate rates and levels of protein synthesis. Diverse nutritional and hormonal conditions are funneled to mTOR, a multidomain serine/threonine kinase that regulates a number of components in the initiation and elongation stages of translation. The mechanism by which AA signal mTOR is largely unknown. During the current grant period, we have studied the effect of essential AA on mechanisms involved in protein synthesis in differentiated mammary epithelial cells cultured under lactogenic conditions. We also studied lactogenic hormone regulation of milk protein synthesis in differentiated mammary epithelial cells. In the first BARD grant (2000-03), we discovered a novel mechanism for mRNA-specific hormone-regulated translation, namely, that the combination of insulin plus prolactin causes cytoplasmic polyadenylation of milk protein mRNAs, which leads to their efficient translation. In the current BARD grant, we have pursued the signaling pathways of this novel hormone action. Major conclusions/solutions/achievements: The positive and negative signaling from AA to the mTOR pathway, combined with modulation of insulin sensitization, mediates the synthesis rates of total and specific milk proteins in mammary epithelial cells. The current in vitro study revealed cryptic negative effects of Lys, His, and Thr on cellular mechanisms regulating translation initiation and protein synthesis in mammary epithelial cells that could not be detected by conventional in vivo analyses. We also showed that a signaling pathway involving Jak2 and Stat5, previously shown to lead from the prolactin receptor to transcription of milk protein genes, is also used for cytoplasmic polyadenylation of milk protein mRNAs, thereby stabilizing these mRNAs and activating them for translation. Implications: In vivo, plasma AA levels are affected by nutritional and hormonal effects as well as by conditions of exercise and stress. The amplitude in plasma AA levels resembles that applied in the current in vitro study. Thus, by changing plasma AA levels in the epithelial cell microenvironment or by sensitizing the mTOR pathway to their presence, it should be possible to modulate the rate of milk protein synthesis. Furthermore, knowledge that phosphorylation of Stat5 is required for enhanced milk protein synthesis in response to lactogenic opens the possibility for pharmacologic approaches to increase the phosphorylation of Stat5 and, thereby, milk protein production.
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Hansen, Peter J., Zvi Roth, and Jeremy J. Block. Improving oocyte competence in dairy cows exposed to heat stress. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7598163.bard.
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Original Objectives. The overall goal is to develop methods to increase pregnancy rate in lactating dairy cows exposed to heat stress through methods that minimize damage to the oocyte and embryo caused by heat stress. Objectives were as follows: (1) examine the protective effects of melatonin on developmental competence of oocytes exposed to elevated temperature in vitro; (2) test whether melatonin feeding can improve developmental competence of oocytes in vivo and, if so, whether effects are limited to the summer or also occur in the absence of heat stress; and (3) evaluate the effectiveness of improving fertility by facilitating follicular turnover in the summer and winter. Revised Objectives. (1) Examine protective effects of melatonin and follicular fluid on developmental competence of oocytes exposed to elevated temperature in vitro; (2) examine the protective effects of melatonin on developmental competence of embryos exposed to elevated temperature in vitro; (3) evaluate effectiveness of improving fertility by administering human chorionicgonadotropin (hCG) to increase circulating concentrations of progesterone and evaluate whether response to hCG depends upon genotype for four mutations reported to be related to cow fertility; and (4) identify genes with allelic variants that increase resistance of embryos to heat shock. Background. The overall hypothesis is that pregnancy success is reduced by heat stress because of damage to the oocyte and cleavage-stage embryo mediated by reactive oxygen species (ROS), and that fertility can be improved by provision of antioxidants or by removing follicles containing oocytes damaged by heat stress. During the study, additional evidence from the literature indicated the potential importance of treatment with chorionicgonadotropin to increase fertility of heat- stressed cows and results from other studies in our laboratories implicated genotype as an important determinant of cow fertility. Thus, the project was expanded to evaluate hCG treatment and to identify whether fertility response to hCG depended upon single nucleotide polymorphisms (SNP) in genes implicated as important for cow fertility. We also evaluated whether a SNP in a gene important for cellular resistance to heat stress (HSPA1L, a member of the heat shock protein 70 family) is important for embryonic resistance to elevated temperature. Major conclusions, solutions & achievements. Results confirmed that elevated temperature increases ROS production by the oocyte and embryo and that melatonin decreases ROS. Melatonin reduced, but did not completely block, damaging effects of heat shock on the oocyte and had no effect on development of the embryo. Melatonin was protective to the oocyte at 0.1-1 μM, a concentration too high to be achieved in cows. It was concluded that melatonin is unlikely to be a useful molecule for increasing fertility of heat-stressed cows. Treatment with hCG at day 5 after breeding increased first-service pregnancy rate for primiparous cows but not for multiparous cows. Thus, hCG could be useful for increasing fertility in first-parity cows. The effectiveness of hCG depended upon genotype for a SNP in COQ9, a gene encoding for a mitochondrial-function protein. This result points the way to future efforts to use genetic information to identify populations of cows for which hormone treatments will be effective or ineffective. The SNP in HSPA1L was related to embryonic survival after heat shock. Perhaps, genetic selection for mutations that increase cellular resistance to heat shock could be employed to reduce effects of heat stress on fertility. Implications, both scientific and agricultural. This project has resulted in abandonment of one possible approach to improve fertility of the heat-stressed cow (melatonin therapy) while also leading to a method for improving fertility of primiparous cows exposed to heat stress (hCG treatment) that can be implemented on farms today. Genetic studies have pointed the way to using genetic information to 1) tailor hormonal treatments to cow populations likely to respond favorably and 2) select animals whose embryos have superior resistance to elevated body temperatures.
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Porat, Ron, Gregory T. McCollum, Amnon Lers, and Charles L. Guy. Identification and characterization of genes involved in the acquisition of chilling tolerance in citrus fruit. United States Department of Agriculture, December 2007. http://dx.doi.org/10.32747/2007.7587727.bard.
Full textAbstract:
Citrus, like many other tropical and subtropical fruit are sensitive to chilling temperatures. However, application of a pre-storage temperature conditioning (CD) treatment at 16°C for 7 d or of a hot water brushing (HWB) treatment at 60°C for 20 sec remarkably enhances chilling tolerance and reduces the development of chilling injuries (CI) upon storage at 5°C. In the current research, we proposed to identify and characterize grapefruit genes that are induced by CD, and may contribute to the acquisition of fruit chilling tolerance, by two different molecular approaches: cDNA array analysis and PCR cDNA subtraction. In addition, following the recent development and commercialization of the new Affymetrix Citrus Genome Array, we further performed genome-wide transcript profiling analysis following exposure to CD and chilling treatments. To conduct the cDNA array analysis, we constructed cDNA libraries from the peel tissue of CD- and HWB-treated grapefruit, and performed an EST sequencing project including sequencing of 3,456 cDNAs from each library. Based on the obtained sequence information, we chose 70 stress-responsive and chilling-related genes and spotted them on nylon membranes. Following hybridization the constructed cDNA arrays with RNA probes from control and CD-treated fruit and detailed confirmations by RT-PCR analysis, we found that six genes: lipid-transfer protein, metallothionein-like protein, catalase, GTP-binding protein, Lea5, and stress-responsive zinc finger protein, showed higher transcript levels in flavedo of conditioned than in non-conditioned fruit stored at 5 ᵒC. The transcript levels of another four genes: galactinol synthase, ACC oxidase, temperature-induced lipocalin, and chilling-inducible oxygenase, increased only in control untreated fruit but not in chilling-tolerant CD-treated fruit. By PCR cDNA subtraction analysis we identified 17 new chilling-responsive and HWB- and CD-induced genes. Overall, characterization of the expression patterns of these genes as well as of 11 more stress-related genes by RNA gel blot hybridizations revealed that the HWB treatment activated mainly the expression of stress-related genes(HSP19-I, HSP19-II, dehydrin, universal stress protein, EIN2, 1,3;4-β-D-glucanase, and SOD), whereas the CD treatment activated mainly the expression of lipid modification enzymes, including fatty acid disaturase2 (FAD2) and lipid transfer protein (LTP). Genome wide transcriptional profiling analysis using the newly developed Affymetrix Citrus GeneChip® microarray (including 30,171 citrus probe sets) revealed the identification of three different chilling-related regulons: 1,345 probe sets were significantly affected by chilling in both control and CD-treated fruits (chilling-response regulon), 509 probe sets were unique to the CD-treated fruits (chilling tolerance regulon), and 417 probe sets were unique to the chilling-sensitive control fruits (chilling stress regulon). Overall, exposure to chilling led to expression governed arrest of general cellular metabolic activity, including concretive down-regulation of cell wall, pathogen defense, photosynthesis, respiration, and protein, nucleic acid and secondary metabolism. On the other hand, chilling enhanced various adaptation processes, such as changes in the expression levels of transcripts related to membranes, lipid, sterol and carbohydrate metabolism, stress stimuli, hormone biosynthesis, and modifications in DNA binding and transcription factors.
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Sela, Shlomo, and Michael McClelland. Desiccation Tolerance in Salmonella and its Implications. United States Department of Agriculture, May 2013. http://dx.doi.org/10.32747/2013.7594389.bard.
Full textAbstract:
Salmonella enterica is a worldwide food-borne pathogen, which regularly causes large outbreaks of food poisoning. Recent outbreaks linked to consumption of contaminated foods with low water-activity, have raised interest in understanding the factors that control fitness of this pathogen to dry environment. Consequently, the general objective of this study was to extend our knowledge on desiccation tolerance and long-term persistence of Salmonella. We discovered that dehydrated STm entered into a viable-but-nonculturable state, and that addition of chloramphenicol reduced bacterial survival. This finding implied that adaptation to desiccation stress requires de-novo protein synthesis. We also discovered that dried STm cells develop cross-tolerance to multiple stresses that the pathogen might encounter in the agriculture/food environment, such as high or low temperatures, salt, and various disinfectants. These findings have important implications for food safety because they demonstrate the limitations of chemical and physical treatments currently utilized by the food industry to completely inactivate Salmonella. In order to identify genes involved in desiccation stress tolerance, we employed transcriptomic analysis of dehydrated and wet cells and direct screening of knock-out mutant and transposon libraries. Transcriptomic analysis revealed that dehydration induced expression of ninety genes and down-regulated seven. Ribosomal structural genes represented the most abundant functional group with a relatively higher transcription during dehydration. Other large classes of induced functional groups included genes involved in amino acid metabolism, energy production, ion transport, transcription, and stress response. Initial genetic analysis of a number of up-regulated genes was carried out). It was found that mutations in rpoS, yahO, aceA, nifU, rpoE, ddg,fnr and kdpE significantly compromised desiccation tolerance, supporting their role in desiccation stress response.
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Bercovier, Herve, Raul Barletta, and Shlomo Sela. Characterization and Immunogenicity of Mycobacterium paratuberculosis Secreted and Cellular Proteins. United States Department of Agriculture, January 1996. http://dx.doi.org/10.32747/1996.7573078.bard.
Full textAbstract:
Our long-term goal is to develop an efficient acellular vaccine against paratuberculosis based on protein antigen(s). A prerequisite to achieve this goal is to analyze and characterize Mycobacterium paratuberculosis (Mpt) secreted and cellular proteins eliciting a protective immune response. In the context of this general objective, we proposed to identify, clone, produce, and characterize: the Mpt 85B antigen and other Mpt immunoreactive secreted proteins, the Mpt L7/L12 ribosomal protein and other immunoreactive cellular proteins, Mpt protein determinants involved in invasion of epithelial cells, and Mpt protein antigens specifically expressed in macrophages. Paratuberculosis is still a very serious problem in Israel and in the USA. In the USA, a recent survey evaluated that 21.6% of the dairy herd were infected with Mpt resulting in 200-250 million dollars in annual losses. Very little is known on the virulence factors and on protective antigens of Mpt. At present, the only means of controlling this disease are culling or vaccination. The current vaccines do not allow a clear differentiation between infected and vaccinated animals. Our long-term goal is to develop an efficient acellular paratuberculosis vaccine based on Mpt protein antigen(s) compatible with diagnostic tests. To achieve this goal it is necessary to analyze and characterize secreted and cellular proteins candidate for such a vaccine. Representative Mpt libraries (shuttle plasmid and phage) were constructed and used to study Mpt genes and gene products described below and will be made available to other research groups. In addition, two approaches were performed which did not yield the expected results. Mav or Mpt DNA genes that confer upon Msg or E. coli the ability to invade and/or survive within HEp-2 cells were not identified. Likewise, we were unable to characterize the 34-39 kDa induced secreted proteins induced by stress factors due to technical difficulties inherent to the complexity of the media needed to support substantial M. pt growth. We identified, isolated, sequenced five Mpt proteins and expressed four of them as recombinant proteins that allowed the study of their immunological properties in sensitized mice. The AphC protein, found to be up regulated by low iron environment, and the SOD protein are both involved in protecting mycobacteria against damage and killing by reactive oxygen (Sod) and nitrogen (AhpC) intermediates, the main bactericidal mechanisms of phagocytic cells. SOD and L7/L12 ribosomal proteins are structural proteins constitutively expressed. 85B and CFP20 are both secreted proteins. SOD, L7/L12, 85B and CFP20 were shown to induce a Th1 response in immunized mice whereas AphC was shown by others to have a similar activity. These proteins did not interfere with the DTH reaction of naturally infected cows. Cellular immunity provides protection in mycobacterial infections, therefore molecules inducing cellular immunity and preferentially a Th1 pathway will be the best candidate for the development of an acellular vaccine. The proteins characterized in this grant that induce a cell-mediated immunity and seem compatible with diagnostic tests, are good candidates for the construction of a future acellular vaccine.