The Experts below are selected from a list of 159750 Experts worldwide ranked by ideXlab platform
Michel Vidaud - One of the best experts on this subject based on the ideXlab platform.
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quantitation of myc Gene expression in sporadic breast tumors with a real time reverse transcription pcr assay
Cancer Research, 1999Co-Authors: Ivan Bieche, Ingrid Laurendeau, Sengul Tozlu, Martine Olivi, Dominique Vidaud, Rosette Lidereau, Michel VidaudAbstract:MYC Gene Overexpression was identified recently as a downstream step at the end of the Wnt/APC/β-catenin pathway dysregulation observed in colorectal cancer (T-C. He et al. , Science (Washington DC), 281: 1509–1512, 1998). It thus appears that an excess of c-myc protein is a primary cause of numerous cancers. In breast cancer, MYC has been studied mostly at the DNA level because of the poor quality of available antibodies against the protein product. The renewed interest in MYC calls for a sensitive and accurate method for analyzing MYC Overexpression in breast tumors. We have developed a real-time quantitative reverse transcription-PCR assay based on TaqMan fluorescence methodology to quantify the MYC mRNA copy number. We validated the method on a large series of breast tumors. MYC Gene Overexpression was observed in 29 of 134 (22%) breast tumor RNAs, ranging from 3.2 to 19 times the level in normal breast tissues. These data imply that dysregulated MYC Gene expression is potentially involved in the pathoGenesis of breast cancer, especially by favoring local cell proliferation. We also found that MYC Gene Overexpression was rarely due to an increased MYC Gene copy number in breast cancer. This new, simple, rapid, and semiautomated method will be useful for screening cancer patients for MYC Overexpression and will prove a powerful tool in large, randomized, prospective, cooperative group trials and in the MYC -based therapy project.
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quantitation of myc Gene expression in sporadic breast tumors with a real time reverse transcription pcr assay
Cancer Research, 1999Co-Authors: Ivan Bieche, Ingrid Laurendeau, Sengul Tozlu, Martine Olivi, Dominique Vidaud, Rosette Lidereau, Michel VidaudAbstract:MYC Gene Overexpression was identified recently as a downstream step at the end of the Wnt/APC/beta-catenin pathway dysregulation observed in colorectal cancer (T-C. He et al., Science (Washington DC), 281: 1509-1512, 1998). It thus appears that an excess of c-myc protein is a primary cause of numerous cancers. In breast cancer, MYC has been studied mostly at the DNA level because of the poor quality of available antibodies against the protein product. The renewed interest in MYC calls for a sensitive and accurate method for analyzing MYC Overexpression in breast tumors. We have developed a real-time quantitative reverse transcription-PCR assay based on TaqMan fluorescence methodology to quantify the MYC mRNA copy number. We validated the method on a large series of breast tumors. MYC Gene Overexpression was observed in 29 of 134 (22%) breast tumor RNAs, ranging from 3.2 to 19 times the level in normal breast tissues. These data imply that dysregulated MYC Gene expression is potentially involved in the pathoGenesis of breast cancer, especially by favoring local cell proliferation. We also found that MYC Gene Overexpression was rarely due to an increased MYC Gene copy number in breast cancer. This new, simple, rapid, and semiautomated method will be useful for screening cancer patients for MYC Overexpression and will prove a powerful tool in large, randomized, prospective, cooperative group trials and in the MYC-based therapy project.
K V Kiselev - One of the best experts on this subject based on the ideXlab platform.
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effect of spruce pjsts1a pjsts2 or pjsts3 Gene Overexpression on stilbene biosynthesis in callus cultures of vitis amurensis rupr
Biotechnology and Applied Biochemistry, 2020Co-Authors: Andrey R Suprun, Zlata V Ogneva, A S Dubrovina, K V KiselevAbstract:Stilbenes are natural compounds protecting plants against microbial pathogens and known to possess valuable biologically active properties. In the present study, we established transgenic grapevine callus cell cultures overexpressing three stilbene synthase (STS) Genes of spruce Picea jezoensis PjSTS1a, PjSTS2, and PjSTS3. Transformation of Vitis amurensis calli with the PjSTS1a, PjSTS2, and PjSTS3 Genes significantly increased total content of stilbenes in 3.6-6, 2.5-2.9, and 4.1-16.1 times, respectively, in comparison with the control calli. The most pronounced positive effect on the accumulation of stilbenes was observed for the PjSTS3-overexpressing calli where the total content of stilbenes was increased up to 3.1 mg/g DW, and the stilbene production reached 25.4 mg/L. These values were higher than those achieved for the grapevine callus cell cultures overexpressing three STS Genes from V. amurensis. Thus, transformation of grapevine cell cultures with spruce STS Genes with a relatively low degree of homology to the endogenous VaSTSs is a more effective strategy for induction of plant secondary metabolite biosynthesis than using the grapevine Genes for the Overexpression experiments.
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vacpk20 Gene Overexpression significantly increased resveratrol content and expression of stilbene synthase Genes in cell cultures of vitis amurensis rupr
Applied Microbiology and Biotechnology, 2014Co-Authors: O A Aleynovashumakova, A S Dubrovina, K V Kiselev, A Y Manyakhin, Y A KaretinAbstract:Resveratrol, a naturally occurring plant phenol, has been reported to exhibit a wide range of valuable biological and pharmacological properties. In the present investigation, we show that transformation of a Vitis amurensis Rupr. cell suspension with the Gene VaCPK20 for a calcium-dependent protein kinase (CDPK) under the control of double CaMV 35S promoter increased resveratrol production in five independently transformed cell lines in 9-68 times compared with control cells. The VaCPK20-transformed calli were capable of producing 0.04-0.42 % dry wt. of resveratrol, while the control calli produced up to 0.008 % dry wt. of resveratrol Also, we characterized expression of stilbene synthase (STS) Genes in the five VaCPK20-transgenic cell lines of V. amurensis. In all VaCPK20-transgenic cell lines, expression of VaSTS7 increased; while expression of VaSTS1 decreased. We suggest that transformation of V. amurensis calli with the VaCPK20 Gene induced resveratrol accumulation via enhancement of expression of the VaSTS7 Gene involved in resveratrol biosynthesis. The obtained data first demonstrate that Overexpression of a CDPK Gene resulted in increased accumulation of a stilbenoid phytoalexine in transgenic plant cells. We propose that the VaCPK20 Gene could play an important role in the regulation of resveratrol biosynthesis in grape cells.
Ivan Bieche - One of the best experts on this subject based on the ideXlab platform.
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quantitation of myc Gene expression in sporadic breast tumors with a real time reverse transcription pcr assay
Cancer Research, 1999Co-Authors: Ivan Bieche, Ingrid Laurendeau, Sengul Tozlu, Martine Olivi, Dominique Vidaud, Rosette Lidereau, Michel VidaudAbstract:MYC Gene Overexpression was identified recently as a downstream step at the end of the Wnt/APC/β-catenin pathway dysregulation observed in colorectal cancer (T-C. He et al. , Science (Washington DC), 281: 1509–1512, 1998). It thus appears that an excess of c-myc protein is a primary cause of numerous cancers. In breast cancer, MYC has been studied mostly at the DNA level because of the poor quality of available antibodies against the protein product. The renewed interest in MYC calls for a sensitive and accurate method for analyzing MYC Overexpression in breast tumors. We have developed a real-time quantitative reverse transcription-PCR assay based on TaqMan fluorescence methodology to quantify the MYC mRNA copy number. We validated the method on a large series of breast tumors. MYC Gene Overexpression was observed in 29 of 134 (22%) breast tumor RNAs, ranging from 3.2 to 19 times the level in normal breast tissues. These data imply that dysregulated MYC Gene expression is potentially involved in the pathoGenesis of breast cancer, especially by favoring local cell proliferation. We also found that MYC Gene Overexpression was rarely due to an increased MYC Gene copy number in breast cancer. This new, simple, rapid, and semiautomated method will be useful for screening cancer patients for MYC Overexpression and will prove a powerful tool in large, randomized, prospective, cooperative group trials and in the MYC -based therapy project.
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quantitation of myc Gene expression in sporadic breast tumors with a real time reverse transcription pcr assay
Cancer Research, 1999Co-Authors: Ivan Bieche, Ingrid Laurendeau, Sengul Tozlu, Martine Olivi, Dominique Vidaud, Rosette Lidereau, Michel VidaudAbstract:MYC Gene Overexpression was identified recently as a downstream step at the end of the Wnt/APC/beta-catenin pathway dysregulation observed in colorectal cancer (T-C. He et al., Science (Washington DC), 281: 1509-1512, 1998). It thus appears that an excess of c-myc protein is a primary cause of numerous cancers. In breast cancer, MYC has been studied mostly at the DNA level because of the poor quality of available antibodies against the protein product. The renewed interest in MYC calls for a sensitive and accurate method for analyzing MYC Overexpression in breast tumors. We have developed a real-time quantitative reverse transcription-PCR assay based on TaqMan fluorescence methodology to quantify the MYC mRNA copy number. We validated the method on a large series of breast tumors. MYC Gene Overexpression was observed in 29 of 134 (22%) breast tumor RNAs, ranging from 3.2 to 19 times the level in normal breast tissues. These data imply that dysregulated MYC Gene expression is potentially involved in the pathoGenesis of breast cancer, especially by favoring local cell proliferation. We also found that MYC Gene Overexpression was rarely due to an increased MYC Gene copy number in breast cancer. This new, simple, rapid, and semiautomated method will be useful for screening cancer patients for MYC Overexpression and will prove a powerful tool in large, randomized, prospective, cooperative group trials and in the MYC-based therapy project.
C. Figarella - One of the best experts on this subject based on the ideXlab platform.
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Overexpression of the reg Gene in non obese diabetic mouse pancreas during active diabetoGenesis is restricted to exocrine tissue
Journal of Histochemistry and Cytochemistry, 2000Co-Authors: D. Sanchez, N. Baeza, Richard Blouin, Christiane Devaux, Gilles Grondin, Kamel Mabrouk, Odette Guy Crotte, C. FigarellaAbstract:We demonstrated pancreatic reg Gene Overexpression in non-obese diabetic (NOD) mice during active diabetoGenesis. The aim of this study was to determine in which part of the pancreas (endocrine and/or exocrine) the Gene(s) and the protein(s) were expressed and if their localization changed with progression of the disease. In situ hybridization analysis and immunocytochemical studies were carried out on pancreas of female and male NOD mice. Both develop insulitis but diabetes develops only in females and in males only when treated by cyclophosphamide. Our results show that whatever the age, sex, and presence of insulitis and/or diabetes, the expression of reg mRNAs and of the corresponding protein(s) was restricted to exocrine tissue. Moreover, reg remains localized in acinar cells in the two opposite situations of (a) cyclophosphamide-treated males in a prediabetic stage presenting a high level of both insulin and reg mRNAs, and (b) the overtly diabetic females with no insulin but a high level of reg mRNA...
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specific reg ii Gene Overexpression in the non obese diabetic mouse pancreas during active diabetoGenesis
FEBS Letters, 1997Co-Authors: N. Baeza, D. Sanchez, Bernard Vialettes, C. FigarellaAbstract:The reg Gene, previously described in islets of 90% pancreatectomized and nicotinamide-treated rats, has been shown to be expressed in many pharmacological or surgical animal models of beta cell reGeneration. We have studied the non-obese diabetic (NOD) mouse, which represents a good model of spontaneous autoimmune diabetes in which reGenerative processes have recently been demonstrated. Two reg Genes have been described in the mouse genome, both recognized by the human reg cDNA. In a previous work, using the human probe, we have demonstrated a strong correlation between pancreatic reg Gene expression and the likelihood of developing diabetes. In the present study, we have examined the respective levels of both mouse reg I and reg II mRNA in the NOD mouse pancreas using their specific cDNA probes. We found that reg II expression was specifically prevalent compared to reg I, irrespective of sex or state of the disease. Reg II mRNA was particularly increased in overtly diabetic female mice and in cyclophosphamide-treated male mice. These data underline the need to study separately the reg Genes using specific probes and show that both reg Genes are subjected to various regulations, strongly suggesting that their physiological functions may be different.
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pancreatic reGenerating Gene Overexpression in the nonobese diabetic mouse during active diabetoGenesis
Diabetes, 1996Co-Authors: N. Baeza, C. Figarella, Christine Moriscot, Wanda Renaud, Hiroshi Okamoto, Bernard VialettesAbstract:The reg Gene has previously been shown to be associated with reGeneration of pancreatic islets. Strategies for influencing the replication and the growth of the β-cell mass may be important for prevention and/or treatment of type I diabetes. In this study, we have examined the level of reg Gene expression at various degrees of diabetoGenesis in the pancreas of the NOD mouse (male, female, and cyclophosphamide-treated male) using both human reg cDNA as the probe and dot blot analysis. The expression of the reg Gene was found to be significantly increased in female mice compared with male mice, and in both cases, the expression level was not influenced by age. Nondiabetic female mice have a significantly higher expression of the Gene than diabetic female mice, and there was a positive correlation between the age of diabetes onset and the reg mRNA level. In addition, Overexpression of the reg Gene was found in male mice treated by cyclophosphamide, an agent known to be a potent inducer of diabetes in male NOD mice. None of these results were found in the diabetes-resistant control OF1 mice, in which pancreatic reg Gene expression did not differ between female and male mice treated or untreated with cyclophosphamide. All of these data suggest that there is a strong correlation between reg Gene expression in the pancreas of the NOD mouse and the likelihood of developing diabetes.
Audrey P Gasch - One of the best experts on this subject based on the ideXlab platform.
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natural variation in the consequences of Gene Overexpression and its implications for evolutionary trajectories
eLife, 2021Co-Authors: Deelegant Robinson, Michael Place, James Hose, Adam Jochem, Audrey P GaschAbstract:Copy number variation through Gene or chromosome amplification provides a route for rapid phenotypic variation and supports the long-term evolution of Gene functions. Although the evolutionary importance of copy-number variation is known, little is understood about how Genetic background influences its tolerance. Here, we measured fitness costs of over 4000 overexpressed Genes in 15 Saccharomyces cerevisiae strains representing different lineages, to explore natural variation in tolerating Gene Overexpression (OE). Strain-specific effects dominated the fitness costs of Gene OE. We report global differences in the consequences of Gene OE, independent of the amplified Gene, as well as Gene-specific effects that were dependent on the Genetic background. Natural variation in the response to Gene OE could be explained by several models, including strain-specific physiological differences, resource limitations, and regulatory sensitivities. This work provides new insight on how Genetic background influences tolerance to Gene amplification and the evolutionary trajectories accessible to different backgrounds.
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natural variation in the consequences of Gene Overexpression and its implications for evolutionary trajectories
bioRxiv, 2021Co-Authors: Deelegant Robinson, Michael Place, James Hose, Adam Jochem, Audrey P GaschAbstract:Abstract Copy number variation (CNV) through Gene or chromosome amplification provides a route for rapid phenotypic variation and supports long-term evolution of Gene functions. Although the evolutionary importance of CNV is known, little is understood about how Genetic background influences CNV tolerance. Here, we measured fitness costs of over 4,000 over-expressed Genes in 15 Saccharomyces cerevisiae strains representing different lineages, to explore natural variation in tolerating Gene Overexpression (OE). Strain-specific effects dominated the fitness costs of Gene OE. We report global differences in the consequences of Gene OE, independent of the amplified Gene, as well as Gene-specific effects that were dependent on the Genetic background. Natural variation in the response to Gene OE could be explained by several models, including strain-specific physiological differences, resource limitations, and regulatory sensitivities. This work provides new insight on how Genetic background influences tolerance to Gene amplification and the evolutionary trajectories accessible to different backgrounds.
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leveraging Genetic background effects in saccharomyces cerevisiae to improve lignocellulosic hydrolysate tolerance
Applied and Environmental Microbiology, 2016Co-Authors: Maria Sardi, Nikolay Rovinskiy, Yaoping Zhang, Audrey P GaschAbstract:ABSTRACT A major obstacle to sustainable lignocellulosic biofuel production is microbe inhibition by the combinatorial stresses in pretreated plant hydrolysate. Chemical biomass pretreatment releases a suite of toxins that interact with other stressors, including high osmolarity and temperature, which together can have poorly understood synergistic effects on cells. Improving tolerance in industrial strains has been hindered, in part because the mechanisms of tolerance reported in the literature often fail to recapitulate in other strain backgrounds. Here, we explored and then exploited variations in stress tolerance, toxin-induced transcriptomic responses, and fitness effects of Gene Overexpression in different Saccharomyces cerevisiae (yeast) strains to identify Genes and processes linked to tolerance of hydrolysate stressors. Using six different S. cerevisiae strains that together maximized phenotypic and Genetic diversity, first we explored transcriptomic differences between resistant and sensitive strains to identify common and strain-specific responses. This comparative analysis implicated primary cellular targets of hydrolysate toxins, secondary effects of defective defense strategies, and mechanisms of tolerance. Dissecting the responses to individual hydrolysate components across strains pointed to synergistic interactions between osmolarity, pH, hydrolysate toxins, and nutrient composition. By characterizing the effects of high-copy Gene Overexpression in three different strains, we revealed the breadth of the background-specific effects of Gene fitness contributions in synthetic hydrolysate. Our approach identified new Genes for engineering improved stress tolerance in diverse strains while illuminating the effects of Genetic background on molecular mechanisms. IMPORTANCE Recent studies on natural variation within Saccharomyces cerevisiae have uncovered substantial phenotypic diversity. Here, we took advantage of this diversity, using it as a tool to infer the effects of combinatorial stress found in lignocellulosic hydrolysate. By comparing sensitive and tolerant strains, we implicated primary cellular targets of hydrolysate toxins and elucidated the physiological states of cells when exposed to this stress. We also explored the strain-specific effects of Gene Overexpression to further identify strain-specific responses to hydrolysate stresses and to identify Genes that improve hydrolysate tolerance independent of strain background. This study underscores the importance of studying multiple strains to understand the effects of hydrolysate stress and provides a method to find Genes that improve tolerance across strain backgrounds.