Project description:Gene expression depending on artbtary Ca2+ elevation in mouse vascular endothelial cells We used microarrays to detail the global programme of gene expression relatd to putative Ca2+- increase.
Project description:Altered Ca2+ handling has both immediate physiological effects and long-term genomic effects on vascular smooth muscle function. Previously we have shown that elevation of cytoplasmic Ca2+ through voltage-dependent Ca2+ channels (VDCCs) or store-operated Ca2+ channels (SOCCs) results in phosphorylation of the Ca2+/cAMP response element binding protein (CREB) in cerebral arteries. Here we demonstrate that stimulation of these different Ca2+ influx pathways results in transcriptional activation of a distinct, yet overlapping set of genes, and that the induction of selected CRE-regulated genes is prevented by the addition of corresponding Ca2+ channel blockers. Using oligonucleotide array analysis, changes in mRNA levels were quantified following membrane depolarization with K+ or depletion of intracellular Ca2+ stores with thapsigargin in human cerebral vascular smooth muscle cells. Array results for differentially regulated genes containing a CRE were confirmed by quantitative RT-PCR, and corresponding changes in protein expression were shown by Western blot analysis and immunofluorescence. Membrane depolarization induced a transient increase in c-fos mRNA and a sustained increase in early growth response-1 (Egr-1) mRNA and protein that were inhibited by application of the VDCC blocker, nimodipine, and the SOCC inhibitor, 2-aminoethoxydiphenylborate (2-APB). Thapsigargin induced a sustained increase in c-fos mRNA and MAP kinase phosphatase-1 (MKP-1) mRNA and protein, and these effects were decreased by 2-APB but not by nimodipine. Our findings thus indicate that Ca2+ entry through VDCCs and SOCCs can differentially regulate CRE-containing genes in vascular smooth muscle and imply that signals involved in growth modulation are both temporally and spatially regulated by Ca2+. Keywords: stress response
Project description:Although differentiation of mice embryonic stem cells into vascular endothelial cells (ECs) gives a model for investigating molecular mechanisms of vascular development in vivo, temporal dynamics of gene expressions and chromatin modifications have not been studied until now. Here, we interrogated transcriptome and two histone modifications, H3K4me3 and H3K27me3, with a genome-wide scale during ECs differentiation and elucidated epigenetic switch peculiar to ECs. We find Gata2, Fli1, Sox7, and Sox18 are master regulators from genetic and epigenetic data, these genes were induced after Etv2 activation. These genes have specific histone modification pattern which is repressed by H3K27me3 modification at Flk-sorted mesoderm and changed to the bivalent (H3K4me3 and H3K27me3 both positive) state rapidly after vascular endothelial cells growth factor (VEGF) stimuli. Using a previously reported ECs differentiation model, we demonstrate that four transcription factors are critical for ECs specific gene expressions and efficient differentiation. Moreover, from knockdown experiments using si-RNA, we discovered these factors inhibited not only TGFβ signaling pathway, that is endothelial mesenchymal transition pathway, but also other near lineage commitment, including blood cells, skeletal muscle cells, vascular smooth muscle cells, and cardiomyocytes. We further identify each factor specific target genes during ECs differentiation by microarray, including both activating and repressing genes. Together, our findings from a detailed epigenetic approach provide a basic understanding temporal regulated chromatin signatures and resulting gene expression profile during ECs commitment, which is applicable to other models of differentiation and production of mature and long lasting ECs for regenerative medicine. Total 17 samples were derived from [1] ES cells, Flk-sorted mesoderm cells, and in the absense or presence of VEGF (6, 12, 24, and 48h) to determine VEGF activated genes during endothelial cells differentiation, [2] control si-RNA, si-Gata2, si-Fli1, si-Sox7, or si-Sox18 transfected cells under VEGF stimuli, [3] control si-RNA or si-Mix (si-Gata2, si-Fli1, si-Sox7, and si-Sox18) transfected cells under VEGF stimuli for the identification of each transcription factor dependent genes during endothelial cells differentiation.
Project description:Altered Ca2+ handling has both immediate physiological effects and long-term genomic effects on vascular smooth muscle function. Previously we have shown that elevation of cytoplasmic Ca2+ through voltage-dependent Ca2+ channels (VDCCs) or store-operated Ca2+ channels (SOCCs) results in phosphorylation of the Ca2+/cAMP response element binding protein (CREB) in cerebral arteries. Here we demonstrate that stimulation of these different Ca2+ influx pathways results in transcriptional activation of a distinct, yet overlapping set of genes, and that the induction of selected CRE-regulated genes is prevented by the addition of corresponding Ca2+ channel blockers. Using oligonucleotide array analysis, changes in mRNA levels were quantified following membrane depolarization with K+ or depletion of intracellular Ca2+ stores with thapsigargin in human cerebral vascular smooth muscle cells. Array results for differentially regulated genes containing a CRE were confirmed by quantitative RT-PCR, and corresponding changes in protein expression were shown by Western blot analysis and immunofluorescence. Membrane depolarization induced a transient increase in c-fos mRNA and a sustained increase in early growth response-1 (Egr-1) mRNA and protein that were inhibited by application of the VDCC blocker, nimodipine, and the SOCC inhibitor, 2-aminoethoxydiphenylborate (2-APB). Thapsigargin induced a sustained increase in c-fos mRNA and MAP kinase phosphatase-1 (MKP-1) mRNA and protein, and these effects were decreased by 2-APB but not by nimodipine. Our findings thus indicate that Ca2+ entry through VDCCs and SOCCs can differentially regulate CRE-containing genes in vascular smooth muscle and imply that signals involved in growth modulation are both temporally and spatially regulated by Ca2+. Experiment Overall Design: each of three experiments cell cultures were split three ways; one of the resulting samples was left untreated (C), another was treated with thapsigargin (TG), and the third was treated with elevated K+ (K). The resulting nine samples were used for triplicate estimates of the response of each gene to TG and K treatments. Experiment Overall Design: We tested the prospective hypothesis that genes having a CRE are differentially expressed after TG or K treatment using a permutation test: each of the 22,283 probe sets on the Affymetrix GeneChip was categorized two ways based on 1) whether or not it contains a CRE or not . Independence of CRE and threshold differential expression was rejected by Fisherâs exact test for both TG treatment ( ) and K treatment ( ). Target genes (c-fos, egr-1, and mkp-1 ) were identified based on ranking.
Project description:The Ca2+/calcineurin signaling pathway is a central conduit regulating growth, development, and virulence of fungal pathogens infecting plants and human. We have analyzed global gene expression profiles during Ca2+ treatment in the rice blast fungus, Magnaporthe oryzae. An immunosuppressive drug, FK506, and the knock-out mutant of a transcription factor, MoCRZ1, were included to analyze calcineurin- and/or CRZ1-dependent gene expression, respectively. About 1,400 genes were up or down regulated by Ca2+ treatment, while about 200 genes seemed to be up-regulated in a calcineurin/CRZ1-dependent manner. This study analyzes global gene expression dynamics during Ca2+ treatment in the rice blast fungus. We have used Agilent M. grisea 2.0 4×44K Microarrays using a single channel hybridization design. An immunosuppressive drug, FK506, and the knock out mutant of a transcription factor, MoCRZ1, were included to analyze calcineurin- and/or CRZ1-dependent gene expression, respectively. To know the time point at which the gene expression fluctuates most significantly, we treated mycelia with CaCl2 for 0, 15, 30, and 60 min. PMC1 expression level was checked by RT-PCR with the highest expression at 30 min time point. Four biological replicates of wild type and mutant mycelia were harvested after 30 min treatment with chemicals. Pairwise comparisons between Ca2+ treated vs. control and Ca2+ vs. Ca2+/FK506 in wild type (WT), and Ca2+ treated in WT vs. in mutant were conducted.
Project description:The vascular endothelium consists of endothelial cells (ECs) with important biological functions and their impairment is associated with various pathologies. ECs vary based on tissue origin and gene expression, while their functionality depends on calcium (Ca2+) signaling. In tumors, disruption of Ca2+ homeostasis after calcium electroporation (CaEP) has been shown to elicit an enhanced antitumor effect with only minimal effect on normal tissue. The difference in response to CaEP was not only observed between cancer and normal cells, but also between different endothelial cell lines. Although several vascular EC models have been developed, there is a lack of understanding regarding the molecular basis that could help explain different responses of normal tissue to CaEP. Therefore, our study aims to determine the effect of CaEP on established immortalized human EC lines EA.hy926 and HMEC-1 in terms of cytoskeleton, Ca2+ kinetics and differences in gene expression involved in regulation of Ca2+ signaling and homeostasis.
Project description:Inducible endothelial Rspo3 deletion resulted in perturbed developmental and tumor vascular remodeling. Rspo3-iECKO mice strikingly phenocopied the non-canonical WNT signaling-induced vascular defects of mice deleted for the WNT secretion factor Evi/Wls. An endothelial screen for RSPO3 and EVI/WLS co-regulated genes identified novel target genes, which could be linked to WNT/Ca2+/NFAT signaling. In summary, the study identifies endothelial RSPO3-driven non canonical WNT/Ca2+/NFAT signaling as critical maintenance pathway of the remodeling vasculature.
Project description:The Ca2+/calcineurin signaling pathway is a central conduit regulating growth, development, and virulence of fungal pathogens infecting plants and human. We have analyzed global gene expression profiles during Ca2+ treatment in the rice blast fungus, Magnaporthe oryzae. An immunosuppressive drug, FK506, and the knock-out mutant of a transcription factor, MoCRZ1, were included to analyze calcineurin- and/or CRZ1-dependent gene expression, respectively. About 1,400 genes were up or down regulated by Ca2+ treatment, while about 200 genes seemed to be up-regulated in a calcineurin/CRZ1-dependent manner.
Project description:Although differentiation of mice embryonic stem cells into vascular endothelial cells (ECs) gives a model for investigating molecular mechanisms of vascular development in vivo, temporal dynamics of gene expressions and chromatin modifications have not been studied until now. Here, we interrogated transcriptome and two histone modifications, H3K4me3 and H3K27me3, with a genome-wide scale during ECs differentiation and elucidated epigenetic switch peculiar to ECs. We find Gata2, Fli1, Sox7, and Sox18 are master regulators from genetic and epigenetic data, these genes were induced after Etv2 activation. These genes have specific histone modification pattern which is repressed by H3K27me3 modification at Flk-sorted mesoderm and changed to the bivalent (H3K4me3 and H3K27me3 both positive) state rapidly after vascular endothelial cells growth factor (VEGF) stimuli. Using a previously reported ECs differentiation model, we demonstrate that four transcription factors are critical for ECs specific gene expressions and efficient differentiation. Moreover, from knockdown experiments using si-RNA, we discovered these factors inhibited not only TGFβ signaling pathway, that is endothelial mesenchymal transition pathway, but also other near lineage commitment, including blood cells, skeletal muscle cells, vascular smooth muscle cells, and cardiomyocytes. We further identify each factor specific target genes during ECs differentiation by microarray, including both activating and repressing genes. Together, our findings from a detailed epigenetic approach provide a basic understanding temporal regulated chromatin signatures and resulting gene expression profile during ECs commitment, which is applicable to other models of differentiation and production of mature and long lasting ECs for regenerative medicine.
Project description:We have used RNA-seq to examine RNA differential expression between Procr+ and Procr- vascular endothelial cells in mouse mammary gland