Project description:Gata factors are amongst the genes expressed early on in the process of cardiogenesis. We used microarrays to examine the immediate early targets of Gata4 and Gata5 in the Xenopus leavis animal cap cardiogenesis model. We hope to use these data to examine the roles of Gata4 and Gata5 in cardiogenesis and also to begin to dissect out the common and distinct targets of Gata4 and Gata5. Keywords: genetic modification, gene overexpresison.
Project description:Gata factors are amongst the genes expressed early on in the process of cardiogenesis. We used microarrays to examine the immediate early targets of Gata4 and Gata5 in the Xenopus leavis animal cap cardiogenesis model. We hope to use these data to examine the roles of Gata4 and Gata5 in cardiogenesis and also to begin to dissect out the common and distinct targets of Gata4 and Gata5. Experiment Overall Design: Xenopus leavis embryos were injected at the one cell stage with dexamethasone-inducible Gata4 or Gata5 mRNA constructs (to examine endodermal and mesodermal targets) or with Gata4 in the presence of Dkk1 (to examine mesodermal targets.) Embryos were cultured to stage 9, whereupon animal caps were excised and cultured for 2.5 hours in media containing dexamethasone to induce the constructs and cycloheximide to block de novo protein synthesis and thus give only immediate early targets.
Project description:Different regions of the gastrointestinal tract have distinct digestive and absorptive functions, which may be locally disrupted by infection or autoimmune disease. Yet, the mechanisms underlying intestinal regionalization and its dysregulation in disease are not well understood. Here, we used mouse models, transcriptomics, and immune profiling to show that regional epithelial expression of the transcription factor GATA4 prevented adherent bacterial colonization and inflammation in the proximal small intestine by regulating retinol metabolism and luminal IgA. Loss of epithelial GATA4 expression increased mortality in mice infected with Citrobacter rodentium which was dependent on commensal microbiota induced immunopathology. In active celiac patients with villous atrophy, low GATA4 expression was associated with metabolic alterations, mucosal Actinobacillus, and increased IL-17 immunity. This study reveals broad impacts of GATA4-regulated intestinal regionalization and highlights an elaborate interdependence of intestinal metabolism, immunity, and microbiota in homeostasis and disease.
Project description:Gata5 efficiently promotes cardiomyocyte fate from murine ESCs.By removing serum from the culture conditions, GATA4 and GATA6 are each also able to efficiently promote cardiogenesis in ESC derivatives, with some distinctions. Thus, GATA factors can function in ESC derivatives upstream of other cardiac transcription factors to direct specification of progenitors with cardiac potential. We used microarray to compared the global gene expression of Gata5-induced cardiac cells with other growth factor directed ESC-derived cardiac cells iGata5 ESCs were induced with doxycycline at day 4 and harvested at day16 for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Gata5 efficiently promotes cardiomyocyte fate from murine ESCs.By removing serum from the culture conditions, GATA4 and GATA6 are each also able to efficiently promote cardiogenesis in ESC derivatives, with some distinctions. Thus, GATA factors can function in ESC derivatives upstream of other cardiac transcription factors to direct specification of progenitors with cardiac potential. We used microarray to compared the global gene expression of Gata5-induced cardiac cells with other growth factor directed ESC-derived cardiac cells
Project description:Dominant mutations in cardiac transcription factor genes cause human inherited congenital heart defects (CHDs), but their molecular basis is not understood. Transcription factors and Brg1/Brm-associated factor (BAF) chromatin remodeling complex interactions suggest potential mechanisms, but the role of BAF complexes in cardiogenesis is not known. Here we show that dosage of Brg1 is critical for mouse and zebrafish cardiogenesis. Disrupting the balance between Brg1 and disease-causing cardiac transcription factors, including Tbx5, Tbx20, and Nkx2-5, causes severe cardiac anomalies, revealing an essential allelic balance between Brg1 and these cardiac transcription factor genes. This suggests that relative levels of transcription factors and BAF complexes are important for heart development, which is supported by reduced occupancy of Brg1 at cardiac genes in Tbx5 haploinsufficient hearts. Our results reveal complex dosage-sensitive interdependence between transcription factors and BAF complexes, providing a potential mechanism underlying transcription factor haploinsufficiency, with implications for multigenic inheritance of CHDs. We performed transcriptional profiling of E11.5 hearts from mice heterozygous for deletions of Brg1, Tbx5, or Nkx2-5, and mice that were compound heterozygotes for Brg1 and each transcription factor gene (Tbx5 and Nkx2-5).