Project description:We identified LRRFIP2 as a novel negative cofactor of HIF-1 Indeed, we showed that the absence of Lrrfip2 expression in a mouse KI model leads to an increase in many HIF-1 target genes including AldoC, Bnip3 and Ndufa4l2 in embryonic CM during development. Overactivation of HIF-1 in Lrrfip2-null mice led to structural and functional mitochondrial dysfunction, decreased ROS levels and ultimately early CM maturation.
Project description:We performed time-dependent, genome-wide analysis to explore gene expression profiles during in vitro cardiogenesis from embryonic stem cells to cardiac progenitor cells. Total RNA was extracted from undifferentiated stem cells, early mesodermal cells, cardiac mesodermal cells and cardiac progenitor cells. As a result of cluster analysis, Cited gene family was considered as candidate genes in cardiogenesis. Cited4 gene expression was specific for early cardiogenesis and Cited4 functioned as a cell cycle controling factor for early cardiac progenitor cells.
Project description:We performed time-dependent, genome-wide analysis to explore gene expression profiles during in vitro cardiogenesis from embryonic stem cells to cardiac progenitor cells. Total RNA was extracted from undifferentiated stem cells, early mesodermal cells, cardiac mesodermal cells and cardiac progenitor cells. As a result of cluster analysis, Cited gene family was considered as candidate genes in cardiogenesis. Cited4 gene expression was specific for early cardiogenesis and Cited4 functioned as a cell cycle controling factor for early cardiac progenitor cells. Embryoid body was formed as in vitro cardiogenesis. Total RNA was extracted from Rex1-positive undifferentiated stem cells at day 0, Bra-positive early mesodermal cells at day 4.5, Flk1-positive cardiac mesodermal cells at day 4.5 and Nkx2.5-positive cardiac progenitor cells at day 7.5.
Project description:Mammalian heart development is built on highly conserved molecular mechanisms with polygenetic perturbations resulting in a spectrum of congenital heart diseases (CHD). However, the transcriptional landscape of cardiogenic ontogeny that regulates proper cardiogenesis remains largely based on candidate-gene approaches. Herein, we designed a time-course transcriptome analysis to investigate the genome-wide expression profile of innate murine cardiogenesis ranging from embryonic stem cells to adult cardiac structures. This comprehensive analysis generated temporal and spatial expression profiles, prioritized stage-specific gene functions, and mapped the dynamic transcriptome of cardiogenesis to curated pathways. Reconciling the bioinformatics of the congenital heart disease interactome, we deconstructed disease-centric regulatory networks encoded within this cardiogenic atlas to reveal stage-specific developmental disturbances clustered on epithelial-to-mesenchymal transition (EMT), BMP regulation, NF-AT signaling, TGFb-dependent induction, and Notch signaling. Therefore, this cardiogenic transcriptional landscape defines the time-dependent expression of cardiac ontogeny and prioritizes regulatory networks at the interface between health and disease. To interrogate the temporal and spatial expression profiles across the entire genome during mammalian heart development, we designed a time-course microarray experiment using the mouse model at defined stages of cardiogenesis, starting with embryonic stem cells (ESC, R1 stem cell line), early embryonic developmental stages: E7.5 whole embryos, E8.5 heart tubes, left and right ventricle tissues at E9.5, E12.5, E14.5, E18.5 to 3 days after birth (D3) and adult heart (Figure 1A). At each time point, microarray experiments were performed on triplicate biological samples. Starting at E9.5, tissue samples from left ventricles (LV) and right ventricles (RV) were microdissected for RNA purification and microarray analysis to determine spatially differential gene expression between LV and RV during heart development.
Project description:Mammalian heart development is built on highly conserved molecular mechanisms with polygenetic perturbations resulting in a spectrum of congenital heart diseases (CHD). However, the transcriptional landscape of cardiogenic ontogeny that regulates proper cardiogenesis remains largely based on candidate-gene approaches. Herein, we designed a time-course transcriptome analysis to investigate the genome-wide expression profile of innate murine cardiogenesis ranging from embryonic stem cells to adult cardiac structures. This comprehensive analysis generated temporal and spatial expression profiles, prioritized stage-specific gene functions, and mapped the dynamic transcriptome of cardiogenesis to curated pathways. Reconciling the bioinformatics of the congenital heart disease interactome, we deconstructed disease-centric regulatory networks encoded within this cardiogenic atlas to reveal stage-specific developmental disturbances clustered on epithelial-to-mesenchymal transition (EMT), BMP regulation, NF-AT signaling, TGFb-dependent induction, and Notch signaling. Therefore, this cardiogenic transcriptional landscape defines the time-dependent expression of cardiac ontogeny and prioritizes regulatory networks at the interface between health and disease.
Project description:During heart development, an evolutionarily conserved network of cardiac transcription factors collaborate to define the precise timing and location of cardiac progenitor specification. Accumulating evidence suggests that cardiac progenitor specification is subject to transcriptional control beyond the level of transcription initiation. The PAF1C component Rtf1 is a multifunctional transcription regulatory protein that modulates pausing and elongation of RNA Pol II, as well as histone epigenetic modifications. By transient knockdown and CRISPR mutagenesis, we found that Rtf1 is essential for cardiogenesis and that without Rtf1 activity, cardiac progenitors arrest in an immature state. This role in early cardiogenesis was evolutionarily conserved between fish and mammals. We also found that Rtf1's Plus3 domain, which confers interaction with the pausing/elongation factor Spt5, was required for Rtf1's ability to support cardiac progenitor formation, while other regions of the protein were dispensable. We examined the occupancy of RNA Pol II at cardiac genes in rtf1 morphants using ChIP-seq and found that Pol II signals at the TSS of genes was reduced, suggesting a reduction in transcriptional pausing. Intriguingly, pharmacological or morpholino antisense reduction of pause release in rtf1 morphants and mutants restored the formation of cardiac cells and improved Pol II occupancy at the TSS of key cardiac genes. Our findings highlight the crucial role that transcriptional pausing plays in promoting normal levels of gene expression in a cardiac developmental context.