Project description:Identfification of MEF2A target genes using ChIP-exo in skeletla muscle and primary cardiomyocytes. Identfification of MEF2A target genes using ChIP-exo and RNA-seq in skeletal muscle and primary cardiomyocytes. MEF2 plays a profound role in the regulation of transcription in cardiac and skeletal muscle lineages. To define the overlapping and unique MEF2A genomic targets, we utilized ChIP-exo analysis of cardiomyocytes and skeletal myoblasts. Of the 2783 and 1648 MEF2A binding peaks in skeletal myoblasts and cardiomyocytes, respectively, 294 common binding sites were identified. Genomic targets were compared to differentially expressed genes in RNA-seq analysis of MEF2A depleted myogenic cells. MEF2A target genes were identified in 48 hr DM C2C12 myoblasts cells and primary cardiomyocytes using ChIP-exo. Binding profiles on MEF2A in each cell type were compared. Cross sectional-analysis between ChIP-exo identified targets and RNA-seq analysis of MEF2A deplted myoblasts was also done.
Project description:Identfification of MEF2A target genes using ChIP-exo and RNA-seq in skeletal muscle and primary cardiomyocytes. MEF2 plays a profound role in the regulation of transcription in cardiac and skeletal muscle lineages. To define the overlapping and unique MEF2A genomic targets, we utilized ChIP-exo analysis of cardiomyocytes and skeletal myoblasts. Of the 2783 and 1648 MEF2A binding peaks in skeletal myoblasts and cardiomyocytes, respectively, 294 common binding sites were identified. Genomic targets were compared to differentially expressed genes in RNA-seq analysis of MEF2A depleted myogenic cells. The effect of MEF2A gene silencing on gene expression in myoblasts was assessed at 48 hr DM. Up and downregulated genes were then compared to MEF2A target genes identified in ChIP-exo analysis of 48 hr DM C2C12 myoblasts cells and primary cardiomyocytes.
Project description:In this study, we used ChIP-seq to map Six4 binding profile in different C2C12 cell lines 24 hours after differentiation (T24). We performed ChIP-seq using two different antibodies: anti-Flag antibody in Flag-Six4 C2C12 cell line or in parental C2C12 cells; a custom-made anti-Six4 antibody in shNS C2C12 cell line (a control cell line) or shSix4 C2C12 (C2C12 with stable Six4 knockdown using short hairpin RNA). We also performed ChIP-seq in parental C2C12 cells using normal rabbit IgG. We were able to identify Six4-bound loci in C2C12 T24 that were recognized by two different antibodies and showed a decrease in peak intensity in shSix4 C2C12 compared to shNS C2C12 cells. We established a C2C12 cell line with stable Six4 knockdown by short hairpin RNA (shSix4) vs. a control cell line (shNS). We also established a C2C12 cell line with stable expression of Flag-Six4-myc by infection of retroviruses expressing pBABE-Flag-Six4-myc (Flag-Six4 C2C12) vs. parental C2C12. We differentiate these cells for 24 hours before using them for ChIP-seq.
Project description:In this study, we used C3H/10T1/2 cells, a well known model of myogenic conversion, to study the effect of Six4 knockdown on the expression of genes during fibroblasts to myocytes conversion induced by ectopic expression of MyoD We established C3H/10T1/2 cell line with stable Six4 knockdown by short hairpin RNA (shSix4) vs a control cell line (shLuc) and converted these cells into myogenic lineage by retroviral transduction of plasmid encoding Flag-MyoD-myc (pBABE-MyoD) or empty plasmid (pBABE). Cells were then induced to differentiate for 24 hours before RNA extraction.
Project description:microRNAs (miRNAs) are non-coding RNAs that regulate gene expression post-transcriptionally, and mounting evidences support the prevalence and functional significance of their interplay with transcription factors (TFs). Here we describe the identification of a regulatory circuit between muscle miRNAs (miR-1, miR-133 and miR-206) and Yin Yang 1 (YY1), an epigenetic repressor of skeletal myogenesis. Genome-wide identification of potential YY1 down-stream targets by combining computational prediction with expression profiling data reveals a large number of putative miRNA targets of YY1 during skeletal myoblasts differentiation into myotubes with muscle miRs rank on top of the list. Murine skeletal muscle cells (C2C12 cells) were differentiated for 0, 1 or 3 days. Total RNAs were isolated from the cells and used for array profiling of miRNA expression.
Project description:Six1, Six4 and Myogenin are transcription factors that are known to be required for skeletal myogenesis. Currently, very little is known about the genes targeted by Six1 and Six4. Gene expression profiling when one or both transcription factors were knock-down by siRNA was performed to identify genes affected by their absence. We also hypothesized that Six1 and Six4 can work in cooperation with the myogenic regulatory factor (MRFs) family of transcription factors, such as Myogenin. Therefore, we performed the same type of experiment where the myogenin was knocked-down by siRNA to identify genes that are possibly regulated by the Six1 or Six4 in conjunction with Myogenin. C2C12 Myoblasts were transfected with siRNA against Six1, Six4, Six1 with Six4, Myogenin, or control 24h before start of differentiation. The cells were allowed to differentiate in differentiation medium for 24h and were harvested for gene expression profiling. Four replicates per siRNA were performed.
Project description:In this study, the C2C12 cell line, a model used to study myogenesis and regeneration, was allowed to differentiate from myoblast precursor cells to myotubes. Cells were harvested at 3 different timepoints to perform ChIP-on-Chip of Six1, which is a key muscle regulator. We identified global loci bound by Six1 during skeletal myoblast differentiation. C2C12 Myoblasts were allowed to differentiate into myotubes. Cells at three timepoints were harvested for ChIP-on-Chip, including myoblasts stage, 24h after differentiation and myotubes (96h after differentiation). Myotubes were detached from the undifferentiated myoblast reserve cells using diluted trypsin. 3 independent biological replicates were used for each time point experiment. A microarray set counts 3 arrays (Custom Arrays A, B and C) for a total of approximately 2.9 million probes.
Project description:Nrf2 (NF-E2-related-factor-2) contributes to the maintenance of glucose homeostasis in vivo. Nrf2 suppresses blood glucose levels by protecting pancreatic β-cells from oxidative stress and improving peripheral tissue glucose utilization. To elucidate the molecular mechanisms by which Nrf2 contributes to the maintenance of glucose homeostasis, we generated skeletal muscle (SkM)-specific Keap1-knockout (Keap1MuKO) mice that express abundant Nrf2 in SkM and then examined Nrf2-target gene expression in this tissue. In Keap1MuKO mice, blood glucose levels were significantly downregulated, and the levels of glycogen branching enzyme (Gbe1) mRNA, along with those of glycogen branching enzyme (GBE) protein, were significantly upregulated in mouse SkM. Consistent with this result, chemical Nrf2-inducers promoted Gbe1 mRNA expression in both mouse SkM and C2C12 myotubes. Chromatin-immunoprecipitation analysis demonstrated that Nrf2 binds the Gbe1 upstream promoter regions. In Keap1MuKO mice, muscle glycogen content was strongly reduced, and forced GBE expression in C2C12 myotubes promoted glucose uptake. Therefore, our results demonstrate that Nrf2-induction in SkM increases GBE expression and reduces muscle glycogen content, resulting in improved glucose tolerance. Chromatin occupancy of Nrf2 under CDDO-Im-treated condition were generated by deep sequencing, in dupliplicate
Project description:By applying ChIP-seq, we generated genome-wide maps of YY1 in skeletal myoblasts and myotubes. We found that YY1 binds to 1820 confident target with a large portion residing in the intergenic regions. In addition, YY1 was found to activate many loci, and there is no significant overlap between YY1 and Ezh2 targets, suggensting a Ezh2-independent manner. Further detailed study revealed that YY1 can regulate some lincRNAs which are fucntional in skeletal myogenesis. In this study, we identified a YY1-Yam-1-miR-715 (TF-lincRNA-miRNA) regulatory curcuit in myogensis. Examination of YY1 targets in myoblast versus myotubes