Transcriptomic and Epigenetic Signatures of Mouse Cardiac Progenitor Cells (CHARM)

Adult cardioyocytes undergo remarkable dedifferentiation and cell cycle reprogramming/reentery when cultured in mitogen-rich medium, continuously, and give rise to cardiac progenitor cells (CPCs). Using microfluidic device for single-cell capture and whole-transcriptomic amplification, we analyze the whole-genome transcriptomic profile in adult mouse cardiomyocytes (Ctl) and in their derived CPCs, and validate the gene expression by single-cell PCR and PCR array. Using two platforms for DNA methylation profiling: NimbleGen DNA methylation array and CHARM array, the whole-genome DNA methylation profile in myocytes (Ctl) and CPCs were compared and their regulations in relationship to the transcriptomics profile were analyzed. The results demonstrated remarkable molecular reprogramming pertaining to dedifferentiation, loss of cardiac contractile, structure, and function molecules, and reactivation of cell cycle and proliferation genes, significant changes in metabolisms. The reduction of cardiac function and structure genes are highly related to their hypermethylation of the promoter regions. GO and Pathway enrichment analysis revealed distinct coordianted transcriptomic and epigenetic regulation in the CPCs derived from cardiomyocytes. Genomic DNA isolated from adult mouse cardiomyocytes (Ctl) or cardiomyocyte-derived progenitor cells (CPCs) was subjected to digestion by methylcytosine-sensitive enzyme McrBC, and subsequently purification and amplification, labeling and hybridization according to NimbleGen protocol. Percentage methylation, hypermethylation or hypomethylation, and peak enrichment were assessed using CHARM protocol.