Transcriptomic Signatures of Mouse Cardiomyocyte Dedifferentiation In vitro (Affymetrix)

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. Mouse single cardiomyocytes (Ctl) and their derievd single CPCs were captured using microfluidic deviced and cDNA synthesized and amplified and labelled using NuGENE kits, and regular Affymetrix hybridization and wash protocols were used to process the mouse whole-genome array GeneChip 430 2.0.