Genome-wide maps of KDM5A/JARID1A/RBP2 and JARID2/JMJ in HL-1 cardiomyocytes.

We report the identification of genomic regions bound by RBP2 and JARID2 in mouse cardiomyocytes. RBP2 generates methylated lysine 4 in histone H3. Consistent with previous data, RBP2 binds at the TSS regions. However, we found that overepresentation of gene ontologies (GO) for RBP2 targets in cardiomyocytes is drastically different from those in mouse embryonic stem (ES) cells. In cardiomyocytes, there is overepresentation of genes involved in heart morphogenesis and vasculogenesis. Strikingly, we found that location of JARID2, a factor critical for ES cell function, significantly overlaps with RBP2 location in cardiomyocytes. Overall design: Examination of two homologous proteins, one of each is a histone demethylase and another is not.