CXXC zinc finger protein 1 (Cfp1) controls cardiomyocyte maturation by modifying histone H3K4me3 of structural, metabolic, and contractile related genes

Cardiomyocyte maturation is the final stage of heart development, and abnormal cardiomyocyte maturation will lead to serious heart diseases. CXXC zinc finger protein 1 (Cfp1) is an important epigenetic factor, which plays an essential role in the development and maturation of multi-lineage cells, while its effect on the maturation of cardiomyocyte remains unclear. This study was performed to explore the potential role of Cfp1 in cardiomyocyte maturation of heart and the underlying mechanisms. Cardiomyocyte-specific Cfp1 knockout (Cfp1-cKO) mice died within 4 weeks of birth. Cardiomyocytes from Cfp1-cKO mice showed an inhibited maturation phenotype in structure, metabolism, contractile function, and cell cycle, accompanied by down-regulation of adult genes and up-regulation of fetal genes. In contrast, cardiomyocyte-specific Cfp1 transgenic (Cfp1-TG) mice and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) overexpressing Cfp1 showed a more mature phenotype. Mechanistically, deficiency of Cfp1 results in reduced trimethylation on lysine 4 of histone H3 (H3K4me3) modification and formation of ectopic H3K4me3. Moreover, Cfp1 deletion decreased the level of H3K4me3 modification in adult genes and increased the level of H3K4me3 modification in fetal genes. Collectively, Cfp1 modulates the expression of cardiomyocyte maturation related genes by modulating histone H3K4me3 modification, which in turn regulates cardiomyocyte maturation. This study implicates Cfp1 as an important molecule regulating cardiomyocyte maturation, and its dysfunction is strongly associated with cardiac disease. WT and Cxxc1 null hearts are collected to perform high-throughput sequencing.