Objective     To investigate the temporal expression of GATA4 in the development process of mouse embryonic heart and elucidate the underlying mechanism of histone modification. Methods     RT-PCR was used to detect the expression of GATA4 in fetal mouse hearts from gestational age E11.5 d to postnatal 0.5 d. ChIP-QPCR was employed to the expression level of histone marker H3K9ac in GATA4 promoter region and the binding level of CBP/P300. After the cardiac progenitor cells were treated with CBP30 at different concentrations (0.5

1.0

2.0 and 4.0 μmol/L) for different time periods (6

12

24 and 48 h)

the expression levels of GATA4 mRNA and H3K9ac

and the binding level were measured again.  Results     ①The expression level of GATA4 mRNA was significantly higher at E11.5 than at E14.5 (P0.05). ChIP assay demonstrated that the expression level of H3K9ac in GATA4 promoter region was higher at E14.5 than at E11.5 (P0.05)

and the binding of CBP/P300 to GATA4 promoter region was stronger at E14.5 than at E11.5 (P0.05). ②Compared with control group

CBP30 resulted in an obvious decrease in GATA4 expression in cardiac progenitor cells (P0.05). In CBP30 treated cells group

all the tested markers above mention were decreased dramatically

compared to control group (P0.05).   Conclusion     CBP/P300 is involved in the GATA4 regulation through mediating H3K9 acetylation during the heart development in mice.