Cardiac overexpression of intact p300 promoted progressive LV dilation and diminished systolic function after myocardial infarction in adult mice, which required histone acetyltransferase activity.
Does cardiac overexpression of p300 and its histone acetyltransferase activity promote left ventricular remodeling after myocardial infarction in adult mice?
Histone acetyltransferase activity of p300 is required for the promotion of left ventricular remodeling and dysfunction after myocardial infarction in vivo.
BACKGROUND: Left ventricular (LV) remodeling after myocardial infarction is associated with hypertrophy of surviving myocytes and represents a major process that leads to heart failure. One of the intrinsic histone acetyltransferases, p300, serves as a coactivator of hypertrophy-responsive transcriptional factors such as a cardiac zinc finger protein GATA-4 and is involved in its hypertrophic stimulus-induced acetylation and DNA binding. However, the role of p300-histone acetyltransferase activity in LV remodeling after myocardial infarction in vivo is unknown. METHODS AND RESULTS: To solve this problem, we have generated transgenic mice overexpressing intact p300 or mutant p300 in the heart. As the result of its 2-amino acid substitution in the p300-histone acetyltransferase domain, this mutant lost its histone acetyltransferase activity and was unable to activate GATA-4-dependent transcription. The two kinds of transgenic mice and the wild-type mice were subjected to myocardial infarction or sham operation at the age of 12 weeks. Intact p300 transgenic mice showed significantly more progressive LV dilation and diminished systolic function after myocardial infarction than wild-type mice, whereas mutant p300 transgenic mice did not show this. CONCLUSIONS: These findings demonstrate that cardiac overexpression of p300 promotes LV remodeling after myocardial infarction in adult mice in vivo and that histone acetyltransferase activity of p300 is required for these processes.
Miyamoto et al. (Mon,) conducted a other in Myocardial infarction and left ventricular remodeling. Overexpression of intact p300 vs. Mutant p300 transgenic mice and wild-type mice was evaluated on Left ventricular dilation and systolic function after myocardial infarction. Cardiac overexpression of intact p300 promoted progressive LV dilation and diminished systolic function after myocardial infarction in adult mice, which required histone acetyltransferase activity.