组蛋白H3K9ac乙酰化与H3K9me3甲基化修饰对小鼠心脏发育的交互调控作用

Interactive regulatory effect of histone H3K9ac acetylation and histone H3K9me3 methylation on cardiomyogenesis in mice

摘要:

目的 探讨组蛋白乙酰化和甲基化修饰对心脏发育的交互调控作用，为先天性心脏病的防治提供新的理论基础。方法 将24只昆明孕小鼠随机分为胚胎14.5 d（ED 14.5）组、胚胎16.5 d（ED 16.5）组、新生0.5 d（PND 0.5）组及新生7 d（PND 7）组，采集各组胎鼠及新生小鼠心脏，每组检测标本数为6。运用比色法检测心肌组织组蛋白乙酰化酶（HATs）及组蛋白甲基转移酶（HMTs）活性；Western blot法检测心肌组织组蛋白H3第9位赖氨酸乙酰化（H3K9ac）及组蛋白H3第9位赖氨酸三甲基化（H3K9me3）表达水平。结果 比色法结果表明：HATs和HMTs活性在出生前均呈现高表达，出生后均呈现低表达；且PND 0.5和PND7时小鼠心肌组织HATs活性与ED 14.5时相比，以及PND 7时小鼠心肌组织HATs活性与ED 16.5时相比差异均有统计学意义（P < 0.05）；小鼠心肌组织HMTs活性在PND 7时与ED 14.5和ED 16.5时相比差异有统计学意义（P < 0.05）。Western blot结果显示：组蛋白H3K9ac和H3K9me3在出生前呈现高表达，出生后呈现低表达，且PND 0.5和PND 7时小鼠心肌组织组蛋白H3K9ac和H3K9me3分别与ED 14.5和ED 16.5时相比差异均有统计学意义（P < 0.05）。结论 在心脏发育过程中HATs、HMTs及组蛋白H3K9ac、H3K9me3呈现动态表达，提示HATs和HMTs介导的组蛋白H3K9ac乙酰化及H3K9me3甲基化修饰在心脏发育过程中可能发挥了交互调控作用。

Abstract:

Objective To study the interactive regulatory effect of histone acetylation and methylation on cardiomyogenesis, and to provide a theoretical basis for the prevention and treatment of congenital heart disease. Methods A total of 24 Kunming mice were randomly divided into embryo day 14.5 (ED 14.5) group, embryo day 16.5 (ED 16.5) group, postnatal day 0.5 (PND 0.5) group, and postnatal day 7 (PND 7) group, with 6 mice in each group, and the heart tissue of fetal and neonatal mice was collected. Colorimetry was used to measure the activities of histone acetylases (HATs) and histone methyltransferases (HMTs) in the myocardium. Western blot was used to measure the expression of H3K9ac and H3K9me3 in the myocardium. Results Colorimetry showed that the activities of HATs and HMTs were higher before birth and were lower after birth. There was a significant difference in the activity of HATs in the myocardium between the PND 0.5 and PND 7 groups and the ED 14.5 group (P < 0.05), as well as between the PND 7 group and the ED 16.5 group (P < 0.05). There was also a significant difference in the activity of HMTs in the myocardium between the PND 7 group and the ED 14.5 and ED 16.5 groups (P < 0.05). Western blot showed higher expression of H3K9ac and H3K9me3 before birth and lower expression of H3K9ac and H3K9me3 after birth, and there were significant differences in the expression H3K9ac and H3K9me3 in the myocardium between the PND 0.5 and PND 7 groups and the ED 14.5 and ED 16.5 groups (P < 0.05). Conclusions The dynamic expression of HATs, HMTs, H3K9ac, and H3K9me3 is observed during cardiomyogenesis, suggesting that histone H3K9ac acetylation and histone H3K9me3 methylation mediated by HATs and HMTs may play a role in interactive regulation during cardiomyogenesis.