G9α‐dependent histone H3K9me3 hypomethylation promotes overexpression of cardiomyogenesis‐related genes in foetal mice

Abstract

Alcohol consumption during pregnancy can cause foetal alcohol syndrome and congenital heart disease. Nonetheless, the underlying mechanism of alcohol‐induced cardiac dysplasia remains unknown. We previously reported that alcohol exposure during pregnancy can cause abnormal expression of cardiomyogenesis‐related genes, and histone H3K9me3 hypomethylation was observed in alcohol‐treated foetal mouse heart. Hence, an imbalance in histone methylation may be involved in alcohol‐induced cardiac dysplasia. In this study, we investigated the involvement of G9α histone methyltransferase in alcohol‐induced cardiac dysplasia in vivo and in vitro using heart tissues of foetal mice and primary cardiomyocytes of neonatal mice. Western blotting revealed that alcohol caused histone H3K9me3 hypomethylation by altering G9α histone methyltransferase expression in cardiomyocytes. Moreover, overexpression of cardiomyogenesis‐related genes (MEF2C, Cx43, ANP and β‐MHC) was observed in alcohol‐exposed foetal mouse heart. Additionally, we demonstrated that G9α histone methyltransferase directly interacted with histone H3K9me3 and altered its methylation. Notably, alcohol did not down‐regulate H3K9me3 methylation after G9α suppression by short hairpin RNA in primary mouse cardiomyocytes, preventing MEF2C, Cx43, ANP and β‐MHC overexpression. These findings suggest that G9α histone methyltransferase‐mediated imbalance in histone H3K9me3 methylation plays a critical role in alcohol‐induced abnormal expression cardiomyogenesis‐related genes during pregnancy. Therefore, G9α histone methyltransferase may be an intervention target for congenital heart disease.

Interactions between the ERK1/2 signaling pathway and PCAF play a key role in PE‑induced cardiomyocyte hypertrophy

“…Co-IP was performed as described previously ( 26 ), using anti-phospho-(p-)ERK, anti-PCAF and anti-H3K9ac rabbit polyclonal antibodies with Dynabeads protein G magnetic beads (Invitrogen; Thermo Fisher Scientific, Inc.) for the immunoprecipitation and western blotting of primary cardiomyocytes. First, the primary antibody was bound to Protein G magnetic beads (according to the manufacturer's protocol).…”

“…Chromatin immunoprecipitation (ChIP). ChIP was performed as described previously (26). Formaldehyde (1%) was added to the homogenized cardiomyocytes to cross-link the DNA-protein complex, and incubate at 37˚C for 15 min.…”

Environmental Alterations during Embryonic Development: Studying the Impact of Stressors on Pluripotent Stem Cell-Derived Cardiomyocytes

“…On day 11 post-differentiation, ethanol significantly suppressed the expressions of important cardiac transcripts required for the differentiation (i.e., NKX2-5, MEF2C, TBX5, HAND2 and aMHC) and maturation (i.e., CX43 and TNNC1). Transcriptional alterations of specific cardiac genes and increased oxidative stress have been also observed in foetal mice, leading to heart dysplasia and CHD [216]. Indeed, alcohol exposure reduces histone methyltransferase (HMT) activity in the heart [216].…”

Construction and investigation of a circRNA-associated ceRNA regulatory network in Tetralogy of Fallot

“…Current knowledge and understanding have shown that temporal and spatial expression patterns of heart development-related genes are essential in the regulation of cardiomyogenesis, which means that both genetic and epigenetic factors play a crucial role throughout development [ 8 , 9 ]. Abnormal functional connectivity in the regulation network leads to failure of cardiac cell lineage specification, commitment, and differentiation [ 10 , 11 ].…”