Epitranscriptomics in the Heart: a Focus on mA.

Purpose Of Review: Post-transcriptional modifications are key regulators of gene expression that allow the cell to respond to environmental stimuli. The most abundant internal mRNA modification is N6-methyladenosine (mA), which has been shown to be involved in the regulation of RNA splicing, localization, translation, and decay. It has also been implicated in a wide range of diseases, and here, we review recent evidence of mA's involvement in cardiac pathologies and processes.

Recent Findings: Studies have primarily relied on gain and loss of function models for the enzymes responsible for adding and removing the mA modification. Results have revealed a multifaceted role for mA in the heart's response to myocardial infarction, pressure overload, and ischemia/reperfusion injuries. Genome-wide analyses of mRNAs that are differentially methylated during cardiac stress have highlighted the importance of mA in regulating the translation of specific categories of transcripts implicated in pathways such as calcium handling, cell growth, autophagy, and adrenergic signaling in cardiomyocytes. Regulation of gene expression by mA is critical for cardiomyocyte homeostasis and stress responses, suggesting a key role for this modification in cardiac pathophysiology.