Epitranscriptomics in the Heart: a Focus on m 6 A

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 (m 6 A), 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 m 6 A’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 m 6 A modification. Results have revealed a multifaceted role for m 6 A 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 m 6 A in regulating the translation of specific categories of transcripts implicated in pathways such as calcium handling, cell growth, autophagy, and adrenergic signaling in cardiomyocytes. Summary Regulation of gene expression by m 6 A is critical for cardiomyocyte homeostasis and stress responses, suggesting a key role for this modification in cardiac pathophysiology.