{Reference Type}: Journal Article {Title}: m6A regulates heterochromatin in mammalian embryonic stem cells. {Author}: Xu W;Shen H; {Journal}: Curr Opin Genet Dev {Volume}: 86 {Issue}: 0 {Year}: 2024 Jun 25 {Factor}: 4.665 {DOI}: 10.1016/j.gde.2024.102196 {Abstract}: As the most well-studied modification in mRNA, m6A has been shown to regulate multiple biological processes, including RNA degradation, processing, and translation. Recent studies showed that m6A modification is enriched in chromatin-associated RNAs and nascent RNAs, suggesting m6A might play regulatory roles in chromatin contexts. Indeed, in the past several years, a number of studies have clarified how m6A and its modulators regulate different types of chromatin states. Specifically, in the past 2-3 years, several studies discovered the roles of m6A and/or its modulators in regulating constitutive and facultative heterochromatin, shedding interesting lights on RNA-dependent heterochromatin formation in mammalian cells. This review will summarize and discuss the mechanisms underlying m6A's regulation in different types of heterochromatin, with a specific emphasis on the regulation in mammalian embryonic stem cells, which exhibit distinct features of multiple heterochromatin marks.