Emerging Roles of N6-Methyladenosine (m6A) Epitranscriptomics in Toxicology.

Epitranscriptomics, the study of chemically modified RNAs, is a burgeoning field being explored in a variety of scientific disciplines. Of the currently known epitranscriptomic modifications, N6-methyladenosine (m6A) methylation is the most abundant. The m6A modification is predominantly regulated by 3 tiers of protein modulators classified as writers, erasers, and readers. Depending upon cellular needs, these proteins function to deposit, remove, or read the methyl modifications on cognate mRNAs. Many environmental chemicals including heavy metals, pesticides, and other toxic pollutants, are all known to perturb transcription and translation machinery to exert their toxic responses. As such, we herein review how the m6A modification may be affected under different toxicological paradigms. Furthermore, we discuss how toxicants can affect the 3 tiers of regulation directly, and how these effects influence the m6A-modified mRNAs. Lastly, we highlight the disparities between published findings and theories, especially those concerning the m6A reader tier of regulation. In the far-reaching field of toxicology, m6A epitranscriptomics provides another enticing avenue to explore new mechanisms and therapies for a diverse range of environmentally linked disorders and diseases.