Revised Picture For mRNA Translation

Researchers have used sequencing methods to show that a methyl-modified base called N¹-methyladenosine (m¹A) is present near the start region of about one in every five mRNAs in human and mouse cells. The mRNAs so modified are translated into proteins at higher levels than unmodified ones. The work by Gideon Rechavi of Tel Aviv University, Chuan He of the University of Chicago, and coworkers suggests that m¹A helps regulate mRNA translation, possibly by marking the start codon for ribosome recognition (Nature 2016, DOI: 10.1038/nature16998). Several other similar RNA modifications are known, such as m⁶A, which accumulates near stop codons and affects RNA stability, translation, localization, and splicing. The m1A work thus “adds another layer of complexity and potential regulation to the fate of mRNA and hence gene regulation,” comments RNA modifications specialist Chengqi Yi of Peking University, a former member of the He group. The findings could spark follow-up studies to answer questions such as how the modification is made and erased, how it’s recognized and works mechanistically, what processes it regulates or is regulated by, and whether it’s a drug target.