Dinoflagellate mRNA is pervasively modified with m1A

N1-methyladenosine (m1A) is a very rare RNA modification in mammalian mRNA, which occurs in sequences resembling the T-loop of tRNAs and may not have significant effects on gene expression. A new study in this issue now reports that m1A is abundant and dynamic in the 3′UTR of mRNAs of dinoflagellates, and could have an important role in post-transcriptional gene expression regulation in these organisms. Unlike the scarce presence in typical eukaryotes, m1A is prevalent in dinoflagellate mRNA, m1A levels correlate with the expression of metabolism-related genes and respond to nitrogen starvation.