Published on Jan. 8, 2017 in J Am Chem Soc volume 139.
PubMed ID: 28107630
5-Hydroxymethylcytidine (hm(5)C) was recently identified as a direct metabolite of m(5)C in RNA. We investigated the stability of hm(5)C in human cells using bio-isotopologues and LC-MS/HRMS. This has led to the discovery of a second oxidative metabolite of m(5)C in RNA, namely 2'-O-methyl-5-hydroxymethylcytidine (hm(5)Cm). Subsequent quantitative analysis of total RNA from higher organisms revealed varying levels and TET-independent formation of this new RNA modification.