Interplay of RNA 2′-O-methylations with viral replication

Viral RNAs (vRNAs) are decorated by post-transcriptional modifications, including methylation of nucleotides. Methylations regulate biological functions linked to the sequence, structure, and protein interactome of RNA. Several RNA viruses were found to harbor 2′-O-methylations, affecting the ribose moiety of RNA. This mark was initially shown to target the first and second nucleotides of the 5′-end cap structure of mRNA. More recently, nucleotides within vRNA were also reported to carry 2′-O-methylations. The consequences of such methylations are still puzzling since they were associated with both proviral and antiviral effects. Here, we focus on the mechanisms governing vRNA 2′-O-methylation and we explore the possible roles of this epitranscriptomic modification for viral replication.