The methyltransferase dmain of the Respiratory Syncytial virus L protein catalyzes cap N7 and 2'-O-methylation

The genome replication and mRNA transcription of Respiratory syncytial virus (RSV) are both performed by viral RNA-dependent RNA polymerase L protein. The L protein catalyzes all required enzymatic activity for generating mRNA including mRNA capping and cap methylation. This paper biochemically demonstrated that RSV L catalyzes the N7- and 2'-O-methyation of the cap structure of a short RNA sequence that corresponds to the 5' end of viral mRNA via the methyltransferase with the C-terminal domain.