?cl41719: capping_2-OMTase_viral Superfamily
viral Cap-0 specific (nucleoside-2'-O-)-methyltransferase Cap-0 specific (nucleoside-2'-O-)-methyltransferase (2'OMTase) catalyzes the methylation of Cap-0 (m7GpppNp) at the 2'-hydroxyl of the ribose of the first nucleotide, using S-adenosyl-L-methionine (AdoMet) as the methyl donor. This reaction is the fourth and last step in mRNA capping, the creation of the stabilizing five-prime cap (5' cap) on mRNA. Some dsDNA and dsRNA viruses, like the bluetongue virus (BTV), a member of the Reoviridae family, and Vaccinia virus, a member of the Poxviridae family, as well as some ss(+)RNA viruses, like Flaviviridae and Nidovirales, cap their mRNAs and encode their own 2'OMTase. In BTV, all four reactions are catalyzed by a single protein, VP4. In Vaccinia, the activity is located in the processing factor of the poly(A) polymerase, VP39. |
Jiyao W et al.(2023). "The conserved domain database in 2023.",