Vaccinia virus D10 decapping enzyme (D10)

The D10 decapping enzyme of vaccinia virus is a member of the Nudix hydrolase family, characterized by its conserved Nudix/MutT motif, which is required for its pyrophosphatase activity and substrate recognition. D10 is responsible for removing the 5’ methyl-G cap from both host and viral mRNAs, leading to rapid mRNA degradation during infection. This activity helps the virus suppress host gene expression and preferentially promote viral mRNA translation, particularly for viral transcripts containing a long poly(A) leader at the 5’ end. D10 is a promiscuous enzyme, targeting most cellular mRNAs (especially those from intron-containing genes) for degradation, while sparing intronless viral transcripts. This selectivity is believed to facilitate viral protein synthesis and modulate apoptosis, thereby optimizing viral replication. D10 has constitutive decapping activity, in contrast to tightly regulated cellular decapping enzymes, and its activity is essential for the vaccinia virus’ manipulation of host gene expression and translation.

Other names

D10 proteinVACV D10vaccinia decapping enzymeNudix hydrolase D10

inhibiting enzymatic decapping activity—preventing removal of the 5’ cap from mRNA, thus blocking mRNA degradation.