Plays a role in the maturation of immature virions to infectious particles. May also participate in viral transcription. Interacts with capping enzyme RAP94, the two large RNA polymerase subunits RPO147 and RPO132, the two early transcription factor subunits E6 and A7, one of the capping enzyme subunits D1, the nucleoside triphosphate phosphohydrolase D11, two core proteins A12 and A3, and a virion protein E2. Belongs to the chordopoxvirinae A19 family.