E3 ubiquitin-protein ligase that mediates ubiquitination of host surface class I (MHC-I) H-2D(b)/H2-D1 and H-2K(b)/H2-K1 molecules before they exit the endoplasmic reticulum, leading to their degradation by the endoplasmic reticulum-associated degradation (ERAD) system, thus blocking the immune detection of virus-infected cells. Mediates ubiquitination of lysine, as well as serine and threonine residues present in the cytoplasmic tail of surface class I molecules. Promotes ubiquitination of hydroxylated serine or threonine residues via ester bonds instead of the classical isopeptide linkage. [E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine + [acceptor protein]-L-cysteine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-S-ubiquitinyl-L-cysteine. Protein modification; protein ubiquitination. Interacts with host UBE2J2. The DIRT (domain in between the RING-CH-type and the first transmembrane) region is essential to determine substrate residues that can be ubiquitinated. The RING-CH-type zinc finger (also named RINGV-type zinc-finger) mediates the E3 ubiquitin ligase activity. Murine herpesvirus 76 (MHV76) is identical to murine herpesvirus 68 except for a large deletion at the genome left end of the unique region.