E3 ubiquitin-protein ligase which promotes ubiquitination and subsequent degradation of host MHC-I, CD86, ICAM1 and CD1D molecules, presumably to prevent lysis of infected cells by cytotoxic T-lymphocytes and NK cell. Binds target molecules through transmembrane interaction. E3 ubiquitin-protein ligases accept ubiquitin from specific E2 ubiquitin-conjugating enzymes, and then transfer it to target protein. The result of this ubiquitination is the enhancement of the endocytosis of the target chain and the delivery to the lysosome, where it is proteolytically destroyed. Specific for HLA-A and HLA-B2 alleles. S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N(6)-ubiquitinyl-[acceptor protein]-L-lysine. Protein modification; protein ubiquitination. Binds human MHC-I, CD86, ICAM1 and CD1D. Probably exerts its effects at the plasma membrane during viral infection.