The murine gammaherpesvirus-68 M11 protein inhibits Fas- and TNF-induced apoptosis

The murine gammaherpesvirus-68 (MHV-68) M11 gene encodes a protein predicte d to have limited homology to the bcl-2 family of proteins, Unlike most of the other viral bcl-2 homologues, which have both BH1 and BH2 domains conse rved with respect to bcl-2, the M11 protein has a BH1 domain, but apparentl y lacks a BH2 domain. Transfection of HeLa cells with an epitope-tagged MHV -68 M11 construct showed that the protein is predominantly located in the c ytoplasm of cells. In HeLa cells, M11 inhibited apoptosis induced by anti-F as antibody and by TNF-alpha. Thus, despite its limited conservation with r espect to other bcl-2 family members, the MHV-68 M11 protein is a potent in hibitor of apoptosis.