pM45

Murine CMV (MCMV) is a natural herpesvirus infection of mice and thus provides a good model to study the effects of immune evasion on the host immune response. This paper investigates the effect of an immune evasion gene that profoundly inhibits presentation of a viral epitope on the immunodominance of that epitope. MCMV encodes three genes, m4, m6, and m152, which interfere with Ag presentation to CD8 T cells. The m4/gp34 protein binds to MHC class I molecules in the endoplasmic reticulum (ER) and on the cell surface. The m6/gp48 protein redirects class I to the lysosome for degradation. Finally, m152 retains class I in the ER cis-Golgi intermediate compartment.