Characterization of the Human Cytomegalovirus Protein pUL71 and its Impact on viral Morphogenesis in Fibroblasts, Endothelial Cells and Macrophages

Abstract

We could show that HCMV morphogenesis is comparable in fibroblasts, endothelial cells and macrophages and that the absence or the functional impairment of the HCMV tegument protein pUL71 is affecting viral morphogenesis in all investigated cell types in a similar manner. pUL71 is associated with membranes within the AC at late stages of infection, and its absence causes impairment of secondary envelopment, morphological alterations of vesicles within the AC, and influences MVBs in infected fibroblasts, HUVEC, and MDM. Particularly a pUL71 palmitoylation site and a leucine zipper like motif are of great importance for pUL71 function and HCMV morphogenesis, while a C-terminal tetra-lysine motif only augments secondary envelopment. In contrast, a Vps4 interacting motif of pUL71seems to be not important for HCMV morphogenesis