Interaction between the human cytomegalovirus‑encoded UL142 and cellular Snapin proteins.

Human cytomegalovirus (HCMV) infection can cause severe illness in immunocompromised and immunodeficient individuals. As a novel HCMV-encoded major histocompatibility complex class I-related molecule, the UL142-encoded protein (pUL142) is capable of suppressing natural killer (NK) cell recognition in the course of infection. However, no host factors that directly interact with HCMV pUL142 have been reported so far. In order to understand the interactions between HCMV pUL142 and host proteins, the current study used yeast two-hybrid screening, a GST pull-down assay and an immunofluorescence assay. A host protein, the SNARE-associated protein Snapin, was identified to directly interact and colocalize with HCMV pUL142 in transfected human embryonic kidney-293 cells. Snapin is abundantly expressed in the majority of cells and mediates the release of neurotransmitters through vesicular transport in the nervous system and vesicle fusion in non-neuronal cells. It is hypothesized that HCMV pUL142 may have an impact on the neurotransmitter release process and viral dissemination via interaction with Snapin.