Human cytomegalovirus (HCMV) is known to incorporate protein phosphatase 1 (PP1) into its tegument, suggesting a potential role in the viral life cycle. This research project aims to characterize the interactome of PP1 during HCMV infection. Our approach combines co-immunoprecipitation and mass spectrometry to identify human and viral proteins that interact with PP1 during HCMV infection, thereby aiming to gain new insights into the biological rationale behind PP1's incorporation by HCMV.