Mapping the Protein Phosphatase 1 Interactome in Human Cytomegalovirus Infection.

Area of Science:

• Cellular biology
• Virology
• Molecular mechanisms of viral infection

Background:

• Protein phosphorylation regulates cellular homeostasis.
• Human cytomegalovirus (HCMV) incorporates protein phosphatase 1 (PP1) into its virions.
• The biological significance of PP1 incorporation by HCMV is not well understood.

Purpose of the Study:

• To characterize the PP1 interactome during HCMV infection.
• To identify host and viral proteins interacting with PP1.
• To elucidate the role of PP1 interactions in viral replication and pathogenesis.

Main Methods:

• Co-immunoprecipitation assays.
• Mass spectrometry-based proteomics.
• Quantitative proteomics to analyze temporal changes.

Main Results:

• Identified 159 high-confidence interacting proteins (HCIPs) with PP1, including 126 human and 33 viral proteins.
• Observed significant temporal alterations in the PP1 interactome post-HCMV infection.
• Highlighted the involvement of PP1 interactors in intracellular trafficking, particularly the trafficking protein particle complex and Rab GTPases.

Conclusions:

• PP1 plays a critical role in HCMV-mediated manipulation of host intracellular trafficking for virion assembly and egress.
• The PP1 inhibitor 1E7-03 demonstrates potential as an antiviral agent by disrupting PP1-viral protein interactions.
• PP1 docking motifs are crucial for viral-host interactions, offering novel targets for antiviral strategies.