Identification of host cellular proteins interacting with porcine epidemic diarrhea virus M protein

Abstract:

[Background] The membrane protein (M) of porcine epidemic diarrhea virus (PEDV) plays an important role in the viral assembly process, membrane fusion and viral replication, but the mechanism of interaction between M protein and host cells is still unclear. [Objective] Co-immunoprecipitation technique coupled with LC-MS/MS were used to screen cellular proteins interacting with PEDV M protein, which can provide a foundation for revealing the function of M in viral multiplication. [Methods] PEDV DR13 vaccine strain was inoculated into monolayer of Vero cells at a MOI of 0.1. After 36 hours of infection, the cells were collected and lysed. Host cellular proteins that interact with the M protein of PEDV were immunoprecipitated using the M monoclonal antibody, then identified by LC-MS/MS, and analyzed by gene ontology (GO) annotation. Among them, two interested cellular proteins were further confirmed with Co-IP and cellular colocalization. [Results] Based on the analysis of the number of peptide segments, 218 cellular proteins interacting with M protein were identified. These host cellular proteins are closely related to protein synthesis, metabolism and cell signaling pathway transduction. Cell division cycle 42 (CDC42) and eukaryotic translation initiation factor 3 subunit L (eIF3L) were chosen for reverse Co-IP reconfirmation and colocalization analysis. The results showed that both CDC42 and eIF3L protein interact with M protein. [Conclusion] This study identified that PEDV M protein could interact with CDC42 and eIF3L proteins in host cells, and identified 60 other host proteins that might interact with M protein. The study is to provide an important theoretical basis for the study of the interaction between PEDV and host cell proteins.