YIPF5 is an essential host factor for porcine epidemic diarrhea virus double-membrane vesicle formation.

Porcine epidemic diarrhea virus (PEDV) is a major coronavirus in swine, causing substantial economic losses in the industry. To deepen our understanding of the PEDV-host cell interactions, we performed whole-genome CRISPR/Cas9 screens on porcine IPEC-J2 and IPI-2I cell lines to identify key host factors essential for PEDV infection. Our study identified the Yip family 5 (YIPF5) protein as a critical host factor, where its knockout suppressed PEDV infection by specifically affecting the virus replication stage. YIPF5 interacts with viral non-structural protein (nsp) 3, 4, and 6, facilitating the formation of double-membrane vesicles (DMVs), essential for replication organelle biogenesis. The knockout of YIPF5 interferes with the interaction between nsp3 and nsp4, consequently impacting the formation of DMVs mediated by these proteins. These findings establish YIPF5 as a key host factor involved in DMV formation during PEDV infection, highlighting its potential as a therapeutic target. IMPORTANCE: Coronaviruses pose serious health threats to both humans and animals. Identifying host genes critical for porcine epidemic diarrhea virus (PEDV) infection can uncover new therapeutic targets and enhance our understanding of coronavirus pathogenesis. In this study, we conducted genome-scale CRISPR/Cas9 screens in two porcine cell lines (IPEC-J2 and IPI-2I) and identified YIPF5 as an essential host factor for PEDV replication. Our results demonstrate that YIPF5 plays a pivotal role in the formation of PEDV-induced double-membrane vesicles (DMVs), which are crucial for viral replication. These findings shed new light on the molecular mechanisms of PEDV and suggest YIPF5 as a therapeutic target.