A Genome-Wide Small Interfering RNA Screen Identifies Host Factors Required for Vesicular Stomatitis Virus Infection

Viruses are dependent on their host cells for replication and thus have evolved in intimate association with them. The identification of host factors required for viral infection has led to advances in both viral and cellular biology. Vesicular stomatitis virus (VSV), a negative-sense RNA virus, replicates in all eukaryotic cells in culture, suggesting that the host requirements for its replication are ubiquitous. In this study, we performed a genome-wide small interfering RNA screen of human cells in culture and identified multiple cellular genes that influence the entry and replication of VSV. From a list of >300 genes, we selected the most promising candidates to perform further analysis to assign their functions to either the entry or intracellular replication step of infection. We implicate 3 new factors in VSV entry and 20 new factors in viral gene expression. These proteins have diverse cellular roles, including S-adenosylmethionine synthesis, respiration, and host translation machinery, underscoring the intimate relationship between VSV and the host cell. Together, these results provide a curated list of genes required for VSV replication. IMPORTANCE Replication of vesicular stomatitis virus (VSV) has long served as a model for understanding host-virus interactions and neuropathogenesis. We performed a genome-wide analysis of host factors and revealed genes critical for viral replication, including some involved in vesicular trafficking, cell cycling, and protein modification. Our results provide an enriched list of host factors that are required for specific stages of VSV entry and gene expression. This study may also potentially expand the repertoire of targets for antiviral therapy against negative-strand RNA viruses.