Cholesterol 25-hydroxylase inhibits Senecavirus A replication by enzyme activity-dependent and independent mechanisms

Cholesterol 25-hydroxylase (CH25 H), as a host restriction factor, has been reported to take a broad-spectrum antiviral effect. However, the role of CH25H in Senecavirus A (SVA) infection remains unknown. In this study, we first demonstrate that overexpression of CH25H inhibits SVA replication. Consistently, knockdown or knockout of the endogens CH25H promotes SVA infection. Further, the anti-SVA effect of 25-hydroxycholesterol (25HC), which is the product of CH25H, operates via inhibition of viral attachment and replication. On the other hand, the CH25H mutant (CH25H-M) lacking hydroxylase activity still restricts SVA infection, which can selectively interact and degrade SVA 3A protein via the ubiquitin-proteasome manner. Altogether, these results suggest that CH25H has an antiviral function in SVA infection and provides an alternative manner to control SVA.