Suppressor of RNA-mediated gene silencing, also known as post-transcriptional gene silencing (PTGS), a mechanism of plant viral defense that performs sequence-specific inhibition of viral mRNAs expression (PubMed:16186244, PubMed:31299487). The RNA silencing suppression activity is variable depending on the origin of the isolate (PubMed:31299487). Localizes to host ER-derived membranes. Belongs to the virgaviridae suppressor of RNA silencing family.