Interaction between Brassica yellows virus silencing suppressor P0 and plant SKP1 facilitates stability of P0 in vivo against degradation by proteasome and autophagy pathways

摘要: P0 protein of some polerovirus members can target ARGONAUTE1 (AGO1) to suppress RNA silencing. Although harbors an F-box-like motif reported be essential for interaction with S phase kinase-associated 1 (SKP1) and silencing suppression, it is the autophagy pathway that was shown contribute AGO1 degradation. Therefore, role P0-SKP1 in suppression remains unclear. We conducted global mutagenesis comparative functional analysis encoded by Brassica yellows virus (BrYV) (P0Br ). found several residues within P0Br are required local systemic activities. Remarkably, mutant , which failed interact SKP1, destabilized in vivo. Both 26S proteasome system play a destabilization protein. Furthermore, Nicotiana benthamiana SKP1 ortholog leads . Genetic analyses indicated -SKP1 not directly activity but facilitates stability ensure efficient suppression. Consistent these findings, infection BrYV requires Our results reveal novel strategy used facilitating viral suppressors against degradation plant cells.