Biochemical and single-molecule analyses of the RNA silencing suppressing activity of CrPV-1A. Issue 18 (24th August 2017)

• Record Type: Journal Article
• Authors: Watanabe, Mariko; Iwakawa, Hiro-oki; Tadakuma, Hisashi; Tomari, Yukihide
• Is Part Of: Nucleic acids research. Volume 45:Issue 18(2017)
• Page Start: 10837
• Page End: 10844
• Publication Date: 2017-08-24
• Subjects: Nucleic acids -- Periodicals; Molecular biology -- Periodicals; 572.805
• DOI: 10.1093/nar/gkx748
• Languages: English
• ISSNs: 0305-1048

Abstract

Abstract: Viruses often encode viral silencing suppressors (VSSs) to counteract the hosts' RNA silencing activity. The cricket paralysis virus 1A protein (CrPV-1A) is a unique VSS that binds to a specific Argonaute protein (Ago)—the core of the RNA-induced silencing complex (RISC)—in insects to suppress its target cleavage reaction. However, the precise molecular mechanism of CrPV-1A action remains unclear. Here we utilized biochemical and single-molecule imaging approaches to analyze the effect of CrPV-1A during target recognition and cleavage by Drosophila Ago2-RISC. Our results suggest that CrPV-1A obstructs the initial target searching by Ago2-RISC via base pairing in the seed region. The combination of biochemistry and single-molecule imaging may help to pave the way for mechanistic understanding of VSSs with diverse functions.