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Biochemical and single-molecule analyses of the RNA silencing suppressing activity of CrPV-1A.

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.

SUBMITTER: Watanabe M

PROVIDER: S-EPMC5737572 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Biochemical and single-molecule analyses of the RNA silencing suppressing activity of CrPV-1A.

Watanabe Mariko M Iwakawa Hiro-Oki HO Tadakuma Hisashi H Tomari Yukihide Y

Nucleic acids research 20171001 18

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-1 ...[more]

PMID: 28977639

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