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Biochemical identification of Argonaute 2 as the sole protein required for RNA-induced silencing complex activity.

ABSTRACT: RNA interference is carried out by the small double-stranded RNA-induced silencing complex (RISC). The RISC-bound small RNA guides the RISC complex to identify and cleave mRNAs with complementary sequences. The proteins that make up the RISC complex and cleave mRNA have not been unequivocally defined. Here, we report the biochemical purification of RISC activity to homogeneity from Drosophila Schnieder 2 cell extracts. Argonaute 2 (Ago-2) is the sole protein component present in the purified, functional RISC. By using a bioinformatics method that combines sequence-profile analysis with predicted protein secondary structure, we found homology between the PIWI domain of Ago-2 and endonuclease V and identified potential active-site amino acid residues within the PIWI domain of Ago-2.

SUBMITTER: Rand TA

PROVIDER: S-EPMC521941 | biostudies-literature | 2004 Oct

REPOSITORIES: biostudies-literature

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Biochemical identification of Argonaute 2 as the sole protein required for RNA-induced silencing complex activity.

Rand Tim A TA Ginalski Krzysztof K Grishin Nick V NV Wang Xiaodong X

Proceedings of the National Academy of Sciences of the United States of America 20040927 40

RNA interference is carried out by the small double-stranded RNA-induced silencing complex (RISC). The RISC-bound small RNA guides the RISC complex to identify and cleave mRNAs with complementary sequences. The proteins that make up the RISC complex and cleave mRNA have not been unequivocally defined. Here, we report the biochemical purification of RISC activity to homogeneity from Drosophila Schnieder 2 cell extracts. Argonaute 2 (Ago-2) is the sole protein component present in the purified, fu ...[more]

PMID: 15452342

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