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C3PO, an endoribonuclease that promotes RNAi by facilitating RISC activation.

ABSTRACT: The catalytic engine of RNA interference (RNAi) is the RNA-induced silencing complex (RISC), wherein the endoribonuclease Argonaute and single-stranded small interfering RNA (siRNA) direct target mRNA cleavage. We reconstituted long double-stranded RNA- and duplex siRNA-initiated RISC activities with the use of recombinant Drosophila Dicer-2, R2D2, and Ago2 proteins. We used this core reconstitution system to purify an RNAi regulator that we term C3PO (component 3 promoter of RISC), a complex of Translin and Trax. C3PO is a Mg2+-dependent endoribonuclease that promotes RISC activation by removing siRNA passenger strand cleavage products. These studies establish an in vitro RNAi reconstitution system and identify C3PO as a key activator of the core RNAi machinery.

SUBMITTER: Liu Y

PROVIDER: S-EPMC2855623 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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C3PO, an endoribonuclease that promotes RNAi by facilitating RISC activation.

Liu Ying Y Ye Xuecheng X Jiang Feng F Liang Chunyang C Chen Dongmei D Peng Junmin J Kinch Lisa N LN Grishin Nick V NV Liu Qinghua Q

Science (New York, N.Y.) 20090801 5941

The catalytic engine of RNA interference (RNAi) is the RNA-induced silencing complex (RISC), wherein the endoribonuclease Argonaute and single-stranded small interfering RNA (siRNA) direct target mRNA cleavage. We reconstituted long double-stranded RNA- and duplex siRNA-initiated RISC activities with the use of recombinant Drosophila Dicer-2, R2D2, and Ago2 proteins. We used this core reconstitution system to purify an RNAi regulator that we term C3PO (component 3 promoter of RISC), a complex of ...[more]

PMID: 19661431

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