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Multilayer checkpoints for microRNA authenticity during RISC assembly.

ABSTRACT: MicroRNAs (miRNAs) function through the RNA-induced silencing complex (RISC), which contains an Argonaute (Ago) protein at the core. RISC assembly follows a two-step pathway: miRNA/miRNA* duplex loading into Ago, and separation of the two strands within Ago. Here we show that the 5' phosphate of the miRNA strand is essential for duplex loading into Ago, whereas the preferred 5' nucleotide of the miRNA strand and the base-pairing status in the seed region and the middle of the 3' region function as additive anchors to Ago. Consequently, the miRNA authenticity is inspected at multiple steps during RISC assembly.

SUBMITTER: Kawamata T

PROVIDER: S-EPMC3166454 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Multilayer checkpoints for microRNA authenticity during RISC assembly.

Kawamata Tomoko T Yoda Mayuko M Tomari Yukihide Y

EMBO reports 20110901 9

MicroRNAs (miRNAs) function through the RNA-induced silencing complex (RISC), which contains an Argonaute (Ago) protein at the core. RISC assembly follows a two-step pathway: miRNA/miRNA* duplex loading into Ago, and separation of the two strands within Ago. Here we show that the 5' phosphate of the miRNA strand is essential for duplex loading into Ago, whereas the preferred 5' nucleotide of the miRNA strand and the base-pairing status in the seed region and the middle of the 3' region function ...[more]

PMID: 21738221

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