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EIF4GI facilitates the MicroRNA-mediated gene silencing.

ABSTRACT: MicroRNAs (miRNAs) are small noncoding RNAs that mediate post-transcriptional gene silencing by binding to complementary target mRNAs and recruiting the miRNA-containing ribonucleoprotein complexes to the mRNAs. However, the molecular basis of this silencing is unclear. Here, we show that human Ago2 associates with the cap-binding protein complex and this association is mediated by human eIF4GI, a scaffold protein required for the translation initiation. Using a cap photo-crosslinking method, we show that Ago2 closely associates with the cap structure. Taken together, these data suggest that eIF4GI participates in the miRNA-mediated post-transcriptional gene silencing by promoting the association of Ago2 with the cap-binding complex.

SUBMITTER: Ryu I

PROVIDER: S-EPMC3567085 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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eIF4GI facilitates the MicroRNA-mediated gene silencing.

Ryu Incheol I Park Ji Hoon JH An Sihyeon S Kwon Oh Sung OS Jang Sung Key SK

PloS one 20130207 2

MicroRNAs (miRNAs) are small noncoding RNAs that mediate post-transcriptional gene silencing by binding to complementary target mRNAs and recruiting the miRNA-containing ribonucleoprotein complexes to the mRNAs. However, the molecular basis of this silencing is unclear. Here, we show that human Ago2 associates with the cap-binding protein complex and this association is mediated by human eIF4GI, a scaffold protein required for the translation initiation. Using a cap photo-crosslinking method, we ...[more]

PMID: 23409027

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