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AUF1 promotes let-7b loading on Argonaute 2.

ABSTRACT: Eukaryotic gene expression is tightly regulated post-transcriptionally by RNA-binding proteins (RBPs) and microRNAs. The RBP AU-rich-binding factor 1 (AUF1) isoform p37 was found to have high affinity for the microRNA let-7b in vitro (Kd = ∼ 6 nM) in cells. Ribonucleoprotein immunoprecipitation, in vitro association, and single-molecule-binding analyses revealed that AUF1 promoted let-7b loading onto Argonaute 2 (AGO2), the catalytic component of the RNA-induced silencing complex (RISC). In turn, AGO2-let-7 triggered target mRNA decay. Our findings uncover a novel mechanism by which AUF1 binding and transfer of microRNA let-7 to AGO2 facilitates let-7-elicited gene silencing.

SUBMITTER: Yoon JH

PROVIDER: S-EPMC4536308 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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AUF1 promotes let-7b loading on Argonaute 2.

Yoon Je-Hyun JH Jo Myung Hyun MH White Elizabeth J F EJ De Supriyo S Hafner Markus M Zucconi Beth E BE Abdelmohsen Kotb K Martindale Jennifer L JL Yang Xiaoling X Wood William H WH Shin Yu Mi YM Song Ji-Joon JJ Tuschl Thomas T Becker Kevin G KG Wilson Gerald M GM Hohng Sungchul S Gorospe Myriam M

Genes & development 20150801 15

Eukaryotic gene expression is tightly regulated post-transcriptionally by RNA-binding proteins (RBPs) and microRNAs. The RBP AU-rich-binding factor 1 (AUF1) isoform p37 was found to have high affinity for the microRNA let-7b in vitro (Kd = ∼ 6 nM) in cells. Ribonucleoprotein immunoprecipitation, in vitro association, and single-molecule-binding analyses revealed that AUF1 promoted let-7b loading onto Argonaute 2 (AGO2), the catalytic component of the RNA-induced silencing complex (RISC). In turn ...[more]

PMID: 26253535

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