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Autophagy modulates miRNA-mediated gene silencing and selectively degrades AIN-1/GW182 in C. elegans.

ABSTRACT: MicroRNAs (miRNAs) post-transcriptionally repress gene expression via the miRNA-induced silencing complex (miRISC), which includes miRNA, Argonaute and a GW182 family member. Here we show that in Caenorhabditis elegans, miRNA-mediated gene silencing is modulated by macroautophagy, a lysosome-mediated degradation process. Loss of autophagy activity suppresses developmental defects caused by partially impaired silencing of miRNA targets including the let-7 family and lsy-6. The C. elegans GW182 homolog AIN-1 is itself selectively degraded by autophagy and colocalizes with the p62 homolog SQST-1 in autophagy mutants. Thus, autophagy activity modulates miRNA-mediated gene silencing and degrades a core miRISC component.

SUBMITTER: Zhang P

PROVIDER: S-EPMC3674441 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Autophagy modulates miRNA-mediated gene silencing and selectively degrades AIN-1/GW182 in C. elegans.

Zhang Peipei P Zhang Hong H

EMBO reports 20130426 6

MicroRNAs (miRNAs) post-transcriptionally repress gene expression via the miRNA-induced silencing complex (miRISC), which includes miRNA, Argonaute and a GW182 family member. Here we show that in Caenorhabditis elegans, miRNA-mediated gene silencing is modulated by macroautophagy, a lysosome-mediated degradation process. Loss of autophagy activity suppresses developmental defects caused by partially impaired silencing of miRNA targets including the let-7 family and lsy-6. The C. elegans GW182 ho ...[more]

PMID: 23619095

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