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E-cadherin Interacts With Posttranslationally-Modified AGO2 to Enhance miRISC Activity.

ABSTRACT: MicroRNAs (miRNAs) are small non-coding RNAs which post-transcriptionally suppress target mRNAs expression and/or translation to modulate pathophyological processes. Expression and function of miRNAs are fine-tuned by a conserved biogenesis machinery involves two RNase-dependent processing steps of miRNA maturation and the final step of miRNA-induced silencing complex (miRISC)-mediated target silencing. A functional miRISC requires Argonaute 2 (AGO2) as an essential catalytic component which plays central roles in miRISC function. We uncovered a post-translational regulatory mechanism of AGO2 by E-cadherin. Mechanistically, E-cadherin activates ERK to phosphorylate AGO2, along with enhanced protein glycosylation. Consequently, the phosphorylated AGO2 was stabilized and ultimately resulted in induced miRISC activity on gene silencing. This study revealed a novel pathway for miRNA regulation through an E-cadherin-mediated miRISC activation.

SUBMITTER: Li JN

PROVIDER: S-EPMC8287304 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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E-cadherin Interacts With Posttranslationally-Modified AGO2 to Enhance miRISC Activity.

Li Jie-Ning JN Sun Hui-Lung HL Wang Ming-Yang MY Chen Pai-Sheng PS

Frontiers in cell and developmental biology 20210705

MicroRNAs (miRNAs) are small non-coding RNAs which post-transcriptionally suppress target mRNAs expression and/or translation to modulate pathophyological processes. Expression and function of miRNAs are fine-tuned by a conserved biogenesis machinery involves two RNase-dependent processing steps of miRNA maturation and the final step of miRNA-induced silencing complex (miRISC)-mediated target silencing. A functional miRISC requires Argonaute 2 (AGO2) as an essential catalytic component which pla ...[more]

PMID: 34291046

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