Mechanism of miRNA-mediated inhibition of protein production in animals

Determine the exact molecular mechanism by which microRNA-mediated repression inhibits protein production in animals, distinguishing whether the primary effect occurs at translation initiation, translation elongation, co-translational protein degradation, or premature termination of translation.

Background

miRNAs repress gene expression via miRISC, frequently recruiting the CCR4-NOT deadenylase complex and decapping machinery, which can lead to mRNA decay and/or translational inhibition.

The review notes that, although multiple stages of translation have been implicated, the definitive mechanism for protein-level repression in animals remains unresolved and requires direct discrimination among initiation, elongation, co-translational degradation, and premature termination.