GSE99169
UPF1/SMG7-dependent MicroRNA-mediated Gene Regulation
A majority of metazoan mRNAs are under microRNA (miRNA)/Argonaute (Ago)-mediated control of RNA stability at the post-transcriptional level. Although the molecular mechanism of the miRNA-mediated repression of target mRNAs through Ago/TNRC6 pathway have been largely elucidated, however, the existence of alternative TNRC6-independent miRNA-mediated post-transcriptional gene regulation pathway remains unknown. Here, we suggest that endogenous miRNAs (endo-miRNAs) can downregulate the target mRNAs via the alternative molecular pathway, Ago-associated UPF1/SMG7, core mediators of nonsense-mediated mRNA decay. Global analyses of mRNAs in a response to UPF1 RNA interference in miRNA-deficient cells reveal that 3'UTR-length-dependent mRNA decay by UPF1 requires endo-miRNA targeting via CUG motif. The repression of miRNA targets is more additively or synergistically accomplished by combination of Ago2 and UPF1 through UPF1-associated SMG7, recruiting CCR4-NOT deadenylase complex, in TNRC6-independent manner. We expect that the new miRNA-mediated mRNA decay pathway enables the miRNA targeting to become more predictable and expand the miRNA-mRNA regulatory network. Overall design: Examination of 11 different knockdown condition in HeLa cell type