A 5'-uridine amplifies miRNA/miRNA* asymmetry in Drosophila by promoting RNA-induced silencing complex formation.

ABSTRACT:

Background

MicroRNA (miRNA) are diverse in sequence and have a single known sequence bias: they tend to start with uridine (U).

Results

Our analyses of fly, worm and mouse miRNA sequence data reveal that the 5'-U is recognized after miRNA production. Only one of the two strands can be assembled into Argonaute protein from a single miRNA/miRNA* molecule: in fly embryo lysate, a 5'-U promotes miRNA loading while decreasing the loading of the miRNA*.

Conclusion

We suggest that recognition of the 5'-U enhances Argonaute loading by a mechanism distinct from its contribution to weakening base pairing at the 5'-end of the prospective miRNA and, as recently proposed in Arabidopsis and in humans, that it improves miRNA precision by excluding incorrectly processed molecules bea

SUBMITTER: Seitz H 

PROVIDER: S-EPMC3127740 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature