XB-ART-4375Science January 2, 2004; 303 (5654): 95-8.
Nuclear export of microRNA precursors.
MicroRNAs (miRNAs), which function as regulators of gene expression in eukaryotes, are processed from larger transcripts by sequential action of nuclear and cytoplasmic ribonuclease III-like endonucleases. We show that Exportin-5 (Exp5) mediates efficient nuclear export of short miRNA precursors (pre-miRNAs) and that its depletion by RNA interference results in reduced miRNA levels. Exp5 binds correctly processed pre-miRNAs directly and specifically, in a Ran guanosine triphosphate-dependent manner, but interacts only weakly with extended pre-miRNAs that yield incorrect miRNAs when processed by Dicer in vitro. Thus, Exp5 is key to miRNA biogenesis and may help coordinate nuclear and cytoplasmic processing steps.
PubMed ID: 14631048
Article link: Science
Grant support: GM-30220 NIGMS NIH HHS
Genes referenced: dicer1 ran xpo5 xpo5.2