CRM1 mediates nuclear-cytoplasmic shuttling of mature microRNAs

D Castanotto, R Lingeman… - Proceedings of the …, 2009 - National Acad Sciences
D Castanotto, R Lingeman, AD Riggs, JJ Rossi
Proceedings of the National Academy of Sciences, 2009National Acad Sciences
Drosha-processed microRNAs (miRNAs) have been shown to be exported from the nucleus
to the cytoplasm by Exportin 5, where they are processed a second time to generate mature
miRNAs. In this work we show that miRNAs also use CRM1 for nuclear-cytoplasmic
shuttling. Inhibition of CRM1 by Leptomycin B results in nuclear accumulation of miRNA
guide sequences. Nuclear to cytoplasmic transport can be actively competed by synthetic
small interfering RNAs, indicating that this pathway is shared by different classes of …
Drosha-processed microRNAs (miRNAs) have been shown to be exported from the nucleus to the cytoplasm by Exportin 5, where they are processed a second time to generate mature miRNAs. In this work we show that miRNAs also use CRM1 for nuclear-cytoplasmic shuttling. Inhibition of CRM1 by Leptomycin B results in nuclear accumulation of miRNA guide sequences. Nuclear to cytoplasmic transport can be actively competed by synthetic small interfering RNAs, indicating that this pathway is shared by different classes of processed small RNAs. We also find that CRM1 coimmunoprecipitates with Ago-1, Ago-2, Topo2α, EzH2, and Mta, consistent with a role of Argonautes and small RNAs in chromatin remodeling.
National Acad Sciences