Exportin-5 is responsible for the exclusion of siRNAs from the nucleus

Copyright information:Taken from " fluorescence analysis demonstrates active siRNA exclusion from the nucleus by Exportin 5"Nucleic Acids Research 2006;34(5):1369-1380.Published online 6 Mar 2006PMCID:PMC1390680.© The Author 2006. Published by Oxford University Press. All rights reserved () After 48 h total protein extracts from CRM1, siExp5-1 and siExp5-2 (100 nM) transfected cells were immunoblotted with antibodies against Exp5 and CRM1. α-Tubulin was used as a loading control. () HeLa SS6 cells were transfected with siCRM1 (left panel), siExp5-1 (right panel) or siExp5-2 (data not shown) and were microinjected 48 h later with a mixture consisting of 20 µM 3′2ntOh () labelled with Cy5 and 20 µM 5′5ntOh () short dsRNA labelled with Alexa488. The cells were analysed 10–15 min after microinjection by laser scanning microscopy. Scale bars = 20 µm. () Quantification of the translocation process. The confocal images were analysed by using fluorescence area intensity measurements in the nucleus and in the cytoplasm for the two RNA duplexes. The graph shows the ratio of fluorescence intensity nucleus/cytoplasm.