Skip to main content


Fig. 3 | BMC Molecular Biology

Fig. 3

From: Sumoylation in p27kip1 via RanBP2 promotes cancer cell growth in cholangiocarcinoma cell line QBC939

Fig. 3

Sumoylation p27kip1 is indispensable for its nucleus-cytoplasmic translocation mediated by Crm-1. Nuclear and cytoplasmic protein were separately extracted. a shows that p27kip1 expression in the nucleus is reduced after overexpression (OE) of Crm-1 in QBC939 cells. Also, as we transfect the HA-RanBP2 plasmid into QBC939 cells, p27kip1 expression in the nucleus was decreased (b). Moreover, when we transfect QBC939-HA-RanBP2 cells with siRNA suppressing Crm-1, p27kip1 level was rescued in the nucleus (b). Additionally, immunofluorescence staining with anti-flag antibody also verifies that Crm-1 overexpression can suppress nuclear p27kip1 (c) while the level of a K73R point mutated form of p27kip1 in the nucleus cannot be changed by Crm-1 overexpression (c), in which the fluorescence intensity was determined by the red signal/blue signal in each cell’s nuclear area. Further, we found the phosphorylated form of CDK-2 in the nucleus was reduced when Crm-1 overexpressed in QBC939 cells (d)

Back to article page