Fig. 3

KPNA2 regulates STMN1 by import of the transcription factors E2F1 and TFDP1. a HLE cells were treated with ctrl. or KPNA2 siRNAs and nuclear-cytoplasmic fractionation was performed after 72 h. Samples were immunoblotted using the indicated antibodies. b HLE cells were co-transfected with HA-tagged KPNA2 and Flag-tagged E2F1 or TFDP1. KPNA2 immunoprecipitation was performed and samples were immunoblotted using the indicated antibodies. c, d HLE cells were treated with ctrl. siRNA or siRNAs directed against E2F1 or TFDP1 and STMN1 expression was analyzed by immunoblotting (upper panel) or qRT-PCR (lower panel, n = 4; p < 0.05 (*)). e HLE cells were treated with siRNAs directed against E2F1 and TFDP1 and STMN1 expression was analyzed by immunoblotting (upper panel) or qRT-PCR (lower panel, n = 4; p < 0.05 (*)). f Illustration of the predicted E2F1 binding sites (BS) within the promoter region of STMN1. A non-coding region downstream of the promoter region served as negative control. g E2F1 was immunoprecipitated in HLE cells, ChIP assay was performed and precipitated DNA of the predicted STMN1 bindings sites, the positive control binding site (CDC2) and a control region (neg ctrl) was quantified using qRT-PCR. The bar diagram depicts one representative experiment. h TFDP1 was immunoprecipitated in HLE cells and ChIP assay was performed as described in (g). The bar diagram depicts one representative experiment