KPNA1, KPNA5, and KPNA6 are required for E2-dependent PHB2 nuclear import in breast cancer cells.

<p>(A) Immunoblotting analysis was performed to evaluate the subcellular localization of endogenous PHB2 in the BIG3- and KPNAs (KPNA1, KPNA5, and KPNA6)-depleted MCF-7 cells. MCF-7 cells were treated with siBIG3 and each siKPNA, followed by E2 ± ERAP for 24 h. Then, the cells were separated into cytoplasmic and nuclear fractions; (B) The nuclear translocation of PHB2 in KPNA-depleted MCF-7 cells in the presence of E2 and ERAP was evaluated. MCF-7 cells were treated with each siKPNA followed by E2 ± ERAP for 24 h. Then, the cells were separated into cytoplasmic (Cyto) and nuclear (N) fractions. The data are expressed the fold increase over cytoplasm fraction of untreated siEGFP, siKPNA1, siKPNA2, siKPNA5 or siKPNA6-transfected cells (set at 1.0), respectively. (C) The relationship among each KPNA was evaluated in KPNA-depleted MCF-7 cells in presence of E2 and ERAP. α/β-Tubulin (tubulin) and lamin B1 (lamin) were used as loading controls for the cytoplasmic (Cyto) and nuclear (N) fractions, respectively (A, B). Full-length images of immunoblots are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0127707#pone.0127707.s003" target="_blank">S3A–S3C Fig</a>.