Fig 3.

The context-dependent TβRI nuclear transport is controlled by Ran GTPase activity. (A) Cells were transfected as indicated with plasmids encoding the wild-type Ran, constitutively active Ran(F35A), dominant negative Ran(T24N), or the empty vector. At 48 h after transfection, cells were treated with TGF-β for 0.5 h or left untreated, fractionated, or subjected to RanBP1 pulldown assay and analyzed by Western blotting. (B) BT474 and MDA-MB-231 cells were transfected with Ran constructs and treated with TGF-β as described above, followed by RanBP1 pulldown assay and Western blotting. (C) MCF10A cells cotransfected with Ran(F35A) and siRNAs of nucleolin, importin β1, or control sequence, as well as control MCF10A cells, were treated with TGF-β for 0.5 h and subjected to fractionation and Western blotting. Abbreviations are the same as in Fig. 2.