Figure 5.

β-PIX can drive invadopodia formation. (a) MDA-MB-231 cells mock transfected, expressing GFP alone or expressing GFP-β-PIX were seeded on TRITC-gelatin-coated coverslips for 3 h, fixed and stained for F-actin cells were scored for the presence of actin spots with underlying gelatin degradation. (b) The gelatin degradation assay results from cells described in (a) were analysed using ImageJ software. (c) Representative images of GFP alone and GFP-β-PIX-expressing cells indicating the level of gelatin degradation and the partial co-localization of β-PIX with areas of degradation (arrow). (d) Representative image of a MDA-MB-231 cell expressing GFP-β-PIX and treated with DMOG for 6 h prior to seeding on a gelatin-coated coverslip. Arrowhead indicates co-localization of β-PIX, actin puncta and gelatin degradation. (e) MDA-MB-231 cells were mock transfected, or transfected with con or HIF-1α-specific siRNA oligos; some cells were then further transfected with GFP-β-PIX as indicated. All cells were then treated with DMOG for 6 h, then seeded on TRITC-gelatin-coated coverslips for 3 h, fixed and stained for F-actin. Cells were scored for the presence of actin spots with underlying gelatin degradation.