Figure 4
Polycystin-1 modulates focal adhesions distribution during migration. (A) Immunofluorescence images of MDCKZeo (clone F2) and MDCKPKD1Zeo (clone 36) cells plated for 5 h on fibronectin. Cells were stained for actin (Phalloidin-TRITC, red), paxillin (green) and nucleus (DAPI, blue). MDCKZeo cells have a round shape and peripheral clusters of paxillin; MDCKPKD1Zeo cells acquire a polarized and migratory phenotype, with focal adhesions of different dimensions. Bar: 25 μm. (B) Confocal images of immunofluorescence on MDCKZeo (clone F6) and MDCKPKD1Zeo (clone 36), plated overnight on fibronectin. Cells were stained for actin (Phalloidin-TRITC, red), paxillin (green) and nucleus (DAPI, blue). Images represent one confocal Z-section of the cell, on the right and below each image are projections along x and y axis, reconstructed with Volocity software. In all cell lines, paxillin staining is found on the ventral side and localizes in clusters (focal adhesions). MDCKPKD1Zeo cells maintain a polarized morphology and present numerous focal adhesions, while MDCKZeo cells have a round shape and a limited number of paxillin clusters, mainly localized at the periphery of the cell. Bar: 15 μm. (C-D) Representative confocal images of MDCKZeo (clone F2) and MDCKPKD1Zeo (clone 36) cells (C), and of mIMCDshCtrl (clone M4) and mIMCDshPkd1 (clone C16) cells (D), allowed to migrate in a 3 hours wound-healing assay on fibronectin and subsequently stained for actin (Phalloidin-TRITC), paxillin (green) and nucleus (DAPI, blue). Merged images, single channels and zoom-in of the boxed areas of paxillin are shown. Bar: 25 μm.