Figure 6.

Effects of Src on phosphorylated FAK. (a) Western blots done on U87 cell lysates incubated with or without 10 μM PP2 for 30 minutes and probed for p-Y861-FAK and total FAK. P-Tyr861 decreased after PP2, consistent with Src activity being necessary for Tyr861 phosphorylation. (b) U87 cells transiently expressing Y530F-Src. Blots were probed for p-Y861 FAK and total FAK. Total amounts of proteins in panels (a) and (b) were monitored by stripping and blotting for β-actin. (c) Cells expressing transiently Y530F-Src (red) were fixed, immunostained for p-Y861-FAK (green), and cortactin (blue), used as a marker for invadopodia. Arrowheads show regions of colocalization of p-Tyr861-FAK, Src, and cortactin at invadopodia and cell membrane.