Figure 9. Cortactin binding to the Arp2/3 complex is critical for regulation of Golgi morphology.

A. Schematic of cortactin with mutant sites indicated: W22A (Arp2/3 binding mutant); 3Y (Src phosphorylation mutant); Δ4RP (F-actin binding mutant); and W525K (SH3 binding mutant). NTA represents the N-terminal acidic domain, YYY represents Src phosphorylation sites, and circles represent cortactin repeat domains. For B-D: FL = wild-type cortactin, LZ = empty vector, Sc = scrambled oligo. Others as indicated in A. B. Western blot analysis of cortactin mutant expression (top panel) and actin as a loading control (bottom panel) in stable SCC61 cells. C. Representative widefield images of the Golgi (GM130, green), actin (rhodamine-phalloidin, red) and Hoechst (blue) in the cortactin mutants. D. Quantitation of Golgi area to cell area ratio from n=3; >20 cells per independent experiment. Scale bar = 25 µm. Data are presented as box and whiskers plots with the box indicating the 25^th and 75^th percentiles, solid line indicating the median, and the whiskers indicating the 95% confidence intervals. *p<0.05