Western blots were performed per our previous publication 12 (link). Briefly, tissue was homogenized in Complete Lysis-M buffer containing protease inhibitor together with phosphatase inhibitors (Roche Applied Science, Indianapolis, IN). Protein lysate was collected by centrifugation and protein concentrations were determined by Bio-Rad protein assay kit (Bio-Rad Laboratories, Hercules, CA). A total of 60mg protein lysate was loaded into each lane of a 10% SDS gel. Proteins were transferred to a nitrocellulose membrane, blocked with 5% non-fat milk and incubated with primary antibodies at 4°C overnight on a slow rocker. Primary antibodies used include mouse anti-Rac1 (1:500, BD Bioscience, San Jose, CA) or mouse anti-V5. Internal control antibodies such as mouse anti-GAPDH (1:500, Cell Signaling Technology, Danvers, MA) or rabbit anti-actin (1:500, Santa Cruz Biotechnology) were used. Membranes were incubated with secondary antibodies for one hour at room temperature [IRDye conjugated donkey anti-rabbit IgG or anti-mouse IgG (1:2000, Rockland Immunochemicals Inc., Gilbertsville, PA)]. Odyssey v.1.2 software (LI-COR Biosciences, Lincoln, NE) was used to convert color images to gray scale images.