Quantification of Rho GTPase levels important in regulating actin dynamics and migration. Rho GTPase protein levels were analyzed on day 6 by Western blotting. (A) Sbds-null cells expressed slightly lower Rac1, and greatly reduced Rac2 levels versus WT cells. Levels of Cdc42 and RhoA were unchanged between WT and Sbds-null cells. Band intensities were normalized to β-actin used as loading control. (B) Quantification of band intensities by densitometry illustrating slightly reduced Rac1 and greatly reduced Rac2 levels (n = 4): *P < .01.