Analysis of the Role of RhoGDI1 and Isoprenylation in the Degradation of RhoGTPases

RhoGDI1 is one of the three major regulators of the Rho switch along with RhoGEFs and RhoGAPs. RhoGDI1 extracts prenylated Rho proteins from lipid membranes, sequesters them in the cytosol, and prevents nucleotide exchange or hydrolysis. In addition, RhoGDI1 protects prenylated Rho proteins from degradation. Here, we describe techniques to monitor Rho proteins degradation upon depletion of RhoGDI1 and their dependence upon prenylation for degradation.