FIGURE 7.
Tyrosine phosphorylation of RhoGDI at Tyr-156 is required for its dissociation from Cdc42 upon glucose stimulation. A, pEGFP-RhoGDI-WT and pEGFP-RhoGDI-Y156F plasmids were transiently expressed in MIN6 cells, after which cells were preincubated in MKRBB followed by glucose (Gluc) stimulation for 3 min. Detergent cell lysates were prepared for immunoprecipitation with anti-EGFP antibody. Immunoprecipitates were resolved on 12% SDS-PAGE for immunoblotting (IB) with the antibodies indicated. Data are representative of three independent experiments. B, ratio of Cdc42 binding to EGFP-RhoGDI proteins under basal conditions was set equal to 1 for normalization of glucose-stimulated ratio in each of three independent experiments; *, p < 0.05 versus basal.