Figure 1.

RacB interactions. (A) Two-hybrid interactions between the CRIB domains of PAKa and PAKc and constitutively active and dominant-negative forms of Dictyostelium and human Rho family members. β-gal staining of colonies is shown. (B) The MBP-fused CRIBs of PAKa and PAKc were used in a pull-down assay with GST-RacB preloaded with or without GTP-γ-S (left panel). The right panel shows a similar experiment using the GST-CRIB domain of Dictyostelium WASP and myc-RacB. The bound proteins were analyzed by immunoblot assay with the anti-GST or anti-myc antibody.