Hu, H., Li, M., Labrador, J.P., McEwen, J., Lai, E.C., Goodman, C.S., Bashaw, G.J. (2005). Cross GTPase-activating protein (CrossGAP)/Vilse links the Roundabout receptor to Rac to regulate midline repulsion.  Proc. Natl. Acad. Sci. U.S.A. 102(12): 4613--4618.

FBrf0191476

Research paper

The regulators of the Rho-family GTPases, GTPase-activating proteins (GAPs) and guanine exchange factors (GEFs), play important roles in axon guidance. By means of a functional genomic study of the Rho-family GEFs and GAPs in Drosophila, we have identified a Rho-family GAP, CrossGAP (CrGAP), which is involved in Roundabout (Robo) receptor-mediated repulsive axon guidance. CrGAP physically associates with the Robo receptor. Too much or too little CrGAP activity leads to defects in Robo-mediated repulsion at the midline choice point. The CrGAP gain-of-function phenotype mimics the loss-of-function phenotypes of both Robo and Rac. Dosage-sensitive genetic interactions among CrGAP, Robo, and Rac support a model in which CrGAP transduces signals downstream of Robo receptor to regulate Rac-dependent cytoskeletal changes.

PMC555501 (PMC) (EuropePMC)