The ROBO1 receptor regulates Rho GTPase activity through a ligand-dependent association with members of a GAP protein family called SRGAPs (SLIT-ROBO GAPs), SRGAP1, SRGAP2 and SRGAP3 (Wong et al. 2001, Bacon et al. 2011). Extracellular interaction between SLIT and ROBO increases the intracellular interaction between the CC3 motif of ROBO1 and the SH3 motif of the SRGAPs (Wong et al. 2001).