GTPase-activating protein for RAC1 and perhaps CDC42, but not for RhoA small GTPase. May attenuate RAC1 signaling in neurons (By similarity). Homodimer (Probable). Forms a heterooligomer with SRGAP1 and SRGAP2 through its F-BAR domain. Interacts with WASF1. Probably interacts with ROBO1. Interacts with FASLG (By similarity). The F-BAR domain mediates oligomerization, binds membranes, and induces plasma membrane protrusions. Truncated N-terminus. Intron retention. Extended N-terminus. Probable cloning artifact. Aberrant splice sites.