May play a role in the regulation of RhoA GTPase by guanine nucleotide-binding alpha-12 (GNA12) and alpha-13 (GNA13). Acts as guanine nucleotide exchange factor (GEF) for RhoA GTPase and may act as GTPase-activating protein (GAP) for GNA12 and GNA13. Involved in neurotrophin-induced neurite outgrowth. Interacts with GNA12 and GNA13 through the RGS domain. Interacts with RHOA, PLXNB1 and PLXNB2. Interacts with SLC1A6 (By similarity). Interacts (via DH domain) with GCSAM (via C-terminus). Translocated to the membrane upon stimulation. Ubiquitously expressed. The poly-Pro region is essential for plasma membrane localization upon stimulation. Phosphorylated by MAP kinase p38 (MAPK11, MAPK12, MAPK13 and/or MAPK14). Ubiquitinated by the BCR(KLHL20) E3 ubiquitin ligase complex when previously phosphorylated by MAP kinase p38 (MAPK11, MAPK12, MAPK13 and/or MAPK14), leading to its degradation, thereby restricting RhoA activity and facilitating growth cone spreading and neurite outgrowth.