Up-regulates the activity of the Rho guanine nucleotide exchange factor ARHGEF18 (By similarity). Involved in the regulation of the circumferential actomyosin belt in epithelial cells (PubMed:22006950). Promotes cellular adhesion, migration and motility in vitro and may play a role in wound healing (PubMed:23664528). May have a role in mediating cytoskeletal changes associated with steroid-induced cell differentiation (PubMed:14521927). Interacts (via FERM domain) with ARHGEF18 (via C-terminus); the interaction activates ARHGEF18. Accumulates along apical cell-cell boundaries and is also detected in the cytoplasm in a punctate manner. Expressed at higher levels in acute wounds than chronic wounds with increased expression in healing wounds, especially at the leading wound edge (PubMed:23664528). Isoform 1 is highly expressed in brain. Isoform 2 is highly expressed in testis with lower levels in prostate and breast (PubMed:14521927). By the androgen dihydrotestosterone (DHT). May be negatively regulated by phosphorylation.