The function of ARHGEF25 (Rho guanine nucleotide exchange factor 25, Ensembl gene identifier ENSG00000240771) is as follows. May play a role in actin cytoskeleton reorganization in different tissues since its activation induces formation of actin stress fibers. It works as a guanine nucleotide exchange factor for Rho family of small GTPases. Links specifically G alpha q/11-coupled receptors to RHOA activation. May be an important regulator of processes involved in axon and dendrite formation. In neurons seems to be an exchange factor primarily for RAC1. Involved in skeletal myogenesis (By similarity). {ECO:0000250, ECO:0000269|PubMed:11861769, ECO:0000269|PubMed:12547822, ECO:0000269|PubMed:15069594, ECO:0000269|PubMed:15632174, ECO:0000269|PubMed:16314529, ECO:0000269|PubMed:17606614}.