Guanine nucleotide exchange factor for ARF6 (PubMed:23603394). Induces cytoskeletal remodeling (By similarity). Interacts with ACTN1. Interacts (ARF6-bound form) with KCNK1; does not interact with KCNK1 in the absence of ARF6 (By similarity). Distributed uniformly on the plasma membrane, as well as throughout the cytoplasm during metaphase. Subsequently concentrated at patches in the equatorial region at the onset of cytokinesis, and becomes distributed in the equatorial region concurrent with cleavage furrow ingression. In later cytokinesis phases, fades away from the cleavage furrow and becomes uniformly distributed throughout the plasma membrane. Additional isoforms may exist. Isoform 2 is expressed in the brain. Belongs to the PSD family. Extended N-terminus.