FunctionSmall GTP-binding protein which cycles between an inactive GDP-bound and an active GTP-bound form, and the rate of cycling is regulated by guanine nucleotide exchange factors (GEF) and GTPase-activating proteins (GAP). GTP-binding protein that does not act as an allosteric activator of the cholera toxin catalytic subunit. Requires assistance from GTPase-activating proteins (GAPs) like RP2 and PDE6D, in order to cycle between inactive GDP-bound and active GTP-bound forms. Required for normal cytokinesis and cilia signaling.
Tissue specificityExpressed in the retina. Strongly expressed in connecting cilium, the myoid region of the inner segments (IS) and in cone photoreceptors (at protein level).
Sequence similaritiesBelongs to the small GTPase superfamily. Arf family.
Cellular localizationGolgi apparatus membrane. Cytoplasm > cytoskeleton > spindle. Nucleus. Cytoplasm > cytoskeleton > centrosome. Cytoplasm. Cell projection > cilium. Detected predominantly in the photoreceptor connecting cilium. Present on the mitotic spindle. Centrosome-associated throughout the cell cycle. Not detected to interphase microtubules.