Regulator of G protein-coupled receptor (GPCR) signaling in phototransduction. Participates in the recovery phase of visual transduction via its interaction with RGS9-1 isoform. Acts as a membrane-anchor that mediates the targeting of RGS9-1 to the photoreceptor outer segment, where phototransduction takes place. Enhances the ability of RGS9-1 to stimulate G protein GTPase activity, allowing the visual signal to be terminated on the physiologically time scale. It also controls the proteolytic stability of RGS9-1, probably by protecting it from degradation. Specifically interacts with isoform RGS9-1 of RGS9. Interaction is decreased when RGS9-1 is phosphorylated at 'Ser-475'. Component of the RGS9-1-Gbeta5 complex composed of RGS9-1, Gbeta5 (GNB5) and RGS9BP. Predominantly expressed in photoreceptors of the retina. Weakly expressed in other areas of the central nervous system. Mice show light responses that recover at a abnormally slow rate. Belongs to the RGS7BP/RGS9BP family.