Plays a critical role in the regulation of enzymes involved in nucleotide cycle in photoreceptors (  ). Inhibits the basal catalytic activity and the GCAP-stimulated activity of GUCY2D and GUCY2F, two retinal guanylyl cyclases involved in the production of cGMP in photoreceptors ( , ). Involved in the transport of GUCY2D and GUCY2F to their target sites in the photoreceptor outer segment . Up-regulates the activity of GUK1, a kinase that also plays an essential role for recycling GMP and indirectly, cGMP . Plays an important role for the survival of rods and cones in the retina (By similarity).
Subcellular locations: Cell projection, Cilium, Photoreceptor outer segment, Photoreceptor inner segment, Endosome, Nucleus, Cytoplasm, Cytoplasm, Perinuclear region
Colocalizes with GUCY2E and GUCY2F in rods and cones photoreceptors. Colocalizes with GUK1 in photoreceptor inner segments and to a lesser extent in the outer plexiform layer (By similarity). Strong dot-like perinuclear staining in the epithelial cells .
Expressed in retina . Widely expressed (at protein level) . In the retina the strongest immunoreactivity is detected in the inner half of the cytoplasmic portion of the photoreceptor layer, where rods and cones are found, and the external half of the outer plexiform layer (at protein level) .