R9AP, a membrane anchor for the photoreceptor GTPase accelerating protein, RGS9-1.
The regulator of G protein signaling (RGS)-9-1.G(beta 5) complex forms the GTPase accelerating protein for G(alpha t) in vertebrate photoreceptors. Although the complex is soluble when expressed in vitro, extraction of the endogenous protein from membranes requires detergents. The detergent extracts contain a complex of RGS9-1, G(beta 5), G(alpha t), and a 25-kDa phosphoprotein, R9AP (RGS9-1-Anchor Protein). R9AP is encoded by one intronless gene in both human and mouse. Full or partial cDNA or genomic clones were obtained from mice, cattle, human, zebrafish, and Xenopus laevis. R9AP mRNA was detected only in the retina, and the protein only in photoreceptors. R9AP binds to the N-terminal domain of RGS9-1, and anchors it to the disk membrane via a C-terminal transmembrane helix.
Hu
Guang
G
Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
Wensel
Theodore G
TG
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002462:Cell Membrane / Q000502:physiology; D003001:Cloning, Molecular; D018076:DNA, Complementary; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry; D020419:Photoreceptor Cells, Vertebrate / Q000502:physiology*; D017433:Protein Structure, Secondary; D020710:RGS Proteins / Q000378:metabolism*; D011817:Rabbits; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D012374:Rod Cell Outer Segment / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; D018076:DNA, Complementary; D008565:Membrane Proteins; D010446:Peptide Fragments; D020710:RGS Proteins; C464657:RGS9BP protein, human; D011994:Recombinant Proteins; C116925:regulator of g-protein signaling 9; D020558:GTP Phosphohydrolases