Alternative titles; symbolsRGS9-BINDING PROTEINRGS9 ANCHOR PROTEIN; R9APHGNC Approved Gene Symbol: RGS9BPCytogenetic location: 19q13.11 Genomic coordinates (...
Alternative titles; symbols
HGNC Approved Gene Symbol: RGS9BP
Cytogenetic location: 19q13.11 Genomic coordinates (GRCh38): 19:32,675,847-32,678,299 (from NCBI)
▼ Cloning and Expression
Hu and Wensel (2002) cloned bovine R9ap from a retina cDNA library and identified the homologous human sequence by database analysis. The deduced R9AP protein contains 235 amino acids and has a C-terminal transmembrane domain. Northern blot analysis of several bovine and mouse tissues detected R9ap expression only in retina. By fractionation and Western blot analysis of bovine rod outer segment (ROS) membranes, Hu and Wensel (2002) determined that R9ap associates with Rgs9 (604067) in the ROS. Immunohistochemical analysis of mouse retina showed R9ap staining in the ROS and minor staining in the outer plexiform layer.
▼ Gene Function
By coimmunoprecipitation analysis, Hu and Wensel (2002) determined that bovine R9ap associated with a heterotetrameric complex containing Rgs9, Gnb5 (604447), and Gnat (see 139330) in detergent-solubilized ROS membranes. R9ap interacted specifically with the N-terminal domain of Rgs9. Hu and Wensel (2002) concluded that the C-terminal transmembrane domain of R9ap functions as the membrane anchor for the other largely soluble interacting partners.
Hu et al. (2003) determined that the formation of a membrane-bound complex with bovine R9ap increased the GTPase-accelerating activity of Rgs9 by a factor of 4.
By genomic sequence analysis, Hu and Wensel (2002) mapped the R9AP gene to chromosome 19q13.11.
▼ Molecular Genetics
Nishiguchi et al. (2004) identified a Guatemalan patient with bradyopsia (608415) who was homozygous for a frameshift mutation, insertion of a C at cDNA nucleotide 194 within codon 65 (R65) of the R9AP protein (607814.0001).
▼ ALLELIC VARIANTS ( 1 Selected Example):
R9AP, 1-BP INS, 194C
In a Guatemalan patient from a consanguineous union with prolonged electroretinal response suppression (PERRS; 608415), Nishiguchi et al. (2004) identified homozygosity for a 1-bp insertion of a cytidine at cDNA nucleotide 194 within codon 65 (R65) of the R9AP gene, likely to be a null allele. The patient's 2 sibs were unaffected heterozygotes. This mutation was not found among 93 control individuals or among screens of 614 patients with other hereditary retinal diseases.