Disease relevance of ARR3

• Retinoic acid upregulates cone arrestin expression in retinoblastoma cells through a Cis element in the distal promoter region [1].

High impact information on ARR3

• The localization of C-arrestin to cone photoreceptors suggests that it, like others in the arrestin family, may bind to phosphorylated receptors and participate in deactivation of the phototransduction cascade [2].
• A gene for human C-arrestin was mapped to the X chromosome, making C-arrestin a candidate for several inherited X-linked retinopathies [2].
• C-arrestin was isolated from a lambda MAX1 human retinal cDNA library and sequenced, revealing significant identity to known arrestins and divergence within the 3'-region [2].
• PURPOSE: To understand the genetic regulatory pathways underlying the retinoic acid (RA) induction of cone arrestin, gene array technology and other molecular tools were used to profile global gene expression changes in human retinoblastoma cells [3].
• RA stimulated hCAR promoter-luciferase activity in transient transfection studies [1].

Biological context of ARR3

• The human gene for X-arrestin at Xcen-Xq22 has been shown to be approximately 20kb in size and to consist of 17 exons and 16 introns [4].
• The common promoter elements between the cone-expressed genes, X-arrestin and color opsins, include the TATA box, PCE-1, and CRX-binding sequences, the combination of which might be important for directing cone-specific expression [4].
• Double labeling with peanut agglutinin (PNA) and wheat germ agglutinin (WGA) supported a cone-dominant phenotype for the surviving photoreceptors in the LCA retina, as did double labeling for cone arrestin, and rod and cone recoverin [5].
• GRK1-dependent phosphorylation of S and M opsins and their binding to cone arrestin during cone phototransduction in the mouse retina [6].
• RA's effect was blocked by either RNA or protein synthesis inhibitors; however, hCAR mRNA's stability was not affected by RA, as determined by RNA decay experiments [1].

Anatomical context of ARR3

• The cone arrestin signal was restricted to the residual photoreceptor inner segments and was not detected in the cell bodies, axons, or axon terminals of the surviving photoreceptors [5].
• In order to delineate the promoter structure necessary for the pan-cone-specific expression of X-arrestin, the expression of the gene in retinoblastoma cell lines was investigated, and a structure-function analysis of the promoter was conducted in the appropriate cellular substrate [7].

Associations of ARR3 with chemical compounds

• The promoter elements, common to both the X-arrestin and S-antigen genes, include the Ret-1/PCE-1 (PCE-1-like in X-arrestin), CRX, and the thyroid hormone/retinoic acid-responsive sequences, the former two being present in a number of photoreceptor-expressed genes [4].
• The glycine receptor antibody mAb4a labelled a minority of the cone photoreceptors identified by an antibody specific for cone arrestin [8].

Enzymatic interactions of ARR3

• Binding studies revealed no binding of cArr to rhodopsin regardless of whether it was bleached and/or phosphorylated. cArr also failed to bind to heparin-Sepharose under conditions which rod arrestin (rArr) bound to the column [9].

Other interactions of ARR3

• In single and double label experiments, the localization of X-arrestin immunoreactivity was compared with immunolabeling patterns obtained with antibodies to red/green cone opsin, rhodopsin, and S-antigen [10].
• The majority of cones in the T-17-M and P-23-H retinas were cytologically normal but showed loss of immunoreactivity for the cytoplasmic proteins 7G6, calbindin, and X-arrestin [11].

Analytical, diagnostic and therapeutic context of ARR3

• The mRNA for C-arrestin was visualized by in situ hybridization, localizing in the retina with cone photoreceptors and in the pineal to a subpopulation of pinealocytes [2].
• Affinity-purified anti-peptide antibody to human X-arrestin was prepared, and used in Western blot analysis of human retinal proteins and for immunohistochemistry on human retinal sections [10].
• We purified cArr from bovine retinas by sequential column chromatography using DEAE-cellulose, gel filtration and mono Q columns [9].
• Immunohistochemical staining displayed specific labeling of cArr in cone photoreceptors and immunoblotting identified a 46 kDa protein band [9].
• The population of cone photoreceptors expressing the glycine receptor was not correlated to a specific colour-sensitive subtype as demonstrated by single cell RT-PCR experiments using primers for S opsin, cone arrestin and glycine receptor beta subunit [8].

References