Disease relevance of Rods (Retina)

• Although the cell death and retinal degeneration associated with RP have been suggested to result from improper folding and accumulation of the mutant proteins in rod photoreceptor cells, this may not account for the disease in all cases [1].
• High-dose isotretinoin was given daily for 2 months and produced systemic toxicity, but this caused no histological loss of rod photoreceptors, and rod-driven electroretinogram amplitudes were normal after prolonged dark adaptation [2].
• A mutation in the gene for the rod photoreceptor molecule rhodopsin causes congenital night blindness [3].
• CONCLUSIONS: These results suggest that the function of mGluR8 of modulating the cytosolic Ca2+ concentration and thereby potentially the release of neurotransmitter from rod spherules, the axon terminal systems of rod photoreceptors, is mediated by a pertussis toxin-sensitive G protein potentially via the betagamma subunit [4].
• Rhodopsin, an integral membrane protein of rod photoreceptor cells, induces an experimental autoimmune uveitis (EAU) when injected into Lewis rats [5].

High impact information on Rods (Retina)

• During postnatal development, Rb is expressed in proliferating retinal progenitor cells and differentiating rod photoreceptors [6].
• The protein neural retina leucine zipper (Nrl) is a basic motif-leucine zipper transcription factor that is preferentially expressed in rod photoreceptors [7].
• Furthermore, the maximal photoresponse of Rom1-/- rod photoreceptors was lower than that of controls [8].
• Outer segment discs of rod photoreceptors in Rpe65-/- mice are disorganized compared with those of Rpe65+/+ and Rpe65+/- mice [9].
• Retinitis pigmentosa (RP) represents the most common mendelian degenerative retinopathy of man, involving death of rod photoreceptors, cone cell degeneration, retinal vessel attenuation and pigmentary deposits [10].

Chemical compound and disease context of Rods (Retina)

• Naturally occurring mutations of the beta subunit of the cyclic guanosine monophosphate (cGMP) phosphodiesterase (beta-PDE) gene in rod photoreceptors of mice and dogs are similar to one of the inherited retinal degenerations termed retinitis pigmentosa in humans [11].

Biological context of Rods (Retina)

• The hyperpolarizing receptor potential in vertebrate rod photoreceptors appears to be mediated by the second messenger, cyclic GMP [12].
• We mapped the first autosomal dominant RP (adRP) gene to chromosome 3q, close to the gene encoding rhodopsin, a rod photoreceptor pigment protein [13].
• Localization of peripherin/rds in the disk membranes of cone and rod photoreceptors: relationship to disk membrane morphogenesis and retinal degeneration [14].
• Structural and functional rescue of murine rod photoreceptors by human rhodopsin transgene [15].
• Chromatin immunoprecipitation assays on mouse retina demonstrated that Nr2e3 and Crx co-occupy the promoter/enhancer region of several rod and cone genes in the rod photoreceptor cells [16].

Anatomical context of Rods (Retina)

• Reporter expression indicated that connexin36 was present in multiple retinal neurons including rod photoreceptors, cone bipolar cells, and AII amacrine cells [17].
• In Rp1(-/-) mice, the number of rod photoreceptors decreased progressively over a period of 1 year, whereas that of cone photoreceptors did not change for at least 10 months [18].
• These results suggest that the rcd1 gene encodes the rod photoreceptor PDE beta subunit and that a nonsense mutation in this gene is responsible for the production of a nonfunctional rod PDE and the photoreceptor degeneration in the rcd1/rcd1 Irish setter dogs [19].
• We conclude that the absence or paucity of functional cGMP-gated cation channels in the plasma membrane is deleterious to rod photoreceptors and is an uncommon cause of RP [20].
• To study the mechanisms regulating axon or dendrite growth from local circuit neurons, neurite outgrowth from amacrine cells and rod photoreceptor cells derived from the rat was examined in vitro on immunopurified forms of NCAM, L1, and N-cadherin, three well-characterized adhesive molecules found in the developing retina [21].

Associations of Rods (Retina) with chemical compounds

• Furthermore, in retinal rod photoreceptors the low cytoplasmic concentration of cyclic GMP means that channels exist primarily in partially liganded states, so it is important to determine how such channels behave [22].
• Interaction of glutamic-acid-rich proteins with the cGMP signalling pathway in rod photoreceptors [23].
• Rhodopsin, the visual pigment of retinal rod photoreceptor cells, is a membrane glycoprotein which consists of a single polypeptide chain (opsin) to which a chromophoric prosthetic group (II-cis-retinaldehyde) and two asparagine-linked oligosaccharide chains are covalently attached [24].
• Taurine potentiates the production of rod photoreceptors, and this induction is inhibited by strychnine, an antagonist of glycine receptors, and bicuculline, an antagonist of GABA receptors [25].
• Taurine, a multifunctional amino acid prevalent in developing nervous tissues, regulates the number of rod photoreceptors in developing postnatal rodent retina [26].

Gene context of Rods (Retina)

• Hemizygotes from the RP24 family have early onset of rod photoreceptor dysfunction; cone receptor function is normal at first, but there is progressive loss [27].
• The Leber congenital amaurosis gene product AIPL1 is localized exclusively in rod photoreceptors of the adult human retina [28].
• Altogether, our findings suggest that Nr2e3 is a dual-function transcriptional regulator that acts in concert with Crx to promote and maintain the function of rod photoreceptors [16].
• Photoreceptor-specific nuclear receptor NR2E3 functions as a transcriptional activator in rod photoreceptors [29].
• The retinitis pigmentosa GTPase regulator (RPGR) interacts with novel transport-like proteins in the outer segments of rod photoreceptors [30].

Analytical, diagnostic and therapeutic context of Rods (Retina)

• Immunohistochemistry demonstrated that Crx and Nr2e3 are co-expressed by rod photoreceptors and their precursors [16].
• By PCR analysis and cloning of the respective cDNA, we show that the chick pineal expresses the alpha-subunit of the cyclic nucleotide-gated (CNG) channel of rod photoreceptors and two short forms of the cone CNG channel [31].
• We tested this hypothesis by site-directed mutagenesis in a rat olfactory channel (rOCNC1) and a bovine rod photoreceptor channel (Brcng) [32].
• PURPOSE: In animal models of retinitis pigmentosa, rod photoreceptor degeneration eventually leads to loss of cone photoreceptors [33].
• In situ hybridization analyses indicate that, in the eye, IPM 150 mRNA is expressed specifically by cone and rod photoreceptor cells [34].

References