External Ids for OPN4 Gene
Previous GeneCards Identifiers for OPN4 Gene
Opsins are members of the guanine nucleotide-binding protein (G protein)-coupled receptor superfamily. This gene encodes a photoreceptive opsin protein that is expressed within the ganglion and amacrine cell layers of the retina. In mouse, retinal ganglion cell axons expressing this gene projected to the suprachiasmatic nucleus and other brain nuclei involved in circadian photoentrainment. In mouse, this protein is coupled to a transient receptor potential (TRP) ion channel through a G protein signaling pathway and produces a physiologic light response via membrane depolarization and increased intracellular calcium. The protein functions as a sensory photopigment and may also have photoisomerase activity. Experiments with knockout mice indicate that this gene attenuates, but does not abolish, photoentrainment. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]
GeneCards Summary for OPN4 Gene
OPN4 (Opsin 4) is a Protein Coding gene. Diseases associated with OPN4 include Severe Nonproliferative Diabetic Retinopathy and Retinitis Pigmentosa 29. Among its related pathways are Peptide ligand-binding receptors and Circadian rythm related genes. Gene Ontology (GO) annotations related to this gene include G-protein coupled receptor activity and G-protein coupled photoreceptor activity. An important paralog of this gene is OPN3.
UniProtKB/Swiss-Prot for OPN4 Gene
Photoreceptor required for regulation of circadian rhythm. Contributes to pupillar reflex and other non-image forming responses to light. May be able to isomerize covalently bound all-trans retinal back to 11-cis retinal (By similarity).