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Related to opsin: rhodopsin, opsonin, KIPRIS


Any of various light-sensitive proteins, especially one that is a constituent of a rhodopsin or other visual pigment found in the retina of the vertebrate eye.

[Probably back-formation from rhodopsin.]


(Biochemistry) the protein that together with retinene makes up the purple visual pigment rhodopsin
[C20: back formation from rhodopsin]


(ˈɒp sɪn)

any of several compounds that form the protein component of the light-sensitive pigment rhodopsin.
[1950–55; probably back formation from rhodopsin]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.opsin - retinal protein formed by the action of light on rhodopsin
protein - any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes; "a diet high in protein"
iodopsin - a violet photopigment in the retinal cones of the eyes of most vertebrates; plays a role in daylight vision
retinal purple, rhodopsin, visual purple - a red photopigment in the retinal rods of vertebrates; dissociates into retinene by light
References in periodicals archive ?
Guppies present a unique opportunity to systematically study multiple aspects of opsin evolution, asking whether it mirrors the pattern of parallel evolution of sexually selected traits.
The researchers speculate that the eyes' main light-sensing protein, one of many forms of opsin, may also be active in skin as a sensor for light.
Visual factors might be more important than the sex pheromone in the recognition of sex partners at close range, and the long-wavelength-sensitive opsin gene might be important for moth copulation (Yan et al.
Five classes of opsin genes encode visual pigments for dim-light and color vision.
We conducted a genetic analysis of one of the avian eye's short wave-length opsin receptors (SWS1, adapted from Odeen and Hastad 2003) to independently confirm the report of violet sensitivity in this species (Machovsky Capuska et al.
The opsin sequences have 364 amino acids divided into six exons separated by five 'neutral' segments or introns.
Arrestin-1 and arrestin-4, termed rod and cone arrestin, are expressed in photoreceptor cells and terminate rhodopsin and cone opsin signaling.
The researchers discovered this gene, for a protein called opsin, concentrated near chromatophores - tiny organs that consist of an elastic sac of red, yellow or black pigment tied to muscle fibres.
Color Vision: From Genes to Perception, chapter Opsin genes, cone photopigments, color vision, and color blindness, pages 3-51.
When light strikes rhodopsin, it immediately breaks down into two distinct compounds: the protein opsin and the carotenoid pigment retinal.
In GLE mice, the density of cone outer segments immunoreactive for middle- and short-wavelength-sensitive opsin was not significantly different from controls (Figure 1C; 15.
Phototransduction involves a conformational change in the chromophore and activation of an opsin.