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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 ?
The LpUVOps1-expressing ME photoreceptors and LE eccentric cells are the only retinal neurons in which opsin coexpression has not been detected
14) In the normal functioning retina vitamin A is transported from Bruch's membrane to reach the retinal pigment epithelium (RPE) where it is converted to 11-cis retinal and combines with the protein opsin which ultimately forms rhodopsin in the photoreceptor outer segments (see Figure 4, page 70).
And the light-sensitive opsin proteins in the eyes aren't typical eye compounds, Bok is finding.
The researchers verified the function of the light response pathway by mutating an opsin gene in mice called Opn4 that produces melanopsin, in essence preventing activation of the photo pigment.
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.
Thus, Snoke has his own "Adamic memory" problem with an equally deceptive God, in which God makes the human green opsin gene appear to be 5.
Because this opsin is expressed in two distinct cell types, we believe there are rod and cone specific promoter elements driving expression in each cell.
Available transcriptomic data provide us with some initial glimpses into spider opsin evolution.
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.
The opsin sequences have 364 amino acids divided into six exons separated by five 'neutral' segments or introns.