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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.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biochemistry) the protein that together with retinene makes up the purple visual pigment rhodopsin
[C20: back formation from rhodopsin]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈɒp sɪn)

any of several compounds that form the protein component of the light-sensitive pigment rhodopsin.
[1950–55; probably back formation from rhodopsin]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Comparisons between the structures of opsin genes from Limulus (Fig.
Summary: TEHRAN (FNA)- Researchers have found that opsin 3 -- a protein closely related to rhodopsin, the protein that enables low-light vision -- has a role in adjusting the amount of pigment produced in human skin, a determinant of skin color.
Both rods and cones contain proteins known as opsins. While cones in human eyes have three kinds of opsins (called photopsin), rods only have one opsin known as rhodopsin.
Analysis of the genome has revealed many genes that encode proteins that would be expected to be integral to light signal transduction (Burke et al., 2006), including six opsin genes (Raible et al., 2006) and orthologs of mammalian retinal transcription factors (Agca et al., 2011).
X-linked cone dystrophy and colour vision deficiency arising from a missense mutation in a hybrid L/M cone opsin gene.
Nathans, "Opsin genes, cone photopigments, color vision, and color blindness," in Color Vision: From Genes to Perception, K.
In a molecular level, mature photoreceptors in human retina consist of three subtypes, rhodopsin + rods, L/M opsin + red/green cones, and S opsin + blue cones.
This viewpoint is only now evolving with our growing understanding of mammalian circadian photoreception in the retina and the important role of melanopsin [124], which is a short-wavelength (blue) sensitive opsin expressed by a subset of retinal ganglion cells that project directly to the SCN via the RHT.
This is caused by a mutation in the opsin gene, which is responsible for producing visual pigments for color vision. 
Opsin activation by photon capture requires the sensing molecule to be embedded in a lipid bilayer of optimal fluidity made of phospholipids rich in polyunsaturated fatty acids (PUFA) [61].