opsin


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Related to opsin: rhodopsin, opsonin, KIPRIS

op·sin

(op'sin),
The protein portion of the rhodopsin molecule; at least three separate opsins are located in cone cells.

opsin

/op·sin/ (op´sin) a protein of the retinal rods (scotopsin) and cones (photopsin) that combines with 11-cis -retinal to form visual pigments.

opsin

(ŏp′sĭn)
n.
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.

opsin

a protein that combines with retinal to form visual pigments (rhodopsin and iodopsin) in the photoreceptor cells of the retina.

op·sin

(op'sin)
The protein portion of the rhodopsin molecule; at least three separate opsins are located in cone cells.

opsin

a protein that occurs in rods and cones of the RETINA of the eye, which combines with retinal 1 or retinal2 to form visual pigments.

rhodopsin 

Visual pigment contained in the outer segments of the rod cells of the retina and involved in scotopic vision. When light stimulates the retina, the chromophore of the pigment molecule '11-cis' retinal (which is vitamin A aldehyde) isomerizes to 'all-trans' retinal. This leads to other chemical transformations which carry on even in the absence of light. The first stage is prelumirhodopsin, then lumirhodopsin and finally metarhodopsin (of which there are two types). This last transformation may lead to the breakdown of the molecule into retinal and opsin. The molecule is regenerated by recombining retinal and opsin with some enzymes. The absorption spectrum of rhodopsin has a maximum around 498 nm. The isomerization from '11-cis' to 'all-trans' also gives rise to the process of transduction in which the membrane potential covering the pigment molecules in the outer segment changes towards a hyperpolarization of the cell. This is the first step in the nervous response to a light stimulation of the retina. Syn. visual purple (not used any more); erythropsin. See dark adaptation; bleaching; receptor potential; absorption spectrum; transduction.

opsin (op´sin),

n a visual pigment protein found in the retinal rods.

opsin

the protein component of retinal pigments, e.g. rhodopsin.
References in periodicals archive ?
Opsins operating beyond the eyes might offer local refinements to camouflage or even help the animals sense other environmental cues such as pressure.
Complex distribution of avian color vision systems revealed by sequencing the SWSI opsin from total DNA.
Mathger thinks the presence of opsin may mean that the otherwise colourblind cuttlefish can "see" a multicoloured environment through their skin.
Louis, MO Glyceraldehyde Protein loading Mouse MAB 374; 1:300 3-phosphate control Millipore, dehydrogenase Billerica, MA Ki67 Progenitor cell Mouse 500609; BD, 1:100 marker Franklin Lakes, NJ Opsins (middle- Cones Rabbit Gifts from C.
Hunt, "The Evolution of Trichromatic Color Vision by Opsin Gene Duplication in New World and Old World Primates," Genome Research 9 (1999): 629-38.
Vertebrates use ciliary opsin in photoreceptor cells, whereas invertebrates use rhabdomeric opsin.
Now the researchers must definitively connect VA opsin to body clocks in mammals, including people.
The molecules of the opsin family are extremely sensitive to quantities of light that have been already shown in studies decades ago to penetrate all the way into central parts of the brain", he emphasizes.
Just two light-sensing pigments of the opsin type, one tuned to greenish and the other to a blue wavelength, would be enough to detect such a shift, the researchers calculate.
5) The [lambda]max of the photopigment's spectral sensitivity curve is determined by the amino acid sequence of the opsin and the relationship of the opsin with the chromophore.
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.