Skip to main content

Opsin References

receptorsignallingphysiologicaltransductioncircadian rhythmspupillaryreflexwavelengthteleostreptilesbirdsmammalsOld World monkeysapeshumanstrichromacyevolution of colour visionMesozoicnocturnal






Open main menu



Wikipedia









Opsin











function mfTempOpenSection(id)var block=document.getElementById("mf-section-"+id);block.className+=" open-block";block.previousSibling.className+=" open-block";


Opsins are the universal photoreceptor molecules of all visual systems in the animal kingdom.[1][2]


They change from a resting state to a signalling state by absorbing light. This activates the G protein, resulting in a signalling cascade which produces physiological responses.


This process of capturing a photon and transforming it into a physiological response is known as phototransduction.


Five groups of opsins are involved in vision. Another opsin found in the mammalian retina, melanopsin, is involved in circadian rhythms and pupillary reflex, but not in image-forming.[3]


Some opsins allows vision in just a short stretch of wavelength. This is equivalent to seeing in only one colour. Two opsins allow vision in two colours, and is usual in mammals. Four opsins allows vision in full colour, and is usual in teleost fish, reptiles and birds. In mammals, only Old World monkeys, apes and humans have trichromacy, full colour vision.


It is thought – see evolution of colour vision – that mammals lost much of their colour vision capability during the long period in the Mesozoic when they lived as mostly nocturnal animals.[4]


"...two cone opsin gene families appear in contemporary eutherian mammals and, with the exception of some primates, none of these animals derive more than a single photopigment type from each of their two gene families".[5][6]



References





  1. Plachetzki, D.; Fong, C.; Oakley T. 2010. "The evolution of phototransduction from an ancestral cyclic nucleotide gated pathway". Proceedings of the Royal Society / Biological sciences 277 (1690): 1963–1969. doi:10.1098/rspb.2009.1797. PMID 20219739.


  2. Shichida Y.; Matsuyama T. 2009. "Evolution of opsins and phototransduction". [1] Philosophical transactions of the Royal Society of London. Series B, Biological sciences. 364 (1531): 2881–2895. doi:10.1098/rstb.2009.0051. PMID 19720651


  3. Lamb T.D; Collin S.P. & Pugh E.N. Jr. 2007. Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup. Nature Reviews Neuroscience. 8 (12): 960–976. [2]


  4. Kemp T.S. 2005. The origin and evolution of mammals. Oxford University Press.


  5. Bowmaker J.K. 1998. Evolution of colour vision in vertebrates. Eye 12 (3b): 541–547. [3]


  6. Jacobs G.H. 2009. Phil Trans Roy Soc B. 364 (1531) 2957-2967. [4]











Retrieved from "https://simple.wikipedia.org/w/index.php?title=Opsin&oldid=5874207"











Wikipedia


Content is available under CC BY-SA 3.0 unless otherwise noted.








(RLQ=window.RLQ||[]).push(function()mw.config.set("wgPageParseReport":"limitreport":"cputime":"0.032","walltime":"0.042","ppvisitednodes":"value":146,"limit":1000000,"ppgeneratednodes":"value":0,"limit":1500000,"postexpandincludesize":"value":299,"limit":2097152,"templateargumentsize":"value":69,"limit":2097152,"expansiondepth":"value":7,"limit":40,"expensivefunctioncount":"value":0,"limit":500,"unstrip-depth":"value":0,"limit":20,"unstrip-size":"value":3099,"limit":5000000,"entityaccesscount":"value":0,"limit":400,"timingprofile":["100.00% 24.998 1 Template:Reflist","100.00% 24.998 1 -total"," 15.14% 3.784 1 Template:Main_other"],"scribunto":"limitreport-timeusage":"value":"0.002","limit":"10.000","limitreport-memusage":"value":531657,"limit":52428800,"cachereport":"origin":"mw1274","timestamp":"20190801090817","ttl":2592000,"transientcontent":false););"@context":"https://schema.org","@type":"Article","name":"Opsin","url":"https://simple.wikipedia.org/wiki/Opsin","sameAs":"http://www.wikidata.org/entity/Q416877","mainEntity":"http://www.wikidata.org/entity/Q416877","author":"@type":"Organization","name":"Contributors to Wikimedia projects","publisher":"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":"@type":"ImageObject","url":"https://www.wikimedia.org/static/images/wmf-hor-googpub.png","datePublished":"2011-01-17T18:20:12Z","dateModified":"2017-11-12T00:59:20Z"(window.NORLQ=window.NORLQ||[]).push(function()var ns,i,p,img;ns=document.getElementsByTagName('noscript');for(i=0;i-1)img=document.createElement('img');img.setAttribute('src',p.getAttribute('data-src'));img.setAttribute('width',p.getAttribute('data-width'));img.setAttribute('height',p.getAttribute('data-height'));img.setAttribute('alt',p.getAttribute('data-alt'));p.parentNode.replaceChild(img,p);});(RLQ=window.RLQ||[]).push(function()mw.config.set("wgBackendResponseTime":82,"wgHostname":"mw1248"););

Popular posts from this blog

Category:9 (number) SubcategoriesMedia in category "9 (number)"Navigation menuUpload mediaGND ID: 4485639-8Library of Congress authority ID: sh85091979ReasonatorScholiaStatistics

Circuit construction for execution of conditional statements using least significant bitHow are two different registers being used as “control”?How exactly is the stated composite state of the two registers being produced using the $R_zz$ controlled rotations?Efficiently performing controlled rotations in HHLWould this quantum algorithm implementation work?How to prepare a superposed states of odd integers from $1$ to $sqrtN$?Why is this implementation of the order finding algorithm not working?Circuit construction for Hamiltonian simulationHow can I invert the least significant bit of a certain term of a superposed state?Implementing an oracleImplementing a controlled sum operation

Magento 2 “No Payment Methods” in Admin New OrderHow to integrate Paypal Express Checkout with the Magento APIMagento 1.5 - Sales > Order > edit order and shipping methods disappearAuto Invoice Check/Money Order Payment methodAdd more simple payment methods?Shipping methods not showingWhat should I do to change payment methods if changing the configuration has no effects?1.9 - No Payment Methods showing upMy Payment Methods not Showing for downloadable/virtual product when checkout?Magento2 API to access internal payment methodHow to call an existing payment methods in the registration form?