{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T00:55:11Z","timestamp":1789779311029,"version":"4.0.1"},"reference-count":63,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,4,26]],"date-time":"2023-04-26T00:00:00Z","timestamp":1682467200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Ophthalmol."],"abstract":"<jats:p>Melanopsin is a light-activated G protein coupled receptor that is expressed widely across phylogeny. In mammals, melanopsin is found in intrinsically photosensitive retinal ganglion cells (ipRGCs), which are especially important for \u201cnon-image\u201d visual functions that include the regulation of circadian rhythms, sleep, and mood. Photochemical and electrophysiological experiments have provided evidence that melanopsin has at least two stable conformations and is thus multistable, unlike the monostable photopigments of the classic rod and cone photoreceptors. Estimates of melanopsin\u2019s properties vary, challenging efforts to understand how the molecule influences vision. This article seeks to reconcile disparate views of melanopsin and offer a practical guide to melanopsin\u2019s complexities.<\/jats:p>","DOI":"10.3389\/fopht.2023.1174255","type":"journal-article","created":{"date-parts":[[2023,4,26]],"date-time":"2023-04-26T05:58:30Z","timestamp":1682488710000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":11,"title":["The multistable melanopsins of mammals"],"prefix":"10.3389","volume":"3","author":[{"given":"Alan J.","family":"Emanuel","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael Tri H.","family":"Do","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2023,4,26]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1098\/rstb.2009.0051","article-title":"Evolution of opsins and 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