melanopsin


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Related to melanopsin: photopigment

melanopsin

An opsin-like protein, sensitive to light with a peak sensitivity around 480 nm, and found in the very small proportion of retinal ganglion cells which are photosensitive. It is believed to be the visual pigment that synchronizes the circadian cycle to the day-night cycle as well as being involved in the control of pupil size and the release of melatonin. This neural circuit appears to be independent of the conventional retinal phototransduction in the rods and cones. See pupil light reflex.
References in periodicals archive ?
Melyan et al., "Evolution of melanopsin photoreceptors: discovery and characterization of a new melanopsin in nonmammalian vertebrates," PLoS Biology, vol.
Since corals express rhodopsins and melanopsins (Anctil et al., 2007; Vize, 2009), which are classic visual and nonvisual photoreceptors that act via calcium second messengers in many marine invertebrates (Yarfitz and Hurley, 1994; Vize, 2009), this is more likely to be the mechanism responsible for sensing and responding to light in coral.
The left eye of each animal was intravitreally injected with different doses of immunotoxin melanopsin-SAP (2 [micro]l/eye) (Advanced Targeting Systems, San Diego, CA, USA), consisting of saporin conjugated to a melanopsin polyclonal antibody.
"Until now, the role of retinal melanopsin cells and how they contribute to the perception of the brightness of light have been unclear," said Katsunori Okajima, a professor at the Faculty of Environment and Information Sciences, Yokohama National University and one of the authors of the study.
In the new work, the Salk researchers used molecular tools to turn on production of melanopsin in retinal cells in mice.
The evolution of irradiance detection: melanopsin and the non-visual opsins.
[8.] Gooley JJ, Lu J, Chou TC, Scammell TE, Saper CB (2001) Melanopsin in cells of origin of the retinohypothalamic tract.
Melanopsin retinal ganglion cell loss in Alzheimer disease.
Carlson et al., "Induction of photosensitivity by heterologous expression of melanopsin," Nature, vol.
Zhao, "Melanopsin retinal ganglion cell loss and circadian dysfunction in Alzheimer's disease (review)," Molecular Medicine Reports, vol.