Melanopsin: an exciting photopigment

@article{Hankins2008MelanopsinAE,
  title={Melanopsin: an exciting photopigment},
  author={Mark W. Hankins and Stuart N. Peirson and Russell G. Foster},
  journal={Trends in Neurosciences},
  year={2008},
  volume={31},
  pages={27-36}
}
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382 Citations
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382 Citations

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This review discusses the history of discovery for the vertebrate ancient (va) opsin and melanopsin genes, as well as focusing on the evolution, expression profile, functional role and broader physiological significance of each photopigment.

The Evolution and Function of Melanopsin in Craniates

The evolutionary history of the melanopsin gene, its diverse patterns of expression and transcriptional output, the functional roles so far determined, and the clinical significance of this critical and phylogenetically most ancient opsin-based system of irradiance detection are discussed.

MELANOPSIN PHOTOPIGMENT, LIGHT PHOTOTRANSDUCTION PATHWAY, AND PIGMENT REGENERATION

The structural relationship of melanopsin to invertebrate opsins provides clues to its evolutionary origin, and suggests that its function as a light sensitive pigment is likely different than classic visual photopigments in rod and cone photoreceptors.

Genetic Advances in Ophthalmology: The Role of Melanopsin-Expressing, Intrinsically Photosensitive Retinal Ganglion Cells in the Circadian Organization of the Visual System

This review will cover the role that melanopsin and ipRGCs play in the circadian organization of the visual system and note that both central and peripheral oscillators share an endogenous, circadian-driven, transcription–translation feedback loop that cycles with a periodicity of approximately 24 hours.

The active site of melanopsin: the biological clock photoreceptor.

These findings, analogous to spectral changes observed in the G89Q bovine rhodopsin mutant, suggest that single site mutations can convert photopigments into visual light sensors or nonvisual sensory photoreceptors.

Phototransduction and the Evolution of Photoreceptors

...

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