Melanopsin and rod–cone photoreceptive systems account for all major accessory visual functions in mice

@article{Hattar2003MelanopsinAR,
  title={Melanopsin and rod–cone photoreceptive systems account for all major accessory visual functions in mice},
  author={Samer Hattar and Robert James Lucas and Nicholas Mrosovsky and Stewart Thompson and Ronald H. Douglas and M. W. Hankins and Janis Lem and Martin Biel and Franz Hofmann and Russell G. Foster and King-Wai Yau},
  journal={Nature},
  year={2003},
  volume={424},
  pages={75-81}
}
In the mammalian retina, besides the conventional rod–cone system, a melanopsin-associated photoreceptive system exists that conveys photic information for accessory visual functions such as pupillary light reflex and circadian photo-entrainment. On ablation of the melanopsin gene, retinal ganglion cells that normally express melanopsin are no longer intrinsically photosensitive. Furthermore, pupil reflex, light-induced phase delays of the circadian clock and period lengthening of the circadian… 

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