Phototransduction by Retinal Ganglion Cells That Set the Circadian Clock

@article{Berson2002PhototransductionBR,
  title={Phototransduction by Retinal Ganglion Cells That Set the Circadian Clock},
  author={David M. Berson and Felice A. Dunn and M. Takao},
  journal={Science},
  year={2002},
  volume={295},
  pages={1070 - 1073}
}
Light synchronizes mammalian circadian rhythms with environmental time by modulating retinal input to the circadian pacemaker—the suprachiasmatic nucleus (SCN) of the hypothalamus. Such photic entrainment requires neither rods nor cones, the only known retinal photoreceptors. Here, we show that retinal ganglion cells innervating the SCN are intrinsically photosensitive. Unlike other ganglion cells, they depolarized in response to light even when all synaptic input from rods and cones was… 

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