Report

Phototransduction by Retinal Ganglion Cells That Set the Circadian Clock

Science  08 Feb 2002:
Vol. 295, Issue 5557, pp. 1070-1073
DOI: 10.1126/science.1067262

You are currently viewing the abstract.

View Full Text
As a service to the community, AAAS/Science has made this article free with registration.

Abstract

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 blocked. The sensitivity, spectral tuning, and slow kinetics of this light response matched those of the photic entrainment mechanism, suggesting that these ganglion cells may be the primary photoreceptors for this system.

  • * To whom correspondence should be addressed. E-mail: David_Berson{at}brown.edu

  • These authors contributed equally to this work.

View Full Text

Cited By...