Instructing the Pupils

Science's STKE  14 Jan 2003:
Vol. 2003, Issue 165, pp. tw24-TW24
DOI: 10.1126/stke.2003.165.tw24

The retinal pigment melanopsin is found in ganglion cells, which are downstream of the classic rods and cone photoreceptors of the visual system. By making knockout mice lacking melanopsin, Lucas et al. (see the Perspective by Menaker) show that this pigment likely responds directly to light to contribute to non-image-forming functions of the visual system, in particular the contraction of pupils to a sudden bright light.

R. J. Lucas, S. Hattar, M. Takao, D. M. Berson, R. G. Foster, K.-W. Yau, Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice. Science 299, 245-247 (2003). [Abstract] [Full Text]

M. Menaker, Circadian photoreception. Science 299, 213-214 (2003). [Summary] [Full Text]