CIRCADIAN RHYTHMS Prisoners of the Light

The circadian behavior of mammals is regulated by two transcription factors, CLOCK and NPAS2, that are related in sequence but differ in expression patterns. Dudley et al. (see Perspective by Green and Menaker) found that NPAS2-deficient mice have abnormal sleep patterns during the night and, in contrast to wild-type mice, were unable to adapt to changes in feeding schedule. This phenotype that suggests their circadian behavior was dictated primarily by the light-dark cycle. These results are consistent with a model in which CLOCK is used for light-controlled rhythms and NPAS2 for sensory-controlled rhythms such as feeding. This duality may allow mammals to be more adaptable to changing environmental conditions.

C. A. Dudley, C. Erbel-Sieler, S. J. Estill, M. Reick, P. Franken, S. Pitts, S. L. McKnight, Altered patterns of sleep and behavioral adaptability in NPAS2-deficient mice. Science 301, 379-383 (2003). [Abstract] [Full Text]

C. B. Green, M. Menaker, Clocks on the brain. Science 301, 319-320 (2003). [Summary] [Full Text]

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REPORTS
Altered Patterns of Sleep and Behavioral Adaptability in NPAS2-Deficient Mice

Carol A. Dudley, Claudia Erbel-Sieler, Sandi Jo Estill, Martin Reick, Paul Franken, SiNae Pitts, and Steven L. McKnight (18 July 2003)
Science 301 (5631), 379. [DOI: 10.1126/science.1082795]
 |  Abstract »  |  Full Text »  |  PDF »  |  Supporting Online Material »

PERSPECTIVES
CIRCADIAN RHYTHMS:
Clocks on the Brain

Carla B. Green and Michael Menaker (18 July 2003)
Science 301 (5631), 319. [DOI: 10.1126/science.1087824]
 |  Summary »  |  Full Text »  |  PDF »