How does the circadian clock send timing information to the brain?
This paper discusses circadian output in terms of the signaling mechanisms used by circadian pacemaker neurons. In mammals, the suprachiasmatic nucleus houses a clock controlling several rhythmic events. This nucleus contains one or more pacemaker circuits, and exhibits diversity in transmitter content and in axonal projections. In Drosophila, a comparable circadian clock is located among period -expressing neurons, a sub-set of which (called LN-vs) express the neuropeptide PDF. Genetic experiments indicate LN-vs are the primary pacemakers neurons controlling daily locomotion and that PDF is the principal circadian transmitter. Further definition of pacemaker properties in several model systems will provide a useful basis with which to describe circadian output mechanisms.
Taghert
P H
PH
Department of Anatomy & Neurobiology, Box 8108, Washington University School of Medicine, 660 South Euclid Avenue, Saint Louis, MO 63110, USA. taghertp@pcg.wustl.edu
D000818:Animals; D001683:Biological Clocks / Q000235:genetics / Q000502:physiology; D001921:Brain / Q000502:physiology*; D002940:Circadian Rhythm; D004330:Drosophila / Q000235:genetics / Q000502:physiology; D029721:Drosophila Proteins; D015870:Gene Expression; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D008322:Mammals; D009474:Neurons / Q000502:physiology; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013493:Suprachiasmatic Nucleus / Q000502:physiology*; D014667:Vasopressins / Q000235:genetics / Q000502:physiology
D029721:Drosophila Proteins; D019476:Insect Proteins; D009479:Neuropeptides; C113883:pdf protein, Drosophila; D014667:Vasopressins