Circadian rhythms from flies to human


In this era of jet travel, our body 'remembers' the previous time zone, such that when we travel, our sleep–wake pattern, mental alertness, eating habits and many other physiological processes temporarily suffer the consequences of time displacement until we adjust to the new time zone. Although the existence of a circadian clock in humans had been postulated for decades, an understanding of the molecular mechanisms has required the full complement of research tools. To gain the initial insights into circadian mechanisms, researchers turned to genetically tractable model organisms such as Drosophila.

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Figure 1: Assay of circadian activity rhythm in flies and mice.
Figure 2: Schematic diagrams showing anatomic features of Drosophila and rodent central oscillator.
Figure 3: Drosophila and mammalian circadian clock.


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Correspondence to Steve A. Kay.

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Panda, S., Hogenesch, J. & Kay, S. Circadian rhythms from flies to human. Nature 417, 329–335 (2002).

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