Life evolved in the presence of alternating periods of light and dark that accompany the daily rotation of the Earth on its axis. This offered an advantage for organisms able to regulate their physiology to anticipate these daily cycles. In each light-sensitive organism studied, spanning single-celled bacteria to complex mammals, there exist timekeeping mechanisms able to control physiology over the course of 24 hours. Endowed with internal timekeeping, organisms can put their previously stored energy to the most efficient use, selectively ramping up biological processes at specific times of day or night according to when they will be needed. Humans have evolved to be more active during the day (diurnal), likely due to the increased opportunities for foraging or hunting in our evolutionary past, and this daily activity is accompanied by an up-regulation of genes involved in metabolism to increase the energy available for such behaviours. Remarkably, this happens without conscious thought—due to a complex organism-wide signalling apparatus known as the circadian clock network, which conveys time information between cells and tissues.
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April 08 2020
Clock-in, clock-out: circadian timekeeping between tissues
Jacob G. Smith;
Jacob G. Smith
1University of California, Irvine, USA
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Paolo Sassone-Corsi
Paolo Sassone-Corsi
1University of California, Irvine, USA
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Publisher: Portland Press Ltd
Online ISSN: 1740-1194
Print ISSN: 0954-982X
2020 © The Authors.
2020
Published by Portland Press Limited under the Creative Commons Attribution License 4.0 (CC BY-NC-ND)
Biochem (Lond) (2020) 42 (2): 6–10.
Citation
Jacob G. Smith, Paolo Sassone-Corsi; Clock-in, clock-out: circadian timekeeping between tissues. Biochem (Lond) 1 April 2020; 42 (2): 6–10. doi: https://doi.org/10.1042/BIO04202007
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