Institute of Pharmacology and Toxicology, University of Zürich, 190 Winterthurerstrasse, Zürich 8057, Switzerland
Development. 2014 Aug;141(16):3105-11. doi: 10.1242/dev.104851.
A biological 'circadian' clock conveys diurnal regulation upon nearly all aspects of behavior and physiology to optimize them within the framework of the solar day. From digestion to cardiac function and sleep, both cellular and systemic processes show circadian variations that coincide with diurnal need. However, recent research has shown that this same timekeeping mechanism might have been co-opted to optimize other aspects of development and physiology that have no obvious link to the 24 h day. For example, clocks have been suggested to underlie heterogeneity in stem cell populations, to optimize cycles of cell division during wound healing, and to alter immune progenitor differentiation and migration. Here, I review these circadian mechanisms and propose that they could serve as metronomes for a surprising variety of physiologically and medically important functions that far exceed the daily timekeeping roles for which they probably evolved.
生物“生物钟”将昼夜节律调节作用传递给行为和生理的几乎所有方面，以在太阳日的框架内优化它们。从消化到心脏功能和睡眠，细胞和系统过程都表现出与昼夜需求相吻合的昼夜节律变化。然而，最近的研究表明，这种相同的计时机制可能被用来优化与 24 小时昼夜周期没有明显联系的其他发育和生理方面。例如，时钟被认为是干细胞群体异质性的基础，优化伤口愈合过程中的细胞分裂周期，并改变免疫祖细胞的分化和迁移。在这里，我回顾了这些生物钟机制，并提出它们可以作为生理和医学上重要功能的节拍器，这些功能远远超出了它们可能进化而来的日常计时作用。
