Institute for Theoretical Biology, Humboldt-Universität zu Berlin, Philippstr. 13, 10115, Berlin, Germany.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2024 Jul;210(4):549-564. doi: 10.1007/s00359-023-01669-z. Epub 2023 Sep 2.
Circadian clocks are internal timing devices that have evolved as an adaption to the omnipresent natural 24 h rhythmicity of daylight intensity. Properties of the circadian system are photoperiod dependent. The phase of entrainment varies systematically with season. Plastic photoperiod-dependent re-arrangements in the mammalian circadian core pacemaker yield an internal representation of season. Output pathways of the circadian clock regulate photoperiodic responses such as flowering time in plants or hibernation in mammals. Here, we review the concepts of seasonal entrainment and photoperiodic encoding. We introduce conceptual phase oscillator models as their high level of abstraction, but, yet, intuitive interpretation of underlying parameters allows for a straightforward analysis of principles that determine entrainment characteristics. Results from this class of models are related and discussed in the context of more complex conceptual amplitude-phase oscillators as well as contextual molecular models that take into account organism, tissue, and cell-type-specific details.
昼夜节律钟是一种内在的计时装置，是为了适应无处不在的自然 24 小时光照强度的周期性变化而进化而来的。昼夜节律系统的特性依赖于光周期。驯化的相位随季节系统地变化。哺乳动物昼夜节律核心起搏器中的光周期依赖性可塑重新排列产生了季节的内部表现。昼夜节律钟的输出途径调节光周期反应，如植物的开花时间或哺乳动物的冬眠。在这里，我们回顾了季节性驯化和光周期编码的概念。我们引入了概念相振荡器模型，因为它们具有高度的抽象性，但对底层参数的直观解释使得对决定驯化特性的原理进行直接分析成为可能。从这一类模型中得到的结果与更复杂的概念幅度-相位振荡器以及考虑到生物体、组织和细胞类型特异性细节的上下文分子模型相关，并在其中进行了讨论。
