Department of Biology, University of Virginia, Charlottesville, VA 22904, USA.
Program in Fundamental Neuroscience, Charlottesville, VA 22904, USA.
Sci Adv. 2023 Aug 25;9(34):eadh9570. doi: 10.1126/sciadv.adh9570.
Salient cues, such as the rising sun or availability of food, entrain biological clocks for behavioral adaptation. The mechanisms underlying entrainment to food availability remain elusive. Using single-nucleus RNA sequencing during scheduled feeding, we identified a dorsomedial hypothalamus leptin receptor-expressing (DMH) neuron population that up-regulates circadian entrainment genes and exhibits calcium activity before an anticipated meal. Exogenous leptin, silencing, or chemogenetic stimulation of DMH neurons disrupts the development of molecular and behavioral food entrainment. Repetitive DMH neuron activation leads to the partitioning of a secondary bout of circadian locomotor activity that is in phase with the stimulation and dependent on an intact suprachiasmatic nucleus (SCN). Last, we found a DMH neuron subpopulation that projects to the SCN with the capacity to influence the phase of the circadian clock. This direct DMH-SCN connection is well situated to integrate the metabolic and circadian systems, facilitating mealtime anticipation.
明显的线索,如升起的太阳或食物的可获得性,使生物钟适应行为。食物可获得性的同步机制仍然难以捉摸。在预定的喂食过程中使用单细胞 RNA 测序,我们确定了一个表达瘦素受体的下丘脑背内侧(DMH)神经元群体,该群体在预期的餐前上调昼夜节律同步基因并表现出钙活性。外源性瘦素、DMH 神经元的沉默或化学遗传刺激会破坏分子和行为食物同步的发展。DMH 神经元的重复激活导致与刺激同步且依赖于完整的视交叉上核(SCN)的第二波昼夜节律性运动活动的分区。最后,我们发现了一个 DMH 神经元亚群,它投射到 SCN,具有影响生物钟相位的能力。这种直接的 DMH-SCN 连接非常适合整合代谢和昼夜节律系统,促进进餐时间的预期。