The central pacemaker in the hypothalamic suprachiasmatic nucleus (SCN) synchronizes peripheral oscillators to coordinate physiological and behavioural activities throughout the body. How circadian phase coherence between the SCN and the periphery is controlled is not well understood. Here, we identify hepatic SIRT7 as an early responsive element to light that ensures circadian phase coherence in the mouse liver. The SCN-driven body temperature (BT) oscillation induces rhythmic expression of HSP70, which promotes SIRT7 ubiquitination and proteasomal degradation. Acute temperature challenge dampens the BT oscillation and causes an advanced liver circadian phase. Further, hepatic SIRT7 deacetylates CRY1, promotes its FBXL3-mediated degradation and regulates the hepatic clock and glucose homeostasis. Loss of Sirt7 in mice leads to an advanced liver circadian phase and rapid entrainment of the hepatic clock upon daytime-restricted feeding. These data identify a BT–HSP70–SIRT7–CRY1 axis that couples the mouse hepatic clock to the central pacemaker and ensures circadian phase coherence and glucose homeostasis.

下丘脑视交叉上核 (SCN) 中的中央起搏器同步外周振荡器以协调整个身体的生理和行为活动。如何控制 SCN 和外围之间的昼夜相位相干性尚不清楚。在这里，我们将肝脏 SIRT7 确定为对光的早期反应元件，可确保小鼠肝脏的昼夜节律相干性。SCN 驱动的体温 (BT) 振荡诱导 HSP70 的节律性表达，从而促进 SIRT7 泛素化和蛋白酶体降解。急性温度挑战会抑制 BT 振荡并导致肝脏昼夜节律阶段提前。此外，肝脏 SIRT7 使 CRY1 去乙酰化，促进其 FBXL3 介导的降解并调节肝脏时钟和葡萄糖稳态。Sirt7的丢失在小鼠中，白天限制进食会导致肝脏昼夜节律阶段提前和肝脏时钟快速夹带。这些数据确定了一个 BT-HSP70-SIRT7-CRY1 轴，它将小鼠肝时钟与中央起搏器耦合，并确保昼夜节律相干性和葡萄糖稳态。