Institute of Feed Science, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Hangzhou, Zhejiang, China.
J Cell Biochem. 2019 Jun;120(6):9138-9146. doi: 10.1002/jcb.28189. Epub 2018 Dec 2.
In mammals, cold stress activates the cAMP-protein kinase A (PKA) signaling pathway, increases brown adipose tissue (BAT) activity, and induces thermogenesis to maintain body temperature. The cAMP responsive element binding protein (CREB)-regulated transcription coactivator 3 (CRTC3) plays important role in adipose development and energy metabolism. However, the effect of cold exposure on the intracellular localization of CRTC3 in BAT is unclear. Here, we report that cold-treated mice have higher expression of uncoupling protein 1 (UCP1) in adipose tissues and lower body weights and fat masses. Notably, cold exposure results in the nuclear translocation of CRTC3 in BAT. Moreover, forskolin (FSK), the activator of PKA pathway, induces the nuclear translocation of CRTC3 in brown adipocytes. At the molecular level, cold exposure and FSK treatment decrease liver kinase B1 (Lkb1) expression in brown adipocytes, which is related to the nuclear localization of CRTC3. These results demonstrate that the localization of CRTC3 involves in regulating cold-induced upregulation of UCP1 in BAT and provide useful information for understanding the molecular regulation of BAT thermogenesis induced by a cold environment.
在哺乳动物中,冷应激激活 cAMP-蛋白激酶 A(PKA)信号通路,增加棕色脂肪组织(BAT)的活性,并诱导产热以维持体温。环磷腺苷反应元件结合蛋白(CREB)调节转录共激活因子 3(CRTC3)在脂肪发育和能量代谢中发挥重要作用。然而,冷暴露对 BAT 中 CRTC3 的细胞内定位的影响尚不清楚。在这里,我们报告说,冷处理的小鼠在脂肪组织中具有更高的解偶联蛋白 1(UCP1)表达,并且体重和脂肪量更低。值得注意的是,冷暴露导致 BAT 中 CRTC3 的核转位。此外,PKA 途径的激活剂forskolin(FSK)诱导棕色脂肪细胞中 CRTC3 的核转位。在分子水平上,冷暴露和 FSK 处理降低了棕色脂肪细胞中肝激酶 B1(Lkb1)的表达,这与 CRTC3 的核定位有关。这些结果表明,CRTC3 的定位参与调节冷诱导的 BAT 中 UCP1 的上调,并为理解冷环境诱导的 BAT 产热的分子调节提供了有用信息。