细胞生物学
转录因子
转录调控
抄写(语言学)
化学
基因表达调控
作者
Sunmi Seok,Ting Fu,Sung E. Choi,Yang Li,Rong Zhu,Subodh Kumar,Xiaoxiao Sun,Gyesoon Yoon,Yup Kang,Wenxuan Zhong,Jian Ma,Byron Kemper,Jongsook Kim Kemper
出处
期刊:Nature
[Springer Nature]
日期:2014-12-04
卷期号:516 (7529): 108-111
被引量:264
摘要
Lysosomal degradation of cytoplasmic components by autophagy is essential for cellular survival and homeostasis under nutrient-deprived conditions. Acute regulation of autophagy by nutrient-sensing kinases is well defined, but longer-term transcriptional regulation is relatively unknown. Here we show that the fed-state sensing nuclear receptor farnesoid X receptor (FXR) and the fasting transcriptional activator cAMP response element-binding protein (CREB) coordinately regulate the hepatic autophagy gene network. Pharmacological activation of FXR repressed many autophagy genes and inhibited autophagy even in fasted mice, and feeding-mediated inhibition of macroautophagy was attenuated in FXR-knockout mice. From mouse liver chromatin immunoprecipitation and high-throughput sequencing data, FXR and CREB binding peaks were detected at 178 and 112 genes, respectively, out of 230 autophagy-related genes, and 78 genes showed shared binding, mostly in their promoter regions. CREB promoted autophagic degradation of lipids, or lipophagy, under nutrient-deprived conditions, and FXR inhibited this response. Mechanistically, CREB upregulated autophagy genes, including Atg7, Ulk1 and Tfeb, by recruiting the coactivator CRTC2. After feeding or pharmacological activation, FXR trans-repressed these genes by disrupting the functional CREB-CRTC2 complex. This study identifies the new FXR-CREB axis as a key physiological switch regulating autophagy, resulting in sustained nutrient regulation of autophagy during feeding/fasting cycles.
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