克雷布联合激活器TORC2作为一种对和cAMP敏感的巧合探测器
Robert A Screaton1, Michael D Conkright, Yoshiko Katoh
1Peptide Biology Laboratories, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
Cell
|September 30, 2004
概括
营养和肠道激素通过激活CREB来增强胰腺小岛细胞功能. 一个涉及氨酸和SIK2的新型信号模块控制TORC2,一个CREB联合激活器,将这些通路连接到基因表达.
科学领域:
- 细胞信号通道是细胞信号通道.
- 内分泌学 在内分泌学.
- 分子生物学分子生物学
背景情况:
- 胰腺小岛细胞活力是由葡萄糖和肠道激素促进的.
- 和cAMP信号通路激活了转录因子CREB.
研究的目的:
- 阐明一个信号模块介导和cAMP对基因表达的协同效应.
- 确定 TORC2 的作用,一个 CREB 协活性剂,在营养和激素信号传递中.
主要方法:
- 研究了素素,SIK2和TORC2.2之间的相互作用.
- 分析了TORC2与14-3-3蛋白的酸化依赖相互作用.
- 研究了和cAMP对TORC2脱和核进入的影响.
主要成果:
- 一个涉及氨酸和SIK2的信号模块将和cAMP通路连接到TORC2.2.
- 增加了氨酸的活性,促进了TORC2脱化.
- cAMP抑制SIK2激酶活性,也导致TORC2脱和进入核.
结论:
- 一个酸酶/激酶模块将营养和激素线索与CREB联合激活器TORC2.2联系起来.
- 这个模块调节胰腺小岛细胞中的基因表达.
- 破坏TORC2:14-3-3复合体是营养刺激信号的关键.
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