Smoothened的刺信号活动需要由蛋白激酶A和素激酶I进行酸化
Jianhang Jia1, Chao Tong, Bing Wang
1Center for Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA. jin.jiang@utsouthwestern.edu
Nature
|December 24, 2004
概括
蛋白激酶A (PKA) 和氨酸激酶I (CKI) 通过酸化光滑化 (Smo) 来调节刺 (Hh) 信号. 这种酸化控制了Smo细胞表面积累和动物发育过程中的通路活动.
科学领域:
- 发展生物学 发展生物学
- 细胞信号传递 细胞信号传递
- 分子生物学分子生物学
背景情况:
- 刺 (Hh) 信号通路对动物发育至关重要,控制细胞生长和模式.
- Hh信号传导依赖于七个跨膜蛋白质Smo,但其调节机制尚未完全理解.
研究的目的:
- 阐明控制平滑 (Smo) 细胞表面积累和响应 (Hh) 信号的活性的调节机制.
- 研究蛋白激酶A (PKA) 和素激酶I (CKI) 在Hh通路调节中的作用.
主要方法:
- 使用了Drosophila翅膀盘模型系统.
- 研究了PKA和CKI活性调节对Smo细胞表面积累和Hh通路活性的影响.
- 通过特定位点突变 (酸化缺陷和酸化模仿变体) 分析了Smo蛋白酸化.
主要成果:
- 确定PKA和CKI是Smo细胞表面积累和活动的关键调节者.
- 抑制PKA或CKI损害了Drosophila翅膀盘中的Hh诱导的Smo积累和通路活性.
- 相反,增加的PKA活性增强了Smo积累和通路激活.
- PKA和CKI在多个部位直接化Smo,这对其细胞表面定位和信号功能至关重要.
- 缺乏酸化的Smo突变体未能在细胞表面积累并转化Hh信号.
- 模仿酸化的Smo突变体表现出构成性细胞表面表达和信号.
结论:
- 刺 (Hh) 信号诱导了PKA和CKI的Smo.逐渐酸化.
- 这种酸化事件对于提高Smo细胞表面水平和激活Hh通路至关重要.
- PKA和CKI代表HH信号级联中的关键监管节点,控制Smo的本地化和功能.
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