在PKGIa中的氨酸氧化还原传感器使氧化剂诱导的激活成为可能
Joseph R Burgoyne1, Melanie Madhani, Friederike Cuello
1Department of Cardiology, Cardiovascular Division, King's College London, Rayne Institute, St. Thomas' Hospital, London SE1 7EH, UK.
概括
关利基环酶依赖蛋白激酶 (PKG) 作为一个氧化还原传感器. 氧化激活PKG,增强基质亲和力和调节细胞功能,独立于氧化和cGMP.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 生理学 生理学 生理学
背景情况:
- 细胞氧化剂水平通过生物化学信号调节细胞功能.
- 关利基环酶依赖蛋白激酶 (PKG) 是一个关键的信号酶.
- 氧化 (NO) 和循环氨酸单酸盐 (cGMP) 是PKG的经典激活剂.
研究的目的:
- 调查PKG是否可以作为直接的氧化还原传感器.
- 阐明通过氧化剂激活PKG的分子机制.
- 探索氧化剂介导PKG激活的生理相关性.
主要方法:
- 细胞和组织暴露于过氧化.
- 在PKGIalpha中对蛋白间二硫化键形成的分析.
- 在体外激酶测试以评估活性和基质亲和力.
- 在老鼠细胞和组织上的研究.
主要成果:
- 在暴露于过氧化时,PKGIalpha异型在其子单元之间形成蛋白间二硫化键.
- 这种氧化直接激活PKGIalpha激酶活性.
- 二硫化物形成增强了PKGIalpha对其基质的亲和力.
- 氧化剂诱导的PKG激活独立于NO/cGMP通路发生.
结论:
- PKG直接感知细胞氧化剂,作为氧化还原传感器起作用.
- 氧化诱导的PKG激活提供了一个cGMP独立的调节机制.
- 这种途径解释了氧化剂介导的血管松和过氧化作为内皮衍生的高极化因子的作用.
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