在线粒体中解码细胞质振荡的解码
G Hajnóczky1, L D Robb-Gaspers, M B Seitz
1Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Cell
|August 11, 1995
概括
线粒体对振荡的频率做出反应,而不仅仅是它们的水平. 这种依赖频率的信号控制着线粒体代谢和细胞中的酶活性.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 生理学 生理学 生理学
背景情况:
- 细胞质 ([Ca2+]c) 振荡对于信号传导至关重要.
- 直接将[Ca2+]c振荡与Ca2+) 规范的目标联系起来是一项挑战.
- 线粒体在细胞平衡和新陈代谢中发挥着关键作用.
研究的目的:
- 研究 mitochondrial Ca(2+) 敏感脱酶 (CSMDHs) 是如何被细胞质 ([Ca2+]c) 振荡所控制的.
- 为了将线粒体Ca(2+) ([Ca2+]m) 动态与细胞代谢活动相关联.
- 为了确定不同[Ca2+]c振荡模式对线粒体功能的影响.
主要方法:
- 在单个肝细胞中同时监测[Ca2+]c,线粒体Ca2+ ([Ca2+]m) 和黄蛋白/皮里丁核酸氧化还原状态.
- 使用IP3依赖激素诱导[Ca2+]c振荡.
- 对CSMDH活动的分析,以响应不同的[Ca2+]c和[Ca2+]m信号.
主要成果:
- 由IP3依赖的激素诱导的[Ca2+]c振荡被有效地作为[Ca2+]m振荡传递到线粒体.
- [Ca2+]m尖峰最大限度地激活了CSMDHs.
- [Ca2+]m每分钟高于0.5的振荡持续了线粒体新陈代谢.
- 持续[Ca2+]c增加只会暂时激活CSMDHs;缓慢或部分[Ca2+]c升高是无效的.
结论:
- 线粒体是专门调整以响应细胞质振荡的频率.
- [Ca2+]c振荡的频率,而不是持续水平,决定了CSMDHs和线粒体代谢的激活.
- 这种频率编码的信号提供了一个精确控制细胞能量生产的机制.
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