黑姆可以结合并抑制哺乳动物依赖的Slo1 BK通道
Xiang Dong Tang1, Rong Xu, Mark F Reynolds
1Department of Physiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Nature
|October 3, 2003
概括
血红素对蛋白质至关重要,直接调节大导电量依赖的Slo1 BK通道. 这种结合抑制电流,揭示了血红素作为急性信号分子的新角色.
科学领域:
- 生物化学 生物化学
- 神经科学是一个神经科学.
- 分子生物学分子生物学
背景情况:
- 血红素是血红蛋白中的重要辅因子,对氧化还原反应至关重要.
- 在生物生成过程中,血红素被酶性地纳入阿波-血红蛋白.
- 大导电性依赖的Slo1 BK通道具有保留的血红素结合基因.
研究的目的:
- 研究和Slo1 BK通道之间的直接相互作用.
- 阐明血红素结合对BK通道活动的功能后果.
主要方法:
- 克隆人类SLO1和老鼠大脑野生型BK通道的电生理记录.
- 对血红管相互作用的结构证据分析.
主要成果:
- 血红素直接与人类的Slo1 (hSlo1) 通道蛋白结合,在氧化和还原状态.
- 血结合极大地抑制了跨膜K+电流.
- 抑制通过降低通道开通频率而发生.
结论:
- 血质直接调节Slo1 BK通道.
- 这种相互作用揭示了血红素作为急性信号分子的新功能.
- 乙基道是血液中介调节的直接目标.
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