取决于电压的酸化可能会在克罗马芬细胞中招募Ca2+电流促进
C R Artalejo1, S Rossie, R L Perlman
1Department of Pharmacological and Physiological Sciences, University of Chicago, Illinois 60637.
Nature
|July 2, 1992
概括
牛的克罗马芬细胞表现出两种Ca2+电流. 电压依赖酸化调节了促进Ca2+电流的招募,这是理解离子通道调节的关键发现.
科学领域:
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
- 离子通道生理学 离子通道生理学
背景情况:
- 牛素细胞具有明显的全细胞Ca2+电流:标准和促进成分.
- 促进Ca2+电流通常是静止的,但可以通过特定的去极化模式来激活.
- 蛋白激酶A的激活表明酸化在Ca2+电流促进中的作用.
研究的目的:
- 研究蛋白质酸化在招募促进Ca2+电流中的作用.
- 阐明这些电流的电压依赖性招募背后的机制.
主要方法:
- 使用的牛染色细胞.
- 应用了预脉冲和重复脱极化来研究Ca2+电流招募.
- 研究了蛋白质酸化抑制剂和酸酶2A注射的作用.
- 在不同的条件下检查了招聘的可逆性.
主要成果:
- 脱极化诱导的促进Ca2+电流的招募是一个快速的,第一阶段的过程.
- 蛋白质酸化和酸酶2A抑制招募的抑制剂.
- 电压依赖性招募,通常是可逆的,成为不可逆的与酸酶抑制剂.
结论:
- 电压依赖的Ca2+通道或相关蛋白质的酸化介导了促进Ca2+电流的招募.
- 这种酸化机制允许膜潜能调节离子通道活性.
相关概念视频
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Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
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Voltage-gated Ion Channels
Voltage-gated ion channels are transmembrane proteins that open and close in response to changes in the membrane potential. They are present on the membranes of all electrically excitable cells such as neurons, heart, and muscle cells.
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
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