在高导电性Ca2+激活的K+通道中的Ca2+门环的开放结构
Peng Yuan1, Manuel D Leonetti, Yichun Hsiung
1Laboratory of Molecular Neurobiology and Biophysics, Rockefeller University, Howard Hughes Medical Institute, 1230 York Avenue, New York, New York 10065, USA.
Nature
|December 6, 2011
概括
研究了对生理过程至关重要的高导电活性 (K+) 通道. 研究人员揭示了Ca2+结合的环结构,解释了结合如何打开这些重要的离子通道.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 离子通道生理学 离子通道生理学
背景情况:
- 高导电电压和Ca2+) 激活的K+通道连接了膜电压和细胞内Ca2+) 水平.
- 这些通道对神经元活动,肌肉收缩和感官调至关重要.
- 门环的无Ca2+) 结构已知,但与Ca2+) 结合的状态仍然难以捉摸.
研究的目的:
- 在高导电电压和Ca(2+) 激活的K+通道中确定封闭环的Ca(2+) 结合形状.
- 阐明这些通道中Ca2+) 激活的分子机制.
主要方法:
- 在X射线晶体学.
- 结构生物学是结构生物学.
- 生物化学测定 生物化学测定
主要成果:
- 确定了门环的Ca ((2+) 结合形状.
- 在Ca2+) 结合上观察到一个封闭环层的花状开放机制.
- 开口的程度与Ca2+能够打开通道孔的能力相关.
结论:
- 建立了K+通道的Ca(2+) 激活的分子基础.
- 这些发现表明,喘和高血压等疾病的门环中的潜在治疗点.
相关概念视频
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Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
01:24Non-gated Ion Channels
Ion channels are specialized proteins on the plasma membrane that allow charged ions to pass down their electrochemical gradient. Their main function is to maintain the membrane potential which is critical for cell viability. These channels are either gated or non-gated and can transport more than a thousand ions within milliseconds for the cellular event to occur.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
01:24Non-gated Ion Channels
Ion channels are specialized proteins on the plasma membrane that allow charged ions to pass down their electrochemical gradient. Their main function is to maintain the membrane potential which is critical for cell viability. These channels are either gated or non-gated and can transport more than a thousand ions within milliseconds for the cellular event to occur.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
01:19Ligand-gated Ion Channels
Ligand-gated ion channels are transmembrane proteins with a channel for ions to pass through and a binding site for a ligand. The channel opens only when a ligand attaches to the binding site.
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that include the...
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01:19Ligand-gated Ion Channels
Ligand-gated ion channels are transmembrane proteins with a channel for ions to pass through and a binding site for a ligand. The channel opens only when a ligand attaches to the binding site.
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that include the...
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01:16Calmodulin-dependent Signaling
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