细胞内门在Shaker K+通道中打开,由高亲和度金属桥梁定义
Sarah M Webster1, Donato Del Camino, John P Dekker
1Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature
|April 23, 2004
概括
电压通道控制神经元信号传递. 新发现揭示了Shaker通道结构,与细菌模型不同,可能解释其较低的离子导电率.
科学领域:
- 分子生物学分子生物学
- 神经科学是一个神经科学.
- 生物物理学的生物物理.
背景情况:
- 电压通道通过控制离子流来调节神经元的电信号.
- 沙克尔通道的关门机制对于神经元功能至关重要.
- 现有的模型建议在细菌通道中进行链运动以进行关.
研究的目的:
- 为了研究Shaker路的开放状态上的结构约束.
- 为了比较Shaker通道与细菌通道 (KcsA和MthK) 的封闭机制.
- 阐明Shaker和细菌通道之间的离子导电率差异的结构基础.
主要方法:
- 利用涉及囊的跨子单元金属桥梁来探测Shaker通道结构.
- 分析结构数据与细菌通道的现有晶体结构相结合.
- 在Shaker和细菌通道之间比较结构图案和封闭机制.
主要成果:
- 在开放状态的Shaker通道中,确定了两种类型的跨子单位金属桥梁.
- 这些桥梁限制了内孔螺旋体的结构和运动.
- 摇频道很可能在开放状态下保持KcsA类捆绑交叉图案,具有Pro-X-Pro曲.
结论:
- 摇通道的门机制与MthK提出的链运动模型有所不同.
- 在Shaker通道中保留的普罗林动图影响了内孔螺旋形状.
- 在Shaker通道中,一个更窄的束穿越可能解释了与细菌亲属相比,其离子导电率较低.
相关概念视频
Non-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.
Ligand-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...
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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Non-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.
Ligand-Gated Ion Channel Receptor: Gating Mechanism
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...
Ligand-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...
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...


