电压依赖的K+通道的X射线结构
Youxing Jiang1, Alice Lee, Jiayun Chen
1Howard Hughes Medical Institute, Laboratory of Molecular Neurobiology and Biophysics, Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, Rockefeller University, 1230 York Avenue, New York, New York 10021, USA.
Nature
|May 2, 2003
概括
我们从Aeropyrum pernix.确定了电压依赖的K+通道 (KvAP) 的结构. 电压传感器的柔性链表明它们移动以通过细胞膜导导离子.
科学领域:
- 结构生物学是结构生物学.
- 生物物理学的生物物理.
- 分子生物学分子生物学
背景情况:
- 电压依赖的K+通道对于神经和肌肉的电活动至关重要.
- 这些通道根据细胞膜电压变化调节离子导电.
- 了解它们的结构是阐明细胞电信号的关键.
研究的目的:
- 为了确定来自Aeropyrum pernix.的KvAP通道的高分辨率晶体结构.
- 描述KvAP中电压传感机制的结构特征.
- 提供对电压依赖性阴离子通道的封闭机制的见解.
主要方法:
- 采用X射线晶体学,以3.2A分辨率确定全长KvAP通道的结构.
- 隔离的电压传感器域被结晶并解析为1.9A.
- 单克隆Fab碎片被用来稳定和结晶通道复合体.
主要成果:
- KvAP通道结构显示了一个中央的离子导电孔,周围环绕着独特的"电压传感器".
- 这些是疏水,阴离,螺旋转螺旋结构,位于通道的外围.
- 确定了连接电压传感器到孔隙的灵活链,表明了运动的可能性.
结论:
- 确定的结构提供了电压依赖的K+通道的详细分子模型.
- "电压传感器"和灵活的链为电压依赖的门提供了一种新的机制.
- 这项研究推动了我们对离子通道功能和细胞电生理学的理解.
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.
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...
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...
G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
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.
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...
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...
Bewley Lattice Diagram
The Bewley lattice diagram, developed by L. V. Bewley, effectively organizes the reflections occurring during transmission-line transients. It visually represents how voltage waves propagate and reflect within a transmission line, making it easier to understand the complex interactions that occur.


