一个通道突变物消除了与无活化粒子结合的快速无活化
Yichen Liu1, Francisco Bezanilla2,3
1Department of Neurobiology, University of Chicago, Chicago, IL, USA.
The Journal of general physiology
|November 27, 2024
概括
电压门道的快速无活化是一个多步骤的过程. 一个特定的突变破坏了这个过程,揭示了另一个频道状态,影响了电压传感器.
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:
- 电压通道的快速失活对于神经冲动控制至关重要.
- 正规的球链模型可能无法完全解释失活.
- 新出现的证据表明,在快速无活化过程中,存在多种形状变化.
研究的目的:
- 调查IFM动机和毛孔域相互作用在快速通道失活中的作用.
- 在毛孔领域描述特定双重突变 (CW) 的功能后果.
主要方法:
- 使用了离子电流,门电流和光测量的组合.
- 采用了电生理学技术来研究通道功能.
- 在孔域底部研究了一种双重突变 (CW).
主要成果:
- 双重突变CW通过破坏IFM动机和孔隙之间的通信来取消快速无活化.
- 在CW突变体中,IFM动机结合导致了另一个开放状态,而不是无活化.
- 这种替代的开放状态显著改变了电压传感器的运动.
结论:
- 哺乳动物电压门道的快速无活化是一个多步骤的过程.
- 该CW突变深刻地改变了通道行为,而不仅仅是删除快速停用.
- 这项研究揭示了一种新的替代开放状态,影响电压传感器动态.
相关概念视频
Voltage-gated Ion Channels
8.0K
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...
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...
8.0K
Ligand-Gated Ion Channel Receptor: Gating Mechanism
2.1K
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...
2.1K
The Role of Ion Channels in Neuronal Computation
3.1K
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential....
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential....
3.1K
Ligand-gated Ion Channels
12.2K
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...
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...
12.2K
The Resting Membrane Potential
130.4K
Overview
130.4K
Resting Membrane Potential
18.0K
The relative difference in electrical charge, or voltage, between the inside and the outside of a cell membrane, is called the membrane potential. It is generated by differences in permeability of the membrane to various ions and the concentrations of these ions across the membrane.
The Inside of a Neuron is More Negative
The membrane potential of a cell can be measured by inserting a microelectrode into a cell and comparing the charge to a reference electrode in the extracellular fluid. The...
The Inside of a Neuron is More Negative
The membrane potential of a cell can be measured by inserting a microelectrode into a cell and comparing the charge to a reference electrode in the extracellular fluid. The...
18.0K


