通过电压传感器领域的离子电流来自不同的蛋白质家族
César Arcos-Hernández1, Takuya Nishigaki2
1Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, 62210, Mexico. cesar.arcos@ibt.unam.mx.
Journal of biological physics
|October 18, 2023
概括
电压传感器域 (VSD) 可以产生离子电流,称为门孔电流,当关键带电残留物缺失或域被隔离时. 这些残留物的位置决定了蛋白质家族之间的电流电压依赖.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 细胞生理学 细胞生理学
背景情况:
- 膜电位 (Vm) 调节细胞功能.
- 电压传感器域 (VSDs) 赋予了对离子通道和传送器等跨膜蛋白的电压敏感性.
- VSD通常具有四个跨膜段 (S1-S4),在S4中具有负电荷的残留物,用于电压灵敏度.
研究的目的:
- 在具有VSD的蛋白质中审查和分类封闭孔流.
- 探索导致孔电流关闭的机制和条件.
- 为了加强解释这些电流的电压依赖性的模型.
主要方法:
- 关于含有VSDs的蛋白质的文献评论.
- 门孔电流分为病理,生理和人工类型的分类.
- 分析VSD结构和功能,特别是S4部分.
主要成果:
- 门孔电流在VSD中产生,在S4中缺乏保存的正电荷,或者当VSD被隔离时.
- 这些电流可以是病理的,生理的或人造的.
- S4段的位置,特别是没有正电荷的地方,决定了电流的电压依赖性.
结论:
- S4的位置,特别是没有正电荷,是封闭孔隙电流电压依赖的关键决定因素.
- 这一原则适用于含有VSDs的各种蛋白质家族.
- 了解孔电流对于各种生理和病理过程至关重要.
相关概念视频
Conservation of Protein Domains Over Different Proteins
10.9K
Protein domains are small structurally independent units that are part of a single amino acid chain. Although these domains are often structurally independent, they may rely on synergistic effects to perform their functions as part of a larger protein. Protein domains may be conserved within the same organism, as well as across different organisms.
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to...
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to...
10.9K
Voltage-gated Ion Channels
8.3K
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...
8.3K
Electrochemical Gradient and Channel Proteins: An Overview
2.3K
An electrochemical gradient is a fundamental concept in biology and chemistry. It regulates the movement of ions across cell membranes. This movement is influenced by two factors:
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to...
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to...
2.3K
Mechanically-gated Ion Channels
6.4K
Mechanically-gated ion channels are proteins found in eukaryotic and prokaryotic cell membranes that open in response to mechanical stress. Tension, compression, swelling, and shear stress can alter the conformation of the protein, opening a transmembrane channel that allows the passage of ions for signal transmission. In eukaryotes, mechanically-gated channels are distributed in several regions like the neurons, lungs, skin, bladder, and heart, where they play critical roles in numerous...
6.4K
Ion Channels
87.1K
The movement of ions like sodium, potassium, and calcium into and out of the cell is essential to maintain the electrochemical gradient in living cells. The ion channels—a class of membrane transport proteins—help maintain this ionic gradient for the smooth functioning of physiological activities such as maintaining cell size and volume, conducting nerve impulses, and gas and nutrient exchange.
Ion channels are specialized integral membrane proteins on the plasma membrane that allow...
Ion channels are specialized integral membrane proteins on the plasma membrane that allow...
87.1K
Non-gated Ion Channels
6.8K
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....
6.8K


