来自Cys-loop家族的阴离子和阴离子受体中的离子转位障碍
Ivaylo Ivanov1, Xiaolin Cheng, Steven M Sine
1Department of Chemistry and Biochemistry, University of California-San Diego, La Jolla, CA 92093-0365, USA. iivanov@mccammon.ucsd.edu
Journal of the American Chemical Society
|June 8, 2007
概括
在研究离子通道时,这项研究揭示了尼古丁酸乙胆受体 (nAChRs) 中的疏水性收缩阻碍了离子流. 相比之下,甘氨酸受体 (GlyRs) 保持水分,解释了它们不同的离子选择性和封闭机制.
科学领域:
- 生物物理学的生物物理.
- 结构生物学 结构生物学
- 计算神经科学是一种神经科学.
背景情况:
- 了解生物通道封闭和离子透是至关重要的.
- 结构生物学方面的进步为跨膜通道提供了分子洞察力.
研究的目的:
- 检查人类α7尼古丁乙胆受体 (nAChR) 和α1甘氨酸受体 (GlyR) 模型中的离子导电障碍和选择性起源.
- 研究孔隙结构和水分在受体功能中的作用.
主要方法:
- 分子动力学模拟以确定水密度概况.
- 适应性偏移力模拟用于重建平均力 (PMF) 的潜力.
- 基于鱼雷nAChR结构的建模.
主要成果:
- nAChR毛孔表现出疏水性收缩,形成离子转位障碍.
- 由于GlyR孔保持了良好的水分,对化物没有显著的疏水障碍.
- 静电学和通道入口/出口处的充电残留物解释了观察到的离子选择性.
结论:
- 疏水门是nAChR离子导电性的关键机制.
- GlyR的亲水孔促进了离子透,不同于nAChR.
- 总体而言,静电和充电残留物对于两种受体的选择性离子通道至关重要.
更多相关视频
相关概念视频
Multi-pass Transmembrane Proteins and β-barrels
In multi-pass transmembrane proteins, the polypeptide chain crosses the membrane more than once. The transmembrane polypeptide chain either forms an α-helix or β-strand structure. α-Helix containing multi-pass transmembrane proteins are ubiquitous, whereas β-strand containing ones are mainly found in gram-negative bacteria, mitochondria, and chloroplasts.
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
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...
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...
Pore Transport and Ion-Pair Transport
Pore transport and ion-pair formation are critical mechanisms for the absorption and distribution of drugs in the body.
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct microscopic...
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct microscopic...
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.


