快速化学诱导的变化PtdIns(4,5) P2门KCNQ离子通道的PtdIns(4,5) P2门KCNQ离子通道的快速化学诱导的变化
Byung-Chang Suh1, Takanari Inoue, Tobias Meyer
1Department of Physiology and Biophysics, University of Washington School of Medicine, Seattle, WA 98195, USA.
概括
酸丁酸4,5-双酸盐 (PI(4,5) P2) 耗尽完全抑制KCNQ离子通道电流,独立于其他信使. 这一发现澄清了信号通路,并突出了PI(4,5) P2
科学领域:
- 分子生物学分子生物学
- 细胞生理学 细胞生理学
- 生物化学 生物化学
背景情况:
- KCNQ离子通道对于神经元刺激能力至关重要.
- 脂酶C (PLC) 激活导致KCNQ电流抑制,但涉及的特定信使仍然存在争议.
- 酸,特别是酸4,5-双酸 (PI(4,5) P2),是膜蛋白的关键调节剂.
研究的目的:
- 为了最终确定负责PLC介导的KCNQ电流抑制的第二信使.
- 调查PI的直接作用{4,5) P2在调节KCNQ通道活动.
主要方法:
- 在化学暗示应用后,开发可转移酶以快速操纵血膜氏化物水平.
- 系统性耗尽和过度生产特定的酸,包括PI(4,5) P2和酸3,4,5-三酸盐 (PI(3,4,5) P3).
- 实时测量KCNQ离子通道电流,以应对类化物水平的变化,同时监测其他潜在的信使,如Ca2 +,二甲,和 1,4,5-三酸盐.
主要成果:
- 随着PI (4,5) P2的耗尽,KCNQ电流很快就被取消了,不管Ca2+,二甲醇或伊诺西1,4,5-三酸盐水平的变化如何.
- 过度生产PI(4,5) P2导致KCNQ当前增加了30%.
- 调节PI{3,4,5) P3水平并没有影响KCNQ电流.
结论:
- 耗尽PI{4,5) P2足以完全抑制KCNQ离子通道电流.
- 其他通常与PLC信号相关的第二信使不需要进行这种抑制.
- 开发的酶方法为研究酸介导信号网络提供了强大的工具.
相关概念视频
Mechanically-gated Ion Channels
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...
Mechanically-gated Ion Channels
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...
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.
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...
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...


