通过可变酸化对Kv2.1通道的分级调节
Kang-Sik Park1, Durga P Mohapatra, Hiroaki Misonou
1Department of Pharmacology, School of Medicine, University of California, Davis, CA 95616, USA.
概括
神经元可塑性依赖于离子通道酸化. 氨酸去化Kv2.1通道,通过道激活的分级转移调节神经元刺激性和激发性质.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 离子通道生理学
背景情况:
- 神经元可塑性,大脑适应的能力,是由离子通道酸化动态调节的.
- Kv2.1通道在休息的哺乳动物神经元中显著酸化,影响其功能.
研究的目的:
- 调查Kv2.1通道酸化和尿素去酸化对调节神经元刺激性的作用.
- 为了确定Kv2.1上由氨素调节的特定酸化位点及其功能影响.
主要方法:
- 在细胞培养中利用质谱稳定同位素标记与氨基酸 (MS-SILAC) 来识别Kv2.1化位点.
- 采用位点定向突变发生 (阿拉宁和阿斯巴酸替代物) 来模仿或阻止氨酸介导脱化.
- 评估了这些突变对Kv2.1通道关口和神经元刺激性的功能后果.
主要成果:
- 确定了16个Kv2.1酸化位点,其中7个被发现被氨酸化.
- 单个位点对氨酸的突变诱导了道激活的增量转移,模仿了脱化.
- 多个位点的突变显示了附加效应,表明对Kv2.1通道功能的分级调节.
结论:
- 活动依赖的Kv2.1由氨酸的脱化会导致激活中的分级超极化转移,抑制神经元刺激性.
- 在许多部位的Kv2.1的可变酸化允许微调,活动依赖的调节神经元发射特性.
- 这种依赖酸化的机制提供了一种复杂的方式来控制神经元刺激性和可塑性.
相关概念视频
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Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
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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...
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Sodium ions make up approximately 90% of extracellular cations, with a normal blood plasma concentration of 136–148 mEq/L. A decrease in blood volume and pressure triggers the release of renin from granular cells in the juxtaglomerular complex (JGC), primarily in...


