考古细菌电压依赖的K+通道的功能分析
Vanessa Ruta1, Youxing Jiang, Alice Lee
1Howard Hughes Medical Institute, Laboratory of Molecular Neurobiology and Biophysics, Rockefeller University, 1230 York Avenue, New York, New York 10021, USA.
Nature
|March 12, 2003
概括
科学家在古生物中发现了电压依赖通道 (K(V),其功能与神经元中的功能相同. 这一发现表明这些重要离子通道的古代起源和保存结构.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 离子通道调节通过细胞膜的离子运输.
- 电压依赖的离子通道在响应膜电压变化时打开.
- 以前,电压依赖的K+,Ca2+和Na+通道被认为是真核生物特有的.
研究的目的:
- 从功能上描述一个高热友的古生物体的电压依赖 (K(V)) 通道.
- 研究电压依赖离子通道的进化起源和保存功能.
主要方法:
- 隔离和功能性特征的K ((V)) 通道从一个超热友的古生物.
- 电生理学研究以评估通道功能.
- 毒素结合测试以探测电压传感器结构的保存.
主要成果:
- 古代的K(V) 通道表现出与真核细胞神经元K(V) 通道相似的功能性质.
- 该通道的电压传感器显示结构性保护,由与 tarantula 毒素的高亲和度相互作用表明.
- 这表明,电压依赖的K(V) 通道并非单独存在于真核生物中.
结论:
- 电压依赖的K(V) 通道有很古老的起源,早于真核生物和古生物的分化.
- 功能和结构上的K(V) 通道的保存突显了它们在细胞生理学中的基本重要性.
- 这一发现挑战了以前对电压依赖离子通道进化轨迹的理解.
相关概念视频
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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...
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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...


