电压传感器域蛋白质是一种电压关闭的质子通道
Mari Sasaki1, Masahiro Takagi, Yasushi Okamura
1Section of Developmental Neurophysiology, Okazaki Institute for Integrative Bioscience, Higashiyama 5-1, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.
概括
研究人员确定了电压门式质子通道的第一个分子组成部分. 这一发现揭示了负责质子流动的四个跨膜蛋白质,这对于理解细胞过程至关重要.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 电子生理学 电子生理学
背景情况:
- 电压关闭的质子通道对于细胞功能至关重要,但缺乏分子识别.
- 以前的研究已经观察到这些通道,但无法确定它们的结构.
研究的目的:
- 为了识别电压门式质子通道的分子同一性.
- 描述已识别的蛋白质的功能性质.
主要方法:
- 在细胞中过度表达候选的四个跨膜蛋白质.
- 电生理学记录用于测量离子电流.
- 根据pH值和离子灵敏度的测试.
主要成果:
- 过度表达诱导了与质子流相一致的外向电流.
- 电流逆转潜力与质子平衡潜力相匹配.
- 蛋白质表现出pH取决于敏感性和敏感性,这是质子通道的特征.
结论:
- 一个四个跨膜蛋白质,类似于电压传感器领域,作为电压门的质子通道.
- 这种蛋白质本质上是一个通道,而不是一个调节器.
- 这一发现为电压受控质子通道活动提供了第一个分子基础.
相关概念视频
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.
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...
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...
G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
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...
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...


