Voltage-regulated sodium channel molecules.
Voltage-regulated sodium channel molecules.
复制标题
电压调节钠通道分子。
DOI：
10.1146/annurev.ph.46.030184.002505
复制
发表时间：
1984
影响因子：
18.2
通讯作者：
Agnew,WS
中科院分区：
文献类型：
--
作者：
Agnew,WS
总之，TTX 和 STX 结合已用于跟踪从电器官、哺乳动物骨骼肌和大脑中纯化钠通道蛋白。在每种情况下，它们都是比乙酰胆碱受体稍大的蛋白质，并表现出反映与膜脂密切相互作用的稳定性特性。主要肽成分似乎是大约 250,000 道尔顿的大糖肽。因为这显然是 electroplax 蛋白的唯一成分，所以它必须包含 TTX 受体位点，可能形成离子通路本身。 ScTX 的光标记和 Tityus γ 毒素 (58a) 的研究表明一个位点涉及门控过程，也与神经元和 electroplax 蛋白的大肽相关。较小的肽并不是所有制剂的一致特征，但可能有助于分子整体。然而，如果整个通道由单个极大的肽形成，则会产生有趣的机制含义，因为离子传输和电压传感机制将由折叠的多肽链内的结构域来解释。显然，将生化分离和重建与新的生物物理技术相结合的前景提供了令人兴奋的实验结合。
In summary, TTX and STX binding have been used to follow the purification of sodium channel proteins from electric organ, mammalian skeletal muscle, and brain. In each instance they were proteins somewhat larger than the acetylcholine receptor and exhibited stability properties that reflect an intimate interaction with membrane lipids. The principal peptide constituent seems to be a large glycopeptide of approximately 250,000 daltons. Because this is evidently the only constituent of the electroplax protein, it must contain the TTX receptor site, probably forming the ion pathway itself. Photo-labeling with ScTX and studies with Tityus gamma toxin (58a) indicate a site involved with gating processes, also associated with the large peptide of the neuronal and electroplax proteins. The smaller peptides are not consistent features of all of the preparations, but may contribute to the molecular ensemble. If, however, the entire channel were formed from a single extremely large peptide, there would be interesting mechanistic implications, because the ion transporting and voltage-sensing mechanisms would be accounted for by domains within the folded polypeptide chain. Clearly, the prospect for combining biochemical isolation and reconstitution with the new biophysical technology offers an exciting experimental conjunction.