The mechanism of action of colchicine. Binding of colchincine-3H to cellular protein.
The mechanism of action of colchicine. Binding of colchincine-3H to cellular protein.
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DOI：
10.1083/jcb.34.2.525
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发表时间：
1967-08
影响因子：
7.8
通讯作者：
Taylor, E W
中科院分区：
文献类型：
--
作者：
Borisy, G G;Taylor, E W
与组织培养细胞（KB或Hela）结合的大部分秋水仙碱- 3h以非共价复合物的形式存在，均质后出现在可溶性部分的大分子中。类似的结合在体外被证明是局限于一个组分的可溶性部分。体内和体外的结合平衡常数和动力学常数基本相同。结合放射性被重新分离，并显示存在于与秋水仙碱具有相同色谱行为和特定抗有丝分裂活性的分子中。多种细胞和组织的体外结合活性测定显示与微管的存在相关。通过分裂细胞、有丝分裂器、纤毛、精子尾部和脑组织给予高结合活性。与黏菌提取物或纯化肌肉蛋白的结合非常低或无法检测到。结合位点的沉降常数为6S，表明该蛋白是微管的一个亚基。
The majority of the colchicine-3H bound by tissue culture cells (KB or Hela) was found to be present as a noncovalent complex with a macromolecule which appears in the soluble fraction after homogenization. Similar binding was demonstrated in vitro and was confined to a component of the soluble fraction. The binding-equilibrium constant and the kinetic constants were essentially the same in vivo and in vitro. Bound radioactivity was reisolated and shown to be present in a molecule with the same chromatographic behavior and specific antimitotic activity as colchicine. In vitro assay of binding activity of a variety of cells and tissues showed a correlation with the presence of microtubules. High binding activity was given by dividing cells, mitotic apparatus, cilia, sperm tails, and brain tissue. Binding to extracts of slime mold or to purified muscle proteins was very low or undetectable. The binding site had a sedimentation constant of 6S and it is suggested that the protein is a subunit of microtubules.