THE MECHANISM OF ACTION OF COLCHICINE

作者：Gary G. Borisy, Edwin W. Taylor · 发表于：The Journal of Cell Biology · 年份：1967 · DOI：10.1083/jcb.34.2.525 · 被引用次数：1058 · 研究领域：Bacteriophages and microbial interactions、Molecular Biology Techniques and Applications、Protist diversity and phylogeny

The majority of the colchicine-(3)H 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.