Bajer A S, Molè-Bajer J
Ann N Y Acad Sci. 1986;466:767-84. doi: 10.1111/j.1749-6632.1986.tb38458.x.
Mitosis is arrested in Haemanthus endosperm by amiprophos-methyl and oryzalin at a concentration of 100 nM, and anaphase chromosome movements are modified at 10 nM. Prolonged exposure to these drugs results in a classical c-mitosis. Anaphase chromosome movement is arrested within less than 30 seconds without any detectable change of MT arrangement, as shown by the immunogold staining method. In the next phase of amiprophos-methyl and oryzalin action, however, all non-kinetochore MTs, and especially those most sensitive to these drugs, polar microtubules, which form abundantly during anaphase, disassemble. Kinetochore microtubules form tight bundles that are very resistant to further drug action and often elongate before they finally disassemble. Because these drugs inhibit MT assembly in vitro in a concentration-dependent manner, we conclude that MT assembly is required for chromosome movements in anaphase and that the elongation of polar MTs is necessary for the progress of anaphase. No effect of the drugs on mitosis was detected, even at the saturated level, in the tissue culture of the frog Xenopus.
在海葱胚乳中，浓度为100 nM的甲基胺草磷和安磺灵可使有丝分裂停滞，而在10 nM时后期染色体运动受到影响。长时间暴露于这些药物会导致典型的c-有丝分裂。免疫金染色法显示，后期染色体运动在不到30秒内就会停滞，而微管排列没有任何可检测到的变化。然而，在甲基胺草磷和安磺灵作用的下一阶段，所有非动粒微管，尤其是那些对这些药物最敏感的、在后期大量形成的极微管，都会解体。动粒微管形成紧密的束状结构，对进一步的药物作用具有很强的抗性，并且在最终解体之前常常会延长。由于这些药物在体外以浓度依赖的方式抑制微管组装，我们得出结论，微管组装是后期染色体运动所必需的，极微管的延长是后期进程所必需的。即使在饱和水平下，在非洲爪蟾的组织培养中也未检测到这些药物对有丝分裂的影响。
