VISUALIZATION OF THE DYNAMIC INSTABILITY OF INDIVIDUAL MICROTUBULES BY DARK-FIELD MICROSCOPY
VISUALIZATION OF THE DYNAMIC INSTABILITY OF INDIVIDUAL MICROTUBULES BY DARK-FIELD MICROSCOPY
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DOI：
10.1038/321605a0
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发表时间：
1986-06-05
期刊：
影响因子：
64.8
通讯作者：
HOTANI, H
中科院分区：
文献类型：
--
作者：
HORIO, T;HOTANI, H
先前已经表明，两个群体的微管在体外以动态不稳定的方式共存：一个群体中的微管伸长，而另一个群体中的微管缩短并最终消失1，2。这一结论是基于微管溶液稀释后微管数量和长度分布的变化。在这里，我们直接表明，增长和缩短人口共存的稳态条件下，通过可视化的动态行为的个别microtubulesin vitroby暗视野显微镜。实时视频记录显示，微管的两端存在于生长或缩短阶段，并以随机方式在两个阶段之间频繁交替。此外，生长和缩短的末端可以共存于一个微管上，一端继续生长，另一端缩短。我们没有发现任何相关性的相位转换之间的个别微管或一个单一的微管两端之间。任何微管的两端都有明显不同的特征;活性端生长得更快，相位更频繁地交替，长度波动的程度比非活性端更大。微管相关蛋白（MAPs）抑制微管的相转换，稳定生长期的微管。
It has previously been shown that two populations of microtubules coexist in a dynamically unstable mannerin vitro: those in one population elongate while those in the other shorten and finally disappear1,2. This conclusion was based on changes in the number and length distribution of microtubules after dilution of the micro-tubule solution. Here, we demonstrate directly that growing and shortening populations coexist in steady-state conditions, by visualization of the dynamic behaviour of individual microtubulesin vitroby dark-field microscopy. Real-time video recording reveals that both ends of a microtubule exist in either the growing or the shortening phase and alternate quite frequently between the two phases in a stochastic manner. Moreover, growing and shortening ends can coexist on a single microtubule, one end continuing to grow simultaneously with shortening at the other end. We find no correlation in the phase conversion either among individual microtubules or between the two ends of a single microtubule. The two ends of any given microtubule have remarkably different characteristics; the active end grows faster, alternates in phase more frequently and fluctuates in length to a greater extent than the inactive end. Microtubule-associated proteins (MAPs) suppress the phase conversion and stabilize microtubules in the growing phase.