Polarity of microtubules nucleated by centrosomes and chromosomes of Chinese hamster ovary cells in vitro.
Polarity of microtubules nucleated by centrosomes and chromosomes of Chinese hamster ovary cells in vitro.
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DOI：
10.1083/jcb.84.1.151
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发表时间：
1980-01
期刊：
影响因子：
--
通讯作者：
Borisy GG
中科院分区：
文献类型：
--
作者：
Bergen LG;Kuriyama R;Borisy GG
通过分析中心体微管和染色体微管以及鞭毛种子启动的微管的生长动力学，研究了这些微管的结构和生长极性。通过比较中心体和鞭毛播种的微管的伸长率，我们确定了中心体微管是只在正端自由生长，还是在负端自由生长，还是在两端自由生长。我们的结果表明，中心体微管的伸长速度仅与正端亚基的增加相对应。解聚速率也相当于只有正端的解聚速率。染色体微管的伸长类似于中心体启动的生长。由于数据不支持这些纺锤体微管的两端能够与溶液中的单体相互作用的假设，那么生长只能发生在组织中心的远端或近端，这意味着相对的一端不能用于亚基的交换。以鞭毛种子微管作为内对照的实验表明，负端的不活性不能用可扩散的抑制剂来解释，这暗示了结构上的解释。由于远端没有明显的封顶方式，而近端嵌入在着丝点周围的云层中，因此我们得出结论，中心体微管的方向是其正端位于成核部位的远端。对染色体微管的类似分析表明，它们的正端也必须定位在起始点的远端。
The structural and growth polarities of centrosomal and chromosomal microtubules were studied by analyzing the kinetics of growth of these microtubules and those initiated by flagellar seeds. By comparing rates of elongation of centrosomal and flagellar-seeded microtubules, we determined whether the centrosomal microtubules were free to grow at their plus ends only, minus ends ony, or at both ends. Our results show that centrosomal microtubules elongate at a rate corresponding to the addition of subunits at the plus end only. The depolymerization rate was also equivalent to that for the plus end only. Chromosomal microtubule elongation was similar to the centrosome-initiated growth. Since the data do not support the hypothesis that both ends of these spindle microtubules are able to interact with monomer in solution, then growth must occur only distal or only proximal to the organizing centers, implying tha the opposite ends in unavailable for exchange of subunits. Experiments with flagellar-seeded microtubules serving as internal controls indicated that the inactivity of the minus end could not be accounted for by a diffusible inhibitor, suggesting a structural explanation. Since there is no apparent way in which the distal ends may be capped, whereas the proximal ends are embedded in the pericentriolar cloud, we conclude that centrosomal microtubules are oriented with their plus ends distal to the site of nucleation. A similar analysis for chromosomal microtubules suggests that they too must be oriented with their plus ends distal to the site of initiation.
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影响因子：
5.6
作者：
ALLEN, C;BORISY, GG
通讯作者：
BORISY, GG
DOI：
10.1111/j.1749-6632.1975.tb19217.x
发表时间：
1975-01-01
影响因子：
5.2
作者：
MCINTOSH, JR;CANDE, Z;VANDERSLICE, K
通讯作者：
VANDERSLICE, K
DOI：
10.1111/j.1749-6632.1975.tb19196.x
发表时间：
1975-01-01
影响因子：
5.2
作者：
BORISY, GG;MARCUM, JM;JOHNSON, KA
通讯作者：
JOHNSON, KA
DOI：
10.1083/jcb.84.1.141
发表时间：
1980-01
期刊：
The Journal of cell biology
影响因子：
--
作者：
Bergen LG;Borisy GG
通讯作者：
Borisy GG
DOI：
10.1083/jcb.78.2.401
发表时间：
1978-08
期刊：
The Journal of cell biology
影响因子：
--
作者：
Hyams JS;Borisy GG
通讯作者：
Borisy GG