Alteration of microtubule dynamic instability during preprophase band formation revealed by yellow fluorescent protein-CLIP170 microtubule plus-end labeling
Alteration of microtubule dynamic instability during preprophase band formation revealed by yellow fluorescent protein-CLIP170 microtubule plus-end labeling
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DOI：
10.1105/tpc.008961
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发表时间：
2003-03-01
期刊：
影响因子：
11.6
通讯作者：
Gadella, TWJ
中科院分区：
文献类型：
--
作者：
Dhonukshe, P;Gadella, TWJ
在有丝分裂开始时，植物细胞形成一个微管状的前期带，确定细胞分裂的平面，但其形成的机制仍然是一个谜。在这里，我们描述了使用哺乳动物黄色荧光蛋白标记的CLIP170来可视化转染的豇豆原生质体和稳定转化和分裂的烟草亮黄2细胞中植物微管的动态+端。利用正端标记，我们观察了活植物细胞中不同微管构象的动态不稳定性。间期植物微管的生长速度为5 μ m/min，收缩速度为20 μ m/min，突变频率为0.02 μ m/ s，救援频率为0.08 μ m/ s，比哺乳动物的突变频率更快。值得注意的是，在前期带形成过程中，植物微管的生长速度和突变频率增加了一倍，而收缩速度和救援频率保持不变，使微管更短，更有活力。利用这些新的见解和四维延时成像数据，我们提出了一个模型，可以解释植物细胞中微管动态不稳定性的变化驱动微管在前期带和纺锤体形成过程中的戏剧性重排的机制。
At the onset of mitosis, plant cells form a microtubular preprophase band that defines the plane of cell division, but the mechanism of its formation remains a mystery. Here, we describe the use of mammalian yellow fluorescent protein-tagged CLIP170 to visualize the dynamic plus ends of plant microtubules in transfected cowpea protoplasts and in stably transformed and dividing tobacco Bright Yellow 2 cells. Using plus-end labeling, we observed dynamic instability in different microtubular conformations in live plant cells. The interphase plant microtubules grow at 5 mum/min, shrink at 20 mum/min, and display catastrophe and rescue frequencies of 0.02 and 0.08 events/s, respectively, exhibiting faster turnover than their mammalian counterparts, Strikingly, during preprophase band formation, the growth rate and catastrophe frequency of plant microtubules double, whereas the shrinkage rate and rescue frequency remain unchanged, making microtubules shorter and more dynamic. Using these novel insights and four-dimensional time-lapse imaging data, we propose a model that can explain the mechanism by which changes in microtubule dynamic instability drive the dramatic rearrangements of microtubules during preprophase band and spindle formation in plant cells.