On the mechanism of anaphase A: evidence that ATP is needed for microtubule disassembly and not generation of polewards force.
On the mechanism of anaphase A: evidence that ATP is needed for microtubule disassembly and not generation of polewards force.
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关于后期A的机理：微管拆卸需要ATP而不是极力的产生ATP。
DOI：
10.1083/jcb.105.4.1691
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发表时间：
1987-10
影响因子：
7.8
通讯作者：
Pickett-Heaps, J D
中科院分区：
文献类型：
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作者：
Spurck, T P;Pickett-Heaps, J D
作为后期开始，有丝分裂PtK 1和蝾螈肺上皮细胞透化与毛地黄皂苷透化培养基（PM）。透化在约3分钟内停止细胞质活性、染色体运动和胞质分裂，推测是由于内源性ATP的损失。在PM中加入ATP、GTP或ATP-γ-S 4-7 min后，A后期重新开始，同时动粒纤维缩短。AMPPNP不能重新启动后期A;如果纺锤体在PM + DMSO中稳定，ATP无效。在PM +紫杉醇透化的细胞在其对ATP的反应不同，这取决于后期达到的阶段：一个中期后期细胞表现出初步的染色体运动回到中期板透化后，但后来，后期A恢复时，加入ATP。后期A也被冷PM（约16 ℃）或含有钙（1-10 mM）的PM重新激活。抗微管蛋白染色结果表明，微管在透化后相对稳定，并且微管在紫苑中的组装通常得到促进。星状和动粒MT对MT解体条件敏感，动粒MT的缩短总是伴随着后期A的再激活。间期和带间纺锤体MTs是相对稳定的冷和钙，直到提取的细胞被促进较长时间的PM，或更高浓度的洗涤剂。由于我们无法想象如何冷处理或相对较高的钙水平可以重新激活纺锤体运动在静止的，透性化的，大概是能量耗尽的细胞，我们得出结论，后期A是由能量储存在纺锤体。有效重新激活后期A的核苷三磷酸可能是动粒MT解体所必需的，没有它后期运动就无法进行。
As anaphase began, mitotic PtK1 and newt lung epithelial cells were permeabilized with digitonin in permeabilization medium (PM). Permeabilization stopped cytoplasmic activity, chromosome movement, and cytokinesis within about 3 min, presumably due to the loss of endogenous ATP. ATP, GTP, or ATP-gamma-S added in the PM 4-7 min later restarted anaphase A while kinetochore fibers shortened. AMPPNP could not restart anaphase A; ATP was ineffective if the spindle was stabilized in PM + DMSO. Cells permeabilized in PM + taxol varied in their response to ATP depending on the stage of anaphase reached: one mid-anaphase cell showed initial movement of chromosomes back to the metaphase plate upon permeabilization but later, anaphase A resumed when ATP was added. Anaphase A was also reactivated by cold PM (approximately 16 degrees C) or PM containing calcium (1-10 mM). Staining of fixed cells with antitubulin showed that microtubules (MTs) were relatively stable after permeabilization and MT assembly was usually promoted in asters. Astral and kinetochore MTs were sensitive to MT disassembly conditions, and shortening of kinetochore MTs always accompanied reactivation of anaphase A. Interphase and interzonal spindle MTs were relatively stable to cold and calcium until extraction of cells was promoted by longer periods in the PM, or by higher concentrations of detergent. Since we cannot envisage how both cold treatment or relatively high calcium levels can reactivate spindle motility in quiescent, permeabilized, and presumably energy-depleted cells, we conclude that anaphase A is powered by energy stored in the spindle. The nucleotide triphosphates effective in reactivating anaphase A could be necessary for the kinetochore MT disassembly without which anaphase movement cannot proceed.