Three-dimensional localization and redistribution of F-actin in higher plant mitosis and cell plate formation.
Three-dimensional localization and redistribution of F-actin in higher plant mitosis and cell plate formation.
复制标题
F-肌动蛋白在高等植物有丝分裂和细胞板形成中的三维定位和重新分布。
DOI：
10.1002/cm.970100126
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发表时间：
1988
影响因子：
--
通讯作者：
Inoue,S
中科院分区：
文献类型：
--
作者：
Mole-Bajer,J;Bajer,AS;Inoue,S
用免疫金-银-增强法观察了高等植物Haemanthus胚乳细胞中F-肌动蛋白索的分布，并与同一细胞中免疫金染色微管的排列进行了比较。在有丝分裂和细胞板形成过程中，使用偏振光视频显微镜中的全载玻片的光学切片分析F‐actin电缆和微管的三维分布。F‐actin电缆在间期细胞质中形成松散的不规则网络。在有丝分裂过程中，这个网络的大部分保留在纺锤体的外部。在纺锤体内检测到一些F‐actin电缆。它们在有丝分裂过程中的显著重排似乎与微管阵列的存在和生长有关。在前中期，位于纺锤体表面的肌动蛋白索和存在于纺锤体内的肌动蛋白索倾向于平行于纺锤体的长轴排列。纺锤体外部的索不会重新定向，除了极区的索之外，它们似乎被拉长的纺锤体压缩。从中期后期开始，在赤道处积累了朝向不同方向的较短肌动蛋白索。它们中的一些被并入成膜体和细胞板中，并且随着细胞板的形成和老化而逐渐破碎。微管阵列附近的肌动蛋白电缆经常显示规则的点状染色模式。这种模式很少在外周细胞质中观察到，其中包含很少的微管。F‐actin电缆的重排模拟了纺锤体内含物的行为，如淀粉粒、线粒体等，这意味着F‐actin通过微管生长或微管相关的运输被动地重新分布。因此，基于肌动蛋白或肌动球蛋白的运动似乎不直接参与高等植物的有丝分裂和胞质分裂。
The distribution of F‐actin cables in dividing endosperm cells of a higher plant,Haemanthus, was visualized with the immunogold‐silver‐enhanced method and compared with the arrangement of immunogold‐stained microtubules in the same cells. The three‐dimensional distribution of F‐actin cables and microtubules during mitosis and cell plate formation was analyzed using ultrathin optical sectioning of whole mounts in polarized light video microscopy. F‐actin cables form a loose irregular network in the interphase cytoplasm. Much of this network remains outside of the spindle during mitosis. A few F‐actin cables were detected within the spindle. Their pronounced rearrangement during mitosis appears to be related to the presence and growth of microtubule arrays. During prometaphase, actin cables located on the spindle surface and those present within the spindle tend to arrange parallel to the long axis of the spindle. Cables outside the spindle do not reorient, except those at the polar region, where they appear to be compressed by the elongating spindle. Beginning with mid‐anaphase, shorter actin cables oriented in various directions accumulate at the equator. Some of them are incorporated into the phragmoplast and cell plate and are gradually fragmented as the cell plate is formed and ages. Actin cables adjacent to microtubule arrays often show a regular punctate staining pattern. Such a pattern is seldom observed in the peripheral cytoplasm, which contains few microtubules. The rearrangement of F‐actin cables mimicks the behavior of spindle inclusions, such as starch grains, mitochondria, etc., implying that F‐actin is redistributed passively by microtubule growth or microtubule‐related transport. Thus F‐actin or actomyosin‐based motility does not appear to be directly involved in mitosis and cytokinesis in higher plants.