Thyberg J, Moskalewski S
Department of Cell and Molecular Biology, Medical Nobel Institute, Karolinska Institutet, Stockholm, Sweden.
Cell Tissue Res. 1993 Sep;273(3):457-66. doi: 10.1007/BF00333700.
Double immunofluorescence microscopy was used to study the relationship between the Golgi complex and microtubules enriched in posttranslationally modified tubulins in cultured mouse L929 fibroblasts. In interphase cells, the elements of the Golgi complex were grouped around the microtubule-organizing center. From here, tyrosinated microtubules extended to the periphery of the cells, whereas the distribution of detyrosinated and acetylated microtubules largely overlapped with that of the Golgi complex. Treatment of cells with 10 microM nocodazole led to the disruption of all microtubules and dispersion of the Golgi elements. Following withdrawal of the drug, tyrosinated microtubules reformed first, followed by acetylated and then detyrosinated microtubules. In parallel, the Golgi elements moved back toward the juxtanuclear region and reestablished a close spatial relationship first with the acetylated and later also with the detyrosinated microtubules. Long-term recovery in the presence of 0.15 or 0.3 microM nocodazole allowed partial reformation of tyrosinated and acetylated microtubules, whereas no or only a few detyrosinated microtubules were detected. At the same time, the Golgi elements were grouped closer together around or on one side of the nucleus in close relation to acetylated microtubules. In synchronized cells released from a mitotic block, a radiating array of tyrosinated microtubules was first formed, followed by acetylated and detyrosinated microtubules. The Golgi elements initially came together in a few groups and thereafter took an overall morphology similar to that in interphase cells. During this reunification, they showed a close spatial relationship to acetylated microtubules, whereas detyrosinated microtubules appeared only later. Microtubules enriched in acetylated and/or detyrosinated tubulin thus appear to take part in establishing and maintaining the organization of the Golgi elements within an interconnected supraorganellar system. Whether the acetylation and detyrosination of tubulin are directly involved in this process or merely represent two modifications within this subpopulation of microtubules remains unknown.
采用双重免疫荧光显微镜技术研究培养的小鼠L929成纤维细胞中高尔基体复合体与富含翻译后修饰微管蛋白的微管之间的关系。在间期细胞中，高尔基体复合体的成分聚集在微管组织中心周围。从这里，酪氨酸化微管延伸到细胞周边，而脱酪氨酸化和乙酰化微管的分布在很大程度上与高尔基体复合体的分布重叠。用10微摩尔诺考达唑处理细胞导致所有微管破坏和高尔基体成分分散。药物撤除后，酪氨酸化微管首先重新形成，随后是乙酰化微管，然后是脱酪氨酸化微管。与此同时，高尔基体成分向近核区域移动，并首先与乙酰化微管，随后也与脱酪氨酸化微管重新建立紧密的空间关系。在0.15或0.3微摩尔诺考达唑存在下长期恢复允许酪氨酸化和乙酰化微管部分重新形成，而未检测到或仅检测到少数脱酪氨酸化微管。同时,高尔基体成分在细胞核周围或一侧更紧密地聚集在一起，与乙酰化微管密切相关。在从有丝分裂阻滞中释放的同步细胞中，首先形成放射状排列的酪氨酸化微管，随后是乙酰化和脱酪氨酸化微管。高尔基体成分最初聚集在一起形成几组，此后呈现出与间期细胞相似的整体形态。在这个重新聚集过程中，它们与乙酰化微管呈现出紧密的空间关系，而脱酪氨酸化微管仅在稍后出现。因此，富含乙酰化和/或脱酪氨酸化微管蛋白的微管似乎参与了在一个相互连接的超细胞器系统内建立和维持高尔基体成分的组织。微管蛋白的乙酰化和脱酪氨酸化是否直接参与这一过程，或者仅仅代表这一微管子群体内的两种修饰，仍然未知。
