Modulation of the Golgi apparatus in Saccharomyces cerevisiae sec7 mutants as seen by three‐dimensional electron microscopy
Modulation of the Golgi apparatus in Saccharomyces cerevisiae sec7 mutants as seen by three‐dimensional electron microscopy
复制标题
三维电子显微镜观察到酿酒酵母 sec7 突变体中高尔基体的调节
DOI：
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
F. Képès
中科院分区：
文献类型：
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作者：
A. Rambourg;Y. Clermont;F. Képès
使用电子显微镜在酿酒酵母厚高尔基切片中检查了高尔基体的三维结构，该切片由野生型菌株和 sec7 突变体制备，在 37°C 的非允许温度下维持不同时间，然后返回到 24°C 的允许温度。戊二醛固定标本的锇后固定量减少，高尔基体元素的含量强烈染色，从而有利于其三维表征。在野生型酿酒酵母中，高尔基体元件通常表现为分散在整个细胞质中的膜小管的孤立网络。沿着这样的网络，充满染色物质的膨胀物与附近的分泌颗粒的大小相似，表明后者是由高尔基体元件的碎片形成的。在 sec7 突变体中，在低（0.1%）葡萄糖培养基中维持 37°C，分泌颗粒的数量逐渐减少并很快消失。与此同时，高尔基小管网络的大小和复杂性增加，失去了扩张，然后转化为扁平的球囊，形成多达七个或八个球囊的堆叠，类似于哺乳动物细胞中看到的高尔基体堆叠。然而，与后者相反，球囊之间的连接是明显的，并且高尔基体相关的小囊泡通常不存在。回到允许的温度（24°C）后，分泌颗粒重新出现，高尔基体堆叠的尺寸逐渐减小，并恢复其分离的小管状网络的初始状态。因此，在 sec7 突变体中，在 37°C 低葡萄糖培养基中生长，分泌颗粒的分离被阻断。结果，高尔基体膜积累形成堆叠且互连的球囊的连续系统。 © 1993 Wiley-Liss, Inc.
The three‐dimensional configuration of the Golgi apparatus has been examined with the electron microscope in thick Golgi sections of Saccharomyces cerevisiae prepared from a wild‐type strain and from sec7 mutants maintained for various periods of time at the nonpermissive temperature of 37°C and then returned to the permissive temperature of 24°C. Reduced osmium postfixation of glutaraldehyde fixed specimens stained intensely the content of Golgi elements and thus facilitated their three‐dimensional characterization. In wild‐type S. cerevisiae, the Golgi elements usually appeared as isolated networks of membranous tubules dispersed throughout the cytoplasm. Along such networks, distensions filled with stained material were similar in size to nearby secretory granules, suggesting that the latter formed by fragmentation of the Golgi elements. In sec7 mutants maintained at 37°C in low (0.1%) glucose medium, secretion granules progressively decreased in number and soon disappeared. Concomitantly the networks of Golgi tubules increased in size and complexity, lost their distensions, and then transformed into flattened sacules forming stacks of up to seven or eight saccules that were similar to the Golgi stacks seen in mammalian cells. However in contrast to the latter, connections between the saccules were evident and Golgi‐associated small vesicles were generally absent. Following return to the permissive temperature (24°C), secretion granules reappeared, the Golgi stacks progressively decreased in size, and resumed their initial state of separated small tubular networks. Thus in sec7 mutant, grown at 37°C in low glucose medium, segregation of secretory granules is blocked. As a result, Golgi membranes accumulate to form a continuous system of stacked and interconnected saccules. © 1993 Wiley‐Liss, Inc.
DOI：
10.1016/s0021-9258(18)37842-6
发表时间：
1988-08
期刊：
The Journal of biological chemistry
影响因子：
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作者：
Tilman Achstetterg;Alex Franzusoffi;Charles Field;Randy W. Schekman
通讯作者：
Tilman Achstetterg;Alex Franzusoffi;Charles Field;Randy W. Schekman