Webster D L, Watson K
Department of Biochemistry, Microbiology and Nutrition, University of New England, Armidale, NSW, Australia.
Yeast. 1993 Nov;9(11):1165-75. doi: 10.1002/yea.320091103.
The effects of heat shock and heat stress on the ultrastructure of Saccharomyces cerevisiae is reported. Following a mild heat shock, referred to as an increase in temperature from 25 degrees C to 37 degrees C for 30 min, we observed contraction of the nucleolus, formation of electron-dense particles (90 nm) in mitochondria and heat-shock granules (30-40 nm) in the cytoplasm. The electron-dense particles in the mitochondria were similar in appearance to those previously reported in plant cells exposed to elevated temperatures. In a heat-sensitive yeast strain, the nucleolus was severely aggregated after a mild heat shock, a treatment which hardly affected relatively more heat-resistant strains. The nucleolus was aggregated in all strains after a more severe heat stress (50 degrees C for 2 or 4 min). When cells were observed during a recovery period after heat stress it was found that nucleolar ultrastructure was regained more rapidly in cells that were previously heat shocked compared to cells that were stressed directly with no prior heat shock.
报道了热休克和热应激对酿酒酵母超微结构的影响。在轻度热休克后，即温度从25℃升高到37℃持续30分钟，我们观察到核仁收缩，线粒体中形成电子致密颗粒（90纳米）以及细胞质中形成热休克颗粒（30 - 40纳米）。线粒体中的电子致密颗粒在外观上与先前报道的暴露于高温下的植物细胞中的颗粒相似。在一个热敏感酵母菌株中，轻度热休克后核仁严重聚集，而这种处理对相对更耐热的菌株几乎没有影响。在更严重的热应激（50℃持续2或4分钟）后，所有菌株的核仁都发生了聚集。当在热应激后的恢复期观察细胞时，发现与未经预先热休克直接应激的细胞相比，先前受过热休克的细胞中核仁超微结构恢复得更快。
