Heat-resistant variants of Chinese hamster fibroblasts altered in expression of heat shock protein.
Heat-resistant variants of Chinese hamster fibroblasts altered in expression of heat shock protein.
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DOI：
10.1073/pnas.82.23.8029
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发表时间：
1985-12
影响因子：
11.1
通讯作者：
A. Laszlo;G. Li
中科院分区：
文献类型：
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作者：
A. Laszlo;G. Li
中国仓鼠HA-1系的耐热变体在重复热处理后已被分离。耐热表型在70代以上一直保持稳定。70-kDa热休克蛋白家族的成员之一被发现在正常生长条件下在耐热变体中以更高水平合成。温和的热处理的变体线诱导的瞬时耐热性，伴随着额外的增加，在70 kDa的热休克蛋白的合成。总细胞RNA的无细胞翻译显示，对照细胞和加热的变体细胞中70-kDa热休克蛋白mRNA的含量更高。在变异细胞中合成的70-kDa热休克蛋白水平较高，可能是其信使mRNA水平改变的反映。此外，我们发现翻译控制在热休克HA-1细胞及其耐热变体中热休克蛋白的表达升高中起作用。耐热表型与70 kDa热休克蛋白水平增加的关联强烈表明，这种基因产物在保护细胞免受高温损伤方面发挥作用。
Heat-resistant variants of the Chinese hamster HA-1 line have been isolated after repeated heat treatments. The heat-resistant phenotype has been stable for over 70 passages. One of the members of the 70-kDa heat shock protein family was found to be synthesized at greater levels in the heat-resistant variants under normal growth conditions. Mild heat treatment of the variant lines induced a transient thermotolerance that was accompanied by additional increase in the synthesis of the 70-kDa heat shock proteins. Cell-free translation of total cellular RNA revealed greater amounts of 70-kDa heat shock protein mRNA in both control and heated variant cells. The greater levels of 70-kDa heat shock protein synthesized in the variant cells presumably are a reflection of altered levels of its messenger mRNA. In addition, we found that translational control plays a role in the elevated expression of heat shock proteins in heat-shocked HA-1 cells and their heat-resistant variants. The association of the heat-resistant phenotype with increased levels of a 70-kDa heat shock protein suggests strongly that this gene product plays a role in protecting cells from damage inflicted by elevated temperatures.