RIBOSOMES AS SENSORS OF HEAT AND COLD SHOCK IN ESCHERICHIA-COLI
RIBOSOMES AS SENSORS OF HEAT AND COLD SHOCK IN ESCHERICHIA-COLI
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DOI：
10.1073/pnas.87.15.5589
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发表时间：
1990-08-01
影响因子：
11.1
通讯作者：
NEIDHARDT, FC
中科院分区：
文献类型：
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作者：
VANBOGELEN, RA;NEIDHARDT, FC
几乎所有的细胞都通过诱导一组称为热休克蛋白（HSP）的蛋白质来对温度升高做出反应。由于大量的其他应激条件诱导HSP（或至少是最丰富的HSP），这种反应通常被称为普遍的应激反应。然而，对真正模拟温度变化的条件的仔细研究表明，这些蛋白质是响应细胞翻译能力的变化而诱导的。为了直接测试这一点，大肠杆菌细胞用靶向原核核糖体的抗生素处理。使用二维凝胶来评估这些药物改变热休克蛋白合成速率的能力。一组抗生素诱导热休克蛋白，而第二组抑制热休克蛋白并诱导另一组通常在冷休克反应中诱导的蛋白。根据所用的浓度，热休克蛋白或冷休克蛋白的诱导模拟了轻度或重度的温度变化。此外，发现冷休克诱导组的抗生素阻断热休克蛋白的高温诱导。这些结果表明，核糖体作为原核生物的热休克和冷休克反应网络的传感器，在真核生物中也可能发挥作用。
Nearly all cells respond to an increase in temperature by inducing a set of proteins, called heat shock proteins (HSPs). Because a large number of other stress conditions induce the HSPs (or at least the most abundant ones), this response is often termed the universal stress response. However, a careful study of conditions that truly mimic a temperature shift suggested that these proteins are induced in response to a change in the translational capacity of the cell. To test this directly, Escherichia coli cells were treated with antibiotics that target the prokaryotic ribosome. Two-dimensional gels were used to evaluate the ability of these drugs to alter the rate of synthesis of the HSPs. One group of antibiotics induced the HSPs, whereas a second group repressed the HSPs and induced another set of proteins normally induced in response to a cold shock. Depending on the concentration used, the induction of the heat or cold shock proteins mimicked a mild or severe temperature shift. In addition, antibiotics of the cold shock-inducing group were found to block high temperature induction of the HSPs. The results implicate the ribosome as a prokaryotic sensor for the heat and cold shock response networks, a role it may serve in eukaryotes as well.