Schumann Wolfgang
Institute of Genetics, University of Bayreuth, D-95440 Bayreuth, Germany.
Cell Stress Chaperones. 2003 Fall;8(3):207-17. doi: 10.1379/1466-1268(2003)008<0207:tbshss>2.0.co;2.
All organisms respond to a sudden increase in temperature by the so-called heat shock response. This response results in the induction of a subset of genes, designated heat shock genes coding for heat shock proteins, which allow the cell to cope with the stress regimen. Research carried out during the last 10 years with eubacteria has revealed that the heat shock genes of a given species fall into different classes (regulons), where each class is regulated by a different transcriptional regulator, which could be an alternative sigma factor, a transcriptional activator, or a transcriptional repressor. All regulons of a single species constitute the heat shock stimulon. In Bacillus subtilis, more than 200 genes representing over 7% of the transcriptionally active genes are induced at least 3-fold in response to a heat shock. This response becomes apparent within the first minute after exposure to heat stress, is transient, and is coordinated by at least 5 transcriptional regulator proteins, including 2 repressors, an alternate sigma-factor, and a 2-component signal transduction system. A detailed analysis of the regulation of all known heat shock genes has shown that they belong to at least 6 regulons that together comprise the B. subtilis heat shock stimulon. Potential thermosensors are discussed in this article.
所有生物体都会通过所谓的热休克反应来应对温度的突然升高。这种反应会导致一组特定基因的诱导表达，这些基因被称为热休克基因，编码热休克蛋白，使细胞能够应对压力状态。在过去10年中对真细菌进行的研究表明，特定物种的热休克基因可分为不同的类别（调控子），其中每个类别由不同的转录调节因子调控，该调节因子可以是替代西格玛因子、转录激活因子或转录抑制因子。单个物种的所有调控子构成热休克刺激子。在枯草芽孢杆菌中，超过200个基因（占转录活性基因的7%以上）在热休克反应中至少被诱导3倍。这种反应在暴露于热应激后的第一分钟内就会显现出来，是短暂的，并且由至少5种转录调节蛋白协调，包括2种抑制因子、1种替代西格玛因子和1个双组分信号转导系统。对所有已知热休克基因调控的详细分析表明，它们至少属于6个调控子，这些调控子共同构成了枯草芽孢杆菌热休克刺激子。本文讨论了潜在的热传感器。
