Molecular basis of thermosensing:: a two-component signal transduction thermometer in Bacillus subtilis
Molecular basis of thermosensing:: a two-component signal transduction thermometer in Bacillus subtilis
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DOI：
10.1093/emboj/20.7.1681
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发表时间：
2001-04-02
期刊：
影响因子：
11.4
通讯作者：
de Mendoza, D
中科院分区：
文献类型：
--
作者：
Aguilar, PS;Hernandez-Arriaga, AM;de Mendoza, D
原核生物和真核生物都对温度的降低做出反应，表达特定的蛋白质子集。虽然已经收集了大量关于冷休克诱导基因的信息，但关于温度调节的研究还没有明确确定在低温下负责热敏和信号转导的关键调节因子。在这里，我们确定了一个由传感激酶DesK和反应调节因子DesR组成的双组分信号转导系统，该系统负责枯草芽孢杆菌编码Delta 5-脂质去饱和酶的des基因的冷诱导。我们发现DesR结合到相对于温度调节des基因起始位点的-28至-77位延伸的DNA序列。我们进一步表明，不饱和脂肪酸（UFA），产品的Delta 5-去饱和酶，作为负信号分子的去转录。因此，由DesK-DesR双组分信号转导系统和UFAs组成的调节环提供了一种在低温下控制基因表达的新机制。
Both prokaryotes and eukaryotes respond to a decrease in temperature with the expression of a specific subset of proteins. Although a large body of information concerning cold shock-induced genes has been gathered, studies on temperature regulation have not clearly identified the key regulatory factor(s) responsible for thermosensing and signal transduction at low temperatures. Here we identified a two-component signal transduction system composed of a sensor kinase, DesK, and a response regulator, DesR, responsible for cold induction of the des gene coding for the Delta5-lipid desaturase from Bacillus subtilis, We found that DesR binds to a DNA sequence extending from position -28 to -77 relative to the start site of the temperature-regulated des gene. We show further that unsaturated fatty acids (UFAs), the products of the Delta5-desaturase, act as negative signalling molecules of des transcription. Thus, a regulatory loop composed of the DesK-DesR two-component signal transduction system and UFAs provides a novel mechanism for the control of gene expression at low temperatures.