Molecular mechanism of the primary step of heat shock response

热激反应第一步的分子机制

• 批准号: 04454611
• 负责人: WADA Chieko
• 金额: $ 4.29万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04454611/
• 关键词: Heat shock Response; sigma^<32> stabilization; sigma^<32> translational regulation; Heat shock protein; σ^<32>; σ^<32>mRNA高次構造; 遺伝子発現; ストレス応答; 大腸菌; 熱ショック蛋白貭; 翻訳制御; メッセンジャーRNA; σ因子

The well-coordinated cellular response to the environmental stresses is essential for survival and maintenance of healthy life. Our understanding of the molecular regulatory mechanism of heat-shock response has been advanced by recent active investigations, among which studies with Escherichia coli has playd a role of providing basic and leading contributions. A heat-shock treatment triggers an increase of the cellular concentration of an RNA polymerase subunit sigma^<32>, which them induces expression(by transcription)of a group of genes coding for so-called heat-shock proteins such as the molecular chaperones GroE, DnaJ, DnaK, GrpE, and so on.Our recent ayalysis about the increase of the sigma^<32> concentration revealed that accmulation of abnormal proteins led the otherwise unstable sigma^<32> to become stable. It, however, did not increase the rate of sigma^<32> synthesis. Our results imply that there are at least two distinct pathways for the increase of sigma^<32> concentration. One is the stabilization pathway through accumulation of abnormal proteins, and the other is a pathway for stimulating sigma^<32> synthesis.For the latter pathway, we have shown the participation of the secondary structure mRNA transcribed from the rpoH gene encoding sigma^<32>. We suspect that there are in addition trans-acting factors ; thus we are engaged in finding them by devising a mutant-selection method.For the former pathway, we are analysing the domain structure of sigma^<32> by a site-directed-mutagenesis technique to determine the regulatory mechanism for the sigma^<32> stabilization.

对环境压力的良好协调的细胞反应对于生存和维持健康生活至关重要。最近的积极研究已经提出了我们对热震反应的分子调节机制的理解，其中对大肠杆菌的研究在这些研究中发挥了提供基本和领先的贡献的作用。 A heat-shock treatment triggers an increase of the cellular concentration of an RNA polymerase subunit sigma^<32>, which them induces expression(by transcription)of a group of genes coding for so-called heat-shock proteins such as the molecular chaperones GroE, DnaJ, DnaK, GrpE, and so on.Our recent ayalysis about the increase of the sigma^<32> concentration revealed that异常蛋白质的加速导致原本不稳定的Sigma^<32>变得稳定。但是，它并没有增加Sigma^<32>合成的速率。我们的结果表明，Sigma^<32>浓度的增加至少有两种不同的途径。一种是通过异常蛋白的积累的稳定途径，另一个是刺激Sigma^<32>合成的途径。对于后一种途径，我们显示了从编码Sigma^<32>的RPOH基因转录的二级结构mRNA的参与。我们怀疑还有一些跨性别因素。因此，我们通过设计一种突变体选择方法来寻找它们。对于以前的途径，我们通过位置定向的 - 刺激技术来分析Sigma^<32>的域结构，以确定Sigma^<32>稳定的调节机制。

项目成果

湯沢晴美、森浩禎: "バクテリアにおける熱ショック蛋白質の発現調節" 代謝. 29-8. 15-22 (1992)

Harumi Yuzawa、Hiroyoshi Mori：“细菌中热休克蛋白表达的调节”代谢 29-8。

Y.Kawasaki,C.Wada and T.Yura: "Binding of RepE initiator protein to mini-F DNA origin(ori2):Enhancing effects of repE mutations and DnaJ shock protein." J.Biol.Chem.267. 11520-11524 (1992)

Y.Kawasaki、C.Wada 和 T.Yura：“RepE 起始蛋白与 mini-F DNA 起点 (ori2) 的结合：增强 repE 突变和 DnaJ 休克蛋白的作用。”

H.Yuzawa,H.Nagai,H.Mori and T.Yura: "Heat induction of mediated by mRNA secndary structure:a primary step of the heat shock response in Escherichia coli." Nucleic Acids Res.21. 5449-5455 (1993)

H.Yuzawa、H.Nagai、H.Mori 和 T.Yura：“mRNA 二级结构介导的热诱导：大肠杆菌热休克反应的第一步。”

T.Yura, H.Nagaiand H.Mori: "Regulation of the heat-shock response in bacteria" Annu.Rev.Microbiol.47. 321-350 (1993)

T.Yura、H.Nagai 和 H.Mori：“细菌热休克反应的调节”Annu.Rev.Microbiol.47。

H.Yuzawa, H.Nagai, H.Mori and T.Yura: "Heat induction of mediated by mRNA secondary structure : a primary step of the heat shock response in Escherichia coli." Nucleic Acids Res.21. 5449-5455 (1993)

H.Yuzawa、H.Nagai、H.Mori 和 T.Yura：“mRNA 二级结构介导的热诱导：大肠杆菌热休克反应的第一步。”