MOLECULAR MECHANISM OF OSMOTIC REGULATION IN PROKARYOTIC AND EUKARYOTIC MICROORGANISMS

原核和真核微生物渗透调节的分子机制

• 批准号: 08456048
• 负责人: MIZUNO Takeshi
• 金额: $ 4.8万
• 依托单位: NAGOYA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08456048/
• 关键词: OSMOTIC REGULATION; SIGNAL TRANSDUCTION; E.COLI; YEASTS.; GENE REGULATION.; OSMOSENSOR; TRANSCRIPTION FACTOR; 浸透圧センター; 原核生物; 真核生物; 分裂酵母

In general, protein phosphorylation is one of the most widely used mechanisms for regulating biological processes, including intracellular signal transduction. In eukaryotes, the cascades of protein phosphorylation and dephosphorylation events involving a number of protein tyrosine or serine/threonine kinases have been well studied. In contrast, recent intensive studies revealed that bacteria have devised a quite different phosphotransfer signaling mechanism for eliciting a variety of adaptive responses to their environment. Such a bacterial signal transduction mechanism was originally referred to as a "two-component regulatory system". The mode of molecular communication between a "sensor kinase" and its cognate phospho-accepting "response regulator" is principally based on histidine-to-aspartate (His-Asp) phosphotransfer. In Escherichia coli, for example, at least thirty different sensor-regulator pairs operate in a wide variety of adaptive responses. This particular signal transduction mechanism was once thought to be restricted to prokaryotes. However, many instances have recently been uncovered in diverse eukaryotic species. Furthermore, recent studies suggested that the molecular mechanism underlying the bacterial signal transduction is not simple as, and, in fact, is more sophisticated than thought previously. The new concept should be referred to as the "multi-step His-Asp phosphotransfer signaling mechanism". In this particular project, we extensively analyzed such signal transduction mechanisms both for prokaryotic and eukaryotic microorganisms, with special reference to their osmotic regulation.

一般来说，蛋白质磷酸化是调节生物过程（包括细胞内信号转导）最广泛使用的机制之一。在真核生物中，涉及许多蛋白质酪氨酸或丝氨酸/苏氨酸激酶的蛋白质磷酸化和去磷酸化事件的级联已经得到充分研究。相比之下，最近的深入研究表明，细菌设计了一种完全不同的磷酸转移信号机制，用于引发对其环境的各种适应性反应。这种细菌信号转导机制最初被称为“双组分调节系统”。 “传感器激酶”与其同源磷酸接受“反应调节器”之间的分子通讯模式主要基于组氨酸到天冬氨酸（His-Asp）的磷酸转移。例如，在大肠杆菌中，至少有三十对不同的传感器-调节器对以各种自适应响应方式运行。这种特殊的信号转导机制曾经被认为仅限于原核生物。然而，最近在不同的真核物种中发现了许多实例。此外，最近的研究表明，细菌信号转导背后的分子机制并不像以前想象的那么简单，事实上，比以前想象的更复杂。这个新概念应该被称为“多步His-Asp磷酸转移信号机制”。在这个特定的项目中，我们广泛分析了原核和真核微生物的信号转导机制，特别是它们的渗透调节。

项目成果

Kondo, H.et al: "Escherichia coli positive regulator OmpR hes a large loop structure at the putative RNA pelgmirase interaction site" Nature Struc.Biol.4. 28-31 (1997)

Kondo, H.等人：“大肠杆菌正调节因子 OmpR 在假定的 RNA pelgmirase 相互作用位点上是一个大环结构”Nature Struc.Biol.4。

Yaku, H., et al.: "Interaction between the CheY response regulator and the histidine containing phosphotransfer (HPt) domain of the ArcB sensory kinase in Escherichia coli." FEBS Lett.408. 337-340 (1997)

Yaku, H. 等人：“CheY 反应调节剂与大肠杆菌中 ArcB 感觉激酶的含有组氨酸的磷酸转移 (HPt) 结构域之间的相互作用。”

Nakashima,K.: "A novel menber of the cspA family of genes that is induced by cold shock in E-coli" J.Bacteriol.178. 2994-2997 (1996)

Nakashima,K.：“由大肠杆菌冷休克诱导的 cspA 基因家族的新成员”J.Bacteriol.178。

Nagoshima, K.et al: "Anovel menber of the cspA family of genes that is induced by cold shock in E.coli" J.Bacteriol. 178. 2994-2997 (1996)

Nagoshima，K.et al：“大肠杆菌冷休克诱导的 cspA 基因家族的新成员”J.Bacteriol。

Ueguchi, O.et al: "Methods in Enzymology" Academic Press, 1325 (1996)

Ueguchi, O.等人：“酶学方法”学术出版社，1325（1996）