REGULATION OF THE TRYTOPHAN GENES IN BACILLUS

芽孢杆菌中色氨酸基因的调控

• 批准号: 6526006
• 负责人: PAUL D GOLLNICK
• 金额: $ 28.34万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-15 至 2004-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6526006
• 关键词: Bacillus; RNA binding protein; bacterial RNA; bacterial genetics; genetic transcription; protein binding; tryptophan

Controlling transcription termination prior to the coding region is a commonly used strategy to regulate gene expression in bacteria, including many with importance to human health. Such control mechanisms are collectively termed attenuation and antitermination. The proposed research will investigate the mechanisms by which RNA binding proteins recognize and bind to specific sites in RNA, and how these interactions regulate transcription attenuation. The model system of study is the TRAP protein (trp RNA-binding Attenuation Protein), an RNA binding protein that regulates transcription attenuation of the tryptophan biosynthetic genes in Bacillus subtilis and related Bacilli. In the presence of excess tryptophan, TRAP is activated to bind to a series of 11 GAG or UAG repeats in the 5' leader region of the trp operon. This binding induces formation of a transcription terminator, which halts expression of the genes. TRAP is an 11 subunit protein that forms a symmetric ring. RNA binds to TRAP by wrapping around the outer perimeter of the protein ring. The detailed mechanism by which TRAP associates with its RNA target will be characterized using a combination of equilibrium binding studies, nucleoside analogs, and rapid-quench stopped-flow studies. TRAP is activated to bind RNA by binding 11 molecules of L-tryptophan. Crystallography, genetics and biochemical approaches will be used to determine the mechanism by which tryptophan binding activates TRAP. The third objective is to develop a more detailed understanding of the mechanism of TRAP mediated transcription attenuation. Key elements of the TRAP binding site in the trp leader will be altered and the effects of these changes on attenuation studied in vivo using a trpE''-'lacZ gene fusion. These studies will be guided by the information learned from in vitro studies of the TRAP/RNA interaction.

在编码区域之前控制转录终止是一个 通常使用的策略来调节细菌中基因表达，包括 许多对人类健康的重要性。这样的控制机制是统称的 被称为衰减和抗肿性。拟议的研究将调查 RNA结合蛋白识别并结合特定的机制 RNA中的位点，以及这些相互作用如何调节转录衰减。 研究模型系统是陷阱蛋白（TRP RNA结合衰减 蛋白质），一种调节转录衰减的RNA结合蛋白 枯草芽孢杆菌和相关杆菌中的色氨酸生物合成基因。在 陷阱过多的陷阱被激活与11系列结合 在TRP操纵子的5'领导区域中重复插科打或UAG。这种结合 诱导转录终结子的形成，该终结者停止了 基因。陷阱是形成对称环的11个亚基蛋白。 RNA与 通过缠绕在蛋白环的外周围缠绕陷阱。 捕集陷阱与其RNA目标相关的详细机制将是 使用核苷的平衡结合研究的组合表征 类似物和快速淬灭已停止了流量研究。陷阱被激活以结合RNA 通过结合11个l- tryptophan的分子。晶体学，遗传学和 生化方法将用于确定其机制 色氨酸结合激活陷阱。第三个目标是开发更多 详细了解陷阱介导的转录机理 衰减。 TRP领导者中陷阱绑定站点的关键要素将是 改变了这些变化对使用A在体内研究的衰减的影响 trpe'' - 'lacz基因融合。这些研究将以信息为指导 从陷阱/RNA相互作用的体外研究中学到的。