VISUALIZING ALLOSTERY IN THE GENE-REGULATORY LYSINE RIBOSWITCH

基因调节赖氨酸核糖开关中变构的可视化

• 批准号: 7954921
• 负责人: Nathan Baird
• 金额: $ 0.65万
• 依托单位: ILLINOIS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7954921
• 关键词: Anti-Bacterial Agents; Bacteria; Binding; Biophysics; Complement; Computer Retrieval of Information on Scientific Projects Database; Drug Delivery Systems; Eukaryota; Event; Flavin Mononucleotide; Funding; Gene Expression; Glycine; Goals; Grant; Homeostasis; Institution; Lysine; Modeling; Molecular Conformation; RNA; Regulator Genes; Reporting; Research; Research Personnel; Resources; Role; Shapes; Solutions; Source; Structure; Thiamine Pyrophosphate; United States National Institutes of Health; X-Ray Crystallography; aptamer; insight; interest; response

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Riboswitches are recently described RNA domains that directly bind to cellular metabolites and control gene expression in cis in bacteria and eukaryotes. Due to their role in cellular homeostasis and their potential as antibacterial drug targets, structural studies of riboswitches are of immediate interest. Crystal structures of several types of riboswitches bound to their cognate metabolites have been reported. However, the mechanism of riboswitch function is not well understood due to the lack of structural information regarding the metabolite-free conformation. The goal of this proposal is to probe the solution structure of the metabolite-free conformation and the metabolite-bound conformation of four riboswitches by SAXS: the thiamine pyrophosphate (TPP), flavin mononucleotide (FMN), glycine (Gly), and lysine (Lys) riboswitches. Previous studies of the glycine riboswitch have demonstrated the utility of SAXS studies (Lipfert et al, JMB, 2007) to investigate the global size and shape of these RNA aptamers. The conformational change induced upon binding metabolite is expected to be on the order of 5 - 20 Angstroms and is well suited for experimentation at the APS. Performing SAXS studies on both the metabolite-free and metabolite-bound conformations will provide insight into the global structural changes involved in the gene-regulatory response of riboswitches. Obtaining Rg and P(r) plots for these conformations will allow us to model the RNA before and after the gene-regulatory switching event. These studies will complement concurrent structure determination of the metabolite bound conformation by X-ray crystallography, providing a detailed structural explanation of riboswitch function.

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 核糖开关是最近被描述的RNA结构域，它直接与细胞代谢物结合，控制细菌和真核生物中顺式基因的表达。由于核糖开关在细胞内稳态中的作用和作为抗菌药物靶点的潜力，核糖开关的结构研究立即引起人们的兴趣。已报道了几种类型的核糖开关与其同源代谢物结合的晶体结构。然而，由于缺乏关于无代谢物构象的结构信息，核糖开关功能的机制还不是很清楚。 本研究的目的是用SAXS研究四种核糖开关的无代谢物构象和代谢物结合构象的溶液结构：硫胺素焦磷酸(TPP)、黄素单核苷酸(FMN)、甘氨酸(Gly)和赖氨酸(Lys)核糖开关。以前对甘氨酸核糖开关的研究已经证明了SAXS研究(Lipfert等人，JMB，2007)在调查这些RNA适配子的全球大小和形状方面的实用性。结合代谢物引起的构象变化预计在5-20埃量级，非常适合在APS进行实验。对代谢物自由构象和代谢物结合构象进行SAXS研究将有助于深入了解核糖开关基因调控反应所涉及的整体结构变化。获得这些构象的Rg和P(R)图将使我们能够对基因调控转换事件之前和之后的RNA进行建模。这些研究将补充用X射线结晶学同时测定代谢物结合构象的结构，为核糖开关功能提供详细的结构解释。