核糖开关调控抗生素抗药性基因的研究

项目名称： 核糖开关调控抗生素抗药性基因的研究

项目编号： No.31330022

项目类型： 重点项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： Alastair Murchie

作者单位： 复旦大学

项目金额： 304万元

中文摘要： 抗生素耐药性日益巨增，已发展成世界范围内的一大公共健康威胁，因此，抗生素耐药性产生机制的研究至关重要。核糖开关是存在于mRNA非编码区域的RNA序列，通过与小分子配体结合改变自身结构从而调控基因表达。申请人以通讯作者身份于2013年1月在CELL杂志上（复旦为第一单位）首次报道了氨基糖苷类抗生素耐药性核糖开关，该核糖开关通过结合氨基糖苷类抗生素引起结构改变从而调控下游抗药性基因的表达。本项目将利用已有的实验体系重点研究除氨基糖苷类以外的其他几大类抗生素的耐药性产生机制，利用体内报告基因系统，体外RNA和抗生素相互作用检测技术以及RNA化学修饰和突变等生化方法寻找调控这几大类抗生素耐药性基因的新型核糖开关。本项目是已发表工作的延伸和拓展，将从一个全新角度深入阐明耐药性产生的分子机理，开创耐药性机理研究的新领域，引领和占据世界耐药性研究的学科前沿，为人类最终认识并战胜致病菌耐药性提供理论基础。

中文关键词： 抗生素耐药性;核糖开关;RNA二级结构;基因表达调控;

英文摘要： Antibiotic resistance has increasingly become one of the biggest problems in the world. Riboswitches are regulatory RNAs that bind small molecule metabolites and cofactors; they exploit specific interactions between low molecular weight metabolites and non-coding regions of messenger RNAs to regulate the biosynthetic pathway of the metabolite. They utilize a simple feedback mechanism whereby the interplay between two distinct structures in the mRNA controls the level of gene expression, in response to cellular conditions. As corresponding author, the applicant has published a paper titled “Riboswitch Control of Aminoglycoside Antibiotic Resistance” in CELL January, 2013. The paper reported the discovery of a new aminoglycoside binding riboswitch that is widely distributed amongst antibiotic resistant bacterial pathogens. This riboswitch is present in the leader RNA of the resistance genes that encode the aminoglycoside acetyl transferase (AAC) and aminoglycoside adenyl transferase (AAD) enzymes that confer resistance to aminoglycoside antibiotics through modification of the drugs. We show that expression of the AAC and AAD resistance genes is regulated by aminoglycoside binding to a secondary structure in their 5’ leader RNA. Reporter gene expression, direct measurements of drug RNA binding, chemical probing and UV cross-linking combined with mutational analysis demonstrate that the leader RNA functions as an aminoglycoside sensing riboswitch in which drug binding to the leader RNA leads to the induction of aminoglycosides antibiotic resistance. Based on this work, we will continue to search for new riboswitches that control other class of antibiotic resistance. This study will shed light on the understanding and mechanism of the antibiotic resistance and pave foundation for solving the problem of antibiotic resistance.

英文关键词： antibiotic resistance;riboswitch;RNA secondary structure;regulation of gene expression