Processing and degradation of regulatory RNAs in Escherichia coli

大肠杆菌中调节 RNA 的加工和降解

• 批准号: 39769073
• 负责人: Professorin Dr. Gabriele Klug
• 金额: --
• 依托单位: Institut für Mikrobiologie und Molekularbiologie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/39769073?language=en
• 关键词: Processing; degradation; regulatory; RNAs; Escherichia

To understand the regulation by RNA it is necessary to know how these RNA molecules are generated and turned-over. While some small RNAs represent primary transcripts, others are generated from larger RNA transcripts by processing. Some small RNAs exert their function by influencing the stability of the target RNA. Even if the small RNA does not influence the decay of target RNAs, its own turn-over rate may strongly influence its regulatory impact. While some small RNAs are very stable (half-life 30 min or more), others are turned-over within few minutes. Initially we will concentrate our studies on three systems: i) the ibpBA mRNA which harbours two putative RNA thermometers that are analyzed in regard to function by Franz Narberhaus, ii) rpoS and the small RNAs influencing rpoS expression involved in stationary phase and stress regulation (studied by R. Hengge and J. Vogel) and iii) the GcvB and Omr RNAs (affect outer membrane composition) which exhibit remarkably different half-lives. The decay of the RNAs will be analyzed under different growth conditions and in RNase mutant strains in order to get first insights into the underlying mechanisms. This will be complemented by in vitro studies using in vitro transcripts in combination with target RNAs and/or the RNA chaperone Hfq and isolated RNases or degradosome complexes. Hypotheses on the decay mechanisms arising from these studies will then be challenged by generating modified RNAs, whose decay will again be analyzed in vivo and in vitro.

为了理解RNA的调节，有必要知道这些RNA分子是如何产生和翻转的。虽然一些小RNA代表初级转录物，但其他RNA是由较大的RNA转录物通过加工产生的。一些小RNA通过影响靶RNA的稳定性来发挥其功能。即使小RNA不影响靶RNA的衰变，其自身的周转率也可能强烈影响其调节作用。虽然一些小RNA非常稳定（半衰期为30分钟或更长），但其他小RNA在几分钟内就会发生转变。最初，我们将集中我们的研究在三个系统：i）ibpBA mRNA，其中包含两个假定的RNA温度计，由Franz Narberhaus分析功能，ii）rpoS和影响rpoS表达的小RNA，涉及稳定期和应激调节（由R. Hengge和J. Vogel）和iii）GcvB和Omr RNA（影响外膜组成），它们表现出显著不同的半衰期。将在不同的生长条件下和在RNase突变株中分析RNA的衰变，以首次了解潜在的机制。这将通过使用体外转录物与靶RNA和/或RNA伴侣Hfq和分离的RNA酶或降解体复合物组合的体外研究来补充。从这些研究中产生的衰变机制的假设将受到挑战，产生修饰的RNA，其衰变将再次在体内和体外进行分析。