STRUCTURAL STUDIES OF RIBOSWITCHES

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。 细菌中许多基因的表达可以由代谢产物分子控制，而不需要最初的蛋白质参与。然而，这种调控机制多年来一直不清楚。最近几个实验室发现，小分子代谢物直接与mRNAs的5个区域相互作用，调节RNA结构，影响靶基因的表达。这种新型的基因表达调控现在被描述为原核生物中的许多基因和真核生物中的一些基因，并与辅酶、核苷酸、氨基酸和糖的结合有关。代谢物敏感的RNA区域，称为核糖开关，由一个配体结合域和表达平台组成，其中包含参与基因表达的RNA元件。然后通过表达平台解释与代谢物结合相关的构象转变，从而在翻译或转录水平上进行调控。我们的研究重点放在自由和结合状态下代谢物感知模块的结构上，以更好地理解表达平台利用构象转变来进行基因表达的变构调控。

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. Expression of many genes in bacteria can be controlled by metabolite molecules without initial protein participation. However, mechanism of such regulation was not clear for many years. Recently several laboratories discovered that small metabolites directly interact with the 5 regions of mRNAs, modulate RNA structures and affect expression of the target genes. Such new type of gene expression control is now described for many genes in prokaryotes and some genes in eukaryotes and is associated with binding of coenzymes, nucleobases, aminoacids, and sugars. The metabolite-sensing RNA regions, termed riboswitches, are composed of a ligand-binding domain and expression platform that contains RNA elements involved in gene expression. The conformational transitions associated with metabolite binding are then interpreted through the expression platforms leading to regulation on the levels of either translation or transcription.Our research efforts are focused on the structures of the metabolite-sensing modules in the free and bound states, towards an improved understanding of the conformational transitions harnessed by the expression platforms for allosteric modulation of gene expression.