The regulatory role of five small noncoding RNAs in Streptococcus pneumoniae

肺炎链球菌的CiaRH双组分调控系统与伯内酰胺耐药、裂解过程、遗传能力和毒力有关。Ciar调节子由24个基因组成，其中包括5个小的非编码RNA(CsRNAs)。对csRNA靶标的第一次搜索发现了三个基因。其中两个，Comc和Spr0081，在野生型菌株中被csRNAs下调，而第三个，Coma，只在一个高表达所有csRNAs的菌株中受到调控。在该菌株中，由于csRNA过量生产而抑制了com基因，从而阻止了遗传能力。此外，csRNAs与内酰胺类抗生素的抗性有关，但它们在这一过程中的分子靶标尚不清楚。在这里应用的项目中，将进一步详细探讨已建立的csRNA法规的表型后果。将分析单个csRNAs在调控过程中的作用，以及csRNAs中单个残基对靶标结合的贡献。为了寻找csRNAs的新靶点和相互作用伙伴，将进行生物信息学、蛋白质组分析和cDNA深度测序。新的调控相互作用将通过体内调控研究和体外csRNA结合试验进行评估。定义新的靶点和调控过程应该提供关于csRNA活动及其对肺炎链球菌生理影响的全面看法。

The two component regulatory system CiaRH of Streptococcus pneumoniae is implicated in ß-lactam resistance, lytic processes, genetic competence, and virulence. The CiaR regulon consists of 24 genes including five small non-coding RNAs (csRNAs). A first search for csRNA targets revealed three genes. Two of them, comC and spr0081, are downregulated by the csRNAs in the wild type strain, while the third, comA, is regulated only in a strain overexpressing all csRNAs. In this strain, genetic competence is blocked as a consequence of com gene repression by csRNA overproduction. In addition, csRNAs are implicated in ß-lactam resistance, but their molecular targets in this process are not yet known. In the project applied here, phenotypic consequences of the established csRNA regulations will be explored in further detail. The role of individual csRNAs in the regulatory process and the contribution of single residues in csRNAs to target binding will be analyzed. To find new targets and interaction partners of the csRNAs, bioinformatics, proteome analysis, and a cDNA deep sequencing approach will be pursued. New regulatory interactions will be evaluated by in vivo regulation studies and in vitro csRNA binding assays. Defining new targets and regulatory processes should provide a comprehensive view on csRNA activities and their impact on the physiology of S. pneumoniae.