Transcriptional profiling to elucidate processes regulated by 2',3'-cyclic nucleotide phosphodiesterase (CNPase) in Salmonella Typhimurium 14028s (Salmonella) II.

The impact of 2',3'-cyclic nucleotide phosphodiesterase (CNPase) on global gene expression in Salmonella was investigated by heterologous expression of mammalian CNPase in a strain containing a deletion of the 'rna' gene. 'rna' encodes an endoribonuclease capable of hydrolyzing RNA into 2',3'-cyclic nucleotide monophosphates (2',3'-cNMPs) such that deletion of 'rna' drastically reduces 2',3'-cNMPs presence to undetectable levels. Expression of CNPase in this strain allowed any effects of CNPase unrelated to 2',3'-cNMPs to be observed. Overall design: Global transcript levels in a 'rna' deletion strain of Salmonella expressing CNPase were compared to levels in control cells with the same deletion expressing a catalytically inactive variant of CNPase in order to identify cellular processes modulated by CNPase that are unrelated to 2',3'-cyclic nucleotide monophosphates.

本研究通过在带有"rna"基因缺失的沙门氏菌菌株中异源表达哺乳动物来源的2',3'-环核苷酸磷酸二酯酶（2',3'-cyclic nucleotide phosphodiesterase, CNPase），探究了该酶对沙门氏菌全基因组基因表达的影响。"rna"基因编码一种可将RNA水解为2',3'-环核苷酸单磷酸（2',3'-cNMPs）的核糖核酸内切酶，因此"rna"基因的缺失可使2',3'-cNMPs的含量大幅降低至无法检测的水平。在该缺失菌株中表达CNPase，即可观测到CNPase不依赖于2',3'-cNMPs的各类生物学效应。实验总体设计：为了鉴定CNPase所调控的、不依赖于2',3'-环核苷酸单磷酸的细胞生物学过程，本研究将表达CNPase的沙门氏菌"rna"基因缺失菌株的全局转录本水平，与携带相同基因缺失、仅表达催化失活型CNPase的对照菌株的转录本水平进行了对比。