Structural And Functional Insights Of Escherichia Coli SRNA GlmZ And The Interaction Between RNA Helicase CsdA And RNA

GlmZ is a small non-coding RNA (ncRNA) in E. coli. It is mainly involved in regulating the glmS mRNA expression, the total length of 207 nucleotides, and in the process of regulating the Hfq dependent on the chaperone proteins. When bacteria in preparing to split, the cells will synthesis a large number of biology membrane, the necessary conditions for synthesis of biofilm is a lot of glucosamine - 6 - phosphate(GlcN6P), and GlcN6P must be catalyzed by glucosamine - 6 - phosphate synthetase(GlmS). GlmS genes are activated, transcription glmS mRNA.After the e. coli in glmS mRNA transcription regulation is to manage through small RNA GlmZ.We use the method of SHAPE to study that how the small RNA GlmZ and RapZ protein interacte with each others and find the specific binding sites between them.The full name of SHAPE is Selective 2'- hydroxyl acylation analyzed by primer extension?In order to establish this method, we take the tRNA as experimental objects.From the SHAPE results can be concluded that the secondary structure of the tRNA is the classic model of the clover?Then we got RapZ protein crystals, and received the 2 sets diffraction datas that resolution within 3A, but because of the crystal accumulation problem, the structure cannot be solved. Besides, we use SHAPE analytic rox2 R2H1RNA secondary structure. Finally, I want to analysis the second structure of GlmZ by SHAPE and its binding site with RapZ, this part of the work has not been reasonable results.In addition, CsdA is a kind of DEAD - box RNA helicase in E.coli, it is a multi-domain protein of 629 amino acid residues.It participate in multiple cellular processes,such as RNA degradation, pre-mRNA splicing, translation initiation, the ribosome biosynthesis . CsdA is composed of two series of ReaA - like core domain, a dimer domain (DD) ,RNA binding domain (RBD), and C tail, CsdA need to be dimer to function, we have got the structure and function of every domain.CsdA core domain mainly the function of helicase and ATPase, we found that CsdA unwinding must to be dimer, but does not require two core domain.And by the enzyme activity and fluorescence polarization experiments found that CsdA RBD domain plays an important role in process of combination of RNA.