Effects of Simulated Microgravity with Clinostat on Gene and Protein Expression in Escherichia coli

Zhang Yanling; Yang Hui; Xie Qiong; Qi Zhijun; Xue Xiaoping

Abstract：Objective To study the effects of simulated microgravity with clinostat on expression of gene and protein in Escherichia coli.Methods Escherichia coli ATCC 25922 strain was treated by clinostat for 2 weeks,16 target genes were selected,two-dimensional electrophoresis and mass spectrum were used to detect changes in protein expression and composition.RT-PCR was performed to detect different kinds of gene expressions in treated and untreated strains.Then total protein was extracted and used in two-dimensional electrophoresis analysis.Matrix assisted laser desorption/ionization - time of flight mass spectrometry (MALDI TOF/TOF MS) was used to analyze differential expression of protein between treated and untreated strains.Results With the treatment of simulated microgravity,four kinds of gene expressions were significantly up-regulated and five gene expressions were significantly down-regulated among 16 target genes; For 15 differential expression of protein,transcription antitermination factor NusG,redoxin and thiol peroxidase were up-regulated,hypothetical protein was down-regulated.Newly emerged proteins included glutamine ABC transporter periplasmic protein,and disappeared proteins were transcriptional regulator IclR family.Conclusion Simulated microgravity with clinostat(SMC) can induce variations in expression of gene and functional protein in Escherichia coli.