iTRAQ串联质谱筛选尾吊小鼠感染空间诱变大肠杆菌后脾脏差异表达蛋白

目的应用同重同位素标记相对与绝对定量技术(iTRAQ),联合液相色谱串联质谱(LC-MS/MS),检测经空间诱变大肠杆菌(T1-13)感染尾吊模拟失重小鼠后,其脾脏组织中的差异蛋白,并探讨其生物学意义。方法 C57BL/6小鼠尾吊模拟失重后以空间诱变大肠杆菌灌胃建立感染模型,采用iTRAQ结合LC-MS/MS技术筛选脾脏组织差异表达蛋白,并对差异蛋白进行GO、pathway富集分析和STRING蛋白互作分析。结果共鉴定出2589个蛋白,尾吊组与对照组相比筛选出378个差异表达蛋白。尾吊染菌后与对照组相比,共筛选出452个差异表达蛋白,STRING蛋白互作网络中有286个差异蛋白间存在相互作用,这些差异蛋白经KEGG分析共得到32条存在显著性的通路,主要为氧化磷酸化通路,代谢通路、蛋白消化和吸收通路、蛋白酶体通路。结论成功筛选出了模拟失重后空间诱变大肠杆菌感染脾脏组织差异表达蛋白,这些差异蛋白可能通过调控代谢通路、不同环境下微生物代谢、颉氨酸/亮氨酸/异亮氨酸降解、溶酶体、碳代谢、吞噬体、丙酸代谢、蛋白酶体参与失重条件下免疫和炎症反应的发生。

iTRAQ Combined with LC-MS/MS to Be Applied to Screen Differentially Expressed Proteins in Spleen of Tail-suspension Mice Infected by Space Mutation E.coli

Objective To screen the differentially expressed proteins in the spleens of the mice after tail-suspension and infected by space mutation E.coli(T1-13),as well as to explore the biological significances.Methods The isobaric tags for relative and absolute quantitation (iTRAQ) combined with LC-MS/MS technique was used to detect the differentially expressed proteins in spleen of C57BL/6 mice after tail suspension and infected by space mutation E.coli (Tl-13).The screened differentially expressed proteins were analyzed with GO,pathway enrichment analysis and STRING protein interaction analysis.Results Totally,2589 proteins were identified and there were 378 differentially expressed proteins in tail suspension group compared with Con,452 differentially expressed proteins in tail suspension + T1-13 group compared with Con,in which there were 286 interacting proteins in STRING protein interaction network.KEGG results showed that there were 32 significant pathways enriched from these 286 interacting proteins,including oxidative phosphorylation,metabolic pathways,protein digestion and absorption,proteasome pathways.Conclusion The differentially expressed mice spleen proteins were successfully screened in simulated weightlessness combined with infection by space mutation E.coli,which may take part in the process of immunity and inflammation response in microgravity through the pathway regulation of metabolic,microbial metabolism in diverse environments,valine/leucine/isoleucine degradation,lysosome,carbon metabolism,phagosome,propanoate metabolism and proteasome.