Comparative Proteomics Analysis Of The Intoxication Response Of Culex Pipiens Quinquefasciatus Larval To Bacillus Thuringiensis Toxin

Over a million human beings died within one year because of suffering from the diseases spread by mosquitoes which turned to require for more actions on the governance against mosquitoes.Bti(Bacillus thuringiensis subsp.israelensis)a kind of common bio-pesticide which could do some certain damage to mosquitoes was far from being well spread since its high cost and low toxicity to mosquitoes.Now clear understanding of the mechanism how Bti worked to mosquitoes and the development of the high cost performance potion of Bti were urgently needed.In order to get a better understanding of the mechanism how Bti worked to Culex pipiens quinquefasciatus,the research on the proteomic level of Cx.quinquefasciatus was carried out in this study.Strain LLP29 is a kind of Bti isolated from Wuyi Mountain,which was proved to have high toxicity to mosquitoes.Crystal toxin was extracted from the fermented LLP29,and Cyt toxin,a part of crystal toxin,was isolated and purificated by Sephadex G-50 gel chromatography in the early stage of the research.Then the bioassay was done using crystal toxin and Cyt toxin against Cx.quinquefasciatus larval ?.The result showed Cyt toxin did not have significant toxicity to the culex larval,but the LC50 of crystal toxin was about 0.24 ?g/mL.A group of bioassay was continuously done with the LC50 concentration of crystal toxin followed with a control group.After 2DE of the midgut 33 differential protein spots were found including 22 up-regulating spots and 11 down-regulating spots.20 differential protein spots' detail information was getting by MS detection and Mascot data-comparation involved with a series of metabolisms such as ATP synthesis,alcohol transport,cytoskeleton fix,protein folding,cell detoxification,cell death,etc.,which pointed to a conclusion that the mechanism of how Bti worked to Cx.quinquefasciatus was a complex one containing pattern recognition,receptor interactions,signal transduction,regulation of gene expression and some other bio-processes.With this conclusion,we may form the theoretical basis for further study about finding and verificating key nodes genes in order to reveal the molecular mechanism of Cx's reaction against Bti toxin.