Aproteomic Analyusis Of The Apid Sitobion Avenae Under Heat Stress

In this study, the important wheat aphid Sitobion avenae were chosen as theresearch object to analyze the function of proteins under high temperature. Thedifferential expression of some proteins are obvious in abundance when Sitobionavenae induced by high temperature. The complex protein mixtures were separated bytwo-dimensional electrophoresis methods and the related spots of proteinssignificantly varying were selected and identified by mass spectrometry(MALDI-TOF/TOF) coupled with data bank investigations.In this study, Sitobion avenae experimental populations are established usingwheat raised by the sand culture method. This method is easy to operate,pollution-free, and aphids have high survival and reproduction speed. In addition, itcan guarantee an adequate supply of nutrition for wheat, so provides a large number ofhealth tested aphids, and the individual has the same physical standard. It provided thebasic guarantee for the subsequent series physiology and biochemistry researches ofSitobion avenae under laboratory conditions.Then, the saturated phenol extraction method was selected as the best proteinpreparation method, comparing to the TCA/acetone precipitation, PEG extraction anddirect cleavage method. This improved protein preparation method combined with thecharacteristics of aphid, minimizes the interference of all kinds of impurities. It has ahigh yield of 12.30 mg/g, and the protein sample is easily dissolved. Compared bytwo-dimensional electrophoresis, the saturated phenol extraction method has thehighest resolution, more than 800 protein spots distributed widely were detected oneach gel. Most importantly, it has the best reproducibility, so lay the foundation for thefurther comparative proteomic analysis of Sitobion avenae induced by hightemperature.38℃4h was established as the optimal high temperature induction model.Extracted proteins of the control materials and materials induced by high temperaturefor the two-dimensional electrophoresis, by the saturated phenol extraction method.Gel was analyzed by the ImageMaster? 2D Platinum 6.0 analysis software. Underhigh temperature stress, 29 differentially expressed protein spots with higher than 1.5-fold spot density were detected in gel image compared with control using silver staining. Protein spots were found to exhibit different dynamic patterns on 2-DE gels, which 17 protein spots were up-regulated expressed and 12 spots were down-regulated respectively. 18 proteins were identified by MALDI-TOF-TOF MS successfully, such as phosphoglycerate mutase, ubiquinone oxidoreductase, peptidylprolyl isomerase, muscle LIM protein, bicaudal, wd-repeat protein, twinstar, single-strand binding protein, OmpF-like porin, ubiquitin conjugating enzyme, eukaryotic translation initiation factor, etc., and there were two unknown protein either.These high temperature responsive proteins include enzymes involved with the basic metabolism, such as respiration and lipid metabolism, etc., cytoskeletal protein, and protein synthesis, folding and degradation-related proteins, etc. classified by the IAGC and INRA databases and related references. In addition, endosymbionts in aphid were found play a role in response to high temperatures.This study laids the foundation for subsequent analysis and authentication of protein function, provides a theoretical evidence for revealing heat-resistant mechanism of insect pests under global warming background, and further studies of prevention pest using high temperature.