Differential Protein Analysis Of Alpha-Synaptic Nucleoprotein A53T Overexpressed Mouse Brain Tissue Based On DIA Quantitative Proteome Technique

Objective: To explore the proteomic changes in the brain tissue of human alpha-synuclein(α-Syn)A53T transgenic mice from the molecular level,providing a certain theoretical basis for the study of the pathogenesis of PD and the research and development of potential molecular targeting drugs.Methods: Human alpha-SYN A53T transgenic mice were divided into experimental group and control group.Twenty-four 12-month-old male alphasyn A53T mice were selected for the experimental group,and 20 12-month-old littermates male wild-type(WT)mice were selected for the control group.The behavioral changes of mice were detected by rotating rod test and open field test.Then,the protein expression difference between α-Syn A53 T transgenic mice and normal mice was compared by full scan Data Independent Acquisition(DIA)quantitative proteomics technique of high resolution mass spectrometry.Finally,GO functional enrichment analysis and KEGG pathway enrichment analysis were performed for these differentially expressed proteins.Finally,some of the different proteins were verified by Western blotting.Results: The results of the rotorod test showed that 12-month-oldα-Syn A53T transgenic mice performed better than wild-type control mice when compared with control mice.The results of open field test showed that the 12-month-old α-Syn A53T transgenic mice walked further and spent more time in the central area than the wild type mice.Pathological analysis showed that the expression of phosphorylatedα-Syn(Ser129),the main component of Lewy bodies(LBs),was significantly increased in α-Syn A53T transgenic mice at the age of 12 months.DIA proteomics mass spectrometry analysis showed that a total of 47 differentially expressed proteins were screened in the brain tissue ofα-Syn A53 T transgenic mice,of which 39 were up-regulated and 8 were down-regulated.GO functional enrichment analysis showed that these differentially expressed proteins were mainly involved in biological processes such as metabolism,endocytosis and calcium release.KEGG enrichment analysis showed that the differentially expressed proteins were mainly involved in biological pathways such as amino-trna biosynthesis,Rap1 signal transduction pathway,antigen processing and presentation.Bcl2 associated death promoter(BAD)protein was up-regulated in α-Syn A53T transgenic mice,suggesting that BAD may be an important factor leading to neuronal apoptosis in 12-month-old PD transgenic mice.Conclusion: 12 months old α-Syn A53T transgenic mice showed a trend of decreased anxiety like behavior and increased hyperactivity.The differentially expressed proteins screened by dia proteomics mass spectrometry are mainly involved in biological processes such as cell metabolism,ubiquitin regulation and rap signal transduction pathway,but the specific mechanism needs further verification and discussion.