Effects Of Electric Shock On Gene Expression Of Drosophila Melanogaster And Comparison With Different Stressors

As a kind of punitive stimulation,electric shock has a wide range of application scenarios in the research of various model organisms.For example,electric shock is an essential experimental condition in the behavioral research of stress,learning and memory of flies.However,the effects of electric shock on gene expression,physiology and biochemistry of Drosophila are still unclear.In this paper,the bioinformatics analysis of transcriptome sequencing data as the breakthrough point,through the personalized analysis of transcriptome data,combined with real-time fluorescence quantitative PCR experiments and other technologies,the shock stressors were deeply explored,and the data of different stressors were comprehensively analyzed to explore the similarities and differences of the effects of different stressors on Drosophila.This paper mainly studies the following three aspects1.Transcriptome data analysis.The sequencing data of Drosophila melanogaster treated with electric shock and non electric shock were used for quality control,data cleaning,and then transcriptome difference analysis.The results showed that there were21 up-regulated genes and 1829 down regulated genes in Drosophila within two hours after electric shock.Enrichment analysis showed that the differentially up-regulated genes were mainly enriched in the response to hyperoxia,the defense response to gram-positive and Gram-negative bacteria,the humoral immune response to antibiotics and microorganisms,and the defense response to bacteria,which indicated that electric shock might activate some genes of immune related pathways in Drosophila.GSEA analysis showed that Toll,Imd and JAK / STAT pathway were up-regulated,and toll pathway was more obvious.In the gene expression profile,it was further found that antimicrobial peptide gene,which is closely related to innate immunity of Drosophila melanogaster,increased significantly after electric shock.Interestingly,the expression of some epigenetic related genes showed significant changes,suggesting that the differential expression caused by electric shock may be related to the epigenetic modification of chromosomes.2.Regulation of antimicrobial peptide gene expression by electric shock.We first verified the previous laboratory findings: shock stress can induce the up regulation of antimicrobial peptide gene expression.Compared with the control group,the expression levels of metchnikowin(MTK)and diptericin(DPT)in male and virgin flies were significantly increased after electric shock treatment.Then,we explored the relationship between Toll signaling pathway and the expression of antimicrobial peptides induced by electric shock.The results showed that the induction of antimicrobial peptide gene expression by electric shock was related to the SPZ upstream of Toll pathway.Then,we found that the effect of electric shock on the expression of antimicrobial peptide gene can be transmitted through generations.The expression level of MTK gene in the offspring of virgin flies treated with electric shock was significantly higher than that of the control group.However,the high expression of antimicrobial peptides can not stabilize the cross generation inheritance.By the second generation,there was no difference between the shock group and the control group.In addition,the survival time of male flies treated with electric shock was significantly shorter under starvation or no food.Combined with sequencing analysis and literature research,we speculated that electric shock stress would cause metabolic disorder in Drosophila melanogaster,and the expression of antimicrobial peptides was a high energy consuming process,which led to the decrease of adaptability of Drosophila melanogaster to energy demand stress.3.Comparison of the effects of different stressors on gene expression of Drosophila melanogaster.By comparing the different gene data of Drosophila treated with different stressors,it was found that except antioxidant hydrogen sulfide,some antimicrobial peptide genes in Drosophila tended to be up-regulated under other stressors,and most antimicrobial peptide genes in Drosophila treated with electric shock,hyperoxia and aging were up-regulated.Subsequent enrichment analysis of the overlapping differential genes down regulated by electric shock,aging and ionizing radiation showed that these three conditions all affected the related pathways such as insemination,oviposition,negative regulation of protein hydrolysis and lipid metabolism.Based on the enrichment results of sequencing data,we can see that many metabolic pathways in Drosophila were significantly affected after electric shock,which may indicate that the metabolism of Drosophila was in trouble after electric shock.Some studies suggest that the high expression of antimicrobial peptide gene in Drosophila is a high energy consuming process;The function of lime gene is related to the increase of circulating carbohydrate level and the decrease of glycogen storage in Drosophila.This suggests that electric shock stress can cause metabolic disorder in Drosophila melanogaster,which leads to the decrease of adaptability to energy demand stress.This hypothesis is supported by the experimental data in this paper.The survival time of male flies treated with electric shock under starvation or drying conditions is significantly reduced.In general,the expression of most antimicrobial peptide genes in Drosophila is significantly up-regulated after electric shock,which is closely related to the upstream key gene SPZ of Toll pathway and can be passed on to the next generation.In addition,the survival time of male flies treated with electric shock was significantly shorter under starvation or no food,which implied that electric shock stress would cause metabolic disorder in Drosophila and reduce their adaptability to energy demand stress.Comparing the data of different stressors,we found that the effects of electric shock,aging and hyperoxia on Drosophila were similar,and the expression of some antimicrobial peptide genes were up-regulated;The effect of hydrogen sulfide on antimicrobial peptide gene of Drosophila was opposite.Electric shock,aging and ionizing radiation can affect the reproduction of Drosophila melanogaster,which also suggests that some of the effects of stress on Drosophila melanogaster will be transmitted to the offspring.