Effects Of Chitin Deacetylase Gene (Serpentine And Vermiform) On The Drosophila Wing Development

Drosophila is one of the important model organism,its development process is relatively clear,and Drosophila is the ideal model of study of gene function during the process of the development,it can also be used for the screening of new pesticide target genes to provide theoretical support.Most insects are agricultural pests,causing great economic losses to agricultural production.Chitin is the unique composition of insect epidermis,digestive tract and various tissues.Various enzymes are involved in the synthesis and degradation of chitin,and chitin deacetylase(CDAs)plays an important role in the modification and assembly of chitin.The CDAs gene promotes the acetylation of N-acetylglucosamine,which is linked to the?-1,4 glycosides in chitin,to varying degrees of deacetylchitin(chitosan).Because Humans and other higher animals don't have chitin metabolic systems,chitin deacetylase can be a target gene for developing environmentally friendly insecticides with great market potential.In this study,we put the Drosophila serpentine(serp)and vermiform(verm)gene as the research objects.Firstly,by using Gal4/UAS system,the genes were silenced in different tissues of the Drosophila,and then observed the development of Drosophila,so as to explore the role of the gene in different tissues of Drosophila.Secondly,this study selected Drosophila wings as further research objects,and explored the autonomy and function of the gene in the Drosophila wing.This paper mainly studies from the following three aspects:1.Effects of serpentine and vermiform gene on Drosophila development.We supressed the expression of serpentine(serp)and vermiform(verm)gene on the different Drosophila body,such asepidermis,trachea,corpus allatum,nerves,eyes and wings by using the Drosophila Gal4/UAS system,and then observed the offsprings phenotypes.The results showed that the serp and verm gene play different role in different tissue during Drosophila development.2.The autonomy study of serpentine and vermiform gene in the development of Drosophila wings.Previous studies have found that the Drosophila didn't die and the wings were deformed after supression of serp and verm gene on the wings.Because previous studies have shown that the serp was secretion by fat body,therefore in this article,we used the Gal4/UAS system specific knockdown the serp or verm gene in the Drosophila wings and fat body to analysis the sources of the two genes in wings.After repress serp and verm gene in fat body,we use RT-qPCR to examine the efficiency of silence of fat body and detect the expression of serp and verm genes on the wings,it was found that the expression of serp and verm genes in Drosophila wings are not reduced.It demonstrated that the serp and verm gene in Drosophila wings are synthesis by wing cells,and they are not transferred by the fat body.3.The role of serpentine and vermiform genes in Drosophila wing development.Previous studies about the function of serp and verm genes in Drosophila tracheal development indicated that the two genes had similar structure and function.However,our previous studies found that the adult wings showed different phenotypes after repressing the serp and verm genes in Drosophila under the three different Gal4 drivers.Subsequently,repression serp and verm genes in different wing areas under the control of the different Gal4 drivers,the defects of the wings was also found to be different.Then using the temperature control factor Gal80~tss to regulate the degree of repression of serp and verm genes on different development stage,we found that both genes resulted in more significant effects after the gene was suppressed at longer time.Previous studies found the serp and verm gene modificated the chitin to chitosan.therefore,in this paper,we observed the changes of deacelation degree of the adult wings after downregulated the serp and verm gene expression in Drosophila different wing area by using chitosan staining.After repress the verm gene,we found that the deacelation degree of chitin are not changed.But after repression the serp gene the deacelation degree of chitin are strongly reduced.We use AFM to detection the wing membrane's micro structure,observed the wing membrane on the surface of the nanoscale structure“lotus leaf”after repress the serp and verm genes,found that the wing membrane's bump are changed and it look not same,the influence of the serp gene are more strongly.Using the projection electron microscope to observe vein chitin lamella structure found that repress the serp gene does not affect the chitin and layer structure,but the layer structure are disappeared after repress the verm gene,verm gene is more important to vein chitin form the lamella structure.The results showed that serp and verm genes are really play different roles in the development of Drosophila wings.