Analysis Of TCTP Related To Deltamethrin Stress And Resistance

Translationally controlled tumor protein(TCTP)is a highly conserved and expressed protein in the sequence,which is widely present in animals,plants and fungi.It has a great deal of biological functions,including the process of regulating the cell cycle and malignant metastasis,calcium binding protein,extracellular protein of histamine release,resistance to apoptosis,etc..Drosophila melanogaster is an important model organism commonly used in genetic research and widely used in biochemistry,molecular biology and developmental biology because of its clear genetic background and convenient experimental procedures.The previous study in our laboratory found that the Plutella xylostella of deltamethrin resistant strain TCTP expression level increased significantly compared with sensitive strain,but the relationship between TCTP and insecticide stress has not been reported.This study on TCTP with deltamethrin,parathion and carbaryl in the role of stress and its relationship with deltamethrin resistance has carried on the elementary exploration,the main results are as follows:1)Drosophila cells were treated with different concentrations of deltamethrin,parathion and carbaryl for 48 h.The expression of TCTP in cells was detected by real-time quantitative PCR.Under the treatment of different kinds of pesticides,TCTP gene expression levels were elevated in the cell,in which the most obvious impact of deltamethrin.Then select suitable concentration of deltamethrin,respectively to treated Drosophila Kc cell in 0 h,12 h,24 h,36 h,48 h,60 h.The results showed that the highest expression of TCTP in 24 h.2)To further verify the protective effect of TCTP on deltamethrin induced cell damage,we cloned the TCTP gene and transfected Drosophila cells.Real-time quantitative PCR and western blotting were used to detect transfection efficiency.Cytometry was used to determine the rate of apoptosis.The results showed that the rate of apoptosis in cells successfully overexpressed was significantly lower than in control cells,indicating a significant increase in resistance to deltamethrin.However,knocking down the expression of TCTP with dsRNA significantly increased the apoptosis rate of the cells,indicating that the resistance to deltamethrin was significantly decreased.3)The RNA was extracted from larvae of deltamethrin-resistant and deltamethrin-sensitive strains Plutella xylostella,and four different tissues of head,midgut,fat body and muscle.The expression of TCTP gene was detected by RT-PCR.The results showed that the total TCTP expression in the resistant strains was higher than that in the susceptible strains,and the TCTP gene expression levels in the head and fat bodies were significantly higher than those in the susceptible strains.TCTP presents constitutively high-level expression in resistant strain.The above results show that there is a certain correlation between the level of TCTP gene expression and resistance to insecticides,while the over-expression of TCTP exerts a protective effect on the deltamethrin stress of Drosophila cells.TCTP presents constitutively high-level expression in Plutella xylostella resistant strain.Therefore,we infer that TCTP may be a candidate gene associated with deltamethrin resistance,but the mechanism of TCTP in deltamethrin resistance still needs further study.