The cloning, expression and preliminary function study of p53 in Plutella xylostella

• 1、School of Plant protection, Fujian Agriculture and Forestry University, Fuzhou 350002

Abstract：The p53 gene is the key gene to protect the stability of genome in multicellular organisms. The aim of present paper is to study the primary function of the p53 gene in diamondback moth with molecular biology methods, so as to reveal the control pathway of apoptosis in this model organism. The full-length of p53 is 2647 bp with a CDS of 1128 bp which is coding a protein of 375 aa. The Genbank accession number of Plutella xylostella p53 gene is KF991220. Based on this, the bioinformatic characterization such as conserved domain of protein and phylogenetic analysis, was performed. The prokaryotic expression of p53 showed that the P53 protein is about 40-44KD. And the eukaryotic expression of p53 gene in cultured cell line of Plutella xylostella showed that the overexpression of p53 can elevate the expression of its downstream target apoptotic genes such as reaper and gadd45, and can induce apoptosis slightly but not obviously. After the induction of apoptosis with botanical pesticides reagents, the expression of p53 is elevated to a certain extent in treatment of 2 hours, while reduced sharply after 6 hours and 12 hours of the treatments, when comparing with the control. The qRT-PCR results showed that p53 was expressed mainly in pupae and adult stage, merely in egg and last instar larvae. While the expression pattern of MDM2, the negative regulator of p53, seemed somehow opposite, expressing highly in egg, but lowly in adult and merely in pupae. Just like reported previously in numerous literatures, our computer model also showed that the P53 binding the MDM2 with the C-terminus. Totally, our project study the primary function of p53 gene in Plutella xylostella, based on the cloning and the relationship between p53 and its putative target genes.

Keywords： Apoptosis Plutella xylostella p53 prokaryotic expression eukaryotic expression