关键词: 朱砂叶螨, 热激蛋白, HSP70基因, 克隆, 表达, 温度胁迫, 实时定量PCR

Abstract:  In order to study the correlation between the expression of heat shock protein 70 (HSP70) and the adaptation to high and low temperature stress of Tetranychus cinnabarinus (Boisduval), the cDNA of a HSP70 gene named TCHSP70-4 was cloned by using the species homology and technique of rapid amplification of cDNA end (RACE) from carmine spider mite. The full-length of TCHSP70-4 cDNA (GenBank accession no.：EU977182) was 2 182 bp and the open reading frame (ORF) was 1 959 bp encoding a polypeptide of 653 amino acids, with an estimated molecular mass of 70.9 kDa and an estimated isoelectric piont (pI) of 5.40. It contained the highly conserved functional motifs of the HSP70 family. Comparative quantitative real-time RT-PCR was used to analyze the expression of TCHSP70-4 gene after the treatments of cold shock (4℃) and heat shock (40℃) for 1 h, respectively. The results showed that the mRNA expression of TCHSP70-4 was significantly down-regulated after cold shock and significantly up-regulated after heat shock. The result of TCHSP70-4 gene expression, on one hand, revealed that the gene is of induced HSP70 gene；on the other hand, it also revealed that its expression and protective effect were different after cold stress and heat stress.

Key words: Tetranychus cinnabarinus, heat shock protein, HSP70 gene, cloning, expression, temperature stress, real-time PCR