【摘要】 采用同源克隆和cDNA末端快速扩增技术(RACE)克隆了浙江枝吻纽虫热休克蛋白70(DzHSP70)基因全长cDNA序列,并利用荧光定量PCR方法,分析了该基因在重金属胁迫下的表达特征。结果表明,DzHSP70cDNA全长2827bp,包括294bp的5’UTR、628bp的3’UTR和编码634个氨基酸残基的1905bp的开放阅读框。HSP70家族的3个签名序列以及细胞质特异性调控基序EEVD等特征元件在DzHSP70中高度保守。重金属离子Fe3+、Pb2+和Cd2+均可上调该基因的表达,其中Pb2+的毒理效应最强。研究结果表明DzHSP70可能参与了机体对于重金属的解毒过程。更多还原

【Abstract】 With the approaches of homology cloning,RACE,the full-length HSP70 cDNA of Dendrorhynchus zhejiangensis was identified and characterized(denoted as DzHSP70) in the present study.Meanwhile,fluorescent real-time PCR was used to analyze varying degrees of induction of DzHSP70 mRNA expression in D.zhejiangensis exposed to heavy metals(Fe3+,Pb2+ and Cd2+).The results indicated the cDNA of DzHSP70 was of 2827bp,consisting of a 5’UTR of 294bp,a 3’UTR of 628bp,and a complete open reading frame of 1905bp encoding a polypeptide with 566 amino acid residues.The conserved motifs for HSP70 protein family including three signature sequences and a cytoplasm characteristic motif of EEVD were totally found in the deduced amino acid of DzHSP70.Three heavy metals Fe3+,Pb2+ and Cd2+ all could be induced the expression of DzHSP70 at mRNA level,where Pb2+ displayed more toxic effect on worm than those of Fe3+ and Cd2+.All our results indicated that DzHSP70 might be involved into mediating the process of heavy metals detoxification in worm.更多还原