热激蛋白90基因(heat shock protein 90genes,hsp90s)是与生物发育、生物防御反应以及生物抗环境胁迫等相关的多功能基因。本试验以RT-PCR结合RACE方法从腐烂茎线虫Ditylenchus destructor中克隆出1个hsp90,命名为Dd-hsp90-1,基因登录号为HQ901595。Dd-hsp90-1cDNA全长序列含有1个2 160bp的开放性阅读框(ORF),编码719个氨基酸残基,其5′末端和3′末端分别含有70bp和117bp的非编码区(UTR)。Dd-hsp90-1内含子外显子结构分析结果表明,其基因组序列包含9个内含子,且各内含子两端剪接位点序列遵守GT/AG规则。Dd-hsp90-1基因的推定蛋白Dd-HSP90-1分子质量约为82.79ku。该基因为单拷贝基因,并且与其他热激蛋白90基因高度同源。Dd-HSP90-1具有热激蛋白90家族保守的序列和基系。此外,该基因还具有胞质型热激蛋白90的5个特征序列和特异MEEVD基系,这表明Dd-hsp90-1为胞质型热激蛋白90。系统进化分析结果显示,Dd-hsp90-1与松材线虫热激蛋白90基因(GenBank登录号ACY01918)亲缘关系最近,氨基酸序列一致性达到86.65%。同时,热激蛋白90基因的系统进化分析结果也体现了植物寄生线虫之间的取食行为差异。
Heat shock protein 90 genes(hsp90s) are multifunctional genes,which are related to biological development,biological defense reactions,environmental stress tolerance and so on.In this research,a heat shock protein 90 gene(Dd-hsp90-1;GenBank Accession: HQ901595) was cloned from Ditylenchus destructor by RT-PCR and RACE.The cDNA sequence consisted of a 2 160 bp open reading frame(ORF) encoding 719 amino acid residues that was franked by a 70 bp 5′-untranslated region(UTR) and a 117 bp 3′-UTR.The result of intron-exon structure analysis showed that the genomic sequence of Dd-hsp90-1 also contained 9 introns.And all the introns obeyed the GT/AG rule in the splice-site junctions.The molecular weight of Dd-hsp90-1 deduced protein was about 82.79 ku.Dd-hsp90-1 was a single copy gene was highly homologous to other hsp90s.There were consensus amino acid sequences and motifs of HSP90s in the amino acid sequence of deduced protein Dd-HSP90-1.Furthermore,the deduced protein Dd-HSP90-1 also contained five signature sequences and MEEVD motif specific to cytoplasmic HSP90s.All of these demonstrated that Dd-hsp90-1 was an cytoplasmic hsp90.Phylogenetic dendrogram indicated that Dd-hsp90-1 was most closely related to Baursaphelenchus xylophilus hsp90(ACY01918) with 86.65% sequence identity.It also revealed the differences in the feeding behaviors of plant parasitic nematodes.