橡胶树热激蛋白HbHSP90.8-1基因的克隆与功能分析

Cloning and Functional Analysis of Heat Shock Protein Hb HSP90.8-1 from Hevea brasiliensis Müll.Arg.

白粉病是橡胶树生长发育过程中主要叶部病害之一。热激蛋白90(HSP90)分子伴侣在植物逆境胁迫抗性中起着重要作用。为研究HSP90家族成员结构及其在橡胶树抗白粉病中的功能,利用PCR技术从橡胶树品种热研73397叶片中克隆HbHSP90.8-1并采用生物信息学等技术对其结构和功能进行分析。结果表明,HbHSP90.8-1 cDNA序列全长2844 bp,开放阅读框(ORF)2454 bp,编码817个氨基酸。HbHSP90.8-1编码一个有信号肽、无跨膜结构且定位预测在内质网上的稳定亲水蛋白,存在HSP90 superfamily和HATPase superfamily结构域。系统进化分析结果表明橡胶树HbHSP90.8-1与木薯MeHSP90的亲缘关系最近,与麻风树JcHSP90聚为一类。通过qRT-PCR分析结果表明HbHSP90.8-1在橡胶树不同组织中均有表达,其在胶乳中的表达量最高;HbHSP90.8-1基因在白粉菌侵染、H2O2、ABA和ETH处理叶片中,表达量均呈现显著上调趋势;在MeJA和SA激素处理下,HbHSP90.8-1表达量呈现下调的趋势。说明HbHSP90.8-1参与橡胶树对白粉菌响应过程以及植物抗病相关激素信号转导途径。

Powdery mildew is one of the major leaf diseases in growth of rubber tree.Heat shock protein 90(HSP90)molecular chaperone plays an important role in plant stress resistance.To study the structure of the rubber tree HSP90 family members and their function in powdery mildew resistance,Hb HSP90.8-1 was cloned from rubber tree variety Reyan73397 leaf using PCR technology and its structure and function were analyzed by bioinformatics method.The results showed that the c DNA sequence of Hb HSP90.8-1 was 2844 bp in full length,2454 bp open reading frame(ORF)and encoded 817 amino acids.Hb HSP90.8-1 encoded a stable hydrophilic protein with signal peptide,no transmembrane structure and predicted positioning on endoplasmic reticulum,contained HSP90 superfamily and HATPase superfamily domains.Phylogenetic analysis showed that Hb HSP90.8-1 was closely related to Me HSP90,and classified into Jatropha Jc HSP90 and Castor Rc HSP90.The q RT-PCR analysis showed that Hb HSP90.8-1 was expressed in different tissues of rubber tree,and its expression level was the highest in latex.The expression of Hb HSP90.8-1 was significantly expressed and upregulated in leaves treated with Oidium heveae infection,H2O2,ABA and ETH respectively.However,under the treatment of Me JA and SA hormone,the expression of Hb HSP90.8-1 showed a downward trend.The study suggested that Hb HSP90.8-1 related to the powdery mildew resistance and the hormone signal transduction pathway related to plant disease resistance,and provided a technical guidance for the subsequent study on the molecular regulation mechanism of Hb HSP90.8-1 in the powdery mildew resistance in rubber tree.