橡胶树胶乳高表达热激蛋白HbHSP90.4基因抗逆功能分析

为了分析热激蛋白90（HSP90）基因在橡胶树（Hevea brasiliensis）逆境胁迫和激素转导中的作用，利用PCR技术从橡胶树品种热研73397胶乳中克隆得到HbHSP90.4基因全长cDNA序列，该基因含有1个2 451 bp开放阅读框（ORF），编码816个氨基酸。生物信息学分析结果表明，HbHSP90.4含有HSP90 superfamily和HATPase superfamily结构域，属于HSP90家族成员。系统进化分析发现该蛋白与木薯MeHSP90具有较近的亲缘关系。亚细胞定位预测显示HbHSP90.4基因定位在内质网。qRT-PCR结果表明HbHSP90.4基因主要在橡胶树胶乳中表达。干旱、冷胁迫、橡胶树白粉菌侵染、H₂O₂和MeJA处理均可促进胶乳HbHSP90.4基因上调表达，而其在ETH、SA和ABA处理中均呈现显著下调表达。构建植物表达载体HbHSP90.4-mScarlet，为进一步的转基因植物的做成准备了材料。本研究为阐明胶乳HbHSP90.4基因响应橡胶树逆境胁迫过程和植物激素信号传导途径分子调控机制奠定坚实基础。

Stress Tolerance Functional Analysis of the High Expression Heat Shock Protein HbHSP90.4 Gene from the Latex of Hevea brasiliensis

In order to analyze the role of Heat Shock Protein 90（HSP90） in stress and phytohormone signaling transduction in rubber tree， the full-length cDNA sequence of the HbHSP90.4 gene was cloned from rubber tree Reyan73397 latex by PCR， and HbHSP90.4 gene contained a 2 451 bp open reading frame（ORF） and encoded 816 amino acids. The results of bioinformatics analysis showed that HbHSP90.4 contained the HSP90 superfamily and HATPase superfamily domains， which was a member of the HSP90 family. Phylogenetic analysis revealed that this protein was closely related to cassava MeHSP90. Subcellular localization predictions showed that the HbHSP90.4 gene was localized in endoplasmic reticulum. The qRT-PCR results showed that the HbHSP90.4 gene was mainly expressed in rubber latex. Drought， cold， powdery mildew infection， H₂O₂ and MeJA treatments promoted the up-regulation of the HbHSP90.4 gene in latex respectively， while its expression was significantly down-regulated in ETH， SA and ABA treatments respectively. The plant expression vector HbHSP90.4-mScarlet was also constructed to prepare the material for further transgenic plants. This study laid a solid foundation for the elucidation of the molecular regulation of the latex HbHSP90.4 gene in response to rubber tree stress and the phytohormone signaling pathway.