巴西橡胶树中小檗碱桥酶HbBBE1在逆境胁迫中的作用（英文）  

Multiple Roles of Berberine Bridge Enzyme Gene HbBBE1 in Response to Stress in Hevea brasiliensis Muell. Arg.

作　　者：王萌 张冬 陆燕茜 肖化兴 郑服丛 张宇 WANG Meng;ZHNG Dong;LU Yan-Xi;XIAO Hua-Xing;ZHENG Fu-Cong;ZHANG Yu(Institute of Tropical Agriculture and Forestry,Hainan University,Haikou 57022)

机构地区：[1]海南大学热带农林学院,海口570228

出　　处：《植物研究》2018年第5期704-713,共10页Bulletin of Botanical Research

基　　金：the Earmarked Fund for Modern Agro-industry Technology Research System(CARS-33-BC1);National Natural Science Foundation of China(31660204,31660187);Doctoral research foundation of Hainan University(KYQD(ZR)1733)

摘　　要：小檗碱桥酶(BBE,EC1. 5. 3. 9)是小檗碱生物合成中的关键酶。通过PCR扩增,克隆了橡胶树中HbBBE1基因。HbBBE1的启动子区域含有光、赤霉素、水杨酸、机械伤害、真菌诱导子、防御和应激反应元件。通过预测发现,HbBBE1蛋白质含有一个信号肽、一个跨膜区域、FAD结合结构域和特异性BBE结构域,它与木薯中的具有相同残基的BBE蛋白质具有80. 1%的相似性。分析HbBBE1基因在橡胶树不同组织中的表达发现,其在乳胶中的表达量最高。白粉病侵染、干旱、高强度光照、过氧化氢、未割胶树割胶处理和机械伤害处理都能显着上调HbBBE1的表达。此外,外源激素赤霉酸、水杨酸、乙烯利、茉莉酸甲酯和脱落酸处理也均可显著诱导HbBBE1的表达。在这些处理中,HbBBE1被赤霉酸刺激后表达量迅速升高,且在0. 5 h达到最大值(6. 3倍)。在脱落酸、乙烯利和过氧化氢等处理下,HbBBE1的表达显著;与未处理的对照相比,其表达倍数达数十倍。综上所述,我们的研究表明HbBBE1在响应橡胶树中的生物和非生物胁迫中起多种作用。Berberine bridge enzyme（BBE,EC1.5.3.9） is a key enzyme in berberine biosynthesis. In this study, HbBBE1 gene was cloned in rubber tree by RT-PCR. The HbBBE1 promoter contained light, gibberellin, salicylic acid, wounding, fungal elicitor, defense, and stress responsive elements. The predicted protein of HbBBE1 contains a signal peptide, a trans membrane region, an FAD binding domain, and a BBE domain which is found specifically in the berberine bridge enzymes and berberine bridge-like enzymes. It shared the highest similarity with BBE protein from Manihot esculenta with 80.1% identical residues. Comparing expression among different tissues of rubber tree demonstrated that HbBBE1 has a particularly high expression level in the latex. HbBBE1 expression was significantly upregulated by biotic and abiotic stress, i.e. powdery mildew infection, drought stress, high intensity light irradiation, H 2O 2, and both tapping treatment in virgin trees and mechanical wounding in seedlings. Furthermore, HbBBE1 transcript was remarkably induced by application of exogenous hormones, including gibberellic acid（GA 3）, salicylic acid（SA）, ethephon（ET）, methyl jasmonate（MeJA）, and abscisic acid（ABA）. Among these treatments, HbBBE1 transcript was quickly induced by GA 3 stimulation, and reached a maximum（6.3-fold） at 0.5 h. The increased expression of HbBBE1 was highly induced by ABA, ET, and H 2O 2 stimuli, and it accumulated dozens of times comparing that at the untreated control.To summarize, our study suggested that HbBBE1 played multiple roles in response to biotic and abiotic stress in rubber tree.

关 键 词：巴西橡胶树 小蘖碱桥酶 HbBBE1 逆境响应 

分 类 号：S794.1[农业科学—林木遗传育种]