橡胶树皮乳管组织茉莉酸诱导相关因子AP2/EREBP基因的克隆与表达分析

Cloning and Characterization of Jasmonic Acid-Induced AP2/EREBP Genes in Laticifer from Rubber Tree (Hevea brasiliensis Muell. Arg.)

茉莉酸(jasmonic acid,JA)可诱导橡胶树(Hevea brasiliensis Muell.Arg.)乳管分化,是乳管分化的关键信号分子。目前,对JA诱导橡胶树乳管分化的分子机理仍然不清楚。在前期研究中通过筛选JA刺激乳管分化时期的橡胶树树皮组织cDNA差减文库,获得了4条与茉莉酸诱导乳管分化相关的AP2/EREBP家族转录因子基因的EST。该研究在此基础上,采用RACE法完整地克隆了这4个AP2/EREBP转录因子基因的开放阅读框,蛋白氨基酸序列分析表明其中3个属于ERF亚类,1个属于RAV亚类;表达分析发现,这4个基因在乳管分化时期的橡胶树树皮组织的表达受JA诱导,随JA处理时间的延长,其表达量先增强后减弱,推测它们可能在JA诱导橡胶树乳管分化过程中起着重要的调控作用。

Jasmonic acid （JA） can significantly induce the laticifer differentiation of rubber tree（Hevea brasiliensis Muell. Arg.）. However, little is known about the molecular mechanism during jasmonie-induced laticifer differentiation. In previous study, we obtained 4 ESTs of AP2/EREBP transcription factor genes by scanning differentially expressed genes from a forward suppression subtractive hybridization （SSH） eDNA library of barks, which were stimulated by JA at laticifer differentiation stage. In this study, we isolated these 4 cDNAs with complete open reading frames （ORFs） encoding AP2/EREBP proteins using RACE technique from barks of rubber tree. Amino acid structures analysis indicated that three of them belonged to ERF subgroups, and the remained one was RAV subgroups member. Expression analysis revealed that these 4 genes were all induced by JA in barks during JA-induced laticifer differentiation, and they were all strongly up-regulated and then decreased along with the treatment with JA. These results indicate that AP2/EREBP genes of rubber tree might be involved in JA-induced laticifer differentiation.