西洋参PqERF1基因的克隆和生物信息学分析

Cloning and bioinformatic analysis of PqERF1 gene in Panax quinquefolius

乙烯响应因子(ethylene response factor,ERF)是具有PETALA2(AP2)结构域的转录因子。本研究通过西洋参(Panax quinquefolius L)的转录组高通量测序结果分析获得75条具有AP2结构域的转录因子序列,并克隆到一条开放阅读框为933对碱基的基因序列,定名为PqERF1。基因表达分析结果表明PqERF1基因受茉莉酸甲酯(MeJA)的诱导,这与人参皂苷含量的受诱导模式相同。蛋白结构预测结果表明PqERF1是定位于细胞核的具有完整保守的AP2结构域的转录因子,InterproScan蛋白功能结构域分析结果表明PqERF1很可能为发病机制相关蛋白;序列比对和进化关系分析结果也显示PqERF1与发病机制相关蛋白(烟草NtERF4)、次生代谢产物相关合成蛋白(野胡萝卜DcERF1)和花衰老相关蛋白(矮牵牛PhERF12)的相似性高,且系统进化关系较近。因此,推测PqERF1基因可能是参与西洋参次生代谢产物合成调节、抗病性和衰老相关的重要基因。

ERF family transcription factor（TF） represented ethylene-responsive protein which harbored a conserved AP2 domain.After searching the plant transcription factor database,a total of 75 unigenes was found which contained AP2 domain from the transcriptome dataset of Panax quinquefolius L.One unique sequence of ERF transcript,named as PqERF1,was cloned with entire open reading frame of 933 base pairs（bp）.Protein prediction result indicated that the gene was localized in nucleus and had a conserved AP2 domain.PqERF1 gene could be induced by methyl jasmonate（MeJA） which was consistent to the inducing profile of triterpene ginsenosides.InterproScan prediction indicated that PqERF1 was probably a pathogenesis-related gene.Sequence alignment and phylogenetic analysis demonstrated PqERF1 was with high identity and had relative close relationship to the NtERF4（Nicotiana tabacum）,PhERF12（Petunia x hybrida） and DcERF1（Daucus carota） which was related to plant defense,regulation of secondary metabolism and the flower senescence respectively.Therefore,the gene was likely involved in regulation of secondary metabolism,plant defense and physical processes which would provide gene resource for further study on secondary metabolite synthesis and molecular breeding of P.quinquefolius.