烟草祖先种及重要野生种PDR1基因的生物信息学分析

Bioinfomatics analysis of pleiotropic drug resistance gene PDR1 in ancestors and wild species of Nicotiana tabacum

植物的多向耐药性(Pleiotropic drug resistance,PDR)转运蛋白隶属于ATP结合盒(ATP-binding cassette,ABC)转运蛋白家族的G亚家族。该类蛋白参与植物多种初生、次生代谢物的跨膜运输,在植物的生长发育、响应逆境胁迫、解毒过程中起着重要作用。近年的研究还表明,该蛋白与多种植物对真菌病原的抗性有关。本文以烟草祖先种和重要野生种为研究对象,以拟南芥PDR12蛋白、烟草的PDR1基因为探针,通过搜索同源序列,从数据库中提取烟草及祖先种、重要野生种中的PDR基因、蛋白序列,并通过生物信息学分析手段对其编码蛋白的理化特性、氨基酸序列特征、蛋白结构、功能、启动子序列及表达调控特征进行了分析,并以本氏烟(Nicotiana benthamiana)NbPDR1为代表,预测了该基因启动子的顺式作用元件,以普通烟草(Nicotiana tabacum)NtPDR1基因为例,预测了其基因编辑位点。结果表明,这些PDR基因相似性高,均编码跨膜蛋白,具有典型的跨膜结构域和核酸结合结构域。该基因启动子区有多个与病原真菌诱导、干旱等逆境胁迫响应相关的元件,暗示该基因可能是抗真菌病害、响应逆境胁迫的广谱抗性基因。最后,本文预测的基因编辑位点,为烟草PDR基因的功能研究、基因编辑及抗病育种提供理论基础。

Plant PDR transporters belong to the G subfamily of the ABC transporter family.They are involved in the transmembrane transport of various primary metabolites and secondary metabolites in plants,and play important roles in plant growth and development,stress regulation,and detoxification processes.Recent studies have also shown that PDR proteins are associated with the resistance of various plants to fungal pathogens.In this paper,the PDR gene and protein sequences of tobacco,its ancestor species and important wild species were extracted from the database by searching homologous sequences using the PDR12 protein of Arabidopsis thaliana and the PDR1 gene of tobacco as probes.Their physical and chemical characteristics,amino acid sequence,protein structure,functions,promoter sequence,expression regulation characteristics of its coding protein were analyzed by bioinformatics analysis.Cis-acting element and gene editing sites of NbPDR1 and NtPDR1 were analyzed by bioinformatics tools,respectively.Results showed that those PDR were highly similar in structure,all of which had typical TM (transmembrane domains) and NBD (nucleotide binding domains),with capacity of encoding transmembrane protein.The promoter region of NbPDR1 had several elements related to fungal pathogenic induction,drought and other stress response,which implied this gene may be a broad-spectrum resistance gene for antifungal diseases and stress.The analysis and prediction of gene editing sites provide a theoretical basis for gene editing,functional research and disease resistance breeding of tobacco PDR genes.