洋葱AcPME基因的克隆及序列分析  

Cloning and Sequence Analysis of AcPME Gene in Onion

作　　者：孙亚玲[1,2] 陈立[1,2] 孙雨晴[2,3] 杨妍妍[2] 吴雄[2] 曹辰兴[1] 霍雨猛[2] 

机构地区：[1]山东农业大学园艺科学与工程学院,山东泰安271018 [2]山东省农业科学院蔬菜花卉研究所/山东省设施蔬菜生物学重点实验室/国家蔬菜改良中心山东分中心,山东济南250100 [3]吉林农业大学园艺学院,吉林长春130118

出　　处：《山东农业科学》2017年第6期7-12,25,共7页Shandong Agricultural Sciences

基　　金：国家自然科学基金项目(31201635;31301786;31672165);山东省农业科学院青年英才重点扶持项目

摘　　要：以洋葱花蕾为试材,通过RACE试验获得了Ac PME基因的全长c DNA序列,Gen Bank登录号为JF913196.1。该基因DNA序列包含2 786个碱基,4个外显子,3个内含子,c DNA序列长度为2 228 bp,编码序列长度为2 001 bp,编码666个氨基酸。生物信息学分析显示Ac PME蛋白存在明显的信号肽和跨膜区域(SP/TM)、PMEI结构域和PME结构域,在PME家族分类中属于第Ⅰ类,即含有一个长的N末端前区域(PRO-region)。氨基酸同源比对与系统进化分析表明,Ac PME蛋白与水稻、玉米、高粱等单子叶植物的同源蛋白具有较高的一致性。三维结构模式图显示该蛋白具有一个明显的凹沟,4个果胶结合位点氨基酸残基(T423、Q453、R565和W567),2个活性位点氨基酸残基(D476和D497)。本研究为洋葱Ac PME基因的结构域蛋白互作及功能研究奠定了基础。The sequence of AcPME gene was obtained through rapid amplification of cDNA ends（ RACE）based on the sample of onion flower bud. The Gen Bank accession number was JF913196. 1. The Ac PME genomic DNA consisted of 2 786 bases with 4 exons and 3 introns. The c DNA length was 2 228 bp with a 2 001 bp ORF and encoded 666 amino acids. The bioinformatic analysis showed that the Ac PME protein consisted of a signal peptide and transmembrane domain（ SP/TM）,a PMEI structural domain and a PME structural domain,which belonged to type I with a long N terminal PRO-region in the PME families. The amino acid homologous alignment and phylogenetic tree analysis exhibited that there were higher identities between Ac PME and PME of homologous monocotyledons such as rice,maize and sorghum. The three-dimensional structure map showed Ac PME protein had an obvious shallow cleft,4 amino acid residues（ T423,Q453,R565 and W567） binding to substrate and 2 residues（ D476 and D497） involved in catalysis. The research laid a foundation for the biological functions of AcPME protein and the interactions between PMEI and PME domains.

关 键 词：洋葱 果胶甲酯酶(PME) 克隆 序列分析 

分 类 号：S633.201[农业科学—蔬菜学]