长春花小叶病植原体质粒DNA克隆及其分子特征  

Complete Sequence of a Full-length DNA and Molecular Characterization of one Plasmid from Periwinkle Little Leaf Phytoplasma

作　　者：郑文虎[1,2,3,4] 车海彦[2,3,4] 符瑞益[2,3,4] 杨毅[2,3,4] 罗大全[2,3,4] 

机构地区：[1]海南大学环境与植物保护学院,海南海口570228 [2]中国热带农业科学院环境与植物保护研究所,海南儋州571737 [3]农业部热带作物有害生物综合治理重点实验室,海南儋州571737 [4]海南省热带农业有害生物监测与控制重点实验室,海南儋州571737

出　　处：《热带作物学报》2012年第1期94-98,共5页Chinese Journal of Tropical Crops

基　　金：中央级科研院所基本科研业务费专项(No.2011hzs1J007);农业科技成果转化资金项目"槟榔黄化病快速诊断技术体系推广示范"(No.2010 GB23260573);海南省自然科学基金项目(No.310069);中国热带农业科学院环境与植物保护研究所引进人才科研启动基金项目(No.Hzs1004);海南大学(‘211工程’)建设项目

摘　　要：为了测定长春花小叶病植原体质粒及分析其分子特征,扩增长春花小叶病植原体质粒片段,然后进行反向扩增,拼接得到质粒全序列,且预测质粒编码蛋白的跨膜区、亚细胞定位等。结果表明,获得的质粒全长为4 102 bp,A+T含量为75.18%,编码5个蛋白,且将该质粒命名为pPLLHn-1。其中ORF的2、3、4编码蛋白分别含有2、1、2个跨膜区,ORF3的信号肽(Singnal peptide,SP)的信号值为0.948,ORF3编码的氨基酸序列与洋葱黄化植原体质粒EcOYW1参与质粒拷贝数控制的蛋白(Copy number control protein)具有97%的同源性。此结果说明长春花小叶病植原体质粒pPLLHn-1编码的5个蛋白中,除与质粒复制有关的RepA和SSB外,另外3个均为跨膜蛋白,根据分泌蛋白的特征分析初步推断ORF3蛋白为分泌蛋白。DNA fragments of the plasmid（pPLLHn-1）in Periwinkle little leaf phytoplasma Hainan strain（PLL-Hn）were amplified with primer pairs which were designed according to plasmid sequences published on NCBI.Transmembrane domain and subcellular localization predictions of proteins encoded by the plasmid among the pPLLHn-1 plasmid sequences were completed by using bioinformatic softwares.The plasmid comprised 4 102 bp and had a nucleotide content of 75.18% A＋T and encoded five ORFs.ORF2,ORF3 and ORF4 of pPLLHn-1 contained 2,1 and 2 tranmembrane domains respectively,and signal peptide values of ORF3 was 0.948.Homologous comparison showed that Cop homology between ORF3 and the Cop of EcOYW1 was 97%.Two ORFs of the pPLLHn-1 plasmid encoded a replication associated protein（RepA）and a single-stranded DNA binding protein（SSB）,respectively.Other three putative proteins encoded by the plasmid were predicted to contain one or more transmembrane domains respectively.According to the characteristics of secreted proteins,ORF3 protein was concluded a secreted protein.

关 键 词：长春花小叶病 植原体 质粒 克隆 序列分析 

分 类 号：S432.1[农业科学—植物病理学]