水稻白叶枯病菌糖基化岛GI基因的分子鉴定  

Molecular identification and homology analysis of genes clustered in a genomic glycosylation island of Xanthomonas oryzae pv.oryzae.

作　　者：孙艳伟[1,2] 文景芝[1] 吴茂森[2] 陈华民[2] 何晨阳[2] 

机构地区：[1]东北农业大学农学院,哈尔滨150030 [2]中国农业科学院植物保护研究所,植物病虫害生物学国家重点实验室,北京100193

出　　处：《东北农业大学学报》2009年第8期18-22,共5页Journal of Northeast Agricultural University

基　　金：中央财政国家重点实验室自主研究课题专项(SKL2007SR06)

摘　　要：为了阐述水稻白叶枯病菌（Xanthomonas oryzae pv．oryzae，Xoo）糖基化岛（Glycosylation Island，V1）基因的结构特征以及可能的生物学功能，研究通过基因克隆和序列分析，对G，基因结构特征进行了鉴定：通过与铜绿假单胞菌（Pseudomonos aeruginosa，Pa）a型短甜基因的比较，对XooGI基因进行了功能推测分析。用特异性引物进行PCR扩增，从野生型菌株PX099A基因组中克隆了10个G，基因序列。该G，插在鞭毛基因簇中，上游为转录调控因子基因fleQxoo，下游为鞭毛基体蛋白基因fliExoo。GI基因均为单拷贝，转录方向相同。GI基因核苷酸序列在Xoo和Paa型短岛中同源性达41．98％-78．58％，其中糖基转移酶基因rbfC具有保守结构域（Glycos—transf_2），在病原黄单胞中同源性较高。在G，基因启动子中存在or“保守结合序列GG-（N10）-Gc和转录调控因子FleQxoo结合序列CC-（N4）-C-（N4）-T。因此，XooGI可能具有进化上的结构和功能保守性；其基因转录可能受到盯”和FleQxoo的直接调控。To better understand the structural and putative functional characterization of glycosyla- tion island （GO in Xanthomonas oryzae pv.oryzae （Xoo）, the casual pathogen of bacterial blight of rice, the gene cloning, sequencing analysis and comparing analysis with corresponding genes in Pseudomonas aeruginosa （Pa） of Xoo GI genes were performed. Ten G/genes were successfully cloned from genomic DNA of the wild-type PXO99A by using specific primers. The GI was inserted in flagellar gene cluster, between transcriptional regulatr gene fleQ and flagellar body protein gene fliE. All the G/genes were single-copy, with the same transcriptional direction. The nucleic homology of G/was 41.98%-78.58% between Xoo and Pa, but rbfC, which encoding glycosyltransferase with Glycos_transf. 2 conserved domain, had a high nucleic homology. Both conserved binding sequences of σ54 and FleQ, GG-（N10）-GC and CC-（N4）-C-（N4）T respectively, were found in the promoter region of GI genes. Therefore, the structure and function of GI in Xoo possibly had evolutional conservatism, transcription of GI genes was under the direct regulation of σ54 and FleQ.

关 键 词：水稻白叶枯病菌 糖基化岛 基因克隆 结构特征 糖基转移酶 

分 类 号：S511[农业科学—作物学] S435.11