云南野生稻中Xa21基因外显子Ⅱ的分离及序列分析  

Isolation and Sequence Analysis of the Xa21 Gene Exon Ⅱ Homologs from Different Species of Wild Rice in Yunnan

作　　者：钱君[1] 程在全[1] 杨明挚[2] 刘继梅[1] 吴成军[1] 黄兴奇[1] 

机构地区：[1]云南省农业科学院生物技术重点实验室,昆明650223 [2]云南大学生命科学学院,昆明650091

出　　处：《遗传》2005年第3期382-386,共5页Hereditas（Beijing)

基　　金：国家自然科学基金重点项目(编号:30069003;30460019);云南自然科学基金项目(编号:2004C0010Z)资助~~

摘　　要：Xa21是已经分离克隆的一个具有广谱抗性的水稻白叶枯病抗性基因,根据已克隆的白叶枯病抗性基因Xa21外显子Ⅱ序列设计特异性引物对云南3种野生稻及其他稻种进行PCR扩增。结果表明,只有普通野生稻(景洪普通野生稻和元江普通野生稻)及长雄野生稻中扩增到了长400bp的目的片段,而疣粒野生稻和药用野生稻及栽培稻中均没有扩增到目的片段。通过序列比较发现所克隆的序列同长雄野生稻的氨基酸序列变化是随机的。The Xa21 gene previously cloned from the wild rice species Oryzae longistaminata confers broad-spectrum resistance to rice leaf blight caused by different strains of Xanthomonas oryzae pv. oryzae. Here we attempted to determine the existence of Xa21 homologs in other wild rice species and rice cultivars and the sequence differences between the homologs. We synthesized specific primers based on the reported Xa21 sequence to amplify homologs of the gene exon Ⅱ from several rice cultivars and three wild rice species in Yunnan Province, China. The fragments cloned from various types of O.rufipogon Griff from Jinghong and Yuanjiang, Yunnan Province, were highly homologous to the reported Xa21 gene exon Ⅱ. However, the fragment was not found in O.officinalis Wall and O.meyeriana Baill Sequence analysis suggested that differences in nucleotides were located randomly in the fragments we cloned.

关 键 词：野生稻 Xα21外显子Ⅱ DNA序列 同源性 聚类分析 

分 类 号：S511.9[农业科学—作物学]