谷子NBS类型抗病基因同源序列的克隆与分析

以谷子(Setaria italica Beauv.)抗锈病植株十里香和感锈病植株豫谷1号为材料,利用抗病基因同源序列(RGA)技术克隆谷子核苷酸结合位点(NBS)类型RGA并进行分析.共获得了3个RGA,分别命名为RUS1-1、RUS1-2、RUS1-3(Resistance against Uromyces setariae-italicae,RUS),它们编码的蛋白质均含有NBS类型抗病基因编码蛋白的共有特征结构域P-loop和Kinase2α.BLASTX分析结果表明,3个RGA的编码蛋白与水稻中含有NB-ARC信号传导结构域的蛋白质、NBS-LRR类型抗病基因等的编码蛋白同源性为47％～66％.聚类分析结果表明,3个RGA属于NBS-LRR类型抗病基因,且与番茄NBS-LRR类型抗病基因12聚为一类.

Clone and Analysis of Analogs of NBS Class Disease Resistance Genes in Setaria italica

Taking Uromyces setariae-italicae resistant cultivar Setaria italica Beauv.Shilixiang and susceptible cultivar Yugu NO.1 as materials,analogs of nucleotide binding site(NBS) class disease resistant gene were cloned by the method of resistance gene analog(RGA).3 NBS-like sequences containing DNA sequences encoding conserved motifs P-loop and kinase 2α,which were the characteristics of NBS type resistant gene’s protein,were obtained and named as RUS(Resistance against U.setariae-italicae)1-1,RUS1-2,RUS1-3.The proteins encoded by these sequences were 47%～66% homologous with protein containing NB-ARC domain of Oryza sativa or NBS-LRR resistance gene’s protein.Phylogenetic analysis indicated that the 3 sequences were NBS-LRR class disease resistant gene and similar to NBS-LRR type disease resistant gene I2 of tomato.