作　　者： ; ;

机构地区： 广东海洋大学农学院

出　　处： 《西北农业学报》 2007年第2期65-69,共5页

摘　　要： 根据已知的NBS-LRR类抗病基因蛋白质的保守序列设计简并引物,用以扩增甘薯基因组中的抗病基因同源序列,获得一条大小约500 bp的扩增片段,克隆测序后得到20个NBS-LRR类抗病基因同源片段RGAS。其推导的氨基酸序列均具有P-loop、Kinase-2a和Kinase-3a及GLPL区等几个保守区,并且可分为TIR-NBS-LRR和non-TIR-NBS-LRR两个亚类。其中10个TIR亚类RGAS与已克隆的N、L6、M等抗病基因相应区段的氨基酸序列的同源性为21%-44%,而10个non-TIR亚类RGAS与已克隆的Prf、RPM1、RPS2等抗病基因相应区段的氨基酸序列的同源性为15%-46%。这些抗病基因同源片段(RGA)可做为分子标记筛选甘薯的抗病候选基因。 The degenerate primers were designed based on the conserved NBS-LRR motifs among the known disease-resistance genes. The primers were used to amplify the disease-resistance gene analogues （RGAs） in Sweet Potato （Ipomoea batatas）. A PCR product about 500 bp.was obtained. After cloning and sequencing, 20 NBS-LRR type RGAs in sweet potato were detected. The deduced amino acid sequences of the DNA fragments contained the conserved motifs of NBS-LRR type RGAs , such as P-loop, Kinase 2a, kinase 3a and GLPL domains. These 20 RGAs could be sorted into two distinct types, TIR-NBS-LRR type and non-TIR-NBS-LRR type. When the sequences of 10 TIR type RGAs were compared with known resistance gene （ N , L6 , M etc. ）sequences , the percentage of aminoacid identity was ranged from 21%-44 %, While the other 10 non-TIR type RGAs had 15%-46% homologous compared with known resistance gene （Prf,RPM1 ,RPS2 etc. ）. The R.GAs may further be used as molecular marker for screening of candidate disease-resistance genes in sweet potato.

关 键 词： 甘薯 同源序列 抗病基因

领　　域： [农业科学]