【摘要】 根据已知的 NBS- L RR类及丝 /苏氨酸蛋白激酶类抗病基因结构中氨基酸的保守区域 ,设计了两组简并引物用于扩增广谱抗稻瘟病品种云系 2号中的抗病基因同源序列。结果一共获得 11类的 NBS- L RR类抗病基因同源片段及 16类的丝 /苏氨酸蛋白激酶类抗病基因同源片段。所有 11类的抗病基因同源系列均含有 NBS- L RR类抗病基因的保守序列 ,如 P-loop、Kinase 2、Kinase 3a以及跨膜区域等。所有 16类的蛋白激酶的序列均含有丝 /苏氨酸蛋白激酶所共有的催化区 (共有氨基酸序列 :DL KPEN)、 (共有氨基酸序列 :GT/ SXXYXAPE)以及蛋白激酶的其他催化区。两条 NBS- L RR类的抗病基因同源片段 YR1、YR12分别与抗病基因 I2 C- 2及 Xa1氨基酸同源性很高 (>5 0 % )。7条丝 /苏氨酸蛋白激酶类的抗病基因同源片段与已克隆的 Xa2 1、Pto、L r10等抗病基因的氨基酸序列超过 6 0 %的相同以及 76 %～ 78%的氨基酸类似更多还原

【Abstract】 Two sets of degenerate oligonucleotide primers were designed on the basis of nucleotide binding site (NBS) motifs conserved among the disease resistance genes Xa1, RPM1, RPS2, N, L6, Pib, I2C, Prf, M, and serine/threonine protein kinase (STK) motifs conserved among the disease resistance genes Pto, Fen, Lr10, Xa21, respectively. The primers weresubsequentlyused as PCR primers to amplify resistance gene analogues in a high blast resistant rice cultivar Yunxi 2 (Oryza sativa L.). Sequencing of amplification products indicated that at least 11 classes of NBS resistance gene analogues and 16 classes of STK resistance gene analogues were detected. All of NBS resistance gene analogues contained the conserved motifs of NBS LRR type resistance genes, such as P loop (Kinase 1a), Kinase 2, Kinase 3a and transmembrance domain. All of STK resistance analogues contained the catalytic domains of serine/threonine protein kinase, such as Ⅰ to Ⅴ, Ⅵ (consensus sequence: DLKPEN), Ⅶ, Ⅷ(consensus sequence: GT/SXXYXAPE) and Ⅸ. YR12 showed significant amino acid homology (63% identify and 77% similarity) to blight resistance gene Xa1 of rice to Xanthomonas oryzae pv. oryzae. YK19 exhibited 52% deduced amino acid identify and 67% similarity to resistance gene Xa21 of rice to Xanthomonas oryzae pv. oryzae. YK13,YK21,YK25 and YK26 showed significant amino acid homology (61%-64% identify and 76%-78% similarity) to resistance gene Lr10 of wheat to Puccinia recondita. YK1 showed 60% identify and 76% similarity to resistance gene Pto of tomato to Peseudomonas syringae pv. tomato.更多还原