Cloning of candidates disease resistance gene from three wild rice species

chinois. 候选抗性基因克隆策略是克隆植物新抗性基因的重要途径。根据已知NBS-LRR类抗病基因结构中的氨基酸保守区域,设计兼并引物,通过RT-PCR扩增、克隆和测序,从茶陵野生稻,东乡野生稻和小粒野生稻中共获得了11条NBS-LRR类抗病基因同源序列。通过聚类分析可将同源序列分为3类,其中茶陵野生稻中得到1类,东乡野生稻中得到2类,而小粒野生稻中得到3类。但是小粒野生稻包含有其他两种野生稻的序列。三类序列都与水稻抗病基因RPR1具有较高的同源性,有一类氨基酸序列同源性甚至高达88%,可能为其家族成员。利用电子定位将三类序列定位在水稻基因组11号染色体上RPR1附近。根据序列比对分析结果认为其中可能有1～2个新抗病基因。

anglais. The method of cloning by candidate resistance gene is an important way to clone of the resistance gene of plant. We designed degenrate oligonucleotides primers according to amino acid conserved regions of reported plant disease resistance genes which encode protein that have nucleotide-binding site and leucine-rich repeats （NBS-LRR）. Amplified By RT-PCR, and the DNA fragments from amplification cloned into the vector, and sequenced,we have been obtained 11 disease resistance gene analogues from three wild rice species..The analysis of the pbylogenetic tree indicated that 1 class NBS-LRR disease resistance gene analogues from Oryza rufipogon Reserve in ChalinK, 2 classes from Oryzae sativa fspontanea and 3 classes from Oryza rninuta.And the sequences of Oryza rninuta have all the classes of sequence of the others, and the three classes of disease resistance gene analogues have highly homologous with the resistance gene RPR1. and one class was 88% homologous to the disease resistance gene RPR1 as the alignment of the amino acid, possibly as one of the member of RPR1 family. We mapped the sequences in the region near the gene RPR1 in the chromosome 11 of the rice genome by the method of electronic mapping, we think maybe there is one to two new resistance genes according to the result of the analysis of the sequence.