柚cDNA中NBS-LRR类R基因同源序列的分离  

Isolation of NBS-LRR Class Resistance Gene Analogs from Stigma cDNA of Pomelo (Citrus grandis cv. guanxi)

作　　者：黄代青[1] 王平[1] 吕柳新[1] 

机构地区：[1]福建农林大学园艺系

出　　处：《中国农业科学》2004年第10期1580-1584,共5页Scientia Agricultura Sinica

摘　　要：提取柚花柱的总RNA,通过逆转录合成其cDNA,根据已知植物抗病基因(R基因)的NBS保守区设计简并引物,对cDNA进行扩增,获得大小约为500bp的PCR产物,对连接产物进行酶切归类,筛选得到不同类别的克隆12个,并进行了测序。通过序列同源比较分析发现,其中有10个片段属于NBS-LRR类抗病基因的同源序列(RGA),与已知植物R基因相应区段的氨基酸序列的同源性为11.5%～47.1%。Degenerate oligonucleotide primers based on conserved motifs in the nucleotide binding site (NBS) region of known resistance proteins were used to amplify sequences from stigma cDNA of pomelo (Citrus grandis cv. guanxi) at anthesis by polymerase chain reaction (PCR). A bright band of about 500 bp was obtained. After cloning, 12 classes of clones were selected for sequencing. Searching in the GenBank database using BLAST revealed that 10 classes of sequences showed high level of amino acid similarity to several cloned NBS-LRR class plant resistance genes and many RGAs from other plant species. These pomelo resistance gene analogs (RGAs) are all expressed sequences because of coming from cDNA. Therefore, they are valuable probes for screening candidate disease genes in pomelo.

关 键 词：R基因 同源序列 植物抗病 接产 抗病基因 区段 花柱 DNA NBS 同源比较 

分 类 号：S666.3[农业科学—果树学]