番茄NBS LRR抗根结线虫基因同源序列的克隆与分析
Cloning and analysis of root knot nematode resistance gene of NBS LRR analogs from tomato

根据已知抗病基因的NBS LRR保守结构域设计简并引物，从抗南方根结线虫病的番茄材料cDNA中克隆抗病基因同源序列(resistance gene analogs,RGAs)，并通过qRT PCR技术检测RGAs与南方根结线虫侵染的相关性。序列分析发现，2条序列具有NBS LRR保守结构域，分别命名为F5 8和F5 20；保守区域氨基酸比对结果显示，F5 8（GenBank 登录号为MG860907）和F5 20（GenBank 登录号为MG860908）与已知抗病基因保守区域具有很高的相似性，其中F5 8与Mi 1相应区域氨基酸相似性为94%，F5 20与Hero基因相应区域氨基酸相似性为96%。qRT PCR结果发现，F5 8和F5 20在接种南方根结线虫2龄幼虫24 h后其表达量均发生了变化。初步推测F5 8和F5 20为南方根线线虫侵染相关基因同源序列。
Degenerated primers were designed according to the conserved regions of NBS LRR domain from known plant resistance genes. Then these primers were used for amplification of the NBS LRR analogs from Lycopersicon esculentum. Sequence analysis showed that 5 fragments contained the resistance gene analogs,two of which have the ORF region and conserved NBS LRR domain. F5 8 (MG860907) shared 94% identity with the resistance genes of Mi 1, and F5 20 (MG860908) shared 96% identity with the resistance genes of Hero. The quantitative real time PCR results showed that expression of F5 8 and F5 20 was changed after Meloidogyne incognita infection,suggesting that F5 8 and F5 20 might be related with nematode infection.