【摘要】 目的:克隆甜瓜抗枯萎病基因同源序列并对其序列分析。方法:根据已发表的甜瓜抗枯萎病基因Fom-2设计引物,从高抗枯萎病甜瓜品种‘日本安农二号’基因组中扩增Fom-2同源序列R-Fom-2。结果:该基因长3307bp,包含一个完整的开放阅读框,编码1073个氨基酸,推测蛋白质分子量123.57kDa,等电点7.06。属于nonTIR-NBS-LRR类抗病基因,在LRR区存在一个可能的CC结构域。但在nonTIR类抗病蛋白中,CC结构域一般位于kin-1a前。氨基酸同源性分析显示,R-Fom-2同Fom-2全长序列具有96%的同源性,对不同甜瓜品种Fom-2的LRR区分析比较,同源性在91%以上。且LRR区的差异主要集中在β-strand/β-turn区域。结论:序列分析揭示Fom-2家族是一个活跃的基因,LRR区可能对Fom-2家族的功能起着重要作用,为进一步研究R-Fom-2基因的结构与生物学功能奠定了基础。更多还原

【Abstract】 Objectives:To clone and sequence analysis of resistance to Fusarium wilt gene analogs from melon.Methods: R-Fom-2 fragment was amplified by PCR from the melon ’Japan annong-2 ’of high resistance to Fusarium wilt and was then analysed by sequence.Results: The R-Fom-2 sequence is long 3307bp.The Putative protein molecular weight is 123.57kD with an isoelectric point of 7.06 including a full ORF which encodes 1073 amino acids.R-Fom-2 which belongs to the nonTIR-NBSLRR resistance gene.It has a potential cc structure in LRR which is usually in front of kin-1a among nonTIR-NBS-LRR proteins.Sequence homology analysis of amino acid showed that R-Fom-2 shared high homology(96%) with Fom-2 and had a similarity over 91% compared with different melon breeds in Fom-2 LRR.Conclusion:The difference of LRR which mainly located on the β-strand/β-turn reigns indicated Fom-2 is a active gene and LRR has an important influence on Fom-2 function, and will be the foundation for the preparation of studying structure and biological functions.更多还原