小麦诱导抗性基因TaWIR1b的克隆及表达分析

摘要

全蚀病是小麦上一种重要的土传病害.选育和种植抗病品种是防治小麦全蚀病的根本途径,抗病基因研究是抗病育种的基础性工作.根据基因TaWIR1b (Accession no.M94959.1)的全长序列设计引物扩增‘新农19’的cDNA,获得了完整ORF,编码85个氨基酸残基,比对后发现与TaWIR1b序列同源性达100％.根据获得的TaWIR1b基因全长序列设计定量引物,分析TaWIR1b在全蚀菌胁迫条件下不同互作模式的表达特征.结果表明接种全蚀病菌后抗病小麦品种‘新农19’中TaWIR1b基因被诱导表达,接菌后3d达到峰值143.97,感病品种‘新麦19’中峰值出现在接菌后8d,表达量仅为对照的4.22倍,提示该基因可能参与小麦对全蚀病的抗病过程.%Take-all disease,caused by Gaeumannomyces graminis var.tritici (Ggt),is one of the important soilborne diseases of wheat.It is the fundamental way to breed and plant resistant varieties for preventing the disease,and research on resistance genes is the foundation for resistance breeding.In this study,a complete ORF (open reading frame),with 100％ homology with TaWIR1b from GenBank,was obtained by amplifying cDNA of'Xinnong19 ’ using primers designed based on TaWIR 1b sequence (Accession no.M94959.1).Primers were synthesized for analyzing the transcription patterns of the gene by quantitative PCR in different wheat-pathogen interaction patterns induced by Ggt.The results indicated that TaWIR 1b was induced by Ggt up-regulation expression in resistant cultivar ‘Xinnong19',with a peak value of 143.97 three days post inoculation,but the peak value was 4.22 at 8 d post inoculation in susceptible cultivar'Xinmai19'.It indicates that the gene TaWIR 1b might be involved in the course of resistant response to take-all disease.