小麦丙氨酸氨基转移酶基因TaAlaAT1的克隆及表达特征分析  

Cloning and expression analysis of alanine aminotransferase gene TaAlaAT1 in wheat infected with stripe rust fungus

作　　者：段迎辉[1] 郭军[1] 王淑娟[1] 于秀梅[2] 黄丽丽[1] 康振生[1,3] 

机构地区：[1]西北农林科技大学植物保护学院,杨凌712100 [2]西北农林科技大学生命科学学院,杨凌712100 [3]陕西省农业分子生物学重点实验室,杨凌712100

出　　处：《植物病理学报》2009年第2期139-146,共8页Acta Phytopathologica Sinica

基　　金：国家"973"前期专项(2006CB708208);教育部长江学者和创新团队发展计划资助(IRT0558);教育部科学技术研究重点项目(107104);国家自然科学基金资助项目(30671350);高等学校学科创新引智计划资助项目(B07049)

摘　　要：在已构建的受条锈菌(Puccinia striiformis f.sp.tritici)诱导的小麦非亲和抑制差减杂交(suppression subtractive hybridization,SSH)文库中,筛选到1个与水稻丙氨酸氨基转移酶基因高度相似的表达序列标签(expressed sequence tag,EST),利用电子克隆与RT-PCR相结合的方法,从小麦中获得1个1563bp的cDNA序列,命名为TaAlaAT1。序列分析表明,TaAlaAT1包含1个完整的开放阅读框,长1440bp,推测编码479个氨基酸。该氨基酸序列具有氨基转移酶的保守特征,与水稻、葡萄、大豆、拟南芥、苜蓿等多种植物的丙氨酸氨基转移酶高度相似,其中与水稻的亲缘关系最近。半定量RT-PCR与实时定量PCR结果显示,TaAlaAT1在小麦与条锈菌互作的非亲和组合中总体呈上调表达,在亲和组合中呈下调表达,且在2个组合中的表达差异显著。推测TaAlaAT1参与了小麦对条锈菌的防御反应。There is increasing evidence that some genes encoding aminotransferase associated with plant carbon and nitrogen metabolism also play critical roles in the induction of plant defense against pathogens. An EST, homologous to the rice alanine aminotransferase gene, was isolated from an incompatible suppression subtractive hybridization （SSH） cDNA library of wheat leaves infected with Puccinia striiformis f. sp. tritici. Using in silicon cloning and RT-PCR, a 1 563 bp cDNA sequence was obtained from wheat and designated TaAlaAT1. Sequence analysis showed that TaAlaAT1 included a complete 1 440 bp ORF and encoded a putative protein composed of 479 amino acids. The deduced amino acid sequence was revealed the presence of the conserved aminotransferase signature and highly homologous to alanine aminotransferase in Oryza sativa, Vitis vinifera, Glycine max, Arabidopsis thaliana and Medicago truncatula. The expression pattern of TaAlaAT1 at transcription level was investigated by semi-quantitative RT-PCR and real-time PCR, respectively, which revealed that TaAlaAT1 transcripts were up-regulated in incompatible interaction of wheat and stripe rust, whereas down-regulated in compatible interaction, and apparently different between incompatible and compatible interaction. It was speculated that TaAlaAT1 was involved in wheat defense response to P. striiformis.

关 键 词：小麦 条锈菌 氨基转移酶 克隆 表达 

分 类 号：S435.121.42[农业科学—农业昆虫与害虫防治]