摘要
由布氏白粉菌(Blumeria graminis f. sp. tritici,Bgt)引起的小麦白粉病是危害我国主产麦区的主要病害之一,防治失时严重影响籽粒产量。抗病基因在小麦应对白粉菌胁迫的应答转录调控过程中起着至关重要的作用,但目前具体的调控机理尚不明确。本研究从小麦品种N9134的RNA-seq Library中获得了白粉菌侵染不同时期差异表达的两个Unigenes,利用反转录PCR(reverse transcription polymerase chain reaction,RT-PCR)克隆了两个基因的cDNA全长序列,生物信息学分析表明,两个Unigene是来源于bZIP家族的TGA转录因子,分别命名为TaTGA1a和TaTGA1b (GenBank:KU746662和KU746663)。TaTGA1a基因组序列包含8个内含子和9个外显子,编码基因由4AS-5969591转录而来; TaTGA1b包含9个内含子和10个外显子,由4BL-7004698转录而来。TaTGA1a/b编码同一段含有312个氨基酸的多肽,分子量约为35 kD。利用实时荧光定量PCR(quantitative real-time polymerase chain reaction,qRT-PCR)分析基因在白粉菌胁迫下的表达情况,以明确其表达和生物调控模式,结果表明:用白粉菌生理小种E09接种苗期N9134后TaTGA1a和TaTGA1b均响应了白粉病菌的胁迫。其中TaTGA1b在早期上调表达表现正调控,而TaTGA1a的表达呈现先降后升的特异调控模式。两者对白粉菌胁迫不同的响应转录模式暗示TaTGA1a/b基因在植物对白粉菌侵染的防御过程中可能起着不同的作用,为进一步的功能研究奠定了基础。
Powdery mildew of wheat,caused by Blumeria graminis f.sp.tritici,is one of the major disease in wheat-producing region in China leading to severe yield losses when lack of effective control.The transcription and its regulation of resistance genes has a crucial role in response to challenge of powdery mildew s,although its exact functions remain unclear.In this study,two unique genes with differential expression level during the infection time course were identified after screening of the wheat N9134RNA-Seq library with infection of powdery mildew pathogen.The full-length cDNAs of the two genes were obtained using RT-PCR (reverse tran- scription polymerase chain reaction)system.Following analysis by bioinformatics tools,these two transcripts were identified encoding putative TGA transcription factor belong to the bZIP (basic-domain leucine-zipper) family,and the two genes were named TaTGAla and TaTGAlb (GenBank:KU746662and KU746663,respec- tively),which the products shared the same protein of 312aa.The molecular weight of the polypeptide wasapproximately 35kD.The rigorous alignment results showed that the TaTGAla and TaTGAlb were transcribed from 4AS-5969591and 4BL-7004698,respectively.The genomic DNA of the TaTGAla consisted of 8 introns and 9 exons,while the TaTGAlb contained 9 introns and 10exons.The transcription analysis by qRT-PCR indi- cated that both TaTGAla and TaTGAlb involved in plant defense against Bgt race E09 infection at seedling stage of wheat line N9134.However,the patterns of expression varied between two genes,which TaTGAlb was kept on up-regulation,while TaTGAla was inhibited at first and later triggered.This kind of phenomenon implied that the TaTGAla played a different role from TaTGAlb in plant defense against the Bgt pathogen infection.Our study might provide new clues for future functional and molecular research regarding wheat-fungus interactions.
作者
徐仲阳
张宏
莫启波
吕士凯
王长有
吉万全
XU Zhong-yang;ZHANG Hong;MO Qi-bo;LU Shi-kai;WANG Chang-you;JI Wan-quan(College of Agronomy,Northwest A&F University,Yangling 712100,China;State Key Laboratory of Plateau Ecology and Agriculture,Qinghai University,Xining 810016,China)
出处
《植物病理学报》
CAS
CSCD
北大核心
2018年第6期766-777,共12页
Acta Phytopathologica Sinica
基金
国家重点研发计划(2017YFD0100701)
陕西省科技统筹创新工程计划项目(2015KTZDNY01-01-02)
唐仲英基金(2017TZY004)
关键词
小麦
TGA转录因子
白粉病
免疫抗性
基因表达
Wheat
TGA transcription factor
Powdery mildew
Immune resistance
Gene expression