摘要
为了克隆条锈菌诱导上调表达的小麦腺苷甲硫氨酸脱羧酶(SAMDC)基因并研究其在小麦感病、抗病单株苗期抗条锈病防御反应中的作用,以大麦(Hordeum vulgareL.)SAMDC全长cDNA序列为信息探针,采用电子克隆、RACE(Rapid amplification of cDNA ends)和RT-PCR方法,从条锈菌(Puccinia stri-iformisf.sp.tritici)CYR32侵染的小麦(Triticum aestivumL.)抗条锈病新种质NR1121中分离出1个新的小麦SAMDC基因家族成员,命名为TaSAMDC2(GU016570)。TaSAMDC2基因cDNA序列全长2 003 bp,5′非翻译区区域和一个带有Poly(A)的3′非翻译区区域长分别为553和283 bp;该基因的开放阅读框为1 167 bp,编码388个氨基酸,编码的氨基酸序列包含酶原剪切位点和PEST结构域。基因组序列全长2 539bp,位于5′UTR存在一个526 bp长的内含子序列,内含子的剪切位点均符合真核生物GT-AG规则。同源序列分析表明,TaSAMDC2与来自大麦、水稻(Oryza sativaL.)、玉米(Zea maysL.)、一粒小麦(TriticummonococcumL.)4种植物SAMDC蛋白的相似性分别为95.0%、85.0%、80.0%和80.0%。半定量RT-PCR与实时荧光定量PCR分析表明,TaSAMDC2的表达受条锈菌诱导,小麦苗期经条锈菌侵染后,在抗病材料中,该基因于48 hpi上调表达至最高水平,而在感病材料中先下调、上调表达至最高水平明显滞后。结果提示,分离到的是一个条锈菌CYR32诱导后上调表达的小麦SAMDC基因,该基因可能参与了小麦的抗条锈病反应。
S-adenosylmethionine decarboxylase（SAMDC）gene from wheat induced by stripe rust pathogen（Puccinia striiformis f.sp.tritici） was isolated to better understand the resistance response at wheat seedling stage.With the complete cDNA sequence of barly（Hordeum vulgare L.） SAMDC gene as probe,a new wheat SAMDC gene designated as TaSAMDC2（GenBank accession： GU016570）） were isolated from resistant germplasm NR1121（Triticum aestivum L.） induced by stripe rust pathogen CYR32 using in silico cloning,RT-PCR and RACE techniques.The complete cDNA sequence of TaSAMDC2 was 2003 bp in length with its 5′ untranslated region（5′-UTR） and 3′ untranslated region（3′-UTR） with Poly（A） of 553 and 283 bp,respectively.The open reading frame（ORF） of TaSAMDC2 gene was 1167 bp and encoded 388 amino acids containing conserved sequence with the proenzyme cleavage site and one typical conserved PEST domain of pathogenesis related protein SAMDC family.The complete genomic DNA sequence of TaSAMDC2 was 2 539 bp in length with 526 bp intron with the splicing sites of GT-AT bi-nucleotidesequence in its 5′-UTR.Homologous analysis found that TaSAMDC2 were 95.0%,85.0%,80.0% and 80.0% of sequence similarity with SAMDC proteins from barley（Hordeum vulgare L.）,rice（Oryza sativa L.）,Maize（Zea mays L.） and wheat（Triticum monococcum L.）,respectively.Expression of TaSAMDC2 transcripts was performed by semi-quantitative reverse transcription polymerase chain reaction（RT-PCR） and real time quantitative RT-PCR.The results revealed that TaSAMDC2 transcription was up-regulated and reached the peak at 48hpi in the wheat seedling inoculated with CYR32.TaSAMDC2,a new up-regulated SAMDC gene from wheat induced by CYR32,was isolated and it may participate in defense response of wheat resistance to stripe rust pathogen.
出处
《麦类作物学报》
CAS
CSCD
北大核心
2011年第5期811-818,共8页
Journal of Triticeae Crops
基金
国家重大基础研究规划(973)项目(2006CB708208)
陕西省"13115"科技创新工程项目(2008ZDKG-07)
关键词
小麦
条锈菌
腺苷甲硫氨酸脱羧酶
基因克隆
表达模式
Wheat
Puccinia striiformis f.sp.tritici
S-adenosylmethionine decarboxylase（SAMDC）
Gene cloning
Expression pattern
