【摘要】 为深入研究小麦 (TriticumaestivumL .)的抗白粉病机制 ,应用反转录PCR(Reverse -TranscriptionPolymeraseChainReaction ,RT -PCR)和cDNA文库筛选技术 ,从抗白粉病小麦 -簇毛麦 6VS/6AL易位系 (wheat-Haynaldiavillosa6VS/6ALtranslocationline)中分离到一个小麦类甜蛋白基因的全长cDNA。该基因编码由 173个氨基酸残基组成的酸性多肽。经蛋白质一级结构推导分析 ,它与植物中已分离的类甜蛋白高度同源 ,将其命名为TaTLP1基因 (Gen Bank登录号 :AF3 84146)。Northern分析发现 ,该基因在抗病的小麦 -簇毛麦 6VS/6AL易位系及感病的“扬麦 5号”中的表达水平有明显差异。Western分析表明 ,在小麦叶片中TaTLP1的表达产物是分子量约为 160 0 0道尔顿 (16kDa)的可溶性细胞质蛋白 ,并受白粉菌 (Erysiphgraminis)诱导表达。研究发现 ,TaTLP1的表达量在抗病的 6VS/6AL易位系中比在感病的“扬麦 5号”中明显高。从蛋白质水平上证实该类甜蛋白可能与小麦 6VS/6AL易位系的抗白粉病性相关。Southern分析显示 ,TaTLP1基因在小麦基因组中有 1～ 2个拷贝。利用中国春缺体 /四体系分析 ,已将TaTLP1基因定位在小麦 7B和 7D染色体上更多还原

【Abstract】 To understand wheat powdery mildew resistance mechanism,reverse-transcription polymerase chain reaction (RT-PCR) and cDNA library screening were performed to isolate the full-length cDNA of wheat thaumatin protein gene from wheat-Haynaldia villosa 6VS/6AL translocation line.The putative amino acid sequence of this gene consists of 173 amino acid residues,and is an acid polypeptide.It was highly homologous to thaumatin proteins isolated from other plants,so it is designated as TaTLP1(GenBank accession number:AF384146).Northern blot analysis of TaTLP1 showed that the transcription difference obviously existed between resistant wheat- Haynaldia villosa 6VS/6AL translocation line and susceptible "Yangmai 5".The result of western blot showed that the protein expression product of TaTLP1 gene in wheat seedling leaf was a soluble cytoplasm protein,whose expression was induced by fungus Erysiph graminis and apparently related to disease resistance of the 6VS/6AL translocation line.Southern blot indicated that the TaTLP1 gene had 1～2 copies in wheat genome,and had been localized on the specific region of 7B and 7D chromosomes in wheat.更多还原