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一个国际科研团队最近报告说，他们首次分离出一个针对小麦叶枯病的天然抗病基因。这将有助于理解植物抗病机制，寻找抵御农作物病害的新方法。 这个名为stb6的基因，人们早在20年前就得知了它的存在，但进行完整测序和克隆还是首次。新研究由英国洛桑研究所和法国国家农业研究院联合进行，论文发表在英国《自然·遗传学》杂志上。 小麦叶枯病是一种重要的真菌病害，其病原体是小麦壳针孢，会使小麦叶片出现病斑，变得干枯和下垂，严重时可导致减产５０％。由于该病原体已对多种抗真菌农药产生了抗药性，对天然抗病机制的研究尤为重要。 stb6基因的图位克隆 stb6基因只对一部分小麦壳针孢菌株有效，这些菌株会分泌一种特定蛋白质，该基因编码的蛋白质能识别它，启动小麦的天然防御体系。 Functional analysis of candidate genes through barley stripe mosaic virus (BSMV)-mediated VIGS 研究人员说，对stb6基因的研究将有助于寻找更多的天然抗病基因。此外，以往发现的植物抗病基因编码的蛋白质往往位于细胞内部，而stb6基因编码的蛋白质位于细胞表面，这一特殊性质可望加深人们对植物抗病机制的理解。 Deployment of fast-evolving disease-resistance genes is one of the most successful strategies used by plants to fend off pathogens1,2. In gene-for-gene relationships, most cloned disease-resistance genes encode intracellular nucleotide-binding leucine-rich-repeat proteins (NLRs) recognizing pathogen-secreted isolate-specific avirulence (Avr) effectors delivered to the host cytoplasm3,4. This process often triggers a localized hypersensitive response, which halts further disease development5. Here we report the map-based cloning of the wheat Stb6gene and demonstrate that it encodes a conserved wall-associated receptor kinase (WAK)-like protein, which detects the presence of a matching apoplastic effector6,7,8 and confers pathogen resistance without a hypersensitive response9. This report demonstrates gene-for-gene disease resistance controlled by this class of proteins in plants. Moreover, Stb6 is, to our knowledge, the first cloned gene specifying resistance to Zymoseptoria tritici, an important foliar fungal pathogen affecting wheat and causing economically damaging septoria tritici blotch (STB) disease10,11,12.
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