Cloning and functional characterization of the vec1 resistance gene

第一个资助期的结果是鉴定出几个主要的QTL，控制多种疾病参数，如对拟南芥和芸苔中长孢弧菌引起的全身传播或发育迟缓的抗性。新应用的重点是拟南芥中相关基因的分子鉴定。将寻求不同方法的组合来实现控制宿主抵抗真菌系统传播的基因的克隆。这些方法的基础将是继续对NILs群体进行精细定位，这些NILs只在染色体2上的一个小片段上有所不同，该片段携带至少一个控制传播抗性的基因（vec1）和勃起位点。后者已被证明是导致抗性发育迟缓的原因。在定制的NILs（感染与未感染）中进行精细定位和表达研究将允许识别少量候选基因。为了鉴定vec1，我们将克隆这些基因，并分析它们在易感生态型Ler中互补后对传播抗性的影响。vec1对防御信号的影响将在表达研究和嫁接实验中进行研究。组织学防御反应将在显微镜下进行研究。在现有的芸苔属作物定位群体中，将查找和分析其同源基因与抗性的相关性，从而将我们的结果应用于油菜育种。

The first funding period resulted in the identification of several major QTL controlling multiple disease parameters such as resistance to systemic spread or to stunting caused by V. longisporum in Arabidopsis and Brassica. The focus of the new application is the molecular identification of the responsible gene(s) in Arabidopsis. A combination of different approaches will be pursued to achieve the cloning of a gene which is controlling host resistance against systemic spread of the fungus. The basis of these approaches will be the continuation of fine-mapping in a population of NILs which differ only in a small segment on chromosome 2 which carries at least one gene controlling spreading resistance (vec1) and also the erecta locus. The latter has been shown to be responsible for stunting resistance. Fine-mapping and expression studies in tailor-made NILs (infected vs. non-infected) will allow identifying a small number of candidate genes. To identify vec1 these will be cloned and analysed for their effect on spreading resistance after complementation in the susceptible ecotype Ler. The effect of vec1 on defence signalling will be studied in expression studies and grafting experiments. Histological defence reactions will be studied microscopically. Homologous genes in Brassica will be searched and analysed for their correlation to resistance in existing mapping populations of Brassica crops, which will allow the application of our results in oilseed rape breeding.