瓜枝孢弱毒菌株诱导黄瓜抗病相关基因表达的cDNA-AFLP分析  

Analysis of Disease Resistance Related Genes Expression in Cucumbers Inoculated by Cladosporium cucumernium Using cDNA-AFLP Method

作　　者：汪海军[1] 沈镝[1] 石延霞[1] 李锡香[1] 李宝聚[1] 

机构地区：[1]中国农业科学院蔬菜花卉研究所,北京100081

出　　处：《园艺学报》2010年第3期421-427,共7页Acta Horticulturae Sinica

基　　金：国家自然科学基金项目(30370983);农业部园艺作物遗传改良重点开放实验室项目

摘　　要：利用cDNA-AFLP技术,分析瓜枝孢弱毒菌株诱导黄瓜苗后72h内抗病相关基因的差异表达。结果显示,诱导的基因表达差异始于接种后3h,接种后6h差异表达片段总数达到高峰。8个取样时间点的诱导性差异表达片段数大于抑制性表达片段数。仅在接种后第12h呈现相反趋势。通过回收、克隆、测序和同源性比对,获得的5个片段分别与拟南芥中病原菌诱导的水杨酸糖基转移酶、梨磷脂酶C编码的基因等具有较高的同源性,初步推断瓜枝孢弱毒菌株诱导黄瓜抗病可能是通过依赖于水杨酸介导的信号传导途径诱导黄瓜的系统抗病性(system acquired resistance,SAR),作为胁迫抗性信号传递中的关键酶——磷脂酶C可能参与了上述过程。经Northern杂交结果证实,克隆分离的DNA差异片段是瓜枝孢弱毒菌株诱导表达的特异片段。The expression of disease resistance related genes in cucumber（Cucumis Sativus L.） seedlings inoculated by Cladosporium cucumernium strain with weak virulence was analyzed among 72 hours by cDNA-AFLP method in this study.The results showed that the difference of gene expression began at 3 hours after inoculation,and the number of differential expression fragments reached the maximum at 6 hours after inoculation.The number of induced gene fragments was more than that of inhibited gene fragments at 8 time points after inoculation,but the results was not the same at 12 hours after inoculation.Through recovery,cloning,sequencing and homology analysis,5 obtained fragments share high homology with salicylic acid glucosyltransferase,Pyrus communis phosphatidyl glycerol specific phospholipase C-like mRNA,etc.respectively.We concluded that disease resistance of cucumber induced by inoculation of Cladosporium cucumernium strain with weak virulence might depend on signal transduction pathway mediated by salicylic acid,further induce system acquired resistance（SAR）.Phospholipase C,as one of the key enzyme of signa transduction in stress tolerance,could be involved in the process described above.Northern blot results further proved the differential fragments was induced by the inoculation of Cladosporium cucumernium.

关 键 词：黄瓜 瓜枝孢弱毒菌株 CDNA-AFLP 诱导抗病 差异表达 

分 类 号：S642.2[农业科学—蔬菜学]