摘要
以抗白粉病品系“百农 32 17×Mardler” BC5F4为材料 ,构建了一个白粉病菌接种初期的抑制消减杂交cDNA文库 ,测序获得 76 0条ESTs。与GenBank序列进行BLASTx分析 ,获功能已知ESTs 2 71条。通过分析抗病相关基因 ,推测G蛋白介导的信号传导途径、SA信号传递系统、MAP相关信号传递系统等参与了小麦抗白粉病过程。SAR基因在抗病相关ESTs中的种类与数量最多。数据显示苯丙烷代谢途径、细胞壁结构修饰作用、细胞保卫机制参与了抗病过程。未知功能ESTs与GenBank序列进行BLASTn分析 ,其中许多与病原菌、非病原菌诱导cDNA文库来源的ESTs同源 ;新ESTs占全部ESTs的 16 6 %。
A wheat line, Bai Nong 3217×Mardler BC 5F 4 with resistance to powdery mildew was used in the study. A suppression subtractive hybridization cDNA library was constructed from wheat leaves challenged by Erysiphe graminis DC at primary stage. Seven hundred and sixty ESTs were acquired, and the ESTs similarity analysis based on BLASTx software was finished by comparing sequences in nr database of GenBank. Two hundred and seventy one ESTs'functions were identified in the total ESTs. The results showed that GTP binding proteins associated signal pathway, salicylic acid pathway, MAP pathway etc were supposed to involved in the disease resistance reaction. SAR genes were rich not only in varieties but also in quantity, including five kinds of phyogenesis-related proteins, induced defence-resistance genes, heat shock proteins and genes induced by abiotic-stresses etc. There are lots of evidence to testify PAL pathway, cell wall modification, cell survive system serving in the disease resistance. In the function unknown ESTs,many homologous ESTs were found from other biotic and abiotic-stresses selected cDNA libraries after BLASTn analysis, the stresses included pathogen, salt, drought, cold, high temperature etc.The novel ESTs was 16.6% in total ESTs.
基金
国家重点基础研究发展规划"973"项目
(973 0 8 0 2 )
国家自然科学基金项目 (3 9980 0 2 9)资助~~
