摘要
利用伴刀豆球蛋白（ＣｏｎＡ） 亲和层析、Ｓｅｐｈａｄｅｘ Ｇ＿１５０ 凝胶层析、双向电泳、ＳＤＳ梯度电泳等手段对大丽轮枝菌（Ｖｅｒｔｉｃｉｌｌｉｕｍ ｄａｈｌｉａｅ Ｋｌｅｂ．）分泌的糖蛋白复合物进行分离，对其中一约２６ ｋＤ 的组分进行了Ｎ 端氨基酸序列分析。以棉花（ Ｇｏｓｓｙｐｉｕｍ ｂａｒｂａｄｅｎｓｅ Ｌ．）叶片为材料，进行了糖蛋白致萎性实验。结果表明，沸水浴或ＣｏｎＡ 处理的蛋白致萎性消失，Ｚｅａｔｉｎ 使糖蛋白致萎性减弱。该糖蛋白能够诱导海岛棉培养细胞中棉酚等倍半萜的合成，棉酚的积累随着糖蛋白浓度的增加而增加，但到一定程度后下降。
Verticillium dahliae Kleb. is a phytopathogenic fungus that causes cotton wilt_disease. Glycoproteins secreted by V. dahliae have been found to play an important role in wilting syndrome. In this study the glycoproteins were purified consecutively by ConA_Sepharose 4B affinity chromatography, Sephadex G_150 gel filtration, two_dimensional gel electrophoresis and SDS gradient gel electrophoresis. The N_terminal residual sequence of a 26 kD glycoprotein was analyzed. Plant_wilting tests were carried out by injection of glycoproteins, and those treated by heat, ConA and zeatin, into cotton leaves, respectively. Results showed that heat and ConA treatment abolished the wilt_causing activity of the glycoproteins, and zeatin alleviated the wilt syndrome of cotton. Furthermore, the glycoproteins were found to be effective elicitors in inducing the biosynthesis of sesquiterpene aldehyde phytoalexins in suspension cell cultures of Gossypium barbadense L., and heat_treatment lowered, but not abolished the elicitor activity. However, application of native glycoproteins at the concentration higher than 5 mg/L resulted in cell death.
基金
国家863 计划资助
关键词
棉花
大丽轮枝菌
黄萎病
糖蛋白
Gossypium barbadense, Verticillium dahliae , Wilt, Glycoproteins
