棉铃虫唾液凝集素的初步研究

昆虫唾液在成功取食寄主中发挥关键作用.而有关植食性昆虫唾液(反吐液)的研究多集中在与寄主植物的互作关系上,鲜有涉及唾液免疫因子的研究.凝集素作为模式识别受体,在病原物的识别中发挥重要作用,是昆虫重要的免疫因子.棉铃虫幼虫血淋巴中已报道的凝集素种类至少有8种,但其唾液中是否存在凝集素却未见报道.本文通过与鸡血红细胞的血凝...

A preliminary study of lectin in the saliva (regurgitant) of Helicoverpa armigera

Insect saliva plays a major role in successful feeding on host. In recent years, the researches on salivary components of herbivory insects have mainly focused on the co-evolution and relationships between insects and plants, and less attention have been paid to the factors involved in immunity. Lectins, as pattern recognition receptors, play important roles in recognizing foreign substances in the insect immune system. There are at least eight C-type lectins in larval hemolymph of Helicoverpa armigera, but until now no lectin has ever been reported in its saliva (regurgitant). In the present study, the agglutination activity of H. armigera saliva was detected by hemagglutination reaction with chicken erythrocytes. The agglutination reaction of chicken erythrocytes treated with H. armigera saliva was observed obviously under phase contrast microscope. By ammonium sulfate precipitation, the protein precipitated by 35% and 45% ammonium sulfate showed obvious agglutination activity, indicating that the substance with agglutination activity in saliva was a protein. The carbohydrate-inhibition assay discovered the difference between saliva and hemolymph in carbohydrate-binding profiles of lectin, suggesting that they were different lectins. The lectin identified in saliva of H. armigera adds new proof to the understanding of immunity of phytophagous insects.