家蚕中肠cDNA T7噬菌体展示文库的构建和免疫相关基因的淘选

中肠是昆虫重要的免疫防御器官之一。为探究家蚕中肠的分子免疫机制,尤其是针对不同病原体的模式识别分子或结合蛋白,以家蚕5龄第3天幼虫中肠为材料,构建家蚕中肠cDNA T7噬菌体展示文库,并分别以几丁质和脂多糖为配体,通过不同方法进行文库的生物淘选。结果共获得10个基因片段,其中在以脂多糖为配体的淘选中获得了β-1,3葡聚糖识别蛋白4,该分子是已知的模式识别受体。另外还获得了多个免疫相关候选基因,如分别编码几丁质结合蛋白、翻译控制的肿瘤蛋白、氨肽酶N、脂肪酰辅酶A结合蛋白等的几个基因。研究结果为深入开展家蚕中肠免疫功能的研究提供了重要线索。

Construction of a T7 Phage Display cDNA Library and Panning for Immune-related Genes from Midgut of Silkworm, Bombyx mori

Midgut is one of the important immune-defense organs for insects.In order to investigate the molecular mechanism of the silkworm’s midgut immune response,especially the interaction of pattern-recognition molecules in midgut with different microbes,a T7 phage display cDNA library of the silkworm’s midgut was constructed by using the midgut of day 3 larvae of the 5th instar.With chitin and lipopolysaccharide as the ligands for biopanning respectively,altogether we obtained 10 protein-coding gene fragments.Among them,panning with lipopolysaccharide as the ligand yielded β-1,3-glucan recognition protein 4 which is a known pattern-recognition receptor.Moreover,some other candidate genes related to immune response were obtained,which encode such proteins as chitin-binding protein,translationally controlled tumor protein,aminopeptidase N,and acyl-CoA binding protein.These results provide important clues for further study on the immune functions of silkworm’s midgut.