昆虫体内的天然屏障——围食膜

昆虫围食膜是由昆虫中肠上皮细胞分泌的非细胞薄膜状结构,主要成份是几丁质、蛋白质和多糖,是昆虫抵御外界侵害的第一道天然屏障,能够保护中肠上皮细胞不受机械损伤并且能够抵御病毒、细菌及其他有害物质,防止化学损伤.昆虫病毒增效蛋白、荧光增白剂和几丁质酶等生物防治促进因子通过与围食膜上特异位点的结合,能够破坏围食膜结构,加速病原微生物对害虫的感染进程.就围食膜组分、结构、功能以及与害虫防治的关系等方面的研究进展进行综述,并且论述了以围食膜为害虫生物防治靶标的应用前景.

The natural barrier in insects-peritrophic membrane

The peritrophic membrane(PM) of insect is a non-cellular membrane-like structure with uniform thickness,which is secreted by the insect midgut cell and extends from the front of the midgut to the hindgut.The main components of PM are chitin,protein and polysaccharide.PM of insects serves as the first defense line in midgut to resist microorganisms such as viruses,bacteria and other pathogens,and protect the epithelial cells from mechanical damages.Biocontrol-promoting factors,such as baculovirus enhancin,calcofluor and chitinase,can destroy PM′s structure and facilitate infection of pathogens to pest insects by binding with PM components specifically.This paper describes the structure,composition and functions of PM,and reviews the future prospects of new midgut targeting strategies for control of pest insects.