Abstract: 【Aim】 The peritrophic membrane (PM) is the first natural barrier against the invasion of microbes ingested with foods in insects. This study aims to identify the total protein constituents of the peritrophic membrane of the cotton bollworm, Helicoverpa armigera, a major agricultural insect, so as to lay a foundation for further revealing the formation mechanism of PM and developing novel pest control strategies. 【Methods】 The PMs of the 5th instar larvae of H. armigera were peeled off and then treated with trifluoromethane-sulfonic acid (TFMS). The peritrophic membrane proteome of larvae was identified by liquid chromatography and mass spectrometry (LC-MS/MS), and the identified results were subjected to bioinformatics analysis.【Results】 In this study we identified a total of 169 peritrophic membrane proteins from H. armigera larvae, which is the highest number of PM proteins identified in H. armigera up to date. GO analysis revealed that these identified proteins could be divided into three major categories, i.e., cellular component (CC), molecular function (MF) and biological process (BP). The KEGG enrichment results showed that the identified proteins could be enriched in 12 metabolic pathways. The results of protein-protein interaction (PPI) analysis indicated that ACC and CG3011 proteins could serve as the core proteinprotein interaction network. 【Conclusion】 In this study 169 peritrophic membrane proteins were identified from H. armigera larvae and subjected to GO, KEGG and PPI analyses. The results are helpful to comprehensively understand the molecular structure and function of PM in insects.

Key words: Helicoverpa armigera; peritrophic membrane, proteome, liquid chromatography and mass spectrometry, bioinformatics