Abstract: 【Aim】 Comparative analysis was performed to investigate differentially expressed proteins between non- and summer-diapausing pupae of the onion fly, Delia antiqua, and to provide a theoretical basis for further exploring the molecular regulation mechanisms of insect diapause and pest control management. 【Methods】 Total proteins were extracted from non-and summer-diapausing pupae, separated by two-dimensional gel electrophoresis, and then analyzed by image analysis. Peptide mass fingerprinting of differential proteins were analyzed by MALDI-TOF MS and identified through database searching in NCBI and SWISS PORT using MASCOT. 【Results】 Proteins were differentially expressed in non- and summer-diapausing pupae. Thirteen differentially expressed proteins were identified by mass spectrometry and bioinformatic analysis, including collagen, SAS6 (spindle assembling abnormal protein 6), MTHFS (5, 10-methenyltetrahydrofolate synthetase), Bnb (bangles and beads) and proteins with unknown functions. 【Conclusion】 The expressions of some proteins are up- or down-regulated in summer-diapausing pupae. Proteins identified in this study may be members of diapause-related protein regulatory networks, and they potentially play important roles in high temperature resistance, chromosome separation, folate metabolism and other physiological processes. 

Key words: Delia antiqua, diapause, total protein, two-dimentional gel electrophoresis, mass spectrographic analysis, bioinformatic analysis