Abstract: The midgut epithelium is the first tissue of silkworm (Bombyx mori) which the virus confronts; larvae resist baculovirus infection by selective apoptosis of infected midgut epithelial cells and by sloughing off infected cells from the midgut before they release virions into the hemocoel. To research the mechanism of nucleopolyhedrovirus resistance of silkworm midgut tissue, we constructed a near-isogenic silkworm line with BmNPV resistance through highly resistant and highly susceptible parent strains. In this study, proteome maps and differences of protein patterns of the midgut tissues of the highly resistant, highly susceptible and near-isogenic silkworm strains were investigated by two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. We compared the proteomic expression of the midgut in these three silkworm strains, and identified five differently expressed proteins. It is inferred that these proteins may be involved in the resistance or susceptibility of BmNPV.

Key words: Bombyx mori, midgut, BmNPV, near-isogenic line, 2-DE, mass spectrometry