The resistance of silkworms to Bombyx mori nuclear polyhedrosis virus (BmNPV) is controlled by a major dominant gene and multiple modifying genes. Given the presence of modified genes, it is difficult to determine the main gene by positional cloning. In this study, the main anti-BmNPV gene of BmNPV-resistant silkworm variety N was introduced into the susceptible variety Su to breed the near-isogenic line SuN with BmNPV resistance. The infection process of BmNPV in the hemolymph of Su and SuN was analyzed using the cell analysis system TissueFAXS PLUS. According to the law of infection and proliferation, hemolymph was extracted every 6 h for two-dimensional electrophoresis (2-DE) analysis and quantitative real-time polymerase chain reaction (qRT-PCR). Seven DEPs were found in comparisons between Su and SuN by 2-DE analysis. Among them, acid phosphatase, storage protein, and phenoloxidase can prevent pathogen invasion, which may play a role against BmNPV. Polyamine oxidase plays an important role in energy metabolism, which may be indirectly involved in the process of resisting BmNPV. Most of the transcriptional expression profiles of the seven DEPs were consistent with the 2-DE results. This study can provide a reference for the identification of anti-BmNPV genes and the breeding of BmNPV-resistant silkworm varieties.
Keywords: 2-DE; B. mori; BmNPV; qRT-PCR; resistance gene.