The silkworm, Bombyx mori Linnaeus, is an important economic insect and a representative model organism of Lepidoptera, which has been widely used in the study of reproduction and development. The development of the silkworm’s reproductive gland is easily affected by many external factors, such as chemical insecticides. After the silkworm larvae were treated with different concentrations of pyriproxyfen, the results showed that the number of eggs and hatching rate of eggs in the silkworm can be reduced by pyriproxyfen, and the concentration effects were displayed. Pyriproxyfen exposure could affect the normal development of the ovary tissue by reducing the number of oocytes and oogonia in the ovaries of silkworm fed with pyriproxyfen. We employed qRT-PCR, to detect the expressions of genes related to ovary development (Vg, Ovo, Otu, Sxl-S and Sxl-L) and hormone regulation (EcR and JHBP2) in silkworm. Our study showed that the transcription levels of Vg, Ovo, Otu, Sxl-S and Sxl-L in the treatment group were lower than those in the control group (6.08%, 61.99%, 83.51%, 99.31% and 71.95%, respectively). The transcription level of ECR was 70.22% for the control group, while that of JHBP2 was upregulated by 3.92-fold. Changes of transcription levels of these genes caused by pyriproxyfen exposure ultimately affect the absorption of nutrients, energy metabolism, ovary development and egg formation of the silkworm, thus leading to reproductive disorders of the silkworm. In general, our study revealed the response of silkworm reproduction to pyriproxyfen exposure and provided a certain reference value for the metabolism of the silkworm to pyriproxyfen.

Bombyx mori nucleopolyhedrovirus (BmNPV) is a silkworm disease that is especially harmful to cocoon production and seriously restricts sericultural development. Our laboratory successfully cultivated a new highly BmNPV-resistant silkworm variety, Huakang 2; however, its mechanism of BmNPV resistance remains unclear. To understand its resistance mechanism, we conducted a metabolomic and transcriptomic study of the midgut of silkworm varieties, Baiyu N and Baiyu after BmNPV infection. We identified 451 differential metabolites, which were mostly comprised of small molecules, such as saccharides, acids, amines, alcohols, and glycosides. We found that the primary differences in disease resistance between the silkworm varieties are metabolic-pathways, tryptophan metabolism, oxidative phosphorylation, ABC-transporters, beta-alanine metabolism, and phenylalanine metabolism. Combined analysis with transcriptomic data suggested that tryptophan metabolism and oxidative phosphorylation are closely related to the silkworms’ BmNPV resistance. We hypothesize that the roles of the two metabolic pathways in the BmNPV resistance mechanism might be the following: Oxidative phosphorylation generates a large amount of adenosine triphosphate (ATP) in response to BmNPV infection to provide silkworms the energy required for establishing BmNPV resistance. Tryptophan metabolism then activates the aryl hydrocarbon receptor (AhR) through the exogenous virus BmNPV, which activates the silkworm’s immune system to defeat BmNPV infections.

Fluoride tolerance is an important economic trait in sericulture, especially in some industrial development regions. Analyses of physiological changes involving structural damage to the insect body and molecular analyses of some related genes have focused on this area; however, the changes that occur at the metabolic level of silkworms after eating fluoride-contaminated mulberry leaves remain unclear. Here, metabonomic analysis was conducted using gas chromatography-mass spectrometry (GC-MS) to analyze the changes in midgut tissue after NaF stress using silkworm strains 733xin (susceptible stain) and T6 (strain resistant to fluoride), which were previously reported by our laboratory. Differential metabolomics analysis showed that both T6 and 733xin strains displayed complex responses after exposure to 200 mg/kg NaF. The purine metabolism and arginine and proline metabolic pathways of fluoride-tolerant strains reached significant levels, among which 3′-adenylic acid and hypoxanthine were significantly upregulated, whereas guanine, allantoic acid, xanthine, N-acetyl-L-glutamic acid, and pyruvate were significantly downregulated. These metabolic pathways may be related to the fluoride tolerance mechanism of NaF poisoning and tolerant strains.

Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the most serious pathogens restricting the sustainable development of the sericulture industry. Currently, there is no effective treatment for BmNPV infection in silkworms, and the mechanism underlying BmNPV resistance in silkworms is also not clear. In this study, comparative transcriptome analyses were carried out in midguts of two silkworm varieties, namely BaiyuN, which is a resistance variety, and Baiyu, which is a susceptible variety, at five different time points (i.e., 0, 1, 3, 6, and 9 h) post-BmNPV infection to detect the early-stage transcriptional changes in these silkworms. In total, 1911 and 1577 differentially expressed genes (DEGs) were identified in the Baiyu and BaiyuN varieties, respectively, involving a total of 48 metabolic pathways. Of these pathways, eight were shared by the Baiyu and BaiyuN varieties in response to BmNPV infection. Notably, four genes (i.e., BGIBMGA08815, BGIBMGA003935, BGIBMGA003571, BGIBMGA010059) were upregulated in the Baiyu variety while downregulated in the BaiyuN variety. The inhibited expression of these four genes in the resistant variety highlighted their potential roles in the resistance of early-stage viral replication. Thus, our study provided a new avenue for the further study of the mechanism underlying BmNPV infection in silkworms and the potential treatment of BmNPV infection.

As a pivotal model organism in Lepidoptera research, the silkworm (Bombyx mori) holds significant importance in life science due to its economic value and biotechnological applications. Advancements in proteomics and bioinformatics have enabled substantial progress in characterizing the B. mori proteome. Systematic screening and identification of protein–protein interactions (PPIs) have progressively elucidated the molecular mechanisms governing key biological processes, including viral infection, immune regulation, and growth development. This review comprehensively summarizes traditional PPI detection techniques, such as yeast two-hybrid (Y2H) and immunoprecipitation (IP), alongside emerging methodologies such as mass spectrometry-based interactomics and artificial intelligence (AI)-driven PPI prediction. We critically analyze the strengths, limitations, and technological integration strategies for each approach, highlighting current field challenges. Furthermore, we elaborate on the molecular regulatory networks of Bombyx mori nucleopolyhedrovirus (BmNPV) from multiple perspectives: apoptosis and cell cycle regulation; viral protein invasion and trafficking; non-coding RNA-mediated modulation; metabolic reprogramming; and host immune evasion. These insights reveal the dynamic interplay between viral replication and host defense mechanisms. Collectively, this synthesis aims to provide a robust theoretical foundation and technical guidance for silkworm genetic improvement, infectious disease management, and the advancement of related biotechnological applications.