Work

Integrated transcriptomic and proteomic analyses of the mechanisms of Citrobacter freundii–induced ‘‘water bubble disease’’ in Macrobrachium rosenbergii

Year: 2026

Type: article

Abstract: The frequent outbreaks of “water bubble disease” in recent years have emerged as a major bottleneck hindering the healthy and sustainable development of the Macrobrachium rosenbergii farming industry. This study aimed to confirm the pathogenicity of Citrobacter freundii in M. rosenbergii through bacterial isolation, identification, challenge tests, and histopathological examination. The median lethal dose was determined to be 1 × 10 4 · 6 CFU/mL. Integrated transcriptomic and proteomic analyses were conducted to further elucidate the molecular mechanisms underlying the dynamic changes in hepatopancreas at 0, 6, and 24 h following C. freundii infection. Progressive tissue damage was observed in the hepatopancreas, including disintegration of the basement membrane and severe cellular vacuolization. The results revealed a distinct temporal pattern in the host defense. At 6 hpi, activation of interleukin-17/nuclear factor κB–mediated inflammatory responses and DNA damage repair pathways was observed, whereas at 24 hpi, enrichment of cytoskeletal remodeling and cardiac muscle contraction pathways was detected, which may be associated with the “water bubble” phenotype. Furthermore, the omics data suggest that C. freundii may employ multilayered immune evasion strategies. At 6 hpi, antigen presentation and lysosomal functions were suppressed, potentially facilitating immune evasion. At 24 hpi, host clearance mechanisms such as phagocytosis, autophagy, and apoptosis were inhibited, coupled with alterations in host energy metabolism, which may support bacterial survival. Transcript–protein correlation analysis further indicated a shift from “decoupling” to “recoupling” in host gene expression regulation over the course of infection. This study provides a multi-omics-based systematic analysis of the molecular changes associated with “water bubble disease” in M. rosenbergii . It offers insights into the potential pathogenesis of C. freundii and provides a foundation for developing targeted control strategies focused on immune-metabolic pathways.

Source: Frontiers in Immunology

DOI: 10.3389/fimmu.2026.1894276