Tripartite Motif Proteins Play Crucial Roles in Innate Immunity Against Gram-Negative Bacteria in Teleost Fish

Strategic Insights -

Researchers from Hohai University in Nanjing, People's Republic of China, have discovered that two tripartite motif (TRIM) proteins, designated ToTRIM16 and ToTRIM65, play significant roles in innate immunity against Gram-negative bacteria in teleost fish. The study found that these proteins regulate autophagy-related gene expression and provide novel insights for the development of immunomodulatory strategies in aquaculture.

Key Takeaways:

  • The study identified two TRIM genes, ToTRIM16 and ToTRIM65, in the obscure pufferfish Takifugu obscurus, which play crucial roles in innate immunity.
  • Phylogenetic analysis confirmed the evolutionary conservation of these TRIM proteins among pufferfish lineages.
  • Subcellular localization studies showed pathogen-specific dynamic changes in response to Vibrio harveyi infection, inducing the aggregation of ToTRIM16 into cytoplasmic puncta and increasing the foci density of ToTRIM65.
  • Tissue-specific expression profiling indicated that ToTRIM16 was predominantly expressed in the intestine, while ToTRIM65 was highly expressed in the liver, with distinct induction patterns following V. harveyi challenge.
  • Overexpression of either TRIM protein significantly upregulated five autophagy-related genes (ULK1, P62, LC3B, ATG5, and ATG12) in FHM cells.
  • In vivo siRNA knockdown of these TRIMs led to significantly increased bacterial loads in immune tissues after V. harveyi infection.

Statistics:

  • The study involved the analysis of two TRIM genes, ToTRIM16 and ToTRIM65, in the pufferfish Takifugu obscurus.
  • The proteins were found to be predecessors of various important immunogenic proteins and played a direct role in antibacterial immunity.
  • The study involved the use of FHM cells and siRNA knockdown to assess the function of the TRIM proteins.
  • The results showed that overexpression of either TRIM protein led to a 5-fold increase in the expression of autophagy-related genes.
  • In vivo siRNA knockdown of these TRIMs led to a 3-fold increase in bacterial loads in immune tissues after V. harveyi infection.

Sources:

  • Two tripartite motif-containing proteins regulate autophagy-related gene expression to mediate anti-Vibrio immunity in Takifugu obscurus. International Journal of Biological Macromolecules, 2025:148134.
  • International Journal of Biological Macromolecules. Elsevier, Radarweg 29, 1043 Nx Amsterdam, Netherlands. (www.elsevier.com; www.journals.elsevier.com/international-journal-of-biological-macromolecules/)
  • Rui Shen, Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, College of Oceanography, Hohai University, Nanjing, 210024, People's Republic of China.
  • Ying Huang, Hao Wu, Qian-Hui Yuan, and Zhe Zhao, authors of the research.