Advances in research on fish virus receptors.

The specific recognition between a virus and a cell receptor is the initial step of viral invasion, profoundly influencing the virus's host range and pathogenicity, and it is a critical aspect of understanding and controlling viral diseases in fish. This review systematically summarizes the research progress on receptors for major fish RNA viruses and DNA viruses. It reveals the sophisticated strategies viruses have evolved to utilize a variety of host molecules (such as fibronectin, LamR, Nectin, HSP proteins, VDAC2/RACK1, etc.) as receptors. Concurrently, it has been found that different viruses exhibit convergence in their entry mechanisms, such as the common use of heparan sulfate as an initial attachment factor or reliance on clathrin-mediated endocytosis(CME)for internalization. However, this systematic comparison also clearly highlights the current knowledge gaps, namely that the specific protein receptors for several key viruses (PRV, IHNV, VHSV, MSRV, ISKNV, SGIV, CCV) remain unidentified. To address these gaps, clarifying the commonalities and differences in entry mechanisms across various viruses is essential for guiding future research. By reviewing the biological roles of these receptors and the current experimental toolsets, this paper demonstrates that advancing research in this field not only provides a theoretical foundation for revealing viral pathogenesis but also identifies crucial targets for the development of antiviral drugs, novel vaccines, and precise control strategies such as disease-resistant breeding.