Nervous Necrosis Virus capsid protein (NNV CP)

The Nervous Necrosis Virus (NNV) capsid protein is the primary structural component of the Betanodavirus, the causative agent of Viral Encephalopathy and Retinopathy (VER) in over 120 fish species (Nishizawa et al., 1997). Encoded by the RNA2 genomic segment, this protein self-assembles into an icosahedral capsid and is essential for viral attachment and entry into host cells (Bandín & Souto, 2020). As the dominant immunogen, the capsid protein is the central target for the host's humoral immune response, specifically the production of neutralizing antibodies (Costa & Thompson, 2016). Therapeutic interventions primarily involve vaccines, such as DNA vaccines and recombinant subunit vaccines, which utilize the capsid protein to prime the adaptive immune system (Lu et al., 2023). The host's innate immune response to NNV is characterized by the activation of the interferon (IFN) pathway and the subsequent expression of interferon-stimulated genes (ISGs) like Mx and ISG15 (Zou & Secombes, 2011). Challenges in targeting this protein include the high genetic diversity among the four main NNV genotypes (RGNNV, SJNNV, TPNNV, and BFNNV), which can limit the cross-protective efficacy of vaccines (Bandín & Souto, 2020).

Other names

Betanodavirus capsid proteinProtein alphaRNA2-encoded structural proteinNNV structural protein

Induction of neutralizing antibodies that prevent viral adsorption and activation of the host innate antiviral response via the interferon pathway (Costa & Thompson, 2016; Lu et al., 2023).