Norwalk virus attachment protein (NORVA) (NORVA)

The Norwalk virus attachment (NORVA) protein is a 105-kDa cellular membrane protein identified as a candidate receptor or attachment factor for Norwalk virus (NV) and other human noroviruses (Tamura et al., 2000). First characterized using virus overlay protein-binding assays (VOPBA), it mediates the specific, dose-dependent attachment of recombinant virus-like particles (VLPs) to the surface of various mammalian cells, including the Caco-2 intestinal cell line (Tamura et al., 2000; White et al., 1996). Unlike the well-known carbohydrate-based histo-blood group antigens (HBGAs), NORVA facilitates binding through direct protein-protein interactions that require the protein's native conformational structure (Tamura et al., 2000; Frontiers in Microbiology, 2017). It is ubiquitously expressed across multiple mammalian cell lines, suggesting a conserved role in the initial stages of norovirus infection and internalization (Tamura et al., 2000). Although its precise molecular identity and gene sequence have remained elusive in early characterizations, NORVA represents a significant target for the development of antiviral strategies aimed at blocking viral entry into host cells (Tamura et al., 2004). Research indicates that its interaction with the viral capsid is distinct from that of heparan sulfate and other known attachment factors (Tamura et al., 2004; Expert Reviews in Molecular Medicine, 2007).

Other names

105-kDa cellular Norwalk VLP-binding proteinNV attachment protein105-kDa cellular binding proteinNorwalk virus attachment protein

Viral attachment inhibition