Norovirus capsid protein VP1 P-domain (VP1 P-domain)

The Norovirus capsid protein VP1 P-domain is the primary surface-exposed component of the norovirus virion, which is the leading cause of acute viral gastroenteritis globally (CDC, 2023). The VP1 protein is organized into a Shell (S) domain and a Protruding (P) domain, with the latter being further divided into P1 and P2 subdomains (Prasad et al., 1999). The P2 subdomain is the most distal part of the capsid and contains the binding sites for histo-blood group antigens (HBGAs), which serve as essential co-receptors for viral entry into human intestinal cells (Marionneau et al., 2002). As the most immunologically active region, the P-domain is the principal target for neutralizing antibodies elicited by natural infection or vaccination (Lindesmith et al., 2012). Vaccine candidates, such as virus-like particles (VLPs), utilize the P-domain to induce antibodies that block HBGA binding, a correlate of protection against infection (Atmar et al., 2011). However, the P-domain undergoes rapid antigenic drift, particularly in the dominant GII.4 genogroup, necessitating the development of multivalent or broadly reactive vaccines to combat emerging variants (Debbink et al., 2012).

Other names

Major capsid protein VP1Protruding domainP-domainVP1 P-subdomainNorovirus P-domain

Vaccine-induced antibodies bind to the P-domain, specifically the P2 subdomain, to sterically hinder the interaction between the virus and host histo-blood group antigens (HBGAs), thereby neutralizing viral infectivity (Lindesmith et al., 2012; Shanker et al., 2011).