Poliovirus capsid protein complex (VP1–VP4)

The poliovirus capsid protein complex is the viral protein shell that surrounds and protects the single-stranded RNA genome of poliovirus. It consists of 60 copies each of four structural proteins: VP1, VP2, VP3, and VP4, assembled into an icosahedral structure[1][2][3][5]. VP1, VP2, and VP3 form the outer surface, while VP4 is located internally. The capsid surface mediates attachment to the host cellular receptor, poliovirus receptor (PVR/CD155), triggering conformational changes required for cell entry and genome release[1][2][6]. Mutations in the capsid proteins affect viral stability, receptor usage, and susceptibility to antivirals, making the capsid a key therapeutic target in antiviral drug development and vaccine design[4][6]. The complex is not a human protein, but a viral assembly, and serves as a major determinant of viral infectivity and host immune recognition[1][3][5].

Other names

Poliovirus capsidPoliovirus coat proteinsPoliovirus structural proteinsVP1–VP4 proteins

Inhibition of capsid-receptor interaction and uncoating Stabilization of the capsid to prevent conformational change required for viral RNA release