VP1, VP2, VP3 and VP4 for the basic unit that forms the icosahedral coat of picornaviruses. Five symmetry-related N termini of coat protein VP4 form a ten-stranded, antiparallel beta barrel around the base of the icosahedral fivefold axis [1].

1: The refined structure of human rhinovirus 16 at 2.15 A resolution: implications for the viral life cycle. Hadfield AT, Lee Wm, Zhao R, Oliveira MA, Minor I, Rueckert RR, Rossmann MG; Structure 1997;5:427-441. PMID:9083115