Picornavirus VP1 coat protein (VP1)

The Picornavirus VP1 coat protein is a major structural protein forming part of the icosahedral capsid of all picornaviruses. Sixty copies of VP1, together with VP2, VP3, and (internally) VP4, assemble to protect the viral RNA genome. VP1 localizes predominantly at the five-fold axes of the viral particle and is crucial in forming the "canyon," a depression on the capsid surface that in many picornaviruses serves as the receptor-binding site. During viral entry, VP1 undergoes conformational changes, partially extruding from the capsid to help mediate attachment and penetration of the host cell membrane, ultimately enabling genome release into the cytoplasm. The “jelly-roll” eight-stranded beta-barrel structure of VP1 is highly conserved, but its surface loops are variable, allowing for antigenic diversity and playing a central role in host immune evasion. The VP1 pocket is a binding site for small-molecule antivirals, such as pleconaril, that block viral uncoating. As a principal antigenic determinant, VP1 is both a target for neutralizing antibodies and immune decoy particles and is commonly used for serological detection of multiple picornavirus infections.

Other names

VP1Viral protein 1Capsid protein VP1

Inhibition of uncoating and viral entry by stabilizing the capsid (pleconaril and similar drugs bind to a hydrophobic pocket within VP1, preventing capsid rearrangements required for genome release)