Poliovirus type 3 capsid protein VP1 (VP1)

The poliovirus type 3 capsid protein VP1 is a major structural component of the viral icosahedral capsid, which consists of 60 copies each of VP1, VP2, VP3, and VP4. VP1 features an eight-stranded antiparallel beta-barrel core decorated with loops and extensions that contribute to the canyon surrounding the fivefold axis on the capsid surface, where the poliovirus receptor (PVR) binds by inserting its domain 1 into this depression.[1][8] This interaction triggers conformational changes leading to the 135S particle intermediate, externalizing the N-terminus of VP1 and VP4 to facilitate membrane insertion and viral RNA release during cell entry.[2][3] The N-terminal extension of VP1, predicted to form an amphipathic helix, associates with host cell membranes, potentially forming a translocation pore for the genome.[2][3] A hydrophobic pocket within VP1's core often contains a "pocket factor" that stabilizes the capsid, and mutations in VP1 loops can alter receptor usage, stability, or drug resistance.[1][3] VP1 plays a critical role in poliovirus pathogenesis by enabling infection of motor neurons, leading to poliomyelitis.[4] Although no small-molecule drugs directly target VP1 clinically, its structure has informed antiviral strategies like pocket-binding compounds in related enteroviruses.[3]

Other names

Poliovirus capsid protein VP1PV VP1