Rotavirus VP4 (P genotype) (VP4)

Rotavirus VP4 is the spike-forming outer capsid protein that mediates attachment of the non-enveloped rotavirus virion to host epithelial cell receptors and drives membrane penetration during infectious entry[1][2][5]. It requires cleavage by enteric trypsin-like proteases at conserved arginine residues (R231, R241, R247) to generate VP8* (N-terminal receptor-binding head) and VP5* (C-terminal stalk with membrane interaction domains), enabling conformational changes from an upright to a reversed state that exposes hydrophobic loops for membrane insertion[1][2][3]. VP4 trimers project from the virion surface, anchored by interactions with VP6 and VP7, and undergo protease-dependent rearrangement critical for uncoating and infectivity; mutations like R241T reduce trypsin sensitivity but can be compensated for full replication[1][2]. The P1A serotype corresponds to the P genotype common in human rotaviruses, influencing host tropism via glycan binding (e.g., histo-blood group antigens)[3][7].

Other names

Spike proteinP1A[7]Outer capsid protein VP4Attachment protein VP4