Rotavirus nonstructural protein 4 (NSP4)

Rotavirus nonstructural protein 4 (NSP4) is an approximately 175 amino acid, multifunctional, endoplasmic reticulum (ER)-localized transmembrane glycoprotein encoded by gene segment 10 of the rotavirus genome[4][5]. NSP4 has diverse roles in the rotavirus life cycle, acting as an intracellular receptor for assembling viral particles, facilitating virus morphogenesis in the ER, and regulating viral transcription[1][3][4]. It is the first described viral enterotoxin and plays a key role in pathogenesis by disrupting host calcium homeostasis, mainly through its viroporin domain, elevating cytosolic calcium and inducing intercellular calcium waves linked to diarrhea severity[4][6][8]. NSP4 also modulates epithelial ion transport (inhibiting sodium absorption and stimulating chloride secretion), disrupts tight junctions and cytoskeletal organization, and is secreted in a form that interacts with cellular integrins (notably α1β1 and α2β1)[4][7]. While not currently a direct therapeutic target, its pivotal role in disease has made it a prominent subject for basic research and a potential target for future anti-rotavirus interventions.

Other names

Rotavirus NSP4Nonstructural glycoprotein NSP4Rotavirus enterotoxinNSP4 protein

Not applicable: No drugs directly targeting NSP4; potential mechanisms (investigational) include inhibition of calcium signaling, blocking enterotoxin-integrin interaction, or interfering with protein function[6][7][8].