Human immunodeficiency virus type 1 envelope glycoprotein gp120–gp41 complex (HIV-1 Env (gp120–gp41))

The human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein complex, commonly designated as Env, comprises a trimer of non-covalently associated gp120 (surface, receptor-binding) and gp41 (transmembrane, fusion-mediating) subunits[1][4][5]. Env is synthesized as a gp160 precursor, cleaved by host proteases into gp120 and gp41, which assemble into a metastable complex on the viral surface[4]. The gp120 subunit binds host CD4 and chemokine receptors (CCR5 or CXCR4), triggering conformational changes that expose and activate gp41, which then mediates the fusion of viral and cellular membranes, allowing viral entry[2][3][4][6]. High conformational flexibility and heavy glycosylation of Env enable immune evasion and complicate vaccine and drug development[1][5][6]. The complex is the principal target of neutralizing antibodies and several entry inhibitors, and remains a critical focus in HIV therapeutic and vaccine research[1][2][6].

Other names

HIV-1 envelope glycoprotein complexHIV-1 gp120–gp41 complexEnvelope glycoprotein (Env)HIV envelope spike

Inhibitors block gp120 interaction with CD4 or coreceptors, preventing conformational changes needed for fusion[6] - Peptide drugs (e.g., Enfuvirtide) bind the gp41 heptad repeat region, blocking six-helix bundle formation and membrane fusion[3] - Neutralizing antibodies prevent gp120–CD4 or gp120–coreceptor binding, or lock Env in a non-fusogenic conformation[4][6]