Human immunodeficiency virus type 1 envelope glycoprotein A (HIV-1 Env)

The HIV-1 envelope glycoprotein is a trimeric complex on the viral surface composed of three noncovalently associated heterodimers, each consisting of a surface subunit (gp120) and a transmembrane subunit (gp41)[1][2][3][4][5][6]. The precursor protein, gp160, is cleaved during maturation to generate these functional subunits. gp120 mediates high-affinity binding to the CD4 receptor on target cells and subsequent binding to a chemokine coreceptor (CCR5 or CXCR4), while gp41 promotes fusion of the viral and cellular membranes, allowing entry of the viral genome into the host. The HIV-1 Env spike is the sole viral protein exposed on the surface and is heavily glycosylated, forming a "glycan shield" that helps evade humoral immune responses. Env is the principal target for broadly neutralizing antibodies, fusion inhibitors, and entry inhibitors, and is a major focus for vaccine design and antiviral interventions[1][2][3][5][6][7][9].

Other names

HIV-1 EnvEnvelope glycoprotein gp160gp120 (surface component)gp41 (transmembrane component)

Blockade of receptor or coreceptor binding: Prevents gp120 from attaching to CD4 or CCR5/CXCR4[7] Inhibition of conformational change/fusion: Prevents gp41-mediated fusion of viral and cellular membranes[2][5] Neutralization by antibodies: Binds critical Env sites, blocking function and/or triggering immune clearance[7]