Human immunodeficiency virus envelope glycoprotein gp120-gp41 complex (HIV Env (or gp120-gp41 complex))

The **human immunodeficiency virus envelope glycoprotein gp120-gp41 complex** comprises two noncovalently associated subunits, gp120 and gp41, generated by proteolytic cleavage of the gp160 precursor polyprotein in the endoplasmic reticulum[1][3][6]. The mature Env complex forms a trimer of gp120-gp41 heterodimers, projecting from the viral surface as a spike[5][6]. Gp120 is responsible for binding to the host cell CD4 receptor and a chemokine coreceptor (CCR5 or CXCR4), initiating conformational changes that enable gp41 to mediate fusion of the viral and cellular membranes[1][3][8]. This complex is essential for HIV entry into susceptible cells, making it a major target for antiviral drugs and neutralizing antibodies. The highly glycosylated structure and conformational flexibility of Env contribute to immune evasion and therapeutic challenges[1][3][6]. Drugs that target Env include attachment inhibitors, fusion inhibitors, and broadly neutralizing antibodies, but rapid mutation and glycan shielding limit the durability of these therapies.

Other names

Envelope glycoprotein gp120Envelope glycoprotein gp160HIV Envgp120gp160

Inhibit attachment of gp120 to CD4 or coreceptors Block conformational changes required for fusion (gp41 targeting) Neutralization by broadly neutralizing antibodies binding gp120 surface epitopes