Envelope glycoprotein gp120 of Human Immunodeficiency Virus (gp120)

Envelope glycoprotein gp120 is a ~120 kDa heavily glycosylated viral protein exposed on the surface of HIV. It is produced via cleavage from a larger precursor, gp160, and forms a noncovalent trimeric complex with gp41 in the viral envelope. During infection, gp120 binds with high affinity to the CD4 receptor, mainly on helper T cells, and then to a chemokine coreceptor (CCR5 or CXCR4), initiating conformational changes that result in fusion of the viral and host cell membranes. Its complex structure features inner and outer domains and extensive variable loops, which confer immune evasion abilities by shielding conserved receptor-binding sites with glycans. These structural and functional properties make gp120 a primary target for therapeutic drugs and vaccines[1][2][3][4][5].

Other names

gp120HIV envelope glycoprotein gp120SU (Surface Unit, in context with SU/TM designation[3])HIV-1 gp120

Drugs/antibodies block gp120 binding to host cell receptors or induce conformational changes preventing fusion[1][5] Small molecules (e.g., fostemsavir) bind gp120 and prevent attachment to CD4 Antibodies bind conserved regions of gp120 to neutralize virus