HIV-1 envelope glycoprotein gp120 (gp120)

The HIV-1 envelope glycoprotein gp120 is a critical surface subunit of the human immunodeficiency virus type 1 (HIV-1) envelope (Env) trimer, essential for viral entry into host cells (UniProt P04578) [1]. Its primary biological function involves a two-step binding process: first, it attaches to the host cell CD4 receptor, which induces a major conformational change in the protein (PubMed: 9634239) [2]. This structural rearrangement exposes the co-receptor binding site, typically the V3 loop, which then interacts with either the CCR5 or CXCR4 chemokine receptors on the host cell surface (NIH/NIAID) [3]. This interaction triggers further changes in the transmembrane subunit gp41, leading to membrane fusion and the release of the viral capsid into the cytoplasm. In the context of disease, gp120 is the primary driver of HIV-1 infection and the subsequent development of AIDS. Therapeutic strategies targeting gp120 include attachment inhibitors like fostemsavir, which binds directly to gp120 to lock it in an 'open' or 'closed' state that prevents CD4 binding (FDA: Rukobia Label) [4]. Additionally, broadly neutralizing antibodies (bnAbs) are being developed to target conserved regions of gp120 to provide long-acting protection and treatment.

Other names

gp120HIV-1 surface glycoproteinEnvelope surface subunit gp120SUEnv

Attachment inhibition by binding to gp120 and preventing the conformational change required for CD4 attachment or co-receptor binding.