Simian immunodeficiency virus envelope glycoprotein gp120 (SIV gp120)

Simian immunodeficiency virus (SIV) envelope glycoprotein gp120 is the surface subunit of the viral envelope (Env) complex, essential for the infection of host cells [UniProt, https://www.uniprot.org/uniprotkb/P05884/entry]. It is produced by the proteolytic cleavage of the gp160 precursor into gp120 and the transmembrane subunit gp41, which together form trimeric spikes on the virion surface [NIH, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7120343/]. Gp120's primary function is to mediate viral attachment by binding to the host CD4 receptor and a chemokine co-receptor, typically CCR5, which triggers conformational changes in gp41 to initiate membrane fusion [Wikipedia, https://en.wikipedia.org/wiki/Envelope_glycoprotein_GP120]. As the most exposed viral protein, it is the primary target for neutralizing antibodies and a central focus for vaccine and entry inhibitor development [PubMed, https://pubmed.ncbi.nlm.nih.gov/26324120/]. However, gp120 employs sophisticated evasion strategies, including extensive N-linked glycosylation (the glycan shield) and high sequence variability in its five variable loops (V1-V5), which present significant challenges for therapeutic targeting [NIH, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4403475/]. In research models, SIV gp120 serves as a vital surrogate for understanding HIV-1 pathogenesis and testing novel interventions like broadly neutralizing antibodies and attachment inhibitors [Science, https://www.science.org/doi/10.1126/science.aag1619].

Other names

SIV gp120Surface protein gp120SU proteinEnv gp120gp120 subunit of Env

Attachment inhibition, Entry inhibition, Neutralization, Receptor mimicry