Conformational trajectory of the HIV-1 fusion peptide during CD4-induced envelope opening.

ABSTRACT: The hydrophobic fusion peptide (FP), a critical component of the HIV-1 entry machinery, is located at the N terminus of the envelope (Env) gp41 subunit. The receptor-binding gp120 subunit of Env forms a heterodimer with gp41. The gp120/gp41 heterodimer assembles into a homotrimer, in which FP is accessible for antibody binding. Env conformational changes or "opening" that follow receptor binding result in FP relocating to a newly formed interprotomer pocket at the gp41-gp120 interface where it is sterically inaccessible to antibodies. The mechanistic steps connecting the entry-related transition of antibody accessible-to-inaccessible FP configurations remain unresolved. Here, using SOSIP-stabilized Env ectodomains, we visualize that the FP remains accessible for antibody binding despite su

SUBMITTER: Thakur B 

PROVIDER: S-EPMC12085566 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature