National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)
R01 AI145687
米国
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)
U54 AI170752
米国
引用
ジャーナル: Nat Commun / 年: 2025 タイトル: Conformational trajectory of the HIV-1 fusion peptide during CD4-induced envelope opening. 著者: Bhishem Thakur / Revansiddha H Katte / Wang Xu / Katarzyna Janowska / Salam Sammour / Rory Henderson / Maolin Lu / Peter D Kwong / Priyamvada Acharya / 要旨: 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 ...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 substantial receptor-induced Env opening. We delineate stepwise Env opening from its closed state to a functional CD4-bound symmetrically open Env in which we show that FP was accessible for antibody binding. We define downstream re-organizations that lead to the formation of a gp120/gp41 cavity into which the FP buries to become inaccessible for antibody binding. These findings improve our understanding of HIV-1 entry and delineate the entry-related conformational trajectory of a key site of HIV vulnerability to neutralizing antibody.