National Institutes of Health/National Cancer Institute (NIH/NCI)
P30 CA008748
米国
引用
ジャーナル: Nat Commun / 年: 2025 タイトル: CXCR4 mediated recognition of HIV envelope spike and inhibition by CXCL12. 著者: Zhiying Zhang / Hongwei Zhang / Lyuqin Zheng / Shihua Chen / Shuo Du / Junyu Xiao / Dinshaw J Patel / 要旨: CCR5 and CXCR4 both act as HIV co-receptors, though CXCR4 is less explored. CXCR4 binds the chemokine CXCL12 to regulate cellular processes and mediate HIV entry, a process that CXCL12 inhibits. ...CCR5 and CXCR4 both act as HIV co-receptors, though CXCR4 is less explored. CXCR4 binds the chemokine CXCL12 to regulate cellular processes and mediate HIV entry, a process that CXCL12 inhibits. Using cryo-EM, we investigate HIV-2 envelope (Env) spike recognition by CXCR4 and how CXCL12 inhibit this interaction. We discover that CXCR4 unexpected forms a tetramer, both alone and in complex. It binds CXCL12 with 4:8 and 8:8 stoichiometries, with the CXCL12 N-terminus inserting into the CXCR4 pocket. Structures of CXCR4-gp120 complex show one or two gp120 molecules per CXCR4 tetramer, with the V3 loop occupying the major sub-pocket of CXCR4 through deep embedment of its GFKF motif. The CXCL12 N-terminus chashes with gp120 V3 loops, explain its inhibitory effect. Docking analyses of other HIV antagonists further clarify their mechanisms. The CXCR4-gp120 model illustrate how V3 loop residues define co-receptor specificity, offering insights into co-receptor switching and therapeutic design.