Article

Structure of a V3-containing HIV-1 gp120 core.

Vaccine Research Center, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA.
Science (Impact Factor: 31.48). 12/2005; 310(5750):1025-8. DOI: 10.1126/science.1118398
Source: PubMed

ABSTRACT The third variable region (V3) of the HIV-1 gp120 envelope glycoprotein is immunodominant and contains features essential for coreceptor binding. We determined the structure of V3 in the context of an HIV-1 gp120 core complexed to the CD4 receptor and to the X5 antibody at 3.5 angstrom resolution. Binding of gp120 to cell-surface CD4 would position V3 so that its coreceptor-binding tip protrudes 30 angstroms from the core toward the target cell membrane. The extended nature and antibody accessibility of V3 explain its immunodominance. Together, the results provide a structural rationale for the role of V3 in HIV entry and neutralization.

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