title: Structure of a V3-containing HIV-1 gp120 core.
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.
authors.affiliation: Vaccine Research Center, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA.
authors.forename: Chih-chin
authors.initials: CC
authors.lastname: Huang
authors.forename: Min
authors.initials: M
authors.lastname: Tang
authors.forename: Mei-Yun
authors.initials: MY
authors.lastname: Zhang
authors.forename: Shahzad
authors.initials: S
authors.lastname: Majeed
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Montabana
authors.forename: Robyn L
authors.initials: RL
authors.lastname: Stanfield
authors.forename: Dimiter S
authors.initials: DS
authors.lastname: Dimitrov
authors.forename: Bette
authors.initials: B
authors.lastname: Korber
authors.forename: Joseph
authors.initials: J
authors.lastname: Sodroski
authors.forename: Ian A
authors.initials: IA
authors.lastname: Wilson
authors.forename: Richard
authors.initials: R
authors.lastname: Wyatt
authors.forename: Peter D
authors.initials: PD
authors.lastname: Kwong
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D015704:CD4 Antigens / Q000737:chemistry / Q000378:metabolism*; D003460:Crystallization; D018360:Crystallography, X-Ray; D015483:HIV Antibodies / Q000276:immunology; D015699:HIV Envelope Protein gp120 / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D015497:HIV-1 / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D006801:Humans; D006860:Hydrogen Bonding; D016056:Immunodominant Epitopes; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D019713:Receptors, CCR5 / Q000737:chemistry / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000737:chemistry / Q000378:metabolism
chemical_list: D015704:CD4 Antigens; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D016056:Immunodominant Epitopes; D010446:Peptide Fragments; D019713:Receptors, CCR5; D019718:Receptors, CXCR4