title: A conformation-specific monoclonal antibody reacting with fusion-active gp41 from the human immunodeficiency virus type 1 envelope glycoprotein.
abstract: The gp41 subunit of the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein plays a major role in the membrane fusion step of viral infection. The ectodomain of gp41 contains a six-helix structural domain that likely represents the core of the fusion-active conformation of the molecule. A monoclonal antibody (MAb), designated NC-1, was generated and cloned from a mouse immunized with the model polypeptide N36(L6)C34, which folds into a stable six-helix bundle. NC-1 binds specifically to both the alpha-helical core domain and the oligomeric forms of gp41. This conformation-dependent reactivity is dramatically reduced by point mutations within the N-terminal coiled-coil region of gp41 which impede formation of the gp41 core. NC-1 binds to the surfaces of HIV-1-infected cells only in the presence of soluble CD4. These results indicate that NC-1 is capable of reacting with fusion-active gp41 in a conformation-specific manner and can be used as a valuable biological reagent for studying the receptor-induced conformational changes in gp41 required for membrane fusion and HIV-1 infection.
authors.affiliation: Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York 10021, USA. sjiang@nybc.org
authors.forename: S
authors.initials: S
authors.lastname: Jiang
authors.forename: K
authors.initials: K
authors.lastname: Lin
authors.forename: M
authors.initials: M
authors.lastname: Lu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D015704:CD4 Antigens / Q000502:physiology; D000939:Epitopes / Q000737:chemistry / Q000235:genetics; D015483:HIV Antibodies; D015700:HIV Envelope Protein gp41 / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D015658:HIV Infections / Q000517:prevention & control; D015497:HIV-1 / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D006801:Humans; D008561:Membrane Fusion / Q000502:physiology; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017433:Protein Structure, Secondary
chemical_list: D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D000939:Epitopes; D015483:HIV Antibodies; D015700:HIV Envelope Protein gp41