title: Multimeric CD4 binding exhibited by human and simian immunodeficiency virus envelope protein dimers.
abstract: The envelope (Env) glycoproteins of human and simian immunodeficiency viruses (HIV and SIV) form noncovalently associated oligomers which mediate virus binding to the cell surface and fusion between the viral envelope and plasma membrane. A high-affinity interaction with CD4 is a critical step in this process. In this report, we show that Env protein dimers, but not monomers, can bind two CD4 molecules simultaneously. Multimeric CD4 binding may have important implications for Env protein-CD4 avidity, CD4-induced release of gp120, and subunit-subunit cooperativity during virus membrane fusion as well as for therapeutic strategies.
authors.affiliation: Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892.
authors.forename: P L
authors.initials: PL
authors.lastname: Earl
authors.forename: R W
authors.initials: RW
authors.lastname: Doms
authors.forename: B
authors.initials: B
authors.lastname: Moss
mesh_terms: D015704:CD4 Antigens / Q000737:chemistry / Q000378:metabolism*; D015686:Gene Products, env / Q000378:metabolism*; D015497:HIV-1 / Q000378:metabolism*; D015302:Simian Immunodeficiency Virus / Q000378:metabolism*
chemical_list: D015704:CD4 Antigens; D015686:Gene Products, env