       Document 0357
 DOCN  M9460357
 TI    Identification of three N-linked glycans in the V4-V5 region of HIV-1 gp
       120, dispensable for CD4-binding and fusion activity of gp 120.
 DT    9404
 AU    Hemming A; Bolmstedt A; Jansson B; Hansen JE; Travis B; Hu SL; Olofsson
       S; Department of Clinical Virology, University of Goteborg, Sweden.
 SO    Arch Virol. 1994;134(3-4):335-44. Unique Identifier : AIDSLINE
       MED/94175780
 AB    Site-directed mutagenesis was used to study the biological significance
       of three N-linked glycans (linked to Asn406, Asn448, and Asn463),
       situated in the CD4-binding region of gp120. Mutagenesis was carried out
       in a phage M13 system, and the mutated env genes were inserted into
       recombinant vaccinia virus (r-vaccinia virus). To evaluate if the level
       of expression affected the biological phenotype of mutant gp120, we
       expressed the envelope glycoproteins using either a weak (7.5 K) or a
       strong (11 K) promoter of vaccinia virus. The expression of mutated env
       proteins was analyzed after infecting CD4-expressing HeLa cells with the
       r-vaccinia virus, by monitoring the ability of the infected cells to
       generate CD4-dependent syncytia. Env gene products lacking all three
       glycans as well as env gene products lacking different permutations of
       one or two glycans were analyzed. All mutated gp120 species had the
       expected electrophoretical mobility as anticipated from elimination of
       one, two, and three N-linked glycans, respectively. Moreover, all mutant
       env gene products demonstrated the same capacity to induce formation of
       syncytia, irrespective of using the weak or strong promoter for
       expression. These data indicate that the three N-linked glycans studied
       are dispensable for HIV env gene products to function in CD4-binding and
       the subsequent fusion step.
 DE    Amino Acid Sequence  Antigens, CD4/METABOLISM  Cytopathogenic Effect,
       Viral  Electrophoresis, Polyacrylamide Gel  Hela Cells  Human  HIV
       Envelope Protein gp120/*CHEMISTRY/GENETICS  HIV-1/*CHEMISTRY/GENETICS
       Membrane Fusion  Molecular Sequence Data  Mutagenesis
       Polysaccharides/*ANALYSIS  Promoter Regions (Genetics)  Recombinant
       Proteins/CHEMISTRY/GENETICS  Support, Non-U.S. Gov't  Vaccinia
       Virus/GENETICS  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

