       Document 3331
 DOCN  M94A3331
 TI    Functional analysis of HIV-1 glycoproteins with deletions in gp120.
 DT    9412
 AU    Adams O; Schaal H; Scheid A; Universitat Dusseldorf, Germany.
 SO    Int Conf AIDS. 1994 Aug 7-12;10(1):100 (abstract no. PA0020). Unique
       Identifier : AIDSLINE ICA10/94369244
 AB    OBJECTIVES: (1) To determine the contribution of gp120 to the membrane
       fusion activity of the HIV-1 glycoprotein and (2) to determine the
       structured requirements for HIV-1 glycoprotein oligomerization. METHODS:
       A vector was constructed which expresses the HIV-1 env, tat, and rev
       genes under the control of the SV40 early promotor. From this clone two
       vectors were derived expressing a glycoprotein lacking all but the
       C-terminal 10 and 50 amino acid residues of gp120 and two further
       derivatives expressing N-terminal sequences of the rat vasopressin
       precursor protein. Processing of mutant Env-proteins was monitored in
       HeLa T4+ and in COS cells. Fusion activity was monitored after
       transfection in HeLa T4+ cells and transdominant interference was
       measured after co-transfection of a wild-type gp120 vector with the
       deletion- and substitution mutants. RESULTS AND CONCLUSIONS: Mutant
       proteins with gp120 truncations and substitutions were processed in COS
       cells resulting in the formation of gp41. In HeLa T4+ cells, cleavage
       products of truncated env-genes were smaller than gp41 and could not be
       not safely identified with vasopressin hybrid proteins. While
       transfection of HeLa T4+ cells with wild type env vectors results in
       extensive cell-cell fusion, no giant cell formation could be detected
       after transfection with truncated or substituted gp120 mutants. Thus, we
       could not find syncytium formation with gp41 alone. This is in contrast
       to findings with similiar constructs (J. Virol. 66, 4134, 1992).
       Co-transfection of cells with both wt-env vectors and gp120 mutants
       resulted in inhibition of cell-cell fusion indicating that glycoprotein
       oligomerization may occur with mutant glycoproteins lacking most of
       gp120. This effect was more pronounced with vasopressin mutants.
 DE    Animal  Cell Line  Cloning, Molecular  Genetic Vectors  Hela Cells
       Human  HIV Envelope Protein gp120/*GENETICS/*PHYSIOLOGY  HIV Envelope
       Protein gp41/PHYSIOLOGY  HIV-1/*GENETICS/*PHYSIOLOGY  Membrane
       Fusion/GENETICS/PHYSIOLOGY  Protein Processing, Post-Translational  Rats
       Recombinant Fusion Proteins/GENETICS  *Sequence Deletion  Transfection
       Vasopressins/GENETICS  MEETING ABSTRACT

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

