       Document 0654
 DOCN  M9640654
 TI    Cooperative effects of the human immunodeficiency virus type 1 envelope
       variable loops V1 and V3 in mediating infectivity for T cells.
 DT    9604
 AU    Carrillo A; Ratner L; Department of Medicine, Washington University
       School of Medicine,; St. Louis, Missouri 63110, USA.
 SO    J Virol. 1996 Feb;70(2):1310-6. Unique Identifier : AIDSLINE
       MED/96135256
 AB    Insertion of T-cell line-tropic V3 and V4 loops from the HXB2 strain
       into the macrophage-tropic YU-2 envelope resulted in a virus with
       delayed infectivity for HUT78 and Jurkat cells compared with HXB2.
       Sequence analysis of viral DNA derived from long-term cultures of Jurkat
       cells revealed a specific mutation that changed a highly conserved Asn
       residue in the V1 loop of Env to an Asp residue (N-136-->D).
       Introduction of this mutation into clones containing a T-cell
       line-tropic V3 loop, either with or without a T-cell line-tropic V4
       loop, resulted in viruses that replicated to high levels in Jurkat cells
       and peripheral blood lymphocytes. The Env proteins from these constructs
       were expressed with the vaccinia virus/T7 hybrid system and were found
       to be translated, processed, and cleaved and to bind to soluble CD4
       similar to the wild-type HXB2 and YU-2 Env proteins. Env-mediated fusion
       with HeLa T4+ cells, however, was regulated by both the altered V1 loop
       and T-cell line-tropic V3 loop. These results suggest that subsequent to
       the initial gp120-CD4 binding event, a functional interaction can occur
       between the altered V1 loop and T-cell line-tropic V3 loop that results
       in infection of Jurkat cells and peripheral blood lymphocytes.
 DE    beta-Galactosidase/GENETICS  Amino Acid Sequence  Cloning, Molecular
       Gene Products, env/GENETICS  Human  HIV Envelope Protein
       gp120/*PHYSIOLOGY  HIV-1/*PHYSIOLOGY  Kinetics  Membrane Fusion
       Molecular Sequence Data  Mutation  Peptide Fragments/*PHYSIOLOGY
       Recombinant Fusion Proteins/GENETICS  Support, Non-U.S. Gov't  Support,
       U.S. Gov't, P.H.S.  T-Lymphocytes/*VIROLOGY  Tumor Cells, Cultured
       Vaccinia Virus  JOURNAL ARTICLE

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

