Document 0250
 DOCN  M94A0250
 TI    Conditional regulatory elements of human immunodeficiency virus type 2
       long terminal repeat.
 DT    9412
 AU    Arya SK; Mohr JR; Laboratory of Tumor Cell Biology, National Cancer
       Institute,; National Institutes of Health, Bethesda, Maryland 20892.
 SO    J Gen Virol. 1994 Sep;75 ( Pt 9):2253-60. Unique Identifier : AIDSLINE
       MED/94358723
 AB    Mutational analysis of the human immunodeficiency virus type 2 (HIV-2)
       long terminal repeat (LTR) revealed a novel cis-acting positive and a
       negative regulatory element in the U3 region, located upstream of the
       enhancer-promoter region. These elements acted in a cell type-specific
       manner, being most active in human lymphocytic CEM cells, more active in
       Jurkat cells than in human monocytic U937 cells and least active in
       epithelioid HeLa cells. The down-modulatory effect of the negative
       regulatory element was abolished by HIV-2 Tat, suggesting the
       involvement of upstream DNA elements in optimal Tat-mediated
       trans-activation. The sequence elements that respond to T cell
       activation signals were also located in the upstream U3 region. Notably,
       the magnitude of the effect of the upstream regulatory elements depended
       on the basal activity of the LTR, which was also cell type-dependent.
       This emphasizes the importance of the cell-specific transcriptional
       factors and other effectors in regulating HIV gene expression. These
       observations may be relevant to the cell type-specific restriction of
       virus replication in vivo.
 DE    Base Sequence  Cell Line  Chloramphenicol Acetyltransferase/BIOSYNTHESIS
       Cloning, Molecular  Comparative Study  DNA Mutational Analysis  DNA,
       Viral/CHEMISTRY/GENETICS  Enhancer Elements (Genetics)  Gene Expression
       Hela Cells  Human  *HIV Long Terminal Repeat  HIV-2/*GENETICS
       Lymphocytes  Molecular Sequence Data  Mutagenesis  Promoter Regions
       (Genetics)  Proviruses/GENETICS  *Regulatory Sequences, Nucleic Acid
       Support, U.S. Gov't, P.H.S.  Transfection  JOURNAL ARTICLE

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