Document 0497
 DOCN  M9550497
 TI    HTLV-1 Tax enhances NF-kappa B2 expression and binds to the products p52
       and p100, but does not suppress the inhibitory function of p100.
 DT    9505
 AU    Murakami T; Hirai H; Suzuki T; Fujisawa J; Yoshida M; Department of
       Cellular and Molecular Biology, University of; Tokyo, Japan.
 SO    Virology. 1995 Feb 1;206(2):1066-74. Unique Identifier : AIDSLINE
       MED/95159418
 AB    Tax protein of HTLV-1 triggers transcriptional activation through
       enhancers, NF-kappa B binding site, 21-bp enhancer, and serum response
       element. Previously, we demonstrated binding of Tax to transcription
       factors NF-kappa B1 p105 and p50. Here, we report that Tax enhances
       expression of NF-kappa B2 at the mRNA level and proteins; the effect was
       more apparent on the p52 expression than on its precursor p100,
       suggesting post-translational regulation. Consistent with these
       observations, HTLV-1-infected T-cell lines expressed higher levels of
       p52. Tax binds to the protein products p52 and p100 which inhibits
       NF-kappa B proteins forming cytoplasmic complexes; the binding to p100
       was preferential over NF-kappa B1 p105. However, Tax did not induce
       efficient dissociation of the cytoplasmic complexes p100/c-Rel or
       p100/p65, and thus did not induce nuclear translocation of c-Rel or p65.
       This was in sharp contrast to the previous observation that Tax
       dissociated the p105/c-Rel and I kappa B-gamma/p65 complexes. These
       results indicate that HTLV-1 Tax interacts with NF-kappa B2 p100 and p52
       and upregulate the NF-kappa B function, but their contribution to
       Tax-mediated transcriptional regulation differs from those of NF-kappa
       B1.
 DE    Base Sequence  Binding Sites  Cell Line  Cell Line, Transformed  Cell
       Nucleus/METABOLISM  Enhancer Elements (Genetics)  Gene Expression
       Regulation  Gene Products, tax/BIOSYNTHESIS/*METABOLISM  Hela Cells
       Human  HTLV-I/GENETICS/*METABOLISM  Kidney  Macromolecular Systems
       Molecular Sequence Data  NF-kappa B/*BIOSYNTHESIS  Polymerase Chain
       Reaction  Promoter Regions (Genetics)  Protein Binding  Proto-Oncogene
       Proteins/BIOSYNTHESIS  Support, Non-U.S. Gov't  T-Lymphocytes
       Transcription, Genetic  Transfection  Tumor Cells, Cultured  JOURNAL
       ARTICLE

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