       Document 0099
 DOCN  M9460099
 TI    A transcriptional regulatory element is associated with a
       nuclease-hypersensitive site in the pol gene of human immunodeficiency
       virus type 1.
 DT    9404
 AU    Van Lint C; Ghysdael J; Paras P Jr; Burny A; Verdin E; Laboratory of
       Viral and Molecular Pathogenesis, National; Institute of Neurological
       Disorders and Stroke, National; Institutes of Health, Bethesda, Maryland
       20892.
 SO    J Virol. 1994 Apr;68(4):2632-48. Unique Identifier : AIDSLINE
       MED/94187105
 AB    Analysis of the chromatin organization of the integrated human
       immunodeficiency virus type 1 (HIV-1) genome has previously revealed a
       major constitutive DNase I-hypersensitive site associated with the pol
       gene (E. Verdin, J. Virol. 65:6790-6799, 1991). In the present report,
       high-resolution mapping of this site with DNase I and micrococcal
       nuclease identified a nucleosome-free region centered around nucleotides
       (nt) 4490 to 4766. A 500-bp fragment encompassing this hypersensitive
       site (nt 4481 to 4982) exhibited transcription-enhancing activity (two-
       to threefold) when it was cloned in its natural position with respect to
       the HIV-1 promoter after transient transfection in U937 and CEM cells.
       Using in vitro footprinting and gel shift assays, we have identified
       four distinct binding sites for nuclear proteins within this positive
       regulatory element. Site B (nt 4519 to 4545) specifically bound four
       distinct nuclear protein complexes: a ubiquitous factor, a
       T-cell-specific factor, a B-cell-specific factor, and the
       monocyte/macrophage- and B-cell-specific transcription factor
       PU.1/Spi-1. In most HIV-1 isolates in which this PU box was not
       conserved, it was replaced by a binding site for the related factor
       Ets1. Factors binding to site C (nt 4681 to 4701) had a DNA-binding
       specificity similar to that of factors binding to site B, except for
       PU.1/Spi-1. A GC box containing a binding site for Sp1 was identified
       (nt 4623 to 4631). Site D (nt 4816 to 4851) specifically bound a
       ubiquitously expressed factor. These results identify a transcriptional
       regulatory element associated with a nuclease-hypersensitive site in the
       pol gene of HIV-1 and suggest that its activity may be controlled by a
       complex interplay of cis-regulatory elements.
 DE    B-Lymphocytes/METABOLISM  Base Sequence  Deoxyribonuclease I/METABOLISM
       DNA, Viral/METABOLISM  Gene Expression Regulation, Viral  *Genes, pol
       Genes, Viral/*GENETICS  Human  HIV Long Terminal Repeat/GENETICS
       HIV-1/*GENETICS  Molecular Sequence Data  Regulatory Sequences, Nucleic
       Acid/*GENETICS  Sequence Homology, Nucleic Acid  Support, Non-U.S. Gov't
       T-Lymphocytes/METABOLISM  Transcription Factor, Sp1/METABOLISM
       Transcription Factors/METABOLISM  *Transcription, Genetic  Virus
       Integration/GENETICS  JOURNAL ARTICLE

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

