       Document 0281
 DOCN  M9590281
 TI    Estrogen response elements of the HIV LTR.
 DT    9509
 AU    Barnes N; Deacon N; Zeichner S; Doherty R; Macfarlane Burnet Centre for
       Medical Research, Fairfield.
 SO    Annu Conf Australas Soc HIV Med. 1994 Nov 3-6;6:241 (unnumbered poster).
       Unique Identifier : AIDSLINE ASHM6/95291818
 AB    We studied a putative estrogen response element (ERE) located in the 5'
       end of the HIV-1 LTR using a panel of 26 linker insertion mutant
       reporter plasmids. Transient transfections of MCF-7 cells grown in
       steroid-free medium were performed using DEAE-dextran Estrogen treated
       cells showed a 2-3 fold increase in CAT activity which could be
       abolished by treatment of cells with the specific estrogen receptor
       antagonist ICI 164,384 (Zenca Pharmacuticals, UK). Linker scanning
       analysis mapped the estrogen response to a 36bp region containing three
       potential ERE half-sites: GGATCAGATATCCACTGACC. Mobility shift assays
       were used to determine DNA binding activity of nuclear proteins from
       cells expressing the estrogen receptor. Oligonucleotides corresponding
       to the 15bp ERE consensus sequence as well as two larger
       oligonucleotides corresponding to the ERE domain of the LTR could bind a
       nuclear protein suggesting further that the estrogen receptor is
       involved in this signalling pathway. Comparison of competitor
       oligonucleotides showed that the nuclear protein binding was strongest
       to the consensus ERE sequence, suggesting that the half site spacing and
       sequences seen in the HIV LTR ERE homolog lead to lowered ability to
       bind the receptor or related proteins. In order to further characterise
       the functional role of each of the three potential half sites, site
       directed mutagenesis of the LTR is in progress.
 DE    Cell Line, Transformed  Estrogens/*PHYSIOLOGY  Gene Expression
       Regulation, Viral/PHYSIOLOGY  Human  HIV Long Terminal Repeat/*GENETICS
       Receptors, Estrogen/GENETICS  Signal Transduction/GENETICS  Transfection
       MEETING ABSTRACT

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

