       Document 0268
 DOCN  M9590268
 TI    Characterisation of p53 responsive regions in the HIV-1 LTR.
 DT    9509
 AU    Tanskanen E; Braithwaite A; Doherty R; Virus Interactions Laboratory,
       Macfarlane Burnet Centre for; Medical Research, Fairfield, Vic.
 SO    Annu Conf Australas Soc HIV Med. 1994 Nov 3-6;6:254 (unnumbered poster).
       Unique Identifier : AIDSLINE ASHM6/95291831
 AB    Transcriptional control over genes of HIV and other retroviruses is
       exerted by regulatory factors via responsive elements in the long
       terminal repeat (LTR). Functional p53 is a nuclear phosphoprotein which
       has a tumour suppressor role in dividing cells. p53 can act as a
       transcription factor, transactivating promoters containing the consensus
       p53 binding site while suppressing some promoters not containing this
       site. We and others have observed that the tumour suppressor protein p53
       is able to repress HIV-1 LTR directed transcription. To characterise the
       regions of the HIV-1 LTR that are responsive to p53 mediated repression
       we have completed a series of transfection experiments with CAT reporter
       constructs containing 18bp sequential deletions of the HIV-1 LTR in the
       presence and absence of over expressed p53. Preliminary results suggest
       that the region containing the TATA box and most 3' SP1 site is
       responsive to repression by p53 and we have also observed that the
       region from nt-147 to nt-93 relative to transcription initiation may
       also be involved. Using in vitro transcribed and translated p53 we have
       been unable to detect direct p53 binding to these regions of the LTR and
       are now investigating the possibility that p53 action is mediated by
       interaction between proteins either in cooperative binding or by acting
       as an inhibitor of transcription factors essential for HIV-1
       transcription.
 DE    Gene Expression Regulation, Viral/PHYSIOLOGY  Human  HIV Long Terminal
       Repeat/*GENETICS  HIV-1/*GENETICS  Protein p53/*GENETICS  Repressor
       Proteins/GENETICS  Transcription, Genetic  Transfection  MEETING
       ABSTRACT

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

