Publications & Reports

Characterization of interactions between transcription factors and a regulatory region spanning nt -320 to -281 of the HIV-1 LTR in T-lymphoid and non-T-lymphoid cells.

Pereira LA, Churchill MJ, Elefanty AG, Gouskos T, Lambert PF, Ramsay RG, Deacon NJ
Laboratory for Physiological Chemistry and Centre for Biomedical Genetics, University Medical Centre, Utrecht, The Netherlands.

Abstract

HIV-1 gene expression is regulated by the interplay of transcription factors with multiple binding motifs present within the U3, R and U5 regions of the long terminal repeat (LTR). Here we report novel DNA binding complexes (termed 9a, 9b and 9c) between nuclear proteins from T-lymphoid and non-T-lymphoid cells and a region of the U3 LTR between nucleotides (nts) -320 to -281 in the HIV strain HXB2. Complex 9b bound a motif predicted to bind E-box or c-Myb proteins and a partially overlapping dyad symmetrical motif, and included basic helix-loop-helix proteins (E12, E47 or ITF-1) but surprisingly not c-Myb. Complex 9c, which bound to a pair of GATA sites, included GATA-3 and GATA-4 in Jurkat and MT-2 cells, respectively. We also demonstrate that the c-Myb/E-box and GATA sites form a bipartite motif required for the formation of complex 9a. Transient transfection experiments with T cells revealed that in the context of a minichromosome assembled full-length LTR, mutation of region -320 to -281 increased basal and PMA-stimulated LTR activity. These findings suggest that this region is an important component of the HIV-1 LTR required for response to different cellular transcription factors.

Publication

  • Journal: Journal of Biomedical Science
  • Published: 01/01/2002
  • Volume: 9
  • Issue: 1
  • Pagination: 68-81

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