Functional characterization of a complex protein-DNA-binding domain located within the human immunodeficiency virus type 1 long terminal repeat leader region.
Transcriptional trans activation of the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) by the viral tat trans activator is mediated by an LTR-specific sequence located immediately 3' to the start of transcription initiation. We have used a range of molecular techniques to examine DNA-protein interactions that occur in the vicinity of this cis-acting sequence. Our results demonstrate the existence of a sequence-specific DNA-protein interaction involving the HIV-1 leader DNA and map this binding event to between -2 and +21 base pairs relative to the HIV-1 LTR transcription start site. Evidence suggesting that this interaction involves three distinct protein-DNA contact sites extending along one side of the DNA helix is presented. Mutation of these sites was found to ablate protein-DNA binding yet was observed to have no effect on either the basal or tat trans-activated level of HIV-1 LTR-specific gene expression. We therefore conclude that this DNA-protein interaction has a function distinct from the regulation of HIV-1 LTR-specific gene expression.
Malim
M H
MH
Howard Hughes Medical Institute, Duke University Medical Center, Durham, North Carolina 27710.
Fenrick
R
R
Ballard
D W
DW
Hauber
J
J
Böhnlein
E
E
Cullen
B R
BR
D001483:Base Sequence; D002460:Cell Line; D015342:DNA Probes; D004279:DNA, Viral / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D015696:Gene Products, tat; D015497:HIV-1 / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D008745:Methylation; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D021382:Protein Sorting Signals / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics; D014158:Transcription, Genetic; D014162:Transfection; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D054322:tat Gene Products, Human Immunodeficiency Virus
D015342:DNA Probes; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D015696:Gene Products, tat; D021382:Protein Sorting Signals; D014157:Transcription Factors; D014764:Viral Proteins; D054322:tat Gene Products, Human Immunodeficiency Virus