Purification and characterization of multiple nuclear factors that bind to the TAX-inducible enhancer within the human T-cell leukemia virus type 1 long terminal repeat.
Within the human T-cell leukemia virus type I promoter, there are three copies of a 21-base-pair repeat (hereafter called the tax-responsive element [TRE]) that both contributes to basal promoter activity and mediates induction by the viral activator TAX. We have identified and separated three nuclear proteins that interact with the TRE. The TRE-binding protein designated TREB-3 bound more avidly to a multimerized TRE than to a single-copy TRE, while the other two TRE-binding proteins, TREB-1 and TREB-2, bound equally well to either TRE. TREB-1 has been purified to near homogeneity, and binding activity was localized to a protein of 35 to 43 kilodaltons. The affinity-purified TREB-1 activated transcription from the human T-cell leukemia virus type I promoter in vitro. The purified TREB-1 fraction contained activating transcription factor binding activity and showed a cooperative interaction with the TATA-binding factor (TFIID) on the adenovirus E4 promoter.
Tan
T H
TH
Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021.
Horikoshi
M
M
Roeder
R G
RG
D001483:Base Sequence; D001665:Binding Sites; D002461:Cell Line, Transformed; D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D015486:HTLV-I Antigens / Q000302:isolation & purification / Q000378:metabolism*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D015534:Trans-Activators; D014157:Transcription Factors / Q000302:isolation & purification / Q000378:metabolism*
D004279:DNA, Viral; D004268:DNA-Binding Proteins; D015486:HTLV-I Antigens; D015534:Trans-Activators; D014157:Transcription Factors