Direct interaction of human TFIID with the HIV-1 transactivator tat.
The tat gene of the human immunodeficiency virus (HIV) plays a central role in the activation and life cycle of HIV. The tat protein (Tat) specifically transactivates HIV transcription in vivo and in vitro, exerting its effects at the level of transcriptional initiation and elongation. Here we report that Tat binds directly to the basal transcription factor TFIID. The transcriptional activity of HeLa extracts was depleted after chromatography on a Tat affinity column, which specifically retained the polymerase II-specific factor TFIID. Direct interaction of Tat with holo-TFIID, composed of TATA-binding protein (TBP) and associated factors (TAFs), was observed. Tat binds, through amino acids 36-50, directly to the TBP subunit of TFIID. Our results suggest that Tat may transduce upstream or downstream regulatory signals by direct interaction with the basal transcription factor TFIID.
Kashanchi
F
F
Laboratory of Molecular Virology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892.
Piras
G
G
Radonovich
M F
MF
Duvall
J F
JF
Fattaey
A
A
Chiang
C M
CM
Roeder
R G
RG
Brady
J N
JN
D001483:Base Sequence; D004279:DNA, Viral; D004268:DNA-Binding Proteins / Q000378:metabolism; D015696:Gene Products, tat / Q000235:genetics / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D015497:HIV-1 / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D054322:tat Gene Products, Human Immunodeficiency Virus
D004279:DNA, Viral; D004268:DNA-Binding Proteins; D015696:Gene Products, tat; D011993:Recombinant Fusion Proteins; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D054322:tat Gene Products, Human Immunodeficiency Virus; D005982:Glutathione Transferase