Drosophila 230-kD TFIID subunit, a functional homolog of the human cell cycle gene product, negatively regulates DNA binding of the TATA box-binding subunit of TFIID.
A Drosophila cDNA encoding the largest TFIID subunit (p230) was isolated using a degenerate oligodeoxynucleotide probe based on an amino acid sequence of the purified protein. The entire cDNA sequence contains an open reading frame encoding a polypeptide of 2068 amino acids, corresponding to a calculated molecular mass of 232 kD. The deduced amino acid sequence showed a strong sequence similarity with the protein encoded by a human gene (CCG1) implicated in cell cycle progression through G1, suggesting that p230 may be a target for cell cycle regulatory factors. The recombinant protein expressed in Sf9 cells via a baculovirus vector interacts directly with the TATA box-binding subunit of TFIID (TFIID tau or TBP) from Drosophila, human, and yeast. Surprisingly, recombinant p230 inhibits the TATA box-binding activity and function of TFIID tau, suggesting that p230 interactions with TFIID tau, and possible modulations thereof by other factors may play an important role in TFIID function.
National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892.
T
T
Kokubo
D W
DW
Gong
S
S
Yamashita
M
M
Horikoshi
R G
RG
Roeder
Y
Y
Nakatani
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004330:Drosophila / Q000737:chemistry / Q000196:embryology / Q000235:genetics*; D016193:G1 Phase / Q000235:genetics; D006609:High Mobility Group Proteins / Q000737:chemistry / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D012091:Repetitive Sequences, Nucleic Acid; D017386:Sequence Homology, Amino Acid; D016385:TATA Box; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*
D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; D010446:Peptide Fragments; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D004247:DNA