Human TAF(II)28 and TAF(II)18 interact through a histone fold encoded by atypical evolutionary conserved motifs also found in the SPT3 family.
Determination of the crystal structure of the human TBP-associated factor (hTAF(II))28/hTAF(II)18 heterodimer shows that these TAF(II)s form a novel histone-like pair in the TFIID complex. The histone folds in hTAF(II)28 and hTAF(II)18 were not predicted from their primary sequence, indicating that these TAF(II)s define a novel family of atypical histone fold sequences. The TAF(II)18 and TAF(II)28 histone fold motifs are also present in the N- and C-terminal regions of the SPT3 proteins, suggesting that the histone fold in SPT3 may be reconstituted by intramolecular rather than classical intermolecular interactions. The existence of additional histone-like pairs in both the TFIID and SAGA complexes shows that the histone fold is a more commonly used motif for mediating TAF-TAF interactions than previously believed.
Institut de Génétique et de Biologie, Moléculaire et Cellulaire, CNRS/INSERM/ULP, Illkirch, C.U. de Strasbourg, France.
C
C
Birck
O
O
Poch
C
C
Romier
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M
Ruff
G
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Mengus
A C
AC
Lavigne
I
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Davidson
D
D
Moras
D000595:Amino Acid Sequence; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D004268:DNA-Binding Proteins / Q000737:chemistry*; D019281:Dimerization; D005656:Fungal Proteins / Q000737:chemistry*; D006657:Histones / Q000737:chemistry*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017510:Protein Folding; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D035381:TATA-Binding Protein Associated Factors; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000737:chemistry*; D019473:Transcription Factors, TFII / Q000737:chemistry
D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D006657:Histones; C075582:SPT3 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C113944:TAF11 protein, human; C113945:TAF13 protein, human; D035381:TATA-Binding Protein Associated Factors; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D019473:Transcription Factors, TFII