Adf-1 is a nonmodular transcription factor that contains a TAF-binding Myb-like motif.
Adf-1 is an essential Drosophila melanogaster sequence-specific transactivator that binds the promoters of a diverse group of genes. We have performed a comprehensive mapping of the functional domains of Adf-1 to study the role of transactivators in the process of gene activation. Using a series of clustered point mutations and small deletions we have identified regions of Adf-1 required for DNA binding, dimerization, and activation. In contrast to most enhancer-binding factors, the Adf-1 activation regions are nonmodular and depend on an intact protein, including the Adf-1 DNA-binding domain, for activity. Like many transcriptional activators, Adf-1 contains a TFIID-binding domain that can interact with specific TAF subunits. Although TAFs are required for Adf-1-directed activation, TAF binding is not sufficient, suggesting that Adf-1 may direct multiple essential steps during activation. Interestingly, both the TAF-binding domain and the DNA-binding domain contain sequences homologous to those of the Myb family of DNA-binding domains. Thus, Adf-1 has evolved an unusual structure containing two versions of the Myb motif, one that binds DNA and one that binds proteins.
Cutler
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G
Howard Hughes Medical Institute, University of California, Berkeley 94720, USA.
Perry
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KM
Tjian
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D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D019281:Dimerization; D004330:Drosophila; D029721:Drosophila Proteins; D005656:Fungal Proteins / Q000737:chemistry; D051548:Histone Acetyltransferases; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009687:Nuclear Proteins / Q000378:metabolism*; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000737:chemistry*; D020598:Proto-Oncogene Proteins c-myb; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D035381:TATA-Binding Protein Associated Factors; D035181:TATA-Box Binding Protein; D015534:Trans-Activators / Q000737:chemistry*; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation
C090575:ADA2 protein, S cerevisiae; C072263:Adf1 protein, Drosophila; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005656:Fungal Proteins; D019476:Insect Proteins; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D020598:Proto-Oncogene Proteins c-myb; D029701:Saccharomyces cerevisiae Proteins; D035381:TATA-Binding Protein Associated Factors; D035181:TATA-Box Binding Protein; C103338:Taf4 protein, Drosophila; D015534:Trans-Activators; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D004247:DNA; D051548:Histone Acetyltransferases; C069001:TATA-binding protein associated factor 250 kDa