Transcriptional repression by the Drosophila even-skipped protein: definition of a minimal repression domain.
We have used a transient expression assay employing Drosophila tissue culture cells to study the transcriptional repression activity of the homeo domain protein Even-skipped (Eve). Eve was found to repress all promoters that contained Eve-binding sites, including both TATA-containing and TATA-lacking minimal promoters, as well as promoters activated by several different classes of activator proteins. These findings suggest that the general transcription machinery can be a target of Eve. By analyzing properties of a variety of Eve mutants and chimeric fusion proteins, we have identified several features important for efficient repression. In addition to the DNA-binding domain, a potent repressor requires a repression domain, which can be as small as 27 residues. The minimal 57-residue Eve repression domain, as well as several others studied here, were all found to be proline rich and to contain a high percentage of hydrophobic residues. An intriguing feature of the strong repressors was that their DNA-binding activities, measured by gel retention assays with nuclear extracts, were significantly less than those of derivatives inactive in repression.
Han
K
K
Department of Biological Sciences, Columbia University, New York, New York 10027.
Manley
J L
JL
D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins; D001483:Base Sequence; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D005801:Genes, Homeobox; D018398:Homeodomain Proteins; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D010957:Plasmids; D011392:Proline; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015183:Restriction Mapping; D029701:Saccharomyces cerevisiae Proteins; D016385:TATA Box; D014157:Transcription Factors; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005656:Fungal Proteins; C052130:GAL4 protein, S cerevisiae; D018398:Homeodomain Proteins; D009838:Oligodeoxyribonucleotides; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C052837:eve protein, Drosophila; D011392:Proline; D015500:Chloramphenicol O-Acetyltransferase