DNA-binding specificity of GATA family transcription factors.
GATA-binding proteins constitute a family of transcription factors that recognize a target site conforming to the consensus WGATAR (W = A or T and R = A or G). Here we have used the method of polymerase chain reaction-mediated random site selection to assess in an unbiased manner the DNA-binding specificity of GATA proteins. Contrary to our expectations, we show that GATA proteins bind a variety of motifs that deviate from the previously assigned consensus. Many of the nonconsensus sequences bind protein with high affinity, equivalent to that of conventional GATA motifs. By using the selected sequences as probes in the electrophoretic mobility shift assay, we demonstrate overlapping, but distinct, sequence preferences for GATA family members, specified by their respective DNA-binding domains. Furthermore, we provide additional evidence for interaction of amino and carboxy fingers of GATA-1 in defining its binding site. By performing cotransfection experiments, we also show that transactivation parallels DNA binding. A chimeric protein containing the finger domain of areA and the activation domains of GATA-1 is capable of activating transcription in mammalian cells through GATA motifs. Our findings suggest a mechanism by which GATA proteins might selectively regulate gene expression in cells in which they are coexpressed.
Merika
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Division of Hematology/Oncology, Children's Hospital, Dana-Farber Cancer Institute, Boston, Massachusetts.
Orkin
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SH
D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D050989:GATA2 Transcription Factor; D050990:GATA3 Transcription Factor; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D016335:Zinc Fingers
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; C494688:GATA1 protein, human; D050989:GATA2 Transcription Factor; C494711:GATA2 protein, human; D050990:GATA3 Transcription Factor; C494749:GATA3 protein, human; C494689:Gata1 protein, mouse; C494712:Gata2 protein, mouse; C494748:Gata3 protein, mouse; D015534:Trans-Activators; D014157:Transcription Factors; D004247:DNA