Zinc fingers 1-7 of EVI1 fail to bind to the GATA motif by itself but require the core site GACAAGATA for binding.
EVI1 is a zinc finger oncoprotein that binds via fingers 1-7 to the sequence GACAAGATAA. The target genes on which EVI1 acts are unknown. This binding motif overlaps with that for the GATA transcription factors, (T/A)GATA(A/G), and GATA-1 can bind to and activate transcription via a GACAAGATAA motif. The possibility has been raised that, when overexpressed in leukemogenesis, EVI1 may function by interfering with the differentiation-promoting action of GATA factors. To explore this, we have assessed the affinity of EVI1 for the GATA binding sites derived from erythroid-specific GATA-1 target genes, and found only low affinity interactions. We examined the contacts between EVI1 and DNA by methylation interference studies, which revealed extensive contacts between EVI1 and its binding site. The importance of the contacts for high affinity binding was shown by in vitro quantitative gel shift studies and in vivo cotransfection studies. To examine what types of sequences from mouse genomic DNA bind to EVI1, we isolated and sequenced five EVI1-binding fragments, and each showed the GACAAGATA site. The data presented contribute to our knowledge of the binding specificity of EVI1, and yield a clearer picture of what sequences can, and cannot, act as targets for EVI1 action.
Perkins
A S
AS
Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06520-8023, USA.
Kim
J H
JH
D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D004247:DNA / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D000074008:MDS1 and EVI1 Complex Locus Protein; D008745:Methylation; D051379:Mice; D008969:Molecular Sequence Data; D011519:Proto-Oncogenes; D017421:Sequence Analysis; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D016335:Zinc Fingers / Q000235:genetics*
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; C494689:Gata1 protein, mouse; D000074008:MDS1 and EVI1 Complex Locus Protein; C499305:Mecom protein, mouse; D014157:Transcription Factors; D004247:DNA