GATA1 (Globin transcription factor 1) is a Cys2/Cys2 zinc finger DNA binding protein that is expressed primarily in erythroid, megakaryocytic, mast cells and eosinophilic cells. It belongs to the GATA family of transcription factors. GATA1 is a transcriptional activator which probably serves as a general switch factor for erythroid development. It binds to DNA sites with the consensus sequence [AT]GATA[AG] within regulatory regions of globin genes and of other genes expressed in erythroid cel