Expression of GATA-binding transcription factors in rat hepatocytes.

Recently, we demonstrated that a DNA-binding protein(s) is involved in transcriptional repression of the rat serine dehydratase gene in fetal liver. Here, we report that a GAT(A/T) motif is the target sequence for the DNA-binding protein. By screening a fetal liver cDNA library, we isolated a rat homolog of GATA-1. Rat GATA-1 expressed as a GST-fusion protein in E. coli bound to the GAT(A/T) motif in the serine dehydratase gene. Northern analysis show that GATA-1 and GATA-4 mRNAs are expressed in fetal hepatocytes.