Molecular cloning of cDNA and a chromosomal gene encoding GPE1-BP, a nuclear protein which binds to granulocyte colony-stimulating factor promoter element 1.

Granulocyte colony-stimulating factor (G-CSF) is produced from macrophages in response to lipopolysaccharide (LPS). GPE1, a cis-acting element of the G-CSF gene promoter, functioned as an LPS-inducible element. We isolated cDNA and a chromosomal gene encoding the mouse GPE1-binding protein (GPE1-BP). A 150-amino acid protein deduced from the cDNA has a basic domain and a leucine zipper motif, and seems to be identical to that of recently isolated Ig/EBP. The nuclear extract from COS cells transfected with the cDNA showed GPE1-binding activity. Transcripts were ubiquitously detected, and may be spliced from two exons of a single gene.