An upstream negative regulatory element in human granulocyte-macrophage colony-stimulating factor promoter is recognised by AP1 family members

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine inv olved in haematopoiesis and host defence. Production of GM-CSF has been det ected in tumour cells including the U87MG astrocytoma cell line. Previous s tudies have been focused on the regulatory role of the proximal region of t he GM-CSF promoter. Our studies on the distal region of the promoter in U87 MG cells identify a negative cis element (-1377/-1298) which contains a AP1 -like site able to bind c-jun and c-fos transcription factors, according to the results of DNA/protein binding assays. Mutagenesis of the AP1-like sit e eliminates AP1 binding and the negative effect on promoter activity. (C) 1998 Federation of European Biochemical Societies.