Cloning and characterization of human oncostatin M promoter

摘要: Oncostatin M (OSM), an IL-6 subfamily cytokine, inhibits proliferation and causes morphological changes in many tumor cell lines. GM-CSF, phorbol-12-myristate-13-acetate (PMA), lipopolysaccharide (LPS) induce OSM expression. To investigate the mechanisms governing promoter activity, we have cloned partially sequenced 8.5 kb fragment of human genomic DNA immediately 5' coding region mapped transcription start site. Transient transfection assays with a series deletion plasmids demonstrated maximal reporter activity U937 cells minimum 304 bp construct. The 5'-proximal gene contains C/EBP consensus element around -45 several GC-rich regions -60, each which is responsible for basal activity. Electrophoretic mobility shift assay coupled supershift analysis confirmed presence cis -acting binding site activated STAT5 complexes following GM-CSF treatment. Furthermore, transient studies loss responsiveness constructs containing mutations within this STAT element. Our results establish that as yet unidentified factor are while GM-CSF-stimulated expression driven by to on promoter.