HUMAN 15-LIPOXYGENASE GENE PROMOTER - ANALYSIS AND IDENTIFICATION OF DNA-BINDING SITES FOR IL-13-INDUCED REGULATORY FACTORS IN MONOCYTES

In order to study the transcriptional control of 15-LO expression, we have cloned and sequenced the human 15-LO promoter region. The 15-LO p romoter is associated with a CpG island at the 5'-end of the gene, and sequence analysis reveals putative Spl and Ap2 binding site/s and abs ence of TATA or CAAT motifs. Transcription is initiated at one major s ite. Using deletion constructs, we have defined an active promoter reg ion of 1056 bp. Gel-shift assays revealed that transcriptional factor( s) induced only in response to IL-13 treatment of human peripheral blo od monocytes bind to the 15-LO promoter DNA. Two regions, DP1 (-140 to -92 bp) and DP2 (-353 to -304 bp) of the promoter were essential for transcription in HeLa cells and human peripheral monocytes. Hela nucle ar extracts contained a specific nuclear factor(s) binding to 15-LO pr omoter DNA which are distinct from those derived from IL-13-treated hu man peripheral monocyte nuclear extracts. In addition, fluorescent in situ hybridization (FISH) results refined the previous localization of 15-LO to human chromosome 17p13.3.