CHARACTERIZATION OF THE PROMOTER FOR THE HUMAN 85 KDA CYTOSOLIC PHOSPHOLIPASE A(2) GENE

The 85 kDa cytosolic phospholipase A(2) (cPLA(2)) plays a key role in the production of arachidonic acid and lysophospholipids, the precurso rs of eicosanoids and platelet-activating factor. Here we report the c loning of the promoter of the human cPLA(2) gene. A 5.7 kb EcoRI fragm ent containing the most 5' region of the cPLA(2) cDNA was sequenced. T he transcription initiation site was identified by rapid amplification of 5'-cDNA ends (5'-RACE) and primer extension analysis. DNA sequence analysis of the 595 base pairs 5' of the transcription start site rev eals a 48 base purine - pyrimidine dinucleotide repeat (CA repeat), fi ve interferon-gamma response elements (gamma-IRE), one interferon-gamm a activated sequence (GAS) and two glucocorticoid response elements (G RE). The promoter lacks a TATA box. It contains a possible CAAT box at - 111 and two octamer binding motifs. The 595 base fragment located i mmediately upstream of the transcriptional start site exhibited functi onal promoter activity in transient transfection assays in a bronchial epithelial cell line (BEAS 2B cells). Deletion analysis revealed that the CA repeat may confer an inhibitory effect on the cPLA(2) promoter activity. The characterization of the human cPLA(2) promoter sequence will allow further studies defining the molecular events regulating t he expression of the cPLA(2) enzyme, especially the cytokine mediated cPLA(2) gene expression.