Deletion Analysis of the Schistosoma mansoni 28 kDa Glutathione S-Transferase Gene Promoter. Functionality of a Proximal AP-1 site

ESTEBAN SERRA; ZEMZOUMI, KHALID; DISSOUS, COLETTE

EUROPEAN JOURNAL OF BIOCHEMISTRY

Wiley

Año: 1997 vol. 248 p. 113 - 119

0014-2956

The 1241-bp promoter region of the Schistosoma mansoni 28-kDa glutathione S-transferase gene (Sm28GST) was sequentially deleted and analyzed using the luciferase reporter gene system in different cell lines. The activator protein-1 (AP-1) site located at -231 seems to be responsible for the major part of the promoter activity. The 1241-bp Sm28GST promoter was not, in transient transfection experiments, activated by reagents generating reactive oxygen species, such as hydrogen peroxide (H2O2), 3-methylcholanthrene, and ter-methylhydroquinone, but was significantly stimulated by phorbol 12-myristate 13-acetate, a potent protein kinase C activator. The involvement of the -231 AP-1 site in phorbol 12-myristate 13-acetate stimulation was demonstrated. Moreover, evidence for in vitro and in vivo binding of the -231 AP-1 site to Jun/Fos dimers was obtained using mobility gel shift assays and co-transfection of embryonic F9 cells with Jun/Fos expression plasmids, respectively. The presence in S. mansoni nuclear extracts of components with affinity for the AP-1 site suggests conservation of this regulatory pathway in the parasite.