Transcriptional regulation of Schistosoma mansoni calreticulin: possible role of AP-1.
Little is known about the regulation and control of Schistosoma mansoni gene expression. In order to study such mechanisms a gene reporter expression vector construction, under the control of a promoter region derived from the S. mansoni calreticulin gene was used to transfect the human Jurkat T cell line. The promoter region contains potential TATA and CAAT boxes as well as an AP-1 core element. We show here that transcriptional factors of eucaryotic cells may induce a gene reporter activity under the control of a S. mansoni promoter region. Treatment of stably transfected cells with N-acetyl cysteine (NAC), a well-characterized antioxidant which counteracts the effects of reactive oxygen intermediates, enhanced the AP-1 dependent transactivation. This effect was abolished when the SmCaR promoter region was deleted in the AP-1 site. Electrophoretic Mobility Shift Assays showed that the AP-1 sequence of S. mansoni bound to both S. mansoni extracts and in nuclear extracts from Jurkat cells, thus explaining possible activation of AP-1 by NAC. Finally treatment of S. mansoni schistosomula and adult worms with NAC induced an increased synthesis of calreticulin protein suggesting a possible role of redox mechanisms in the regulation of a calreticulin gene transcription process in S. mansoni.
Khalife
J
J
Centre d'Immunologie et de Biologie Parasitaire, INSERM U167, Institut Pasteur, Lille, France.
Godin
C
C
Capron
A
A
D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D037282:Calreticulin; D002460:Cell Line; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics; D008969:Molecular Sequence Data; D016877:Oxidants / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012261:Ribonucleoproteins / Q000096:biosynthesis / Q000235:genetics*; D012550:Schistosoma mansoni / Q000235:genetics*; D013601:T-Lymphocytes; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection
D000975:Antioxidants; D002135:Calcium-Binding Proteins; D037282:Calreticulin; D016877:Oxidants; D011993:Recombinant Fusion Proteins; D012261:Ribonucleoproteins; D018808:Transcription Factor AP-1; D008156:Luciferases; D000111:Acetylcysteine