Functional analysis of the Schistosoma mansoni 28 kDa glutathione S-transferase gene promoter: involvement of SMNF-Y transcription factor in multimeric complexes.
The ability of the 5' flanking region of the gene encoding the 28 kDa glutathione S-transferase of Schistosoma mansoni gene to promote transcription, was studied in different mammalian cell lines. Results of transient transfection assays showed a strong activity of the -277 to +1 nt region of the Sm28GST gene, comparable to that of well-studied promoters. Deletion analysis indicated that an AP-1 site and two closely located CCAAT (Y1 and Y2) boxes were the principal motifs responsible for the promoter activity. Binding of the NF-Y complex to Y1 and Y2, as well as to a third CCAAT box (Y3) close to the promoter TATA box, was compared in gel shift and super-shift experiments. All of the three Y boxes bound protein complexes from S. mansoni nuclear extracts that were shown to contain the A subunit of the schistosome NF-Y complex (SMNF-YA). Competition assays revealed a differential affinity of the Y1, Y2 and Y3 sequences for NF-Y. The Y1, Y2 and Y3 regions were also shown to activate transcription when included in an heterologous promoter and data obtained strongly suggested the involvement of SMNF-Y in multimeric complexes during this process.
Serra
E
E
Unité INSERM 167, Institut Pasteur, Lille, France.
Zemzoumi
K
K
Trolet
J
J
Capron
A
A
Dissous
C
C
D000818:Animals; D001667:Binding, Competitive; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation; D017238:Genes, Helminth; D005982:Glutathione Transferase / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011487:Protein Conformation; D012550:Schistosoma mansoni / Q000201:enzymology / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D014157:Transcription Factors; D005982:Glutathione Transferase