FUNCTIONAL-ANALYSIS OF THE SCHISTOSOMA-MANSONI 28 KDA GLUTATHIONE-S-TRANSFERASE GENE PROMOTER - INVOLVEMENT OF SMNF-Y TRANSCRIPTION FACTOR IN MULTIMERIC COMPLEXES
E. Serra et al., FUNCTIONAL-ANALYSIS OF THE SCHISTOSOMA-MANSONI 28 KDA GLUTATHIONE-S-TRANSFERASE GENE PROMOTER - INVOLVEMENT OF SMNF-Y TRANSCRIPTION FACTOR IN MULTIMERIC COMPLEXES, Molecular and biochemical parasitology, 83(1), 1996, pp. 69-80
The ability of the 5' flanking region of the gene encoding the 28 kDa
glutathione S-transferase of Schistosoma mansoni gene to promote trans
cription, was studied in different mammalian cell lines. Results of tr
ansient transfection assays showed a strong activity of the - 277 to 1 nt region of the Sm28GST gene, comparable to that of well-studied p
romoters. Deletion analysis indicated that an AP-1 site and two closel
y located CCAAT (Y1 and Y2) boxes were the principal motifs responsibl
e 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 thre
e Y boxes bound protein complexes from S. mansoni nuclear extracts tha
t 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 promo
ter and data obtained strongly suggested the involvement of SMNF-Y in
multimeric complexes during this process. Copyright (C) 1996 Elsevier
Science B.V.