Analysis of the 170-kDa lectin gene promoter of Entamoeba histolytica.
The promoter region driving the gene for the 170-kDa heavy subunit of the Entamoeba histolytica galactose-inhibitable lectin was analysed by transient transfection using the chloramphenicol acetyltransferase gene as reporter. S1 mapping confirmed our previous notion that the promoter is located within a 1.35-kb intergenic sequence preceding the structural lectin gene. Transcripts derived from the chloramphenicol acetyltransferase gene of transfected trophozoites were found to be polyadenylated and the transcriptional start mapped to a position similar to that of the wild-type lectin gene. By deletion analysis the entire promoter was restricted to a fragment covering about 550 bp upstream from the start of transcription. On the other hand, residual promoter activity required a sequence of about 140 bp only, encompassing a newly identified CCAAT-box like element around position -100, as well as the amebic specific TATA-box. This 140-bp fragment as well as a stretch of 15 bp, which is located some 100 nt further upstream, were found to be conserved within the 5' noncoding region of a second E. histolytica lectin gene. Point-mutation analyses indicated that the 15-bp fragment, the likely CCAAT-box, as well as the TATA-box are required for full promoter activity.
Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
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H
Buss
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Lioutas
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Dobinsky
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Nickel
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Tannich
D000818:Animals; D001483:Base Sequence; D004748:Entamoeba histolytica / Q000235:genetics*; D017125:Genes, Protozoan; D037102:Lectins / Q000235:genetics*; D008562:Membrane Glycoproteins / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D015800:Protozoan Proteins / Q000235:genetics*; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid
D037102:Lectins; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; C052452:galactose inhibitable adherence protein, Entamoeba histolytica