Nuclear factor recognition sites in the gut-specific enhancer region of an Anopheles gambiae trypsin gene.
The major digestive enzyme of Anopheles gambiae is encoded by the trypsin 1 gene. This gene is expressed exclusively in the gut and its mRNA abundance increases after ingestion of a blood meal. Previous experiments with transgenic Drosophila have shown that the enhancer region, from nucleotide -360 bp to -150 bp upstream of the transcription initiation site, is necessary to drive the gut-specific expression of a reporter gene (Skavdis et al., 1996. EMBO J. 15, 344-350). In this study, we defined DNA sequences within this region that are capable of binding nuclear factors from either gut or non-gut tissues. By electrophoretic mobility shift assays, we determined that a gut-specific nuclear factor recognizes and binds to three sites in the enhancer region with a consensus sequence TYCAAGT. Another factor, found in many tissues, recognizes and binds to at least two additional sites with a consensus sequence ACGATA. This study defines for the first time for an insect gut-specific enhancer, specific sequences that interact with nuclear factors.
Shen
Z
Z
Department of Genetics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4955, USA.
Jacobs-Lorena
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D000818:Animals; D000852:Anopheles / Q000201:enzymology* / Q000235:genetics; D001665:Binding Sites; D004331:Drosophila melanogaster; D004742:Enhancer Elements, Genetic; D005260:Female; D009687:Nuclear Proteins / Q000378:metabolism*; D014357:Trypsin / Q000235:genetics*
D009687:Nuclear Proteins; D014357:Trypsin