Characterization of IMP-E3, a gene active during imaginal disc morphogenesis in Drosophila melanogaster.
The steroid hormone 20-hydroxyecdysone (20-HE) induces imaginal discs to form adult appendages in Drosophila. We have isolated a set of six ecdysone-responsive genes that apparently encode disc cell-surface or secreted proteins. Transcripts from one of these genes, IMP-E3, accumulate rapidly within 1-2 h in response to hormone. Developmentally, IMP-E3 transcripts reach maximum levels during the first stages of metamorphosis (white prepupae, WPP) and are primarily limited to imaginal tissues. Transcripts are also present during embryogenesis (0-3 h and 12-18 h). Two different-sized transcripts (1.2 and 1.4 kb) result from differential polyadenylation, with the larger transcript predominating in WPP. The conceptual IMP-E3 protein contains a signal peptide, an RGD sequence, and a potential glycosylphosphatidylinositol anchor. We speculate that the protein provides a transient cue important for imaginal disc morphogenesis.
Moore
J T
JT
Department of Molecular and Cell Biology, University of California, Berkeley 94720.
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Hammonds
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D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development; D004441:Ecdysterone / Q000494:pharmacology*; D005786:Gene Expression Regulation; D005796:Genes; D007301:Insect Hormones / Q000235:genetics*; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000235:genetics; D011061:Poly A / Q000378:metabolism; D015183:Restriction Mapping; D014158:Transcription, Genetic
D029721:Drosophila Proteins; C068713:ImpE3 protein, Drosophila; D007301:Insect Hormones; D011061:Poly A; D004441:Ecdysterone