Identification of two regions from the Drosophila decapentaplegic gene required for embryonic midgut development and larval viability.
The Drosophila decapentaplegic (dpp) gene, a member of the transforming growth factor-beta family, is required for dorsal/ventral pattern formation and midgut and imaginal disk development. We have identified a 3-kb upstream regulatory region necessary for dpp expression in the visceral mesoderm of the gastric caeca primordia and a second 2.5-kb upstream regulatory region necessary for dpp expression in the midgut visceral mesoderm corresponding to a portion of abdominal segments 1 and 2 (parasegment 7). These regulatory regions act over a distance of up to 10-kb on all four of the dpp promoters examined. Absence of dpp expression in the gastric caeca primordia caused defective development of the gastric caeca and a concomitant partial reduction in larval and pupal viability. Absence of dpp expression in the visceral mesoderm of parasegment 7 caused a reduction in the length of the central portion of the larval gut and a change in the morphology of the midgut cells in this region but had little effect on the survival of the animals to the adult stage. However, a larval lethal phenotype was observed when both the central portion of the larval midgut and the gastric caeca were defective.
Masucci
J D
JD
McArdle Laboratory for Cancer Research, University of Wisconsin, Madison 53706.
Hoffmann
F M
FM
D000818:Animals; D004064:Digestive System / Q000196:embryology; D004330:Drosophila; D029721:Drosophila Proteins; D005260:Female; D007301:Insect Hormones / Q000235:genetics*; D007814:Larva / Q000235:genetics; D008297:Male; D009154:Mutation; D010641:Phenotype; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D014158:Transcription, Genetic; D016212:Transforming Growth Factor beta / Q000235:genetics*
D029721:Drosophila Proteins; D007301:Insect Hormones; D016212:Transforming Growth Factor beta; C064196:dpp protein, Drosophila