title: Molecular mechanisms of EGF signaling-dependent regulation of pipe, a gene crucial for dorsoventral axis formation in Drosophila.
abstract: During Drosophila oogenesis the expression of the sulfotransferase Pipe in ventral follicle cells is crucial for dorsoventral axis formation. Pipe modifies proteins that are incorporated in the ventral eggshell and activate Toll signaling which in turn initiates embryonic dorsoventral patterning. Ventral pipe expression is the result of an oocyte-derived EGF signal which down-regulates pipe in dorsal follicle cells. The analysis of mutant follicle cell clones reveals that none of the transcription factors known to act downstream of EGF signaling in Drosophila is required or sufficient for pipe regulation. However, the pipe cis-regulatory region harbors a 31-bp element which is essential for pipe repression, and ovarian extracts contain a protein that binds this element. Thus, EGF signaling does not act by down-regulating an activator of pipe as previously suggested but rather by activating a repressor. Surprisingly, this repressor acts independent of the common co-repressors Groucho or CtBP.
authors.affiliation: Institute for Developmental Biology, Biocenter, University of Cologne, Zuelpicher Straße 47b, 50674, Cologne, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Technau
authors.forename: Meike
authors.initials: M
authors.lastname: Knispel
authors.forename: Siegfried
authors.initials: S
authors.lastname: Roth
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D019521:Body Patterning; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins; D015398:Signal Transduction; D015238:Sulfotransferases / Q000235:genetics* / Q000378:metabolism*
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D029721:Drosophila Proteins; D004815:Epidermal Growth Factor; D012097:Repressor Proteins; D015238:Sulfotransferases; C091023:gro protein, Drosophila; C115847:pip protein, Drosophila