title: Response to the dorsal anterior gradient of EGFR signaling in Drosophila oogenesis is prepatterned by earlier posterior EGFR activation.
abstract: Spatially restricted epidermal growth factor receptor (EGFR) activity plays a central role in patterning the follicular epithelium of the Drosophila ovary. In midoogenesis, localized EGFR activation is achieved by the graded dorsal anterior localization of its ligand, Gurken. Graded EGFR activity determines multiple dorsal anterior fates along the dorsal-ventral axis but cannot explain the sharp posterior limit of this domain. Here, we show that posterior follicle cells express the T-box transcription factors Midline and H15, which render cells unable to adopt a dorsal anterior fate in response to EGFR activation. The posterior expression of Midline and H15 is itself induced in early oogenesis by posteriorly localized EGFR signaling, defining a feedback loop in which early induction of Mid and H15 confers a molecular memory that fundamentally alters the outcome of later EGFR signaling. Spatial regulation of the EGFR pathway thus occurs both through localization of the ligand and through localized regulation of the cellular response.
authors: Department of Biology, McGill University, 1205 Doctor Penfield Avenue, Montréal, QC H3A 1B1, Canada.
authors: Mariana
authors: M
authors: Fregoso Lomas
authors: Fiona
authors: F
authors: Hails
authors: Jean-François Boisclair
authors: JF
authors: Lachance
authors: Laura A
authors: LA
authors: Nilson
mesh_terms: D000818:Animals; D019070:Cell Lineage; D004330:Drosophila / Q000378:metabolism* / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism / Q000502:physiology; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D005260:Female; D009154:Mutation; D009866:Oogenesis; D018010:Receptors, Invertebrate Peptide / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D020825:T-Box Domain Proteins / Q000235:genetics / Q000378:metabolism; D016211:Transforming Growth Factor alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; C495572:H15 protein, Drosophila; D018010:Receptors, Invertebrate Peptide; D020825:T-Box Domain Proteins; D016211:Transforming Growth Factor alpha; C083730:grk protein, Drosophila; C495571:mid protein, Drosophila; C066532:Egfr protein, Drosophila; D066246:ErbB Receptors