Control of growth and pattering : a novel rol of JAK/STAT in regulating morphogen production and signalling = Control del crecimiento y patrón : un nuevo rol de JAK/STAT regulando la producción y señalización de morfógenos

During my thesis I studied the developmental roles of the JAK/STAT pathway in the wing imaginal disc and we show that it controls organ size and fate specification by regulating morphogen production and activity. We show three distinguishable biological functions of JAK/STAT depending on the territo...

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Detalles Bibliográficos
Autor: Recasens Álvarez, Carles
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2017
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/402782
Acceso en línea:http://hdl.handle.net/10803/402782
Access Level:acceso abierto
Palabra clave:Factors de creixement
Factores de crecimiento
Growth factors
Drosòfila
Drosophila
Transducció de senyal cel·lular
Transducción de la señal celular
Cellular signal transduction
Morfogènesi
Morfogénesis
Morphogenesis
Ciències Experimentals i Matemàtiques
575
Descripción
Sumario:During my thesis I studied the developmental roles of the JAK/STAT pathway in the wing imaginal disc and we show that it controls organ size and fate specification by regulating morphogen production and activity. We show three distinguishable biological functions of JAK/STAT depending on the territory and developmental stage. Briefly, JAK/STAT is required in Drosophila limb development to facilitate the activities of Wingless, Hedgehog and the Dpp morphogens in exerting their fate- and growth-promoting functions. Early in development, JAK/STAT is required to guarantee Wg-mediated appendage specification by repressing EGFR target gene expression and thus restricts the notum fate to the most proximal territories of the wing primordium. Later in development, once the wing has been specified, JAK/STAT regulates organ size by ensuring the stable and localized expression of the Dpp organizer at the center of the wing primordium. This function relies on an autonomous and compartment-specific requirement of JAK/STAT in maintaining the size of the posterior territory. We show that JAK/STAT promotes the cycling and survival of P cells and identified diap1 and CycA as the two critical genes regulated by JAK/STAT and contributing to the growth of the Hh expressing cell population. The specific requirement of the P compartment for JAK/STAT serves to counteract the negative effect of Engrailed on cell cycling and survival. Thus, we identified a mechanism by which pro-survival cues and mitotic cyclins ensure the maintenance of a stable pool of morphogen-producing cells. Finally, we also show that JAK/STAT and its growth-promoting activity in the hinge region function as a topological barrier that isolates the body wall and appendage sources of Dpp to delimit its organizing activity to the developing appendage.