title: Isolation and characterization of Urbain, a 20-hydroxyecdysone-inducible gene expressed during morphogenesis of Bombyx mori wing imaginal discs.
abstract: In insects, wing imaginal discs respond to the steroid hormone 20-hydroxyecdysone by initiating morphogenesis leading to the formation of the adult flight appendages. In this work we analyse the expression of a Bombyx gene, referred to as Urbain, whose cDNA had been previously isolated from wing discs (Chareyre et al. 1993). Accumulation of the 1.8 kb transcript occurs concomitantly with the increase of 20-hydroxyecdysone titer at every stage examined during post-embryonic development. In vitro, its accumulation is delayed 6-9 h after exposure to 20-hydroxyecdysone. Studies in the presence of cycloheximide have established that Urbain is a secondary response gene. The sequence of the mRNA contains a putative open reading frame of 1656 nucleotides encoding a secreted hydrophilic protein, and we suggest that the Urbain gene product plays a role in cellular mechanisms involved in morphogenesis of the epithelium.
authors.affiliation: Centre de Génétique Moléculaire et Cellulaire-UMR 106, Université Lyon-1, 43 bd du 11 novembre 1918, F-69622, Villeurbanne Cedex, France.
authors.forename: Marie Thérèse
authors.initials: MT
authors.lastname: Besson
authors.affiliation: Centre de Génétique Moléculaire et Cellulaire-UMR 106, Université Lyon-1, 43 bd du 11 novembre 1918, F-69622, Villeurbanne Cedex, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Chareyre
authors.affiliation: Institut de Biologic et de Chimie des Protéines, 7 passage du Vercors, F-69367, Lyon, Cedex 07, France.
authors.forename: Gilbert
authors.initials: G
authors.lastname: Deléage
authors.affiliation: Centre de Génétique Moléculaire et Cellulaire-UMR 106, Université Lyon-1, 43 bd du 11 novembre 1918, F-69622, Villeurbanne Cedex, France.
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Demont
authors.affiliation: Laboratoire de Zoologie, UA 674, Université de Bourgogne, 6 bd Gabriel, F-21000, Dijon, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Quennedey
authors.affiliation: Laboratoire de Zoologie, UA 674, Université de Bourgogne, 6 bd Gabriel, F-21000, Dijon, France.
authors.forename: Annie
authors.initials: A
authors.lastname: Courrent
authors.affiliation: Centre de Génétique Moléculaire et Cellulaire-UMR 106, Université Lyon-1, 43 bd du 11 novembre 1918, F-69622, Villeurbanne Cedex, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Fourche
authors.affiliation: Centre de Génétique Moléculaire et Cellulaire-UMR 106, Université Lyon-1, 43 bd du 11 novembre 1918, F-69622, Villeurbanne Cedex, France.
authors.forename: Georges
authors.initials: G
authors.lastname: Bosquet
keywords: 20-hydroxyecdysone; Morphogenesis; Wing discs