title: The genital disc of Drosophila melanogaster. : I. Segmental and compartmental organization.
abstract: The genital disc of Drosophila, which gives rise to the genitalia and analia of adult flies, is formed by cells from different embryonic segments. To study the organization of this disc, the expressions of segment polarity and homeotic genes were investigated. The organization of the embryonic genital primordium and the requirement of the engrailed and invected genes in the adult terminalia were also analysed. The results show that the three primordia, the female and male genitalia plus the analia, are composed of an anterior and a posterior compartment. In some aspects, each of the three primordia resemble other discs: the expression of genes such as wingless and decapentaplegic in each anterior compartment is similar to that seen in leg discs, and the absence of engrailed and invected cause duplications of anterior regions, as occurs in wing discs. The absence of lineage restrictions in some regions of the terminalia and the expression of segment polarity genes in the embryonic genital disc suggest that this model of compartmental organization evolves, at least in part, as the disc grows. The expression of homeotic genes suggests a parasegmental organization of the genital disc, although these genes may also change their expression patterns during larval development.
authors.affiliation: Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain, , , , , , ES.
authors.forename: F
authors.initials: F
authors.lastname: Casares
authors.affiliation: Centro de Investigaciones Biológicas, Velazquez 144, 28006 Madrid, Spain, , , , , , ES.
authors.forename: Lucas
authors.initials: L
authors.lastname: Sánchez
authors.affiliation: Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain, , , , , , ES.
authors.forename: Isabel
authors.initials: I
authors.lastname: Guerrero
authors.affiliation: Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain, , , , , , ES.
authors.forename: E
authors.initials: E
authors.lastname: Sánchez-Herrero
keywords: Compartment; Genital disc; Homeotic; Key words Drosophila; engrailed