title: A new genetic locus controlling growth and proliferation in Drosophila melanogaster.
abstract: Multicellular organisms grow through both proliferation and growth of their individual cells. We have conducted a P-element-based misexpression screen for genes whose upregulation alters wing disc growth during development. One particular group of four P elements, all inserted at cytological location 61C7-8, exhibited specific overgrowth upon misexpression in proliferating imaginal tissues. Clonal analysis revealed that upon misexpression, cell number was increased but cell size was not affected, indicating that cell growth and proliferation were induced in a coordinate manner. Loss of function at the locus produced small flies with reduced cell number, consistent with the presence of a gene encoding a positive growth regulator. We characterized a new transcription unit initiating in a region adjacent to the P insertions, which generated a complex series of polyadenylated transcripts. Although these RNAs were induced in response to misexpression, none was sufficient by itself to recapitulate overgrowth when overexpressed. This suggested either that a particular combination of these transcripts was necessary or that other sequences are involved.
authors.affiliation: Institute for Signaling, Developmental Biology and Cancer Research, UMR6543 CNRS, Parc Valrose, 06108 Nice Cedex 2, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Raisin
authors.forename: Sophie
authors.initials: S
authors.lastname: Pantalacci
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Breittmayer
authors.forename: Pierre
authors.initials: P
authors.lastname: Léopold
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D001837:Body Weights and Measures; D002455:Cell Division / Q000235:genetics*; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D017931:DNA Primers; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics*; D004625:Embryo, Nonmammalian / Q000196:embryology; D015870:Gene Expression; D018613:Microscopy, Confocal; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D014921:Wings, Animal / Q000196:embryology / Q000254:growth & development*
chemical_list: D017931:DNA Primers