title: Activation of Rac1 or Cdc42 during early morphogenesis of eye discs induces ectopic antennae in Drosophila.
abstract: The Rho family small guanosine triphosphatases (GTPases) play important roles in many cellular processes, especially in regulation of cytoskeletal organization. In this study, I examined the functions of Rac1 and Cdc42 for disc morphogenesis in Drosophila. I expressed either a constitutively active form or a dominant negative form of each protein during early morphogenesis of eye discs. Inactivation of Rac1 or Cdc42 resulted in small eye phenotypes. On the other hand, I found that activation of either Rac1 or Cdc42 induces ectopic antennae. In some cases, an almost complete antenna was observed instead of an eye, which was possibly transformation from an eye to an antenna. As a molecular evidence for the ectopic antennae, I found that the Distal-less protein, which is essential for the distalization process, was ectopically induced in the eye discs. I also found that the Decapentaplegic and Wingless proteins, which are upstream morphogenetic signaling proteins of the distalization process, could be ectopically induced by activation of Rac1 or Cdc42. My observations suggest novel functions of Rac1 and Cdc42 for disc morphogenesis.
authors.affiliation: Department of Developmental Neurobiology, Kumamoto University Graduate School of Medical Sciences, Honjo 1-1-1, Kumamoto 860-8556, Japan. mj-gou@aist.go.jp
authors.forename: Masahiro J
authors.initials: MJ
authors.lastname: Go
mesh_terms: D000818:Animals; D004330:Drosophila / Q000033:anatomy & histology* / Q000254:growth & development* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D005123:Eye / Q000201:enzymology* / Q000254:growth & development*; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000378:metabolism; D009024:Morphogenesis; D010641:Phenotype; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D051155:Wnt1 Protein; D020744:rac GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C090145:Cdc42 protein, Drosophila; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D011518:Proto-Oncogene Proteins; C090146:Rac1 protein, Drosophila; D014157:Transcription Factors; D051155:Wnt1 Protein; C117261:distal-less protein, insect; C064196:dpp protein, Drosophila; C074622:wg protein, Drosophila; D019204:GTP-Binding Proteins; D020744:rac GTP-Binding Proteins