title: Evidence that CRABS CLAW and TOUSLED have conserved their roles in carpel development since the ancestor of the extant angiosperms.
abstract: The carpel is the female reproductive organ specific to flowering plants. We aim to define the genes that controlled carpel development in the common ancestor of this group as a step toward determining the molecular events that were responsible for the evolution of the carpel. CRABS CLAW (CRC) and TOUSLED (TSL) control important aspects of carpel development in the model plant, Arabidopsis thaliana. The basal angiosperm species Amborella trichopoda and Cabomba aquatica very likely represent the two most early diverging groups of flowering plants. We have identified putative orthologues of CRC and TSL from A. trichopoda and C. aquatica, respectively. We demonstrate the expression patterns of these genes in carpels to be very highly conserved, both spatially and temporally, with those of their Arabidopsis orthologues. We argue that CRC and TSL in Arabidopsis are likely to have conserved their respective roles in carpel development since the common ancestor of the living flowering plants. We conclude that a divergent role shown for the CRC orthologue in rice, DROOPING LEAF, most probably arose specifically in the monocot lineage. We show that, in addition to its expression in carpels, the TSL orthologue of C. aquatica is expressed in tissues that contribute to buoyancy and argue that its role in these tissues may have arisen later than its role in carpel development.
authors.affiliation: Laboratoire de Reproduction et Développement des Plantes, Unité Mixte de Recherche 5667, Université Claude Bernard-Lyon, 46 Allée d'Italie, Ecole Normale Supérieure de Lyon, 69364 Lyon Cedex 07, France.
authors.forename: Chloé
authors.initials: C
authors.lastname: Fourquin
authors.forename: Marion
authors.initials: M
authors.lastname: Vinauger-Douard
authors.forename: Bruno
authors.initials: B
authors.lastname: Fogliani
authors.forename: Christian
authors.initials: C
authors.lastname: Dumas
authors.forename: Charles P
authors.initials: CP
authors.lastname: Scutt
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D035264:Flowers / Q000254:growth & development / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D017403:In Situ Hybridization; D019684:Magnoliopsida / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D010802:Phylogeny; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; C119755:CRC protein, Arabidopsis; D018744:DNA, Plant; D012333:RNA, Messenger; D018749:RNA, Plant; D014157:Transcription Factors; C084661:tousled protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases