title: The Myb-domain protein ULTRAPETALA1 INTERACTING FACTOR 1 controls floral meristem activities in Arabidopsis.
abstract: Higher plants continuously and iteratively produce new above-ground organs in the form of leaves, stems and flowers. These organs arise from shoot apical meristems whose homeostasis depends on coordination between self-renewal of stem cells and their differentiation into organ founder cells. This coordination is stringently controlled by the central transcription factor WUSCHEL (WUS), which is both necessary and sufficient for stem cell specification in Arabidopsis thaliana ULTRAPETALA1 (ULT1) was previously identified as a plant-specific, negative regulator of WUS expression. However, molecular mechanisms underlying this regulation remain unknown. ULT1 protein contains a SAND putative DNA-binding domain and a B-box, previously proposed as a protein interaction domain in eukaryotes. Here, we characterise a novel partner of ULT1, named ULT1 INTERACTING FACTOR 1 (UIF1), which contains a Myb domain and an EAR motif. UIF1 and ULT1 function in the same pathway for regulation of organ number in the flower. Moreover, UIF1 displays DNA-binding activity and specifically binds to WUS regulatory elements. We thus provide genetic and molecular evidence that UIF1 and ULT1 work together in floral meristem homeostasis, probably by direct repression of WUS expression.
authors.affiliation: Université Grenoble Alpes, Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Grenoble 38054, France CNRS, LPCV, UMR 5168, Grenoble 38054, France CEA, Direction des Sciences du Vivant, BIG, LPCV, Grenoble 38054, France INRA, LPCV, Grenoble 38054, France.
authors.forename: Fanny
authors.initials: F
authors.lastname: Moreau
authors.affiliation: Université Grenoble Alpes, Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Grenoble 38054, France CNRS, LPCV, UMR 5168, Grenoble 38054, France CEA, Direction des Sciences du Vivant, BIG, LPCV, Grenoble 38054, France INRA, LPCV, Grenoble 38054, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Thévenon
authors.affiliation: Université Grenoble Alpes, Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Grenoble 38054, France CNRS, LPCV, UMR 5168, Grenoble 38054, France CEA, Direction des Sciences du Vivant, BIG, LPCV, Grenoble 38054, France INRA, LPCV, Grenoble 38054, France.
authors.forename: Robert
authors.initials: R
authors.lastname: Blanvillain
authors.affiliation: Genomics Unit, Centro Nacional de Biotecnologia CNB- CSIC, Darwin 3, Madrid 28049, Spain.
authors.forename: Irene
authors.initials: I
authors.lastname: Lopez-Vidriero
authors.affiliation: Genomics Unit, Centro Nacional de Biotecnologia CNB- CSIC, Darwin 3, Madrid 28049, Spain.
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: Franco-Zorrilla
authors.affiliation: Université Grenoble Alpes, Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Grenoble 38054, France CNRS, LPCV, UMR 5168, Grenoble 38054, France CEA, Direction des Sciences du Vivant, BIG, LPCV, Grenoble 38054, France INRA, LPCV, Grenoble 38054, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: Dumas
authors.affiliation: Université Grenoble Alpes, Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Grenoble 38054, France CNRS, LPCV, UMR 5168, Grenoble 38054, France CEA, Direction des Sciences du Vivant, BIG, LPCV, Grenoble 38054, France INRA, LPCV, Grenoble 38054, France.
authors.forename: François
authors.initials: F
authors.lastname: Parcy
authors.affiliation: Laboratoire de Reproduction et Développement des Plantes, Université Lyon1, CNRS, INRA, ENS, Lyon cedex 07 69347, France.
authors.forename: Patrice
authors.initials: P
authors.lastname: Morel
authors.affiliation: Laboratoire de Reproduction et Développement des Plantes, Université Lyon1, CNRS, INRA, ENS, Lyon cedex 07 69347, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Trehin
authors.affiliation: Université Grenoble Alpes, Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Grenoble 38054, France CNRS, LPCV, UMR 5168, Grenoble 38054, France CEA, Direction des Sciences du Vivant, BIG, LPCV, Grenoble 38054, France INRA, LPCV, Grenoble 38054, France Christel.carles@ujf-grenoble.fr.
authors.forename: Cristel C
authors.initials: CC
authors.lastname: Carles
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D035264:Flowers / Q000254:growth & development; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000378:metabolism*; D018519:Meristem / Q000254:growth & development*; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000502:physiology*; D018515:Plant Leaves / Q000254:growth & development; D018547:Plant Stems / Q000254:growth & development; D054730:Protein Interaction Domains and Motifs; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D013234:Stem Cells / Q000166:cytology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors; C000610206:UIF1 protein, Arabidopsis; C500130:At4g28190 protein, Arabidopsis; C116421:WUSCHEL protein, Arabidopsis
keywords: Arabidopsis thaliana; Flower; Myb transcription factor; Repressor; Stem cell; WUSCHEL