title: Role of the gibberellin receptors GID1 during fruit-set in Arabidopsis.
abstract: Gibberellins (GAs) play a critical role in fruit-set and fruit growth. Gibberellin is perceived by its nuclear receptors GA INSENSITIVE DWARF1s (GID1s), which then trigger degradation of downstream repressors DELLAs. To understand the role of the three GA receptor genes (GID1A, GID1B and GID1C) in Arabidopsis during fruit initiation, we have examined their temporal and spatial localization, in combination with analysis of mutant phenotypes. Distinct expression patterns are revealed for each GID1: GID1A is expressed throughout the whole pistil, while GID1B is expressed in ovules, and GID1C is expressed in valves. Functional study of gid1 mutant combinations confirms that GID1A plays a major role during fruit-set and growth, whereas GID1B and GID1C have specific roles in seed development and pod elongation, respectively. Therefore, in ovules, GA perception is mediated by GID1A and GID1B, while GID1A and GID1C are involved in GA perception in valves. To identify tissue-specific interactions between GID1s and DELLAs, we analyzed spatial expression patterns of four DELLA genes that have a role in fruit initiation (GAI, RGA, RGL1 and RGL2). Our data suggest that GID1A can interact with RGA and GAI in all tissues, whereas GID1C-RGL1 and GID1B-RGL2 interactions only occur in valves and ovules, respectively. These results uncover specific functions of each GID1-DELLA in the different GA-dependent processes that occur upon fruit-set. In addition, the distribution of GA receptors in valves along with lack of expression of GA biosynthesis genes in this tissue, strongly suggests transport of GAs from the developing seeds to promote fruit growth.
authors: Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Ingeniero Fausto Elio s/n, 46022 Valencia, Spain.
authors: Carolina
authors: C
authors: Gallego-Giraldo
authors: Department of Biology, Duke University, 124 Science Dr., Durham, NC 27708, USA.
authors: Jianhong
authors: J
authors: Hu
authors: Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Ingeniero Fausto Elio s/n, 46022 Valencia, Spain.
authors: Cristina
authors: C
authors: Urbez
authors: Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Ingeniero Fausto Elio s/n, 46022 Valencia, Spain.
authors: Maria Dolores
authors: MD
authors: Gomez
authors: Department of Biology, Duke University, 124 Science Dr., Durham, NC 27708, USA.
authors: Tai-Ping
authors: TP
authors: Sun
authors: Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Ingeniero Fausto Elio s/n, 46022 Valencia, Spain.
authors: Miguel A
authors: MA
authors: Perez-Amador
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000166:cytology / Q000235:genetics / Q000254:growth & development; D005638:Fruit / Q000166:cytology / Q000235:genetics / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D018525:Germination; D005875:Gibberellins / Q000378:metabolism*; D008954:Models, Biological; D009154:Mutation; D009928:Organ Specificity; D056771:Ovule / Q000166:cytology / Q000235:genetics / Q000254:growth & development; D010641:Phenotype; D010937:Plant Growth Regulators / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D012639:Seeds / Q000166:cytology / Q000235:genetics / Q000254:growth & development
chemical_list: D029681:Arabidopsis Proteins; C109555:GAI protein, Arabidopsis; C512225:GID1a protein, Arabidopsis; C512226:GID1b protein, Arabidopsis; C512227:GID1c protein, Arabidopsis; D005875:Gibberellins; D010937:Plant Growth Regulators; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins
keywords: Arabidopsis; DELLA; GA INSENSITIVE DWARF1; fruit-set; gibberellin