title: Down-regulation of a single auxin efflux transport protein in tomato induces precocious fruit development.
abstract: The PIN-FORMED (PIN) auxin efflux transport protein family has been well characterized in the model plant Arabidopsis thaliana, where these proteins are crucial for auxin regulation of various aspects of plant development. Recent evidence indicates that PIN proteins may play a role in fruit set and early fruit development in tomato (Solanum lycopersicum), but functional analyses of PIN-silenced plants failed to corroborate this hypothesis. Here it is demonstrated that silencing specifically the tomato SlPIN4 gene, which is predominantly expressed in tomato flower bud and young developing fruit, leads to parthenocarpic fruits due to precocious fruit development before fertilization. This phenotype was associated with only slight modifications of auxin homeostasis at early stages of flower bud development and with minor alterations of ARF and Aux/IAA gene expression. However, microarray transcriptome analysis and large-scale quantitative RT-PCR profiling of transcription factors in developing flower bud and fruit highlighted differentially expressed regulatory genes, which are potential targets for auxin control of fruit set and development in tomato. In conclusion, this work provides clear evidence that the tomato PIN protein SlPIN4 plays a major role in auxin regulation of tomato fruit set, possibly by preventing precocious fruit development in the absence of pollination, and further gives new insights into the target genes involved in fruit set.
authors: INRA, UMR 1332 de Biologie du fruit et Pathologie, F-33140 Villenave d'Ornon, France.
authors: Fabien
authors: F
authors: Mounet
authors: Annick
authors: A
authors: Moing
authors: Mariusz
authors: M
authors: Kowalczyk
authors: Johannes
authors: J
authors: Rohrmann
authors: Johann
authors: J
authors: Petit
authors: Virginie
authors: V
authors: Garcia
authors: Mickaël
authors: M
authors: Maucourt
authors: Kentaro
authors: K
authors: Yano
authors: Catherine
authors: C
authors: Deborde
authors: Koh
authors: K
authors: Aoki
authors: Hélène
authors: H
authors: Bergès
authors: Antonio
authors: A
authors: Granell
authors: Alisdair R
authors: AR
authors: Fernie
authors: Catherine
authors: C
authors: Bellini
authors: Christophe
authors: C
authors: Rothan
authors: Martine
authors: M
authors: Lemaire-Chamley
mesh_terms: D001692:Biological Transport; D015536:Down-Regulation; D035264:Flowers; D005638:Fruit / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000166:cytology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots; D030821:Plants, Genetically Modified; D034622:RNA Interference; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins; D014157:Transcription Factors