Journal Article

INDEHISCENT and SPATULA interact to specify carpel and valve margin tissue and thus promote seed dispersal in Arabidopsis

School of Biological Sciences ; University of East Anglia [Norwich] (UEA), Reproduction et développement des plantes (RDP) ; École normale supérieure de Lyon (ENS de Lyon) ; Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Centre National de la Recherche Scientifique (CNRS), O'Brien, Martin, Körner, Evelyn, Fuentes, Sara, Department of Crop Genetics [Norwich] ; John Innes Centre [Norwich] ; Biotechnology and Biological Sciences Research Council (BBSRC)-Biotechnology and Biological Sciences Research Council (BBSRC), Biotechnological and Biological Science Research Council BB/D018005/1 Australian Research Council A19927094 Spanish Government BIO2009-09920 Marie Curie Fellowship MEST-CT-2005-019727, Instituto de Biologia Molecular y Celular de Plantas (IBMCP) ; Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain] (CSIC)-Universitat Politècnica de Valènci

2011

Overview

Structural organization of organs in multicellular organisms occurs through intricate patterning mechanisms that often involve complex interactions between transcription factors in regulatory networks. For example, INDEHISCENT (IND), a basic helix-loop-helix (bHLH) transcription factor, specifies formation of the narrow stripes of valve margin tissue, where Arabidopsis thaliana fruits open on maturity. Another bHLH transcription factor, SPATULA (SPT), is required for reproductive tissue development from carpel margins in the Arabidopsis gynoecium before fertilization. Previous studies have therefore assigned the function of SPT to early gynoecium stages and IND to later fruit stages of reproductive development. Here we report that these two transcription factors interact genetically and via protein-protein contact to mediate both gynoecium development and fruit opening. We show that IND directly and positively regulates the expression of SPT, and that spt mutants have partial defects in valve margin formation. Careful analysis of ind mutant gynoecia revealed slight defects in apical tissue formation, and combining mutations in IND and SPT dramatically enhanced both single-mutant phenotypes. Our data show that SPT and IND at least partially mediate their joint functions in gynoecium and fruit development by controlling auxin distribution and suggest that this occurs through cooperative binding to regulatory sequences in downstream target genes.

• Publisher: American Society of Plant Biologists (ASPB),CCSD,American Society of Plant Biologists
• Subject: Arabidopsis / Arabidopsis - cytology / Arabidopsis - genetics / Arabidopsis - growth & development / Arabidopsis - physiology / Arabidopsis Proteins / Arabidopsis Proteins - genetics / Arabidopsis Proteins - metabolism / Arabidopsis thaliana / Auxins / Basic helix loop helix transcription factors / Basic Helix-Loop-Helix Transcription Factors - genetics / Basic Helix-Loop-Helix Transcription Factors - metabolism / Carpels / cytology / Developmental biology / Flower stigma / Flowers / Flowers - cytology / Flowers - genetics / Flowers - growth & development / Flowers - physiology / Fruit / Fruit - cytology / Fruit - genetics / Fruit - growth & development / Fruit - physiology / fruit maturity / fruiting / Fruits / Gene expression regulation / Gene Expression Regulation, Plant / Gene Expression Regulation, Plant - physiology / gene targeting / genetics / growth & development / Gynoecium / Indoleacetic Acids / Indoleacetic Acids - metabolism / Life Sciences / metabolism / Mutation / Phenotype / physiology / Plant cells / Plants / Protein Interaction Mapping / regulatory sequences / Regulatory Sequences, Nucleic Acid / Regulatory Sequences, Nucleic Acid - genetics / Reproduction / Reproduction - physiology / Seed dispersal / Seed Dispersal - physiology / Seeds / Seeds - genetics / Seeds - growth & development / Seeds - physiology / Yeasts
• ISBN: 0002981759000