title: Meristem maintenance, auxin, jasmonic and abscisic acid pathways as a mechanism for phenotypic plasticity in Antirrhinum majus.
abstract: Plants grow under climatic changing conditions that cause modifications in vegetative and reproductive development. The degree of changes in organ development i.e. its phenotypic plasticity seems to be determined by the organ identity and the type of environmental cue. We used intraspecific competition and found that Antirrhinum majus behaves as a decoupled species for lateral organ size and number. Crowding causes decreases in leaf size and increased leaf number whereas floral size is robust and floral number is reduced. Genes involved in shoot apical meristem maintenance like ROA and HIRZ, cell cycle (CYCD3a; CYCD3b, HISTONE H4) or organ polarity (GRAM) were not significantly downregulated under crowding conditions. A transcriptomic analysis of inflorescence meristems showed Gene Ontology enriched pathways upregulated including Jasmonic and Abscisic acid synthesis and or signalling. Genes involved in auxin synthesis such as AmTAR2 and signalling AmANT were not affected by crowding. In contrast, AmJAZ1, AmMYB21, AmOPCL1 and AmABA2 were significantly upregulated. Our work provides a mechanistic working hypothesis where a robust SAM and stable auxin signalling enables a homogeneous floral size while changes in JA and ABA signalling maybe responsible for the decreased leaf size and floral number.
authors.affiliation: Genetica Molecular, Instituto de Biotecnología Vegetal, Universidad Politécnica de Cartagena, 30202 Cartagena, Spain.
authors.forename: Julia
authors.initials: J
authors.lastname: Weiss
authors.affiliation: Genetica Molecular, Instituto de Biotecnología Vegetal, Universidad Politécnica de Cartagena, 30202 Cartagena, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Alcantud-Rodriguez
authors.affiliation: Genetica Molecular, Instituto de Biotecnología Vegetal, Universidad Politécnica de Cartagena, 30202 Cartagena, Spain.
authors.forename: Tugba
authors.initials: T
authors.lastname: Toksöz
authors.affiliation: Genetica Molecular, Instituto de Biotecnología Vegetal, Universidad Politécnica de Cartagena, 30202 Cartagena, Spain.
authors.forename: Marcos
authors.initials: M
authors.lastname: Egea-Cortines
mesh_terms: D000040:Abscisic Acid / Q000235:genetics / Q000378:metabolism; D032161:Antirrhinum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D003517:Cyclopentanes / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D018519:Meristem / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D054883:Oxylipins / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics* / Q000254:growth & development; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified; D015398:Signal Transduction / Q000235:genetics
chemical_list: D003517:Cyclopentanes; D007210:Indoleacetic Acids; D054883:Oxylipins; D010940:Plant Proteins; D000040:Abscisic Acid; C086299:jasmone