title: Cytokinin signalling inhibitory fields provide robustness to phyllotaxis.
abstract: How biological systems generate reproducible patterns with high precision is a central question in science. The shoot apical meristem (SAM), a specialized tissue producing plant aerial organs, is a developmental system of choice to address this question. Organs are periodically initiated at the SAM at specific spatial positions and this spatiotemporal pattern defines phyllotaxis. Accumulation of the plant hormone auxin triggers organ initiation, whereas auxin depletion around organs generates inhibitory fields that are thought to be sufficient to maintain these patterns and their dynamics. Here we show that another type of hormone-based inhibitory fields, generated directly downstream of auxin by intercellular movement of the cytokinin signalling inhibitor ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN 6 (AHP6), is involved in regulating phyllotactic patterns. We demonstrate that AHP6-based fields establish patterns of cytokinin signalling in the meristem that contribute to the robustness of phyllotaxis by imposing a temporal sequence on organ initiation. Our findings indicate that not one but two distinct hormone-based fields may be required for achieving temporal precision during formation of reiterative structures at the SAM, thus indicating an original mechanism for providing robustness to a dynamic developmental system.
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2] IBENS, ENS, 75005 Paris, France (F.B.); UMR CNRS 5534, Université Claude Bernard Lyon I, Bâtiment Gregor Mendel, 16 rue Raphaël Dubois, 69622 Villeurbanne, France (V.M.); University of Nottingham, University Park, Nottingham NG7 2RD, UK (E.F); University of Nottingham, Sutton Bonington LE12 5RD, UK (A.Bi.).
authors: Fabrice
authors: F
authors: Besnard
authors: Virtual Plants INRIA/CIRAD/INRA Project Team, UMR AGAP, Institut de Biologie Computationelle, 34095 Montpellier, France.
authors: Yassin
authors: Y
authors: Refahi
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2] IBENS, ENS, 75005 Paris, France (F.B.); UMR CNRS 5534, Université Claude Bernard Lyon I, Bâtiment Gregor Mendel, 16 rue Raphaël Dubois, 69622 Villeurbanne, France (V.M.); University of Nottingham, University Park, Nottingham NG7 2RD, UK (E.F); University of Nottingham, Sutton Bonington LE12 5RD, UK (A.Bi.). [3].
authors: Valérie
authors: V
authors: Morin
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2].
authors: Benjamin
authors: B
authors: Marteaux
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2].
authors: Géraldine
authors: G
authors: Brunoud
authors: Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France.
authors: Pierre
authors: P
authors: Chambrier
authors: Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France.
authors: Frédérique
authors: F
authors: Rozier
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2] Laboratoire Joliot-Curie, CNRS, ENS Lyon, Université de Lyon, 69364 Lyon, France.
authors: Vincent
authors: V
authors: Mirabet
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2] Virtual Plants INRIA/CIRAD/INRA Project Team, UMR AGAP, Institut de Biologie Computationelle, 34095 Montpellier, France [3] Laboratoire Joliot-Curie, CNRS, ENS Lyon, Université de Lyon, 69364 Lyon, France.
authors: Jonathan
authors: J
authors: Legrand
authors: Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France.
authors: Stéphanie
authors: S
authors: Lainé
authors: Laboratoire Physiologie Cellulaire et Végétale, CEA, CNRS, INRA, UJF, 38041 Grenoble, France.
authors: Emmanuel
authors: E
authors: Thévenon
authors: 1] Virtual Plants INRIA/CIRAD/INRA Project Team, UMR AGAP, Institut de Biologie Computationelle, 34095 Montpellier, France [2] IBENS, ENS, 75005 Paris, France (F.B.); UMR CNRS 5534, Université Claude Bernard Lyon I, Bâtiment Gregor Mendel, 16 rue Raphaël Dubois, 69622 Villeurbanne, France (V.M.); University of Nottingham, University Park, Nottingham NG7 2RD, UK (E.F); University of Nottingham, Sutton Bonington LE12 5RD, UK (A.Bi.).
authors: Etienne
authors: E
authors: Farcot
authors: Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France.
authors: Coralie
authors: C
authors: Cellier
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2] Laboratoire Joliot-Curie, CNRS, ENS Lyon, Université de Lyon, 69364 Lyon, France.
authors: Pradeep
authors: P
authors: Das
authors: 1] Institute of Biotechnology/Department of Biosciences, University of Helsinki, FIN-00014, Finland [2] IBENS, ENS, 75005 Paris, France (F.B.); UMR CNRS 5534, Université Claude Bernard Lyon I, Bâtiment Gregor Mendel, 16 rue Raphaël Dubois, 69622 Villeurbanne, France (V.M.); University of Nottingham, University Park, Nottingham NG7 2RD, UK (E.F); University of Nottingham, Sutton Bonington LE12 5RD, UK (A.Bi.).
authors: Anthony
authors: A
authors: Bishopp
authors: Laboratoire Physiologie Cellulaire et Végétale, CEA, CNRS, INRA, UJF, 38041 Grenoble, France.
authors: Renaud
authors: R
authors: Dumas
authors: Laboratoire Physiologie Cellulaire et Végétale, CEA, CNRS, INRA, UJF, 38041 Grenoble, France.
authors: François
authors: F
authors: Parcy
authors: Institute of Biotechnology/Department of Biosciences, University of Helsinki, FIN-00014, Finland.
authors: Ykä
authors: Y
authors: Helariutta
authors: 1] Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France [2] Laboratoire Joliot-Curie, CNRS, ENS Lyon, Université de Lyon, 69364 Lyon, France.
authors: Arezki
authors: A
authors: Boudaoud
authors: Virtual Plants INRIA/CIRAD/INRA Project Team, UMR AGAP, Institut de Biologie Computationelle, 34095 Montpellier, France.
authors: Christophe
authors: C
authors: Godin
authors: Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France.
authors: Jan
authors: J
authors: Traas
authors: Virtual Plants INRIA/CIRAD/INRA Project Team, UMR AGAP, Institut de Biologie Computationelle, 34095 Montpellier, France.
authors: Yann
authors: Y
authors: Guédon
authors: Laboratoire de Reproduction et Développement des Plantes, CNRS, INRA, ENS Lyon, UCBL, Université de Lyon, 69364 Lyon, France.
authors: Teva
authors: T
authors: Vernoux
mesh_terms: D017360:Arabidopsis / Q000033:anatomy & histology / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001692:Biological Transport; D003583:Cytokinins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism; D018519:Meristem / Q000378:metabolism; D010937:Plant Growth Regulators / Q000037:antagonists & inhibitors / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D015398:Signal Transduction
chemical_list: C507179:AHP6 protein, Arabidopsis; D029681:Arabidopsis Proteins; D003583:Cytokinins; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators