title: Computer simulations reveal properties of the cell-cell signaling network at the shoot apex in Arabidopsis.
abstract: The active transport of the plant hormone auxin plays a major role in the initiation of organs at the shoot apex. Polar localized membrane proteins of the PIN1 family facilitate this transport, and recent observations suggest that auxin maxima created by these proteins are at the basis of organ initiation. This hypothesis is based on the visual, qualitative characterization of the complex distribution patterns of the PIN1 protein in Arabidopsis. To take these analyses further, we investigated the properties of the patterns using computational modeling. The simulations reveal previously undescribed properties of PIN1 distribution. In particular, they suggest an important role for the meristem summit in the distribution of auxin. We confirm these predictions by further experimentation and propose a detailed model for the dynamics of auxin fluxes at the shoot apex.
authors.affiliation: Institut National de la Recherche Agronomique, Unité Mixte de Recherche Botanique et Bio-informatique de l'Architecture des Plantes, TA40/PSII Boulevard de la Lironde, 34398 Montpellier Cedex 5, France.
authors.forename: Pierre Barbier
authors.initials: PB
authors.lastname: de Reuille
authors.forename: Isabelle
authors.initials: I
authors.lastname: Bohn-Courseau
authors.forename: Karin
authors.initials: K
authors.lastname: Ljung
authors.forename: Halima
authors.initials: H
authors.lastname: Morin
authors.forename: Nicola
authors.initials: N
authors.lastname: Carraro
authors.forename: Christophe
authors.initials: C
authors.lastname: Godin
authors.forename: Jan
authors.initials: J
authors.lastname: Traas
mesh_terms: D017360:Arabidopsis / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D001692:Biological Transport; D002450:Cell Communication; D002462:Cell Membrane / Q000378:metabolism; D002849:Chromatography, Gas; D003198:Computer Simulation; D018506:Gene Expression Regulation, Plant; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism; D013058:Mass Spectrometry; D026901:Membrane Transport Proteins / Q000378:metabolism; D018519:Meristem / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D010937:Plant Growth Regulators; D018521:Plant Physiological Phenomena; D018517:Plant Roots; D015398:Signal Transduction
chemical_list: C100794:AUX1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D026901:Membrane Transport Proteins; C116363:PIN1 protein, Arabidopsis; D010937:Plant Growth Regulators; D049452:Green Fluorescent Proteins