title: Emergence of tissue polarization from synergy of intracellular and extracellular auxin signaling.
abstract: Plant development is exceptionally flexible as manifested by its potential for organogenesis and regeneration, which are processes involving rearrangements of tissue polarities. Fundamental questions concern how individual cells can polarize in a coordinated manner to integrate into the multicellular context. In canalization models, the signaling molecule auxin acts as a polarizing cue, and feedback on the intercellular auxin flow is key for synchronized polarity rearrangements. We provide a novel mechanistic framework for canalization, based on up-to-date experimental data and minimal, biologically plausible assumptions. Our model combines the intracellular auxin signaling for expression of PINFORMED (PIN) auxin transporters and the theoretical postulation of extracellular auxin signaling for modulation of PIN subcellular dynamics. Computer simulations faithfully and robustly recapitulated the experimentally observed patterns of tissue polarity and asymmetric auxin distribution during formation and regeneration of vascular systems and during the competitive regulation of shoot branching by apical dominance. Additionally, our model generated new predictions that could be experimentally validated, highlighting a mechanistically conceivable explanation for the PIN polarization and canalization of the auxin flow in plants.
authors.affiliation: Department of Plant Systems Biology, VIB, Ghent University, Gent, Belgium.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Wabnik
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kleine-Vehn
authors.forename: Jozef
authors.initials: J
authors.lastname: Balla
authors.forename: Michael
authors.initials: M
authors.lastname: Sauer
authors.forename: Satoshi
authors.initials: S
authors.lastname: Naramoto
authors.forename: Vilém
authors.initials: V
authors.lastname: Reinöhl
authors.forename: Roeland M H
authors.initials: RM
authors.lastname: Merks
authors.forename: Willy
authors.initials: W
authors.lastname: Govaerts
authors.forename: Jiří
authors.initials: J
authors.lastname: Friml
mesh_terms: D017360:Arabidopsis / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D016764:Cell Polarity; D003198:Computer Simulation; D005110:Extracellular Space / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000737:chemistry* / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D058526:Plant Vascular Bundle / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D026901:Membrane Transport Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins