title: A Model of Differential Growth-Guided Apical Hook Formation in Plants.
abstract: Differential cell growth enables flexible organ bending in the presence of environmental signals such as light or gravity. A prominent example of the developmental processes based on differential cell growth is the formation of the apical hook that protects the fragile shoot apical meristem when it breaks through the soil during germination. Here, we combined in silico and in vivo approaches to identify a minimal mechanism producing auxin gradient-guided differential growth during the establishment of the apical hook in the model plant Arabidopsis thaliana Computer simulation models based on experimental data demonstrate that asymmetric expression of the PIN-FORMED auxin efflux carrier at the concave (inner) versus convex (outer) side of the hook suffices to establish an auxin maximum in the epidermis at the concave side of the apical hook. Furthermore, we propose a mechanism that translates this maximum into differential growth, and thus curvature, of the apical hook. Through a combination of experimental and in silico computational approaches, we have identified the individual contributions of differential cell elongation and proliferation to defining the apical hook and reveal the role of auxin-ethylene crosstalk in balancing these two processes.
authors.affiliation: Department of Plant Systems Biology, VIB, Gent 9052, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, Gent 9052, Belgium.
authors.forename: Petra
authors.initials: P
authors.lastname: Žádníková
authors.affiliation: Institute of Science and Technology Austria, Klosterneuburg 3400, Austria.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Wabnik
authors.affiliation: Department of Plant Systems Biology, VIB, Gent 9052, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, Gent 9052, Belgium.
authors.forename: Anas
authors.initials: A
authors.lastname: Abuzeineh
authors.affiliation: Institute of Science and Technology Austria, Klosterneuburg 3400, Austria.
authors.forename: Marçal
authors.identifier: 0000-0003-4675-6893
authors.initials: M
authors.lastname: Gallemi
authors.affiliation: Laboratory of Functional Plant Biology, Department of Physiology, Ghent University, Gent 9000, Belgium.
authors.forename: Dominique
authors.identifier: 0000-0002-7755-1420
authors.initials: D
authors.lastname: Van Der Straeten
authors.affiliation: Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Köln 50829, Germany.
authors.forename: Richard S
authors.identifier: 0000-0001-9220-0787
authors.initials: RS
authors.lastname: Smith
authors.affiliation: Department of Plant Systems Biology, VIB, Gent 9052, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, Gent 9052, Belgium.
authors.forename: Dirk
authors.identifier: 0000-0002-3217-8407
authors.initials: D
authors.lastname: Inzé
authors.affiliation: Institute of Science and Technology Austria, Klosterneuburg 3400, Austria.
authors.forename: Jiří
authors.identifier: 0000-0002-8302-7596
authors.initials: J
authors.lastname: Friml
authors.affiliation: Department of Computer Science, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
authors.forename: Przemysław
authors.initials: P
authors.lastname: Prusinkiewicz
authors.affiliation: Institute of Science and Technology Austria, Klosterneuburg 3400, Austria eva.benkova@ist.ac.at.
authors.forename: Eva
authors.identifier: 0000-0002-8510-9739
authors.initials: E
authors.lastname: Benková
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003198:Computer Simulation; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins