title: Competitive canalization of PIN-dependent auxin flow from axillary buds controls pea bud outgrowth.
abstract: Shoot branching is one of the major determinants of plant architecture. Polar auxin transport in stems is necessary for the control of bud outgrowth by a dominant apex. Here, we show that following decapitation in pea (Pisum sativum L.), the axillary buds establish directional auxin export by subcellular polarization of PIN auxin transporters. Apical auxin application on the decapitated stem prevents this PIN polarization and canalization of laterally applied auxin. These results support a model in which the apical and lateral auxin sources compete for primary channels of auxin transport in the stem to control the outgrowth of axillary buds.
authors.affiliation: Department of Plant Biology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.
authors.forename: Jozef
authors.initials: J
authors.lastname: Balla
authors.forename: Petr
authors.initials: P
authors.lastname: Kalousek
authors.forename: Vilém
authors.initials: V
authors.lastname: Reinöhl
authors.forename: Jiří
authors.initials: J
authors.lastname: Friml
authors.forename: Stanislav
authors.initials: S
authors.lastname: Procházka
mesh_terms: D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D018532:Pisum sativum / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018547:Plant Stems / Q000254:growth & development / Q000378:metabolism*
chemical_list: D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins