title: D6 PROTEIN KINASE activates auxin transport-dependent growth and PIN-FORMED phosphorylation at the plasma membrane.
abstract: The directed cell-to-cell transport of the phytohormone auxin by efflux and influx transporters is essential for proper plant growth and development. Like auxin efflux facilitators of the PIN-FORMED (PIN) family, D6 PROTEIN KINASE (D6PK) from Arabidopsis thaliana localizes to the basal plasma membrane of many cells, and evidence exists that D6PK may directly phosphorylate PINs. We find that D6PK is a membrane-bound protein that is associated with either the basal domain of the plasma membrane or endomembranes. Inhibition of the trafficking regulator GNOM leads to a rapid internalization of D6PK to endomembranes. Interestingly, the dissociation of D6PK from the plasma membrane is also promoted by auxin. Surprisingly, we find that auxin transport-dependent tropic responses are critically and reversibly controlled by D6PK and D6PK-dependent PIN phosphorylation at the plasma membrane. We conclude that D6PK abundance at the plasma membrane and likely D6PK-dependent PIN phosphorylation are prerequisites for PIN-mediated auxin transport.
authors.affiliation: Department of Plant Systems Biology, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany.
authors.forename: Inês C R
authors.initials: IC
authors.lastname: Barbosa
authors.affiliation: Department of Plant Systems Biology, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany.
authors.forename: Melina
authors.initials: M
authors.lastname: Zourelidou
authors.affiliation: Department of Plant Systems Biology, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany.
authors.forename: Björn C
authors.initials: BC
authors.lastname: Willige
authors.affiliation: Department of Plant Systems Biology, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Weller
authors.affiliation: Department of Plant Systems Biology, Center of Life and Food Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany. Electronic address: claus.schwechheimer@wzw.tum.de.
authors.forename: Claus
authors.initials: C
authors.lastname: Schwechheimer
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects; D002462:Cell Membrane / Q000378:metabolism*; D002966:Clathrin / Q000378:metabolism; D004705:Endocytosis; D018506:Gene Expression Regulation, Plant; D015151:Immunoblotting; D007210:Indoleacetic Acids / Q000494:pharmacology*; D026901:Membrane Transport Proteins / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D010937:Plant Growth Regulators / Q000494:pharmacology; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D002966:Clathrin; D007210:Indoleacetic Acids; D026901:Membrane Transport Proteins; C116363:PIN1 protein, Arabidopsis; D010937:Plant Growth Regulators; C585918:D6PK protein, Arabidopsis; D011494:Protein Kinases