title: CLASP-mediated cortical microtubule organization guides PIN polarization axis.
abstract: Recent evidence indicates a correlation between orientation of the plant cortical microtubule cytoskeleton and localization of polar cargoes. However, the molecules and mechanisms that create this correlation have remained unknown. Here we show that, in Arabidopsis thaliana, the microtubule orientation regulators CLASP and MAP65 (refs 3, 4) control the abundance of polarity regulator PINOID kinase at the plasma membrane. By localized upregulation of clathrin-dependent endocytosis at cortical microtubule- and clathrin-rich domains orthogonal to the axis of polarity, PINOID accelerates the removal of auxin transporter PIN proteins from those sites. This mechanism links directional microtubule organization to the polar localization of auxin transporter PIN proteins, and clarifies how microtubule-enriched cell sides are kept distinct from polar delivery domains. Our results identify the molecular machinery that connects microtubule organization to the regulation of the axis of PIN polarization.
authors.affiliation: Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
authors.forename: Klementina
authors.initials: K
authors.lastname: Kakar
authors.forename: Hongtao
authors.initials: H
authors.lastname: Zhang
authors.forename: Ben
authors.initials: B
authors.lastname: Scheres
authors.forename: Pankaj
authors.initials: P
authors.lastname: Dhonukshe
mesh_terms: D017360:Arabidopsis / Q000166:cytology* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D016764:Cell Polarity / Q000235:genetics / Q000502:physiology*; D002966:Clathrin / Q000378:metabolism; D004705:Endocytosis; D007210:Indoleacetic Acids / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D021381:Protein Transport
chemical_list: D029681:Arabidopsis Proteins; D002966:Clathrin; D007210:Indoleacetic Acids; D026901:Membrane Transport Proteins; D008869:Microtubule-Associated Proteins; D050505:Mutant Proteins; D017346:Protein Serine-Threonine Kinases; C527272:CLASP protein, Arabidopsis; C492901:MAP65-1 protein, Arabidopsis; C116363:PIN1 protein, Arabidopsis; C117013:AT5G57090 protein, Arabidopsis; C405165:PINOID protein, Arabidopsis