title: Patterning and lifetime of plasma membrane-localized cellulose synthase is dependent on actin organization in Arabidopsis interphase cells.
abstract: The actin and microtubule cytoskeletons regulate cell shape across phyla, from bacteria to metazoans. In organisms with cell walls, the wall acts as a primary constraint of shape, and generation of specific cell shape depends on cytoskeletal organization for wall deposition and/or cell expansion. In higher plants, cortical microtubules help to organize cell wall construction by positioning the delivery of cellulose synthase (CesA) complexes and guiding their trajectories to orient newly synthesized cellulose microfibrils. The actin cytoskeleton is required for normal distribution of CesAs to the plasma membrane, but more specific roles for actin in cell wall assembly and organization remain largely elusive. We show that the actin cytoskeleton functions to regulate the CesA delivery rate to, and lifetime of CesAs at, the plasma membrane, which affects cellulose production. Furthermore, quantitative image analyses revealed that actin organization affects CesA tracking behavior at the plasma membrane and that small CesA compartments were associated with the actin cytoskeleton. By contrast, localized insertion of CesAs adjacent to cortical microtubules was not affected by the actin organization. Hence, both actin and microtubule cytoskeletons play important roles in regulating CesA trafficking, cellulose deposition, and organization of cell wall biogenesis.
authors.affiliation: Sainsbury Laboratory, University of Cambridge, Cambridge CB2 1LR, United Kingdom.
authors.forename: Arun
authors.initials: A
authors.lastname: Sampathkumar
authors.forename: Ryan
authors.initials: R
authors.lastname: Gutierrez
authors.forename: Heather E
authors.initials: HE
authors.lastname: McFarlane
authors.forename: Martin
authors.initials: M
authors.lastname: Bringmann
authors.forename: Jelmer
authors.initials: J
authors.lastname: Lindeboom
authors.forename: Anne-Mie
authors.initials: AM
authors.lastname: Emons
authors.forename: Lacey
authors.initials: L
authors.lastname: Samuels
authors.forename: Tijs
authors.initials: T
authors.lastname: Ketelaar
authors.forename: David W
authors.initials: DW
authors.lastname: Ehrhardt
authors.forename: Staffan
authors.initials: S
authors.lastname: Persson
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000199:Actins / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism; D001483:Base Sequence; D002462:Cell Membrane / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D005089:Exocytosis; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism*; D006056:Golgi Apparatus; D018546:Hypocotyl / Q000166:cytology / Q000378:metabolism; D007399:Interphase; D008870:Microtubules / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation
chemical_list: D000199:Actins; D029681:Arabidopsis Proteins; D002482:Cellulose; D005964:Glucosyltransferases; C478648:cellulose synthase