title: Spatio-temporal analysis of cellulose synthesis during cell plate formation in Arabidopsis.
abstract: During cytokinesis a new crosswall is rapidly laid down. This process involves the formation at the cell equator of a tubulo-vesicular membrane network (TVN). This TVN evolves into a tubular network (TN) and a planar fenestrated sheet, which extends at its periphery before fusing to the mother cell wall. The role of cell wall polymers in cell plate assembly is poorly understood. We used specific stains and GFP-labelled cellulose synthases (CESAs) to show that cellulose, as well as three distinct CESAs, accumulated in the cell plate already at the TVN stage. This early presence suggests that cellulose is extruded into the tubular membrane structures of the TVN. Co-localisation studies using GFP-CESAs suggest the delivery of cellulose synthase complexes (CSCs) to the cell plate via phragmoplast-associated vesicles. In the more mature TN part of the cell plate, we observed delivery of GFP-CESA from doughnut-shaped organelles, presumably Golgi bodies. During the conversion of the TN into a planar fenestrated sheet, the GFP-CESA density diminished, whereas GFP-CESA levels remained high in the TVN zone at the periphery of the expanding cell plate. We observed retrieval of GFP-CESA in clathrin-containing structures from the central zone of the cell plate and from the plasma membrane of the mother cell, which may contribute to the recycling of CESAs to the peripheral growth zone of the cell plate. These observations, together with mutant phenotypes of cellulose-deficient mutants and pharmacological experiments, suggest a key role for cellulose synthesis already at early stages of cell plate assembly.
authors.affiliation: INRA, UMR1318, Institut Jean-Pierre Bourgin, Saclay Plant Sciences, AgroParisTech, RD10, F-78000, Versailles, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Miart
authors.forename: Thierry
authors.initials: T
authors.lastname: Desprez
authors.forename: Eric
authors.initials: E
authors.lastname: Biot
authors.forename: Halima
authors.initials: H
authors.lastname: Morin
authors.forename: Katia
authors.initials: K
authors.lastname: Belcram
authors.forename: Herman
authors.initials: H
authors.lastname: Höfte
authors.forename: Martine
authors.initials: M
authors.lastname: Gonneau
authors.forename: Samantha
authors.initials: S
authors.lastname: Vernhettes
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002455:Cell Division; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D002473:Cell Wall / Q000378:metabolism* / Q000648:ultrastructure; D002482:Cellulose / Q000378:metabolism*; D002966:Clathrin / Q000378:metabolism; D048749:Cytokinesis; D017930:Genes, Reporter; D005964:Glucosyltransferases / Q000235:genetics* / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism / Q000648:ultrastructure; D007527:Isoenzymes; D018613:Microscopy, Confocal; D008870:Microtubules / Q000648:ultrastructure; D008954:Models, Biological; D018517:Plant Roots / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011993:Recombinant Fusion Proteins; D036226:Seedlings / Q000166:cytology / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002966:Clathrin; D007527:Isoenzymes; D011993:Recombinant Fusion Proteins; D002482:Cellulose; C110227:CESA1 protein, Arabidopsis; D005964:Glucosyltransferases
keywords: Arabidopsis thaliana; cell plate; cell wall; cellulose synthase; cytokinesis; membrane trafficking; phragmoplast microtubule