title: High lipid order of Arabidopsis cell-plate membranes mediated by sterol and DYNAMIN-RELATED PROTEIN1A function.
abstract: Membranes of eukaryotic cells contain high lipid-order sterol-rich domains that are thought to mediate temporal and spatial organization of cellular processes. Sterols are crucial for execution of cytokinesis, the last stage of cell division, in diverse eukaryotes. The cell plate of higher-plant cells is the membrane structure that separates daughter cells during somatic cytokinesis. Cell-plate formation in Arabidopsis relies on sterol- and DYNAMIN-RELATED PROTEIN1A (DRP1A)-dependent endocytosis. However, functional relationships between lipid membrane order or lipid packing and endocytic machinery components during eukaryotic cytokinesis have not been elucidated. Using ratiometric live imaging of lipid order-sensitive fluorescent probes, we show that the cell plate of Arabidopsis thaliana represents a dynamic, high lipid-order membrane domain. The cell-plate lipid order was found to be sensitive to pharmacological and genetic alterations of sterol composition. Sterols co-localize with DRP1A at the cell plate, and DRP1A accumulates in detergent-resistant membrane fractions. Modifications of sterol concentration or composition reduce cell-plate membrane order and affect DRP1A localization. Strikingly, DRP1A function itself is essential for high lipid order at the cell plate. Our findings provide evidence that the cell plate represents a high lipid-order domain, and pave the way to explore potential feedback between lipid order and function of dynamin-related proteins during cytokinesis.
authors.affiliation: Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, SE-90187, Umeå, Sweden.
authors.forename: Márcia
authors.initials: M
authors.lastname: Frescatada-Rosa
authors.forename: Thomas
authors.initials: T
authors.lastname: Stanislas
authors.forename: Steven K
authors.initials: SK
authors.lastname: Backues
authors.forename: Ilka
authors.initials: I
authors.lastname: Reichardt
authors.forename: Shuzhen
authors.initials: S
authors.lastname: Men
authors.forename: Yohann
authors.initials: Y
authors.lastname: Boutté
authors.forename: Gerd
authors.initials: G
authors.lastname: Jürgens
authors.forename: Thomas
authors.initials: T
authors.lastname: Moritz
authors.forename: Sebastian Y
authors.initials: SY
authors.lastname: Bednarek
authors.forename: Markus
authors.initials: M
authors.lastname: Grebe
mesh_terms: D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism*; D003902:Detergents / Q000737:chemistry; D034281:Dynamins / Q000235:genetics / Q000378:metabolism*; D004705:Endocytosis; D008563:Membrane Lipids / Q000737:chemistry* / Q000378:metabolism; D009154:Mutation; D011726:Pyridinium Compounds / Q000032:analysis / Q000378:metabolism; D013261:Sterols / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D003902:Detergents; D008563:Membrane Lipids; D011726:Pyridinium Compounds; D013261:Sterols; C541550:di-4-ANEPPDHQ; C475162:ADL1A protein, Arabidopsis; D034281:Dynamins
keywords: Arabidopsis; DRP1A; cytokinesis; membrane order; sterol