title: Quantifying hydrostatic pressure in plant cells by using indentation with an atomic force microscope.
abstract: Plant cell growth depends on a delicate balance between an inner drive-the hydrostatic pressure known as turgor-and an outer restraint-the polymeric wall that surrounds a cell. The classical technique to measure turgor in a single cell, the pressure probe, is intrusive and cannot be applied to small cells. In order to overcome these limitations, we developed a method that combines quantification of topography, nanoindentation force measurements, and an interpretation using a published mechanical model for the pointlike loading of thin elastic shells. We used atomic force microscopy to estimate the elastic properties of the cell wall and turgor pressure from a single force-depth curve. We applied this method to onion epidermal peels and quantified the response to changes in osmolality of the bathing solution. Overall our approach is accessible and enables a straightforward estimation of the hydrostatic pressure inside a walled cell.
authors.affiliation: Laboratoire Reproduction et Développement des Plantes, Institut National de la Recherche Agronomique; Laboratoire Joliot-Curie, Centre National de la Recherche Scientifique, École Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France.
authors.forename: Léna
authors.initials: L
authors.lastname: Beauzamy
authors.affiliation: Laboratoire Matière et Systèmes Complexes, UMR 7057, Centre National de la Recherche Scientifique and Université Paris Diderot, Paris, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Derr
authors.affiliation: Laboratoire Reproduction et Développement des Plantes, Institut National de la Recherche Agronomique; Laboratoire Joliot-Curie, Centre National de la Recherche Scientifique, École Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France; Institut Universitaire de France, Paris, France. Electronic address: arezki.boudaoud@ens-lyon.fr.
authors.forename: Arezki
authors.initials: A
authors.lastname: Boudaoud
mesh_terms: D002473:Cell Wall / Q000378:metabolism; D004548:Elasticity; D006874:Hydrostatic Pressure; D018625:Microscopy, Atomic Force / Q000379:methods; D019697:Onions; D009994:Osmolar Concentration; D059828:Plant Cells / Q000378:metabolism*