title: Cellular force microscopy for in vivo measurements of plant tissue mechanics.
abstract: Although growth and morphogenesis are controlled by genetics, physical shape change in plant tissue results from a balance between cell wall loosening and intracellular pressure. Despite recent work demonstrating a role for mechanical signals in morphogenesis, precise measurement of mechanical properties at the individual cell level remains a technical challenge. To address this challenge, we have developed cellular force microscopy (CFM), which combines the versatility of classical microindentation techniques with the high automation and resolution approaching that of atomic force microscopy. CFM's large range of forces provides the possibility to map the apparent stiffness of both plasmolyzed and turgid tissue as well as to perform micropuncture of cells using very high stresses. CFM experiments reveal that, within a tissue, local stiffness measurements can vary with the level of turgor pressure in an unexpected way. Altogether, our results highlight the importance of detailed physically based simulations for the interpretation of microindentation results. CFM's ability to be used both to assess and manipulate tissue mechanics makes it a method of choice to unravel the feedbacks between mechanics, genetics, and morphogenesis.
authors.affiliation: Institute of Plant Sciences, University of Bern, CH-3013 Bern, Switzerland.
authors.forename: Anne-Lise
authors.initials: AL
authors.lastname: Routier-Kierzkowska
authors.forename: Alain
authors.initials: A
authors.lastname: Weber
authors.forename: Petra
authors.initials: P
authors.lastname: Kochova
authors.forename: Dimitris
authors.initials: D
authors.lastname: Felekis
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Nelson
authors.forename: Cris
authors.initials: C
authors.lastname: Kuhlemeier
authors.forename: Richard S
authors.initials: RS
authors.lastname: Smith
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology; D002473:Cell Wall / Q000648:ultrastructure; D018625:Microscopy, Atomic Force / Q000379:methods*; D019697:Onions / Q000648:ultrastructure; D009928:Organ Specificity; D059828:Plant Cells / Q000502:physiology*; D019441:Plant Epidermis / Q000648:ultrastructure; D011312:Pressure