title: Atomic force microscopy stiffness tomography on living Arabidopsis thaliana cells reveals the mechanical properties of surface and deep cell-wall layers during growth.
abstract: Cell-wall mechanical properties play a key role in the growth and the protection of plants. However, little is known about genuine wall mechanical properties and their growth-related dynamics at subcellular resolution and in living cells. Here, we used atomic force microscopy (AFM) stiffness tomography to explore stiffness distribution in the cell wall of suspension-cultured Arabidopsis thaliana as a model of primary, growing cell wall. For the first time that we know of, this new imaging technique was performed on living single cells of a higher plant, permitting monitoring of the stiffness distribution in cell-wall layers as a function of the depth and its evolution during the different growth phases. The mechanical measurements were correlated with changes in the composition of the cell wall, which were revealed by Fourier-transform infrared (FTIR) spectroscopy. In the beginning and end of cell growth, the average stiffness of the cell wall was low and the wall was mechanically homogenous, whereas in the exponential growth phase, the average wall stiffness increased, with increasing heterogeneity. In this phase, the difference between the superficial and deep wall stiffness was highest. FTIR spectra revealed a relative increase in the polysaccharide/lignin content.
authors.affiliation: Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia. Electronic address: xenia@imsi.rs.
authors.forename: Ksenija
authors.initials: K
authors.lastname: Radotić
authors.affiliation: Département de Biologie Cellulaire et de Morphologie, Université de Lausanne, Lausanne, Switzerland.
authors.forename: Charles
authors.initials: C
authors.lastname: Roduit
authors.affiliation: Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.
authors.forename: Jasna
authors.initials: J
authors.lastname: Simonović
authors.affiliation: Center for Integrative Genomics, Université de Lausanne, Lausanne, Switzerland.
authors.forename: Patricia
authors.initials: P
authors.lastname: Hornitschek
authors.affiliation: Center for Integrative Genomics, Université de Lausanne, Lausanne, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Fankhauser
authors.affiliation: Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.
authors.forename: Dragosav
authors.initials: D
authors.lastname: Mutavdžić
authors.affiliation: Hungarian Academy of Sciences, Biological Research Centre, Szeged, Hungary.
authors.forename: Gabor
authors.initials: G
authors.lastname: Steinbach
authors.affiliation: Laboratoire de Physique de la Matière Vivante, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Dietler
authors.affiliation: Laboratoire de Physique de la Matière Vivante, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Département de Biologie Cellulaire et de Morphologie, Université de Lausanne, Lausanne, Switzerland.
authors.forename: Sandor
authors.initials: S
authors.lastname: Kasas
mesh_terms: D017360:Arabidopsis / Q000166:cytology* / Q000254:growth & development*; D001696:Biomechanical Phenomena; D002473:Cell Wall; D046508:Culture Techniques; D055595:Mechanical Phenomena; D018625:Microscopy, Atomic Force; D013499:Surface Properties; D014054:Tomography