Protocol for mapping the spatial variability in cell wall mechanical bending behavior in living leaf pavement cells

AbstractAn integrated, experimental-computational approach is presented to analyze the variation of elastic bending behavior in the primary cell wall of living Arabidopsis thaliana pavement cells and to measure turgor pressure in the cells quantitatively under different osmotic conditions. Mechanical properties, size and geometry of cells and internal turgor pressure greatly influence their morphogenesis. Computational models of plant morphogenesis require values for wall elastic modulus and turgor pressure but very few experiments were designed to validate the results using measurements that deform the entire thickness of the cell wall. Because new wall material is deposited from inside the cell, full-thickness deformations are needed to quantify relevant changes associated with cell development. The approach here uses laser scanning confocal microscopy to measure the three-dimensional geometry of a single pavement cell, and indentation experiments equipped with high magnification objective lens to probe the local mechanical responses across the same cell wall. These experimental results are matched iteratively using a finite element model of the experiment to determine the local mechanical properties, turgor pressure, and cell height. The resulting modulus distribution along the periclinal wall is shown to be nonuniform. These results are consistent with the characteristics of plant cell walls which have a heterogeneous organization. This research and the resulting model will provide a reference for future work associated with the heterogeneity and anisotropy of mechanical properties of plant cell walls in order to understand morphogenesis of the primary cell walls during growth and to predict quantitatively the magnitudes/directions of cell wall forces.One sentence summaryThe distribution of elastic modulus of the periclinal cell walls of livingArabidopsis epidermis is nonuniform as measured by bending the entire thickness of the wall.HighlightsExperimental characterization of the spatial distribution of elastic bending behavior across the periclinal wallQuantification of the turgor pressure of the living plant epidermal cells validated with osmotic treatmentsQuantification of the effect of cell geometry on the measured mechanical responseGraphical abstract

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Gradients of cell wall nano-mechanical properties along and across elongating primary roots of maize

Journal of Experimental Botany ◽

10.1093/jxb/eraa561 ◽

2020 ◽

Author(s):

Anna Petrova ◽

Tatyana Gorshkova ◽

Liudmila Kozlova

Keyword(s):

Mechanical Properties ◽

Cell Wall ◽

Cell Walls ◽

Computational Simulation ◽

Turgor Pressure ◽

Apical Part ◽

Elastic Response ◽

Elongation Zone ◽

Inner Cortex

Abstract To test the hypothesis that particular tissues can control root growth, we analysed mechanical properties of cell walls belonging to different tissues of the apical part of maize root using atomic-force microscopy. The dynamics of properties during elongation growth were characterised in four consecutive zones of the root. The extensive immunochemical characterization and quantification were used to establish the polysaccharide motif(s) related to changes in cell wall mechanics. Cell transition from division to elongation was coupled to the decrease in the elasticity modulus in all root tissues. Low values of moduli were retained in the elongation zone and increased in late elongation zone. No relationship between the immunolabelling pattern and mechanical properties of the cell walls was revealed. When measured values of elasticity moduli and turgor pressure were used in the computational simulation, this resulted in an elastic response of modelled root and the distribution of stress and strain similar with those observed in vivo. In all analysed root zones, cell walls of the inner cortex displayed moduli of elasticity that were maximal or comparable to the maximal values among all tissues. Thus, we propose that the inner cortex serves as a growth-limiting tissue in maize roots.

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Mechanical stress initiates and sustains the morphogenesis of wavy leaf epidermal cells

10.1101/563403 ◽

2019 ◽

Cited By ~ 3

Author(s):

Amir J Bidhendi ◽

Bara Altartouri ◽

Frédérick P. Gosselin ◽

Anja Geitmann

Keyword(s):

Mechanical Properties ◽

Cell Wall ◽

Cell Walls ◽

De Novo ◽

Epidermal Cells ◽

Cellulose Microfibrils ◽

List Type ◽

Pavement Cells ◽

Morphogenetic Process ◽

Cell Shapes

Plant cell morphogenesis is governed by the mechanical properties of the cell wall and the resulting cell shape is intimately related to the respective specific function. Pavement cells covering the surface of plant leaves form wavy interlocking patterns in many plants. We use computational mechanics to simulate the morphogenetic process based on experimentally assessed cell shapes, growth dynamics, and cell wall chemistry. The simulations and experimental evidence suggest a multistep process underlying the morphogenesis of pavement cells during tissue differentiation. The mechanical shaping process relies on spatially confined, feedback-augmented stiffening of the cell wall in the periclinal walls, an effect that correlates with experimentally observed deposition patterns of cellulose and de-esterified pectin. We provide evidence for mechanical buckling of the pavement cell walls that can robustly initiate patternsde novoand may precede chemical and geometrical anisotropy.HighlightsA multistep mechano-chemical morphogenetic process underlies the wavy pattern of epidermal pavement cells.Microtubule polarization is preceded by an event that breaks mechanical isotropy in the cell wall.Mechanical models simulate the formation of wavy cell shapes, predict buckling of the cell walls and spatially confined variations in the mechanical properties of leaf epidermal cells.Stress/strain stiffening following the buckling of the cell walls constitutes a crucial element in a positive feedback loop forming interlocking pavement cells.Polarization of cortical microtubules, cellulose microfibrils, and de-esterified pectin occur at the necks of wavy pavement cells, matching thein silicoprediction of cell wall stiffening.

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Plant Cell Wall Hydration and Plant Physiology: An Exploration of the Consequences of Direct Effects of Water Deficit on the Plant Cell Wall

Plants ◽

10.3390/plants10071263 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1263

Author(s):

David Stuart Thompson ◽

Azharul Islam

Keyword(s):

Cell Wall ◽

Water Content ◽

Bacterial Cellulose ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Plant Cell Walls ◽

Cell Wall Polysaccharides ◽

Degree Of Hydration ◽

Cellulose Composites

The extensibility of synthetic polymers is routinely modulated by the addition of lower molecular weight spacing molecules known as plasticizers, and there is some evidence that water may have similar effects on plant cell walls. Furthermore, it appears that changes in wall hydration could affect wall behavior to a degree that seems likely to have physiological consequences at water potentials that many plants would experience under field conditions. Osmotica large enough to be excluded from plant cell walls and bacterial cellulose composites with other cell wall polysaccharides were used to alter their water content and to demonstrate that the relationship between water potential and degree of hydration of these materials is affected by their composition. Additionally, it was found that expansins facilitate rehydration of bacterial cellulose and cellulose composites and cause swelling of plant cell wall fragments in suspension and that these responses are also affected by polysaccharide composition. Given these observations, it seems probable that plant environmental responses include measures to regulate cell wall water content or mitigate the consequences of changes in wall hydration and that it may be possible to exploit such mechanisms to improve crop resilience.

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A freeze-etch study of plant cell walls for ectodesmata

Canadian Journal of Botany ◽

10.1139/b74-260 ◽

1974 ◽

Vol 52 (9) ◽

pp. 2033-2036 ◽

Cited By ~ 7

Author(s):

N. C. Lyon ◽

W. C. Mueller

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Leaf Tissue ◽

Physicochemical Characteristics ◽

Outer Cell ◽

Plantago Major ◽

Plant Cell Walls ◽

Phaseolus Vulgaris L ◽

Epidermal Cell Wall ◽

Outer Cell Wall

Leaf tissue of Phaseolus vulgaris L. and Plantago major L. was prepared by the freeze-etch technique and examined in the electron microscope for the presence of ectodesmata. No structures analagous to ectodesmata observed with light microscopy could be found in freeze-etched preparations of chemically unfixed material or in material fixed only in glutaraldehyde. Objects appearing as broad, shallow, granular areas in the epidermal cell wall beneath the cuticle were observed in leaf replicas after fixation in complete sublimate fixative, the acid components of the sublimate fixative, or mercuric chloride alone. Because of their distribution and location, these objects can be considered analagous to ectodesmata observed by light microscopists. Because these areas occur only in chemically fixed walls and are localized within the walls in discrete areas, their presence supports the contention that ectodesmata are sites in the outer cell wall with defined physicochemical characteristics.

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A Label-free, Fast and High-specificity Technique for Plant Cell Wall Imaging and Composition Analysis

10.21203/rs.3.rs-107437/v1 ◽

2020 ◽

Author(s):

Huimin Xu ◽

Yuanyuan Zhao ◽

Yuanzhen Suo ◽

Yayu Guo ◽

Yi Man ◽

...

Keyword(s):

Cell Wall ◽

Chemical Composition ◽

Raman Scattering ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Wall ◽

Composition Analysis ◽

Plant Cell Walls ◽

Label Free ◽

Wall Imaging

Abstract Background: Cell wall imaging can considerably permit direct visualization of the molecular architecture of cell walls and provide the detailed chemical information on wall polymers, which is imperative to better exploit and use the biomass polymers; however, detailed imaging and quantifying of the native composition and architecture in the cell wall remains challenging.Results: Here, we describe a label-free imaging technology, coherent Raman scattering microscopy (CRS), including coherent anti-Stokes Raman scattering (CARS) microscopy and stimulated Raman scattering (SRS) microscopy, which images the major structures and chemical composition of plant cell walls. The major steps of the procedure are demonstrated, including sample preparation, setting the mapping parameters, analysis of spectral data, and image generation. Applying this rapid approach, which will help researchers understand the highly heterogeneous structures and organization of plant cell walls.Conclusions: This method can potentially be incorporated into label-free microanalyses of plant cell wall chemical composition based on the in situ vibrations of molecules.

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Roles of Cellulose and Xyloglucan in Determining the Mechanical Properties of Primary Plant Cell Walls

PLANT PHYSIOLOGY ◽

10.1104/pp.121.2.657 ◽

1999 ◽

Vol 121 (2) ◽

pp. 657-664 ◽

Cited By ~ 130

Author(s):

Sarah E.C. Whitney ◽

Michelle G.E. Gothard ◽

John T. Mitchell ◽

Michael J. Gidley

Keyword(s):

Mechanical Properties ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Walls

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Isolation and Characterization of Plant Cell Walls and Cell Wall Components

Methods for Plant Molecular Biology ◽

10.1016/b978-0-12-743655-5.50007-5 ◽

1988 ◽

pp. 3-40 ◽

Cited By ~ 2

Author(s):

WILLIAM S. YORK ◽

ALAN G. DARVILL ◽

MICHAEL MCNEIL ◽

THOMAS T. STEVENSON ◽

PETER ALBERSHEIM

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Walls ◽

Cell Wall Components ◽

Isolation And Characterization ◽

Wall Components

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Isolation and characterization of plant cell walls and cell wall components

Methods in Enzymology - Plant Molecular Biology ◽

10.1016/0076-6879(86)18062-1 ◽

1986 ◽

pp. 3-40 ◽

Cited By ~ 766

Author(s):

William S. York ◽

Alan G. Darvill ◽

Michael McNeil ◽

Thomas T. Stevenson ◽

Peter Albersheim

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plant Cell Walls ◽

Cell Wall Components ◽

Isolation And Characterization ◽

Wall Components

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Plasmodesmata-Related Structural and Functional Proteins: The Long Sought-After Secrets of a Cytoplasmic Channel in Plant Cell Walls

International Journal of Molecular Sciences ◽

10.3390/ijms20122946 ◽

2019 ◽

Vol 20 (12) ◽

pp. 2946 ◽

Cited By ~ 7

Author(s):

Xiao Han ◽

Li-Jun Huang ◽

Dan Feng ◽

Wenhan Jiang ◽

Wenzhuo Miu ◽

...

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Cell Walls ◽

Plasma Membranes ◽

Plant Cell Wall ◽

Plant Cells ◽

Protein Composition ◽

Cell Contact ◽

Plant Cell Walls ◽

Cell Organelles

Plant cells are separated by cellulose cell walls that impede direct cell-to-cell contact. In order to facilitate intercellular communication, plant cells develop unique cell-wall-spanning structures termed plasmodesmata (PD). PD are membranous channels that link the cytoplasm, plasma membranes, and endoplasmic reticulum of adjacent cells to provide cytoplasmic and membrane continuity for molecular trafficking. PD play important roles for the development and physiology of all plants. The structure and function of PD in the plant cell walls are highly dynamic and tightly regulated. Despite their importance, plasmodesmata are among the few plant cell organelles that remain poorly understood. The molecular properties of PD seem largely elusive or speculative. In this review, we firstly describe the general PD structure and its protein composition. We then discuss the recent progress in identification and characterization of PD-associated plant cell-wall proteins that regulate PD function, with particular emphasis on callose metabolizing and binding proteins, and protein kinases targeted to and around PD.

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