Stem integrity inArabidopsis thalianarequires a load-bearing epidermis

ABSTRACTBecause plant cells are glued to each other via their cell walls, failure to coordinate growth among adjacent cells can create cracks in tissues. Here, we find that the unbalanced growth of inner and outer tissues in theclavata3 de-etiolated3(clv3 det3) mutant ofArabidopsis thalianastretched epidermal cells, ultimately generating cracks in stems. Stem growth slowed before cracks appeared alongclv3 det3stems, whereas inner pith cells became drastically distorted and accelerated their growth, yielding to stress, after the appearance of cracks. This is consistent with a key role of the epidermis in restricting growth. Mechanical property measurements recorded using an atomic force microscope revealed that epidermal cell wall stiffness decreased indet3andclv3 det3epidermises. Thus, we hypothesized that stem integrity depends on the epidermal resistance to mechanical stress. To formally test this hypothesis, we used theDET3gene as part of a tissue-specific strategy to complement cell expansion defects. Epidermis-driven DET3 expression restored growth and restored the frequency of stem cracking to 20% of theclv3 det3mutant, demonstrating the DET3-dependent load-bearing role of the epidermis.

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Reduced Cell Expansion and Changes in Cell Walls of Plant Cells Adapted to NaCl

Environmental Injury to Plants ◽

10.1016/b978-0-12-401350-6.50011-4 ◽

1990 ◽

pp. 137-171 ◽

Cited By ~ 27

Author(s):

Ray A. Bressan ◽

Donald E. Nelson ◽

Naim M. Iraki ◽

P. Christopher LaRosa ◽

Narendra K. Singh ◽

...

Keyword(s):

Cell Expansion ◽

Cell Walls ◽

Plant Cells

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Electrostatic effects and the dynamics of enzyme reactions at the surface of plant cells. 2. The role of pectin methyl esterase in the modulation of electrostatic effects in soybean cell walls

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1986.tb09476.x ◽

1986 ◽

Vol 155 (1) ◽

pp. 191-197 ◽

Cited By ~ 48

Author(s):

Anne-Marie MOUSTACAS ◽

Johanes NARI ◽

Gregoire DIAMANTIDIS ◽

Georges NOAT ◽

Martine CRASNIER ◽

...

Keyword(s):

Cell Walls ◽

Plant Cells ◽

Pectin Methyl Esterase ◽

Electrostatic Effects ◽

Enzyme Reactions ◽

Soybean Cell

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Role of Golgi Apparatus in the Formation of Plant Slimes, Cuticles and Extraneous Wall Material

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050445 ◽

1974 ◽

Vol 32 ◽

pp. 86-87

Author(s):

Hilton H. Mollenhauer

Keyword(s):

Cell Wall ◽

Golgi Apparatus ◽

Cell Walls ◽

Growth And Development ◽

Characteristic Property ◽

Plant Cells ◽

Plant Biology ◽

Wall Material ◽

Wall Properties

Cell walls are fundamentally involved in many aspects of plant biology including the morphology, growth, and development of plant cells and the interactions between plant hosts and their pathogens. Intuitively, one can recognize that these wall properties result from the sum total of the various components of which the wall is composed and that there are classes of substances each of which impart a characteristic property to the cell wall.

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Radially transmitted changes in hydraulic and osmotic pressures help explain reversible and irreversible patterns of tree stem expansion

10.22541/au.162482206.67739360/v1 ◽

2021 ◽

Author(s):

Sebastian Pfautsch ◽

John Drake ◽

Mike Aspinwall ◽

Victor Resco de Dios ◽

Craig Barton ◽

...

Keyword(s):

Sap Flow ◽

Cell Expansion ◽

Stem Growth ◽

Transport Processes ◽

Radial Transport ◽

Daily Growth ◽

Microscopic Scale ◽

Before And After ◽

Tree Stem

It is easy to measure annual growth of a tree stem. It is hard to measure its daily growth. The reason for this difficulty is the microscopic scale and the need to separate processes that simultaneously result in reversible and irreversible stem expansion. Here we present a model that separates reversible from irreversible cell expansion. Our model is novel, because it explains reversible expansion as consequence of longitudinally and, importantly, radially transmitted changes of hydraulic and osmotic pressures in xylem and bark. To capture and quantify these changes, we manipulated daily stem growth by applying a phloem girdle to stems of 9-m tall trees. The model was informed by measurements of radial movement in stem tissues and sap flow before and after and positions below and above the girdle. Additional measurements of whole-crown fluxes of H2O and CO2, leaf water potentials, non-structural carbohydrates and respiration were used to document the physiological impacts of girdling. This work sheds new light on the role of radial transport processes underpinning daily growth of tree stems. The model helps explain diel patterns of stem growth in trees.

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An Study of Influence of Imperfections on the Delamination of Diamond-Like Carbon Films

MRS Proceedings ◽

10.1557/proc-719-f8.36 ◽

2002 ◽

Vol 719 ◽

Author(s):

Myoung-Woon Moon ◽

Kyang-Ryel Lee ◽

Jin-Won Chung ◽

Kyu Hwan Oh

Keyword(s):

Cross Sections ◽

Focused Ion Beam ◽

Imaging System ◽

Ion Beam ◽

Carbon Films ◽

Diamond Like Carbon ◽

Glass Substrates ◽

Atomic Force ◽

Initiation And Propagation

AbstractThe role of imperfections on the initiation and propagation of interface delaminations in compressed thin films has been analyzed using experiments with diamond-like carbon (DLC) films deposited onto glass substrates. The surface topologies and interface separations have been characterized by using the Atomic Force Microscope (AFM) and the Focused Ion Beam (FIB) imaging system. The lengths and amplitudes of numerous imperfections have been measured by AFM and the interface separations characterized on cross sections made with the FIB. Chemical analysis of several sites, performed using Auger Electron Spectroscopy (AES), has revealed the origin of the imperfections. The incidence of buckles has been correlated with the imperfection length.

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Nanobiotechnology for Agriculture: Smart Technology for Combating Nutrient Deficiencies with Nanotoxicity Challenges

Sustainability ◽

10.3390/su13041781 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1781

Author(s):

Gaurav Chugh ◽

Kadambot H. M. Siddique ◽

Zakaria M. Solaiman

Keyword(s):

Targeted Delivery ◽

Plant Cells ◽

Agricultural Practices ◽

Nutrient Deficiencies ◽

Holistic View ◽

Synthesis Of Nanoparticles ◽

Toxicity Potential ◽

Stimulate Plant Growth ◽

Sustainable Agricultural Practices

Nanobiotechnology in agriculture is a driver for modern-day smart, efficient agricultural practices. Nanoparticles have been shown to stimulate plant growth and disease resistance. The goal of sustainable farming can be accomplished by developing and sustainably exploiting the fruits of nanobiotechnology to balance the advantages nanotechnology provides in tackling environmental challenges. This review aims to advance our understanding of nanobiotechnology in relevant areas, encourage interactions within the research community for broader application, and benefit society through innovation to realize sustainable agricultural practices. This review critically evaluates what is and is not known in the domain of nano-enabled agriculture. It provides a holistic view of the role of nanobiotechnology in multiple facets of agriculture, from the synthesis of nanoparticles to controlled and targeted delivery, uptake, translocation, recognition, interaction with plant cells, and the toxicity potential of nanoparticle complexes when presented to plant cells.

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Viroids as a Tool to Study RNA-Directed DNA Methylation in Plants

Cells ◽

10.3390/cells10051187 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1187

Author(s):

Michael Wassenegger ◽

Athanasios Dalakouras

Keyword(s):

Dna Methylation ◽

Rna Interference ◽

Gene Silencing ◽

Plant Cells ◽

Transcriptional Gene Silencing ◽

Rnai Machinery ◽

Double Stranded Rna ◽

Post Transcriptional Gene Silencing ◽

Cumulative Amount

Viroids are plant pathogenic, circular, non-coding, single-stranded RNAs (ssRNAs). Members of the Pospiviroidae family replicate in the nucleus of plant cells through double-stranded RNA (dsRNA) intermediates, thus triggering the host’s RNA interference (RNAi) machinery. In plants, the two RNAi pillars are Post-Transcriptional Gene Silencing (PTGS) and RNA-directed DNA Methylation (RdDM), and the latter has the potential to trigger Transcriptional Gene Silencing (TGS). Over the last three decades, the employment of viroid-based systems has immensely contributed to our understanding of both of these RNAi facets. In this review, we highlight the role of Pospiviroidae in the discovery of RdDM, expound the gradual elucidation through the years of the diverse array of RdDM’s mechanistic details and propose a revised RdDM model based on the cumulative amount of evidence from viroid and non-viroid systems.

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The Arabidopsis TETRATRICOPEPTIDE THIOREDOXIN-LIKE 1 Gene Is Involved in Anisotropic Root Growth during Osmotic Stress Adaptation

Genes ◽

10.3390/genes12020236 ◽

2021 ◽

Vol 12 (2) ◽

pp. 236

Author(s):

María Belén Cuadrado-Pedetti ◽

Inés Rauschert ◽

María Martha Sainz ◽

Vítor Amorim-Silva ◽

Miguel Angel Botella ◽

...

Keyword(s):

Osmotic Stress ◽

Root Growth ◽

Cell Walls ◽

Primary Root ◽

Stress Adaptation ◽

Elongation Zone ◽

Cortical Cells ◽

Force Microscopy ◽

Atomic Force ◽

The Mean

Mutations in the Arabidopsis TETRATRICOPEPTIDE THIOREDOXIN-LIKE 1 (TTL1) gene cause reduced tolerance to osmotic stress evidenced by an arrest in root growth and root swelling, which makes it an interesting model to explore how root growth is controlled under stress conditions. We found that osmotic stress reduced the growth rate of the primary root by inhibiting the cell elongation in the elongation zone followed by a reduction in the number of cortical cells in the proximal meristem. We then studied the stiffness of epidermal cell walls in the root elongation zone of ttl1 mutants under osmotic stress using atomic force microscopy. In plants grown in control conditions, the mean apparent elastic modulus was 448% higher for live Col-0 cell walls than for ttl1 (88.1 ± 2.8 vs. 16.08 ± 6.9 kPa). Seven days of osmotic stress caused an increase in the stiffness in the cell wall of the cells from the elongation zone of 87% and 84% for Col-0 and ttl1, respectively. These findings suggest that TTL1 may play a role controlling cell expansion orientation during root growth, necessary for osmotic stress adaptation.

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