Trends in Plant Science
SpotlightPectin Drives Cell Wall Morphogenesis without Turgor Pressure
Section snippets
Plants Have an Intricate Cell Wall with Diverse Functions
The cell wall is the rigid and semipermeable biphasic outer layer of plant cells. It is an essential component of plant cells and represents the major difference between plant and animal cells (animal cells lack a cell wall). In addition to its major function as a framework for the cell to prevent overexpansion, the plant cell wall (i) controls and directs cell growth, (ii) provides mechanical support and strength for the plant, (iii) mediates cell communication, (iv) plays a significant role
Nanofilament Structure of Pectin Homogalacturonan
Pectins constitute a diverse class of polysaccharides characterized by 1,4-linked α-D-galactosyluronic acid (GalpA, also known as galacturonic acid), including homogalacturonan (HG), xylogalacturonan (XGA), apiogalacturonan, rhamnogalacturonan I (RGI), and rhamnogalacturonan II (RGII). The ratios of these pectins is variable. HG (60%) is the most abundant, followed by RGI, and together these two classes constitute >75% of total pectins [4]. Pectins in the extracellular matrix were previously
Demethylation-Mediated Pectin Nanofilament Inflation Drives Plant Cell Anisotropic Growth without Turgor Pressure
Pectin methylation and demethylation play important roles in pectin structure and function. Pectin is biosynthesized in a methylated form in Golgi vesicles, and is generally converted into the demethylated form on insertion into the cell wall [6]. To study the behavior of methylated and demethylated HG, and their impact on cell wall shape and cell growth, Haas and colleagues first generated transgenic arabidopsis plants overexpressing either PECTIN METHYLESTERASE (PME) or PECTIN METHYLESTERASE
Concluding Remarks and Future Perspectives
This is the first observation that pectin forms nanofilament structures in intact cells. Based on the observation and their FEM model, Haas et al. demonstrate that HG methylation and demethylation result in switching of quaternary structures of HG nanofilaments, from a hexagonal to a rectangular lattice in the cell wall, leading to HG filament expansion, and that this is the primary force that shapes the cell wall and cell growth (Figure 1B) [3]. However, there are still many questions to be
Acknowledgments
We greatly appreciate Dr Claudia Jolls for her excellent comments and for proofreading this paper. D.Z. is supported by the National Natural Science Foundation of China (31172257), the Science Research Project in Henan Province of China (192102110174), and the Talent Project of Henan Agriculture University. B.Z. is supported in part by Cotton Incorporated and the National Science Foundation (award 1658709).
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Gene-specific silencing of SlPL16, a pectate lyase coding gene, extends the shelf life of tomato fruit
2023, Postharvest Biology and TechnologyPostharvest control of Escherichia coli O157:H7 on romaine lettuce using a novel pelargonic acid sanitizer
2022, LWTCitation Excerpt :In the current study, leaves treated with Pel generally exhibited more skin elasticity compared to the other sanitizer treatments, with the exception of the NR rinse treatment. However, the NR treatment may be an inadequate baseline of skin elasticity because leaves did not undergo submersion in water or rinse treatment, therefore, it likely did not have comparable initial turgidity compared to leaves submerged in other treatment solutions (Vogler, Burri, Nelson, & Grossniklaus, 2020; Zhang & Zhang, 2020). The quantifiable increase in skin elasticity for Pel-treated leaves is likely indicative of the necrosis and foliar breakdown that is characteristic of Pel-containing herbicides (Lederer, Fujimori, Tsujino, Wakabayashi, & Böger, 2004).
Sculpting the surface: Structural patterning of plant epidermis
2021, iScienceCitation Excerpt :Pectin nanofilaments were seen oriented perpendicularly to the cell outer surface in the anticlinal walls of the pavement cells, but this organization was not found in the periclinal walls (Haas et al., 2020). This contrasts with previous studies that consider a physical connexion between both walls as major for cells morphogenesis (Bidhendi and Geitmann, 2019a, 2019b; Chebli et al., 2021; Cosgrove and Anderson, 2020; Zhang and Zhang, 2020). Haas and colleagues propose instead that de-esterification of pectin homogalacturonan nanofilaments could, by swelling, contribute to cell growth and shape formation independently from turgor pressure (Haas et al., 2020).
Mechanics of active gel spheres under bulk contraction
2021, International Journal of Mechanical SciencesCitation Excerpt :We wish to make some progress towards addressing this question. The present study focuses on a theory of active gels at the macroscale [12–15] and aims to understand the relationships between elasticity, activity and diffusion which drives liquid release and liquid migration that can be observed in active gels and in other macroscopic living systems where they also deliver stresses affecting the activity itself [16–19]. We use the perspective of continuum physics: an active gel is considered as a biphasic material consisting of an elastic polymer network bathed in an interstitial liquid.
Forces on and in the cell walls of living plants
2024, Scientific Journal of Silesian University of Technology. Series Transport