Roles of the plasma membrane and the cell wall in the responses of plant cells to freezing

Despite a variety of shapes and sizes, the generic mechanical structure of cells is remarkably similar from one cell type to the next. All cells are bounded by a plasma membrane, a fluid sheet that controls the passage of materials into and out of the cell. Plant cells and bacteria reinforce this membrane with a cell wall, permitting the cell to operate at an elevated osmotic pressure. Simple cells, such as the bacterium shown in Figure 1a, possess a fairly homogeneous interior containing the cell's genetic blueprint and protein workhorses, but no mechanical elements. In contrast, as can be seen in Figure 1b, plant and animal cells contain internal compartments and a filamentous cytoskeleton—a network of biological ropes, cables, and poles that helps maintain the cell's shape and organize its contents.Four principal types of filaments are found in the cytoskeleton: spectrin, actin, microtubules, and a family of intermediate filaments. Not all filaments are present in all cells. The chemical composition of the filaments shows only limited variation from one cell to another, even in organisms as diverse as humans and yeasts. Membranes have a more variable composition, consisting of a bi-layer of dual-chain lipid molecules in which are embedded various proteins and frequently a moderate concentration of cholesterol. The similarity of the cell's mechanical elements in chemical composition and physical characteristics encourages us to search for universal strategies that have developed in nature for the engineering specifications of the cell. In this article, we concentrate on the cytoskeleton and its filaments.

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Structure and development of cortical microtubule arrays in plant cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082182 ◽

1978 ◽

Vol 36 (2) ◽

pp. 264-265

Author(s):

A.R. Hardham ◽

B.E.S. Gunning

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Cortical Microtubule ◽

Plant Cells ◽

Original Description ◽

Cell Cortex ◽

Cortical Microtubules ◽

Fundamental Part ◽

Cellulose Component

Microtubules in the plant cell cortex are usually aligned parallel to microfibrils of cellulose that are being deposited in the cell wall, and are considered to function in guiding or orienting cellulose synthetase complexes that lie in or on the plasma membrane. The cellulose component is largely responsible for the mechanical reaction of the wall to turgor forces, thereby determining cell size and shape, and therefore the role of the cortical microtubules is a fundamental part of the overall morphogenetic process in plants. It is important to determine the structure of cortical arrays of microtubules and to learn how the cell regulates their development, neither of these aspects having been investigated adequately since the original description likened the microtubules to “hundreds of hoops around the cell”.

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Intercellular trafficking via plasmodesmata: molecular layers of complexity

Cellular and Molecular Life Sciences ◽

10.1007/s00018-020-03622-8 ◽

2020 ◽

Cited By ~ 1

Author(s):

Ziqiang Patrick Li ◽

Andrea Paterlini ◽

Marie Glavier ◽

Emmanuelle M. Bayer

Keyword(s):

Endoplasmic Reticulum ◽

Cell Wall ◽

Plasma Membrane ◽

Plant Cells ◽

Functional Domains ◽

Dynamic Interactions ◽

Intercellular Trafficking ◽

Multiple Routes ◽

Molecular Components ◽

Molecular Layers

Abstract Plasmodesmata are intercellular pores connecting together most plant cells. These structures consist of a central constricted form of the endoplasmic reticulum, encircled by some cytoplasmic space, in turn delimited by the plasma membrane, itself ultimately surrounded by the cell wall. The presence and structure of plasmodesmata create multiple routes for intercellular trafficking of a large spectrum of molecules (encompassing RNAs, proteins, hormones and metabolites) and also enable local signalling events. Movement across plasmodesmata is finely controlled in order to balance processes requiring communication with those necessitating symplastic isolation. Here, we describe the identities and roles of the molecular components (specific sets of lipids, proteins and wall polysaccharides) that shape and define plasmodesmata structural and functional domains. We highlight the extensive and dynamic interactions that exist between the plasma/endoplasmic reticulum membranes, cytoplasm and cell wall domains, binding them together to effectively define plasmodesmata shapes and purposes.

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Hechtian Strands Transmit Cell Wall Integrity Signals in Plant Cells

Plants ◽

10.3390/plants9050604 ◽

2020 ◽

Vol 9 (5) ◽

pp. 604

Author(s):

Arata Yoneda ◽

Misato Ohtani ◽

Daisuke Katagiri ◽

Yoichiroh Hosokawa ◽

Taku Demura

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Femtosecond Laser ◽

Cell Morphology ◽

Laser Microdissection ◽

Plant Cells ◽

Laser Pulses ◽

Femtosecond Laser Pulses ◽

Cell Wall Integrity ◽

Calcofluor White

Hechtian strands are thread-like structures in plasmolyzed plant cells that connect the cell wall to the plasma membrane. Although these strands were first observed more than 100 years ago, their physiological roles are largely unknown. Here, we used intracellular laser microdissection to examine the effects of disrupting Hechtian strands on plasmolyzed tobacco BY-2 cells. When we focused femtosecond laser pulses on Hechtian strands, targeted disruptions were induced, but no visible changes in cell morphology were detected. However, the calcofluor white signals from β-glucans was detected in plasmolyzed cells with disrupted Hechtian strands, whereas no signals were detected in untreated plasmolyzed cells. These results suggest that Hechtian strands play roles in sensing cell wall integrity.

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Multivesicular structures and cell wall growth

Canadian Journal of Botany ◽

10.1139/b69-275 ◽

1969 ◽

Vol 47 (12) ◽

pp. 1873-1877 ◽

Cited By ~ 25

Author(s):

L. C. Fowke ◽

George Setterfield

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Physiological State ◽

Plant Cells ◽

Wall Material ◽

Golgi Bodies ◽

Wall Growth ◽

Cell Wall Deposition ◽

Applied Auxin ◽

In Cells

Applied auxin caused cells of artichoke tuber slices to expand and deposit significant amounts of new wall material while cells in slices held on water remained essentially inert in both respects. Cells in all physiological treatments showed multivesicular structures at the plasma membrane (plasmalemmasomes, lomasomes), within the cytoplasm and within the central vacuoles. The number of plasmalemmasomes was considerably greater in cells not depositing wall than in cells treated with auxin to stimulate wall synthesis. Multivesicular structures showed no relation to Golgi bodies, which increase in number and apparent activity in response to auxin treatment. It is concluded that plasmalemmasomes are not involved in cell wall deposition. Multivesicular structures in plant cells could have several origins and it is suggested that some may represent artifactual reorganization of plasmalemma and tonoplast membranes during cytological processing. Such reorganization would presumably be sensitive to the physiological state of the tissue.

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Effect of a host-specific toxin (AM-toxin I) produced by Alternaria mali, an apple pathogen, on the ultrastructure of plasma membrane of cells in apple and Japanese pear leaves

Canadian Journal of Botany ◽

10.1139/b77-271 ◽

1977 ◽

Vol 55 (18) ◽

pp. 2383-2393 ◽

Cited By ~ 24

Author(s):

Pyoyun Park ◽

Mitsuya Tsuda ◽

Yoshiharu Hayashi ◽

Tamio Ueno

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Plasma Membranes ◽

Plant Cells ◽

Host Cells ◽

Japanese Pear ◽

Susceptible Plant ◽

Secondary Effects ◽

Permeability Changes ◽

Ultrastructural Modifications

AM-toxin I (4 μg/ml), a host-specific toxin of Alternaria mali, caused permeability changes in susceptible apple and Nijisseiki pear leaves within 5 min of treatment. The first effect of the toxin appeared on plasma membranes of susceptible apple cells. One hour after toxin treatment, slight invaginations were evident in plasma membranes near plasmodesmata. Six hours after treatment, the spaces between cell wall and invaginated plasma membrane contained lomasome-like vesicles, membranous fragments, and desmotubules extending from plasmodesmata. The membranous materials appeared to originate from the plasma membrane. Thirty-one hours after treatment, necrotic cells of susceptible leaves showed the general disruptions of cellular membranes which might be caused by secondary effects of the toxin. The similar changes of plasma membrane and plasmodesmata also were found in Nijisseiki pear cells treated with AM-toxin I (4 μg/ml) for 1 h and 6 h. The invaginations of the plasma membrane at plasmodesmata were the first ultrastructural modifications in the toxin-treated Nijisseiki cells. AM-toxin I did not affect the ultrastructure of resistant apple and Chojuro pear cells. These results indicate that the initial sites for the toxin may be on the plasma membrane of the susceptible apple cells. Furthermore, the results suggest that the plasma membrane modifications are associated with permeability changes in the toxin-treated, susceptible plant cells except for original host cells treated with the toxin.

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Immunogold-labelling localization of chlorophyllase at different developmental stages of Pachira macrocarpa leaves

10.21203/rs.3.rs-362210/v1 ◽

2021 ◽

Author(s):

Tzan-Chain Lee ◽

Kuan-Hung Lin ◽

Chang-Chang Chen ◽

Tin-Han Shih ◽

Meng-Yuan Huang ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Cell Wall ◽

Plasma Membrane ◽

Thylakoid Membrane ◽

Developmental Stages ◽

Higher Plants ◽

Plant Cells ◽

Immunogold Labelling ◽

Transmission Electron

Abstract Background: Chlorophyllases (Chlases) are housekeeping proteins in plant cells. The dephytylating enzymes can catalyze chlorophyll (Chl) to form chlorophyllide, but the distribution of Chlases in plant cells is still an interesting debate. In this study, antibody of PmCLH2 was made and used by immunogold-labelling technique to detect the location of Chlase of Pachira macrocarpa (Pm) leaves at four developmental stages, including young, mature, yellowing, and senesced stages. Results: The transmission electron microscopy results show that Chlases were comprehensively found in portions of chloroplast, such as the inner membrane of the envelope, grana, and the thylakoid membrane of the chloroplast, cytosol, and vacuoles at young, mature, and yellowing stages of Pm leaves, but not in the cell wall, plasma membrane, mitochondria, and nucleus. Conclusions: PmChlases were mainly detected in vacuoles at the senescent stage, but a few were found in the chloroplasts. A pathway is proposed to explain the birth and death of Chl, Chlase, and chloroplasts in higher plants.

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The structure of plasmodesmata as revealed by plasmolysis, detergent extraction, and protease digestion.

The Journal of Cell Biology ◽

10.1083/jcb.112.4.739 ◽

1991 ◽

Vol 112 (4) ◽

pp. 739-747 ◽

Cited By ~ 80

Author(s):

L G Tilney ◽

T J Cooke ◽

P S Connelly ◽

M S Tilney

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Cell Walls ◽

Plant Cells ◽

Intercellular Bridges ◽

Protease Digestion ◽

Onoclea Sensibilis ◽

Detergent Extraction ◽

Triton X ◽

Cut Surface

Plasmodesmata or intercellular bridges that connect plant cells are cylindrical channels approximately 40 nm in diameter. Running through the center of each is a dense rod, the desmotubule, that is connected to the endoplasmic reticulum of adjacent cells. Fern, Onoclea sensibilis, gametophytes were cut in half and the cut surfaces exposed to the detergent, Triton X 100, then fixed. Although the plasma membrane limiting the plasmodesma is solubilized partially or completely, the desmotubule remains intact. Alternatively, if the cut surface is exposed to papain, then fixed, the desmotubule disappears, but the plasma membrane limiting the plasmodesmata remains intact albeit swollen and irregular in profile. Gametophytes were plasmolyzed, and then fixed. As the cells retract from their cell walls they leave behind the plasmodesmata still inserted in the cell wall. They can break cleanly when the cell proper retracts or can pull away portions of the plasma membrane of the cell with them. Where the desmotubule remains intact, the plasmodesma retains its shape. These images and the results with detergents and proteases indicate that the desmotubule provides a cytoskeletal element for each plasmodesma, an element that not only stabilizes the whole structure, but also limits its size and porosity. It is likely to be composed in large part of protein. Suggestions are made as to why this structure has been selected for in evolution.

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