Metal-Nano-Ink Coating for Monitoring and Quantification of Cotyledon Epidermal Cell Morphogenesis

During cotyledon growth, the pavement cells, which make up most of the epidermal layer, undergo dynamic morphological changes from simple to jigsaw puzzle-like shapes in most dicotyledonous plants. Morphological analysis of cell shapes generally involves the segmentation of cells from input images followed by the extraction of shape descriptors that can be used to assess cell shape. Traditionally, replica and fluorescent labeling methods have been used for time-lapse observation of cotyledon epidermal cell morphogenesis, but these methods require expensive microscopes and can be technically demanding. Here, we propose a silver-nano-ink coating method for time-lapse imaging and quantification of morphological changes in the epidermal cells of growing Arabidopsis thaliana cotyledons. To obtain high-resolution and wide-area cotyledon surface images, we placed the seedlings on a biaxial goniometer and adjusted the cotyledons, which were coated by dropping silver ink onto them, to be as horizontal to the focal plane as possible. The omnifocal images that had the most epidermal cell shapes in the observation area were taken at multiple points to cover the whole surface area of the cotyledon. The multi-point omnifocal images were automatically stitched, and the epidermal cells were automatically and accurately segmented by machine learning. Quantification of cell morphological features based on the segmented images demonstrated that the proposed method could quantitatively evaluate jigsaw puzzle-shaped cell growth and morphogenesis. The method was successfully applied to phenotyping of the bpp125 triple mutant, which has defective pavement cell morphogenesis. The proposed method will be useful for time-lapse non-destructive phenotyping of plant surface structures and is easier to use than the conversional methods that require fluorescent dye labeling or transformation with marker gene constructs and expensive microscopes such as the confocal laser microscope.

Download Full-text

Pigment Distribution and Epidermal Cell Shape in Dendrobium Species and Hybrids

HortScience ◽

10.21273/hortsci.38.4.573 ◽

2003 ◽

Vol 38 (4) ◽

pp. 573-577 ◽

Cited By ~ 14

Author(s):

Rasika G. Mudalige ◽

Adelheid R. Kuehnle ◽

Teresita D. Amore

Keyword(s):

Epidermal Cell ◽

Cell Shape ◽

Epidermal Cells ◽

Vascular Bundles ◽

Color Intensity ◽

Visual Texture ◽

Intensity Perception ◽

Cell Layers ◽

Cell Shapes ◽

Pigment Distribution

Perianths of 34 Dendrobium Sw. species and hybrids were examined to elucidate the roles of pigment distribution and shape of upper epidermal cells in determining color intensity, perception, and visual texture. Color intensity was determined by the spatial localization of anthocyanin in tissue layers, i.e., in the epidermal, subepidermal, and mesophyll layers, as well as by distribution of pigmented cells within the tissue layer. Anthocyanins were confined to the epidermal layer or subepidermal layer in flowers with low color intensity, whereas they were also in several layers of mesophyll in more intensely colored flowers. Striped patterns on the perianth were due to the restriction of pigment to cells surrounding the vascular bundles. Color perception is influenced by the presence or absence of carotenoids, which when present, were distributed in all cell layers. Anthocyanins in combination with carotenoids resulted in a variety of flower colors ranging from red, maroon, bronze to brown, depending on the relative location of the two pigments. Four types of epidermal cell shapes were identified in Dendrobium flowers: flat, dome, elongated dome, and papillate. Epidermal cell shape and cell packing in the mesophyll affected the visual texture. Petals and sepals with flat cells and a tightly packed mesophyll had a glossy texture, whereas dome cells and loosely packed mesophyll contributed a velvety texture. The labella in the majority of flowers examined had a complex epidermis with more than one epidermal cell shape, predominantly papillate epidermal cells.

Download Full-text

Solving the Puzzle of Shape Regulation in Plant Epidermal Pavement Cells

Annual Review of Plant Biology ◽

10.1146/annurev-arplant-080720-081920 ◽

2021 ◽

Vol 72 (1) ◽

pp. 525-550

Author(s):

Sijia Liu ◽

François Jobert ◽

Zahra Rahneshan ◽

Siamsa M. Doyle ◽

Stéphanie Robert

Keyword(s):

Cell Wall ◽

Cell Shape ◽

Current Knowledge ◽

Regulatory Proteins ◽

Jigsaw Puzzle ◽

Environment Protection ◽

Cell Morphogenesis ◽

Pavement Cell ◽

Pavement Cells ◽

Organ Growth

The plant epidermis serves many essential functions, including interactions with the environment, protection, mechanical strength, and regulation of tissue and organ growth. To achieve these functions, specialized epidermal cells develop into particular shapes. These include the intriguing interdigitated jigsaw puzzle shape of cotyledon and leaf pavement cells seen in many species, the precise functions of which remain rather obscure. Although pavement cell shape regulation is complex and still a long way from being fully understood, the roles of the cell wall, mechanical stresses, cytoskeleton, cytoskeletal regulatory proteins, and phytohormones are becoming clearer. Here, we provide a review of this current knowledge of pavement cell morphogenesis, generated from a wealth of experimental evidence and assisted by computational modeling approaches. We also discuss the evolution and potential functions of pavement cell interdigitation. Throughout the review, we highlight some of the thought-provoking controversies and creative theories surrounding the formation of the curious puzzle shape of these cells.

Download Full-text

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.

Download Full-text

Morphological Changes in Epidermal Cells of Fish with Chronic Anosmia and Enucleation

Journal of Ichthyology ◽

10.1134/s0032945221050027 ◽

2021 ◽

Vol 61 (5) ◽

pp. 764-770

Author(s):

G. V. Devitsina

Keyword(s):

Morphological Changes ◽

Epidermal Cells ◽

Chronic Anosmia

Download Full-text

Contact behaviour during the reassociation of dissociated epithelial cells in primary culture

Journal of Cell Science ◽

10.1242/jcs.88.4.521 ◽

1987 ◽

Vol 88 (4) ◽

pp. 521-526

Author(s):

R.M. Brown ◽

C.A. Middleton

Keyword(s):

Epithelial Cells ◽

Chick Embryo ◽

Primary Culture ◽

Cell Cultures ◽

Corneal Epithelium ◽

Time Lapse ◽

Cell Types ◽

Epidermal Cells ◽

Isolated Cells ◽

Contact Behaviour

The behaviour in culture of dissociated epithelial cells from chick embryo pigmented retina epithelium (PRE), corneal epithelium (CE) and epidermis has been studied using time-lapse cinematography. The analysis concentrated on the contact behaviour of 60 previously isolated cells of each type during a 24 h period starting 3.5 h after the cells were plated out. During the period analysed the number of isolated cells in cultures of all three types gradually decreased as they became incorporated into islands and sheets of cells. However, there were significant differences in behaviour between the cell types during the establishment of these sheets and islands. In PRE cell cultures, islands of cells developed because, throughout the period of analysis, collisions involving previously isolated cells almost invariably resulted in the development of a stable contact. Once having established contact with another cell these cells rarely broke away again to become reisolated. In contrast the contacts formed between colliding CE and epidermal cells were, at least initially, much less stable and cells of both these types were frequently seen to break away and become reisolated after colliding with other cells. Sheets and islands of cells eventually developed in these cultures because the frequency with which isolated cells become reisolated decreased with increasing time in culture. The possible reasons underlying the different behaviour of PRE cells, when compared with that of CE and epidermal cells, are discussed. It is suggested that the decreasing tendency of isolated CE and epidermal cells to become reisolated may be related to the formation of desmosomes.

Download Full-text

Multiple mechanisms of dissociated epidermal cell spreading.

The Journal of Cell Biology ◽

10.1083/jcb.96.1.63 ◽

1983 ◽

Vol 96 (1) ◽

pp. 63-67 ◽

Cited By ~ 60

Author(s):

K S Stenn ◽

J A Madri ◽

T Tinghitella ◽

V P Terranova

Keyword(s):

Serum Albumin ◽

Epidermal Cell ◽

Type Iv Collagen ◽

Cell Spreading ◽

Specific Protein ◽

Epidermal Cells ◽

Type Iv ◽

Basement Membrane Protein ◽

Specific Proteins

To test the possibility that epidermal cells use a common basement membrane protein whenever they spread, in vitro experiments were conducted using trypsin-dissociated guinea pig epidermal cells and the following proteins: human serum, bovine serum albumin, serum fibronectin, Type IV collagen, laminin, and epibolin (a recently described serum glycoprotein which supports epidermal cell spreading; Stenn, K.S., 1981, Proc. Natl. Acad. Sci. U.S.A. 78:6907.). When the cells were added to media containing the specific proteins, all the tested proteins, except for serum albumin, supported cell spreading. Added to protein-coated substrates in defined media, the cells spread on fibronectin, epibolin, and laminin-Type IV collagen, but not on albumin or whole serum. In none of these experiments were the results qualitatively affected by the presence of cycloheximide. Antibodies to a specific protein blocked cell spreading on that protein but not on the other active proteins, e.g. whereas antibodies to epibolin blocked cell spreading on epibolin, they did not affect spreading on fibronectin, collagen, or laminin. In a second assay in which the cells were allowed to adhere to tissue culture plastic before the protein-containing medium was added, the cells spread only if the medium contained epibolin. Moreover, under these conditions the spreading activity of whole serum and plasma was neutralized by antiepibolin antibodies. These results support the conclusion that dissociated epidermal cells possess multiple spreading modes which depend, in part, on the proteins of the substrate, proteins of the medium, and the sequence of cell adhesion and protein exposure.

Download Full-text

Cuticular reticulation replicates the pattern of epidermal cells in lowermost Cambrian scalidophoran worms

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.0470 ◽

2020 ◽

Vol 287 (1926) ◽

pp. 20200470

Author(s):

Deng Wang ◽

Jean Vannier ◽

Xiao-guang Yang ◽

Jie Sun ◽

Yi-fei Sun ◽

...

Keyword(s):

Epidermal Cell ◽

Mechanical Response ◽

Sedimentary Environment ◽

Epidermal Cells ◽

Early Cambrian ◽

Extracellular Material ◽

Cuticle Formation ◽

Stem Group ◽

The Relationship

The cuticle of ecdysozoans (Panarthropoda, Scalidophora, Nematoida) is secreted by underlying epidermal cells and renewed via ecdysis. We explore here the relationship between epidermis and external cuticular ornament in stem-group scalidophorans from the early Cambrian of China (Kuanchuanpu Formation; ca 535 Ma) that had two types of microscopic polygonal cuticular networks with either straight or microfolded boundaries. Detailed comparisons with modern scalidophorans (priapulids) indicate that these networks faithfully replicate the cell boundaries of the epidermis. This suggests that the cuticle of early scalidophorans formed through the fusion between patches of extracellular material secreted by epidermal cells, as observed in various groups of present-day ecdysozoans, including arthropods. Key genetic, biochemical and mechanical processes associated with ecdysis and cuticle formation seem to have appeared very early (at least not later than 535 Ma) in the evolution of ecdysozoans. Microfolded reticulation is likely to be a mechanical response to absorbing contraction exerted by underlying muscles. The polygonal reticulation in early and extant ecdysozoans is clearly a by-product of the epidermal cell pavement and interacted with the sedimentary environment.

Download Full-text

The mechanism of K cell (antibody-dependent) cell mediated cytotoxicity II. Characteristics of the effector cell and morphological changes in the target cell

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1977.0078 ◽

1977 ◽

Vol 197 (1129) ◽

pp. 417-424 ◽

Cited By ~ 11

Keyword(s):

T Cells ◽

Cell Death ◽

Target Cell ◽

Morphological Changes ◽

Cytotoxic T Cells ◽

Time Lapse ◽

Physical Characteristics ◽

Cell Contact ◽

Cell Cytotoxicity ◽

K Cells

K cells share certain physical characteristics with T cells. This has made it possible to apply standard cell purification techniques to be used for the enrichment of K cells. This has in turn enabled time lapse studies to be carried out at low cell density. In addition, to the similar physical characteristics, K cells have a structure and movement similar to those of cytotoxic T cells. K cell cytotoxicity does no apparent damage to the K cell and each K cell is able to kill more than one target cell. Analysis of time lapse films of cytotoxicity of mouse P815 mastocytoma cells directly confirms three inferences on the mechanism of target cell death suggested by the kinetic data in the previous paper: contact itself does not appear to damage the target cell; target cell death usually begins within 15 min of K cell contact; cell death is an explosive event with zeiosis ‘boiling' of the cytoplasm. This phenomenon is similar to that observed with T cell cytotoxicity and quite different to changes seen during lysis by antibody and complement. Analysis of films of cytotoxicity of human MRC5 cells which are glass adherent has shown that the K cell is in close apposition to the nucleus within 1 min of the first cytoplasmic changes (shrinkage).

Download Full-text

The Metamorphosis of Insects: Tercentenary Lecture delivered by Professor V. B. Wigglesworth, F. R. S., at 10.15 a.m. on Saturday 23 July 1960 at the Royal College of Surgeons

Notes and Records the Royal Society journal of the history of science ◽

10.1098/rsnr.1961.0016 ◽

1961 ◽

Vol 16 (1) ◽

pp. 81-84 ◽

Cited By ~ 1

Keyword(s):

Epidermal Cell ◽

Royal College ◽

Single Layer ◽

Secretory Activity ◽

Epidermal Cells ◽

Social Functions ◽

Outer Skin ◽

The Subject ◽

Growth Changes

THE visible form of the insect is defined by the outer skin or cuticle. The cuticle is the product of the single layer of epidermal cells which lie beneath it. The form of the insect is thus determined by the growth changes and the secretory activity of the epidermal cell. The purpose of the lecture was to approach the subject of metamorphosis through a consideration of the physiology of the epidermal cell. The epidermal cell is interesting because it combines within itself so many functions, actual and potential; social functions as a member of the community of cells of which it forms a part, and individual functions where it is concerned primarily with its own affairs.

Download Full-text