Cell Wall Composition and Structure Define the Developmental Fate of Embryogenic Microspores in Brassica napus

Microspore cultures generate a heterogeneous population of embryogenic structures that can be grouped into highly embryogenic structures [exine-enclosed (EE) and loose bicellular structures (LBS)] and barely embryogenic structures [compact callus (CC) and loose callus (LC) structures]. Little is known about the factors behind these different responses. In this study we performed a comparative analysis of the composition and architecture of the cell walls of each structure by confocal and quantitative electron microscopy. Each structure presented specific cell wall characteristics that defined their developmental fate. EE and LBS structures, which are responsible for most of the viable embryos, showed a specific profile with thin walls rich in arabinogalactan proteins (AGPs), highly and low methyl-esterified pectin and callose, and a callose-rich subintinal layer not necessarily thick, but with a remarkably high callose concentration. The different profiles of EE and LBS walls support the development as suspensorless and suspensor-bearing embryos, respectively. Conversely, less viable embryogenic structures (LC) presented the thickest walls and the lowest values for almost all of the studied cell wall components. These cell wall properties would be the less favorable for cell proliferation and embryo progression. High levels of highly methyl-esterified pectin are necessary for wall flexibility and growth of highly embryogenic structures. AGPs seem to play a role in cell wall stiffness, possibly due to their putative role as calcium capacitors, explaining the positive relationship between embryogenic potential and calcium levels.

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Histochemical techniques in plant science: more than meets the eye

Plant and Cell Physiology ◽

10.1093/pcp/pcab022 ◽

2021 ◽

Author(s):

Vaishali Yadav ◽

Namira Arif ◽

Vijay Pratap Singh ◽

Gea Guerriero ◽

Roberto Berni ◽

...

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Histochemical Staining ◽

Cellular Level ◽

Plant Science ◽

Specific Cell ◽

Environmental Constraints ◽

Cell Wall Components ◽

Cell Structures ◽

Wall Components

Abstract Histochemistry is an essential analytical tool interfacing extensively with plant science. The literature is indeed constellated with examples showing its use to decipher specific physiological and developmental processes, as well as to study plant cell structures. Plant cell structures are translucent unless they are stained. Histochemistry allows the identification and localization, at the cellular level, of biomolecules and organelles in different types of cells and tissues, based on the use of specific staining reactions and imaging. Histochemical techniques are also widely used for the in-vivo localization of promoters in specific tissues, as well as to identify specific cell wall components such as lignin and polysaccharides. Histochemistry also enables the study of plants’ reactions to environmental constraints, for example, the production of reactive oxygen species (ROS) can be traced by applying histochemical staining techniques. The possibility of detecting ROS and localizing them at the cellular level is vital in establishing the mechanisms involved in the sensitivity and tolerance to different stress conditions in plants. This review comprehensively highlights the additional value of histochemistry as a complementary technique to high-throughput approaches for the study of the plant response to environmental constraints. Moreover, here we have provided and extensive survey of the available plant histochemical staining methods used for the localization of metals, minerals, secondary metabolites, cell wall components, as well as the detection of ROS production in plant cells. The use of recent technological advances like CRISPR/Cas9 based genome-editing for histological application is also addressed. This review also surveys the availale literature data on histochemical techniques used to study the response of plants to abiotic stresses and to identify the effects at the tissue and cell-level.

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Comparison of Cell Wall Components in Normal and Disordered Juice Vesicles of Grapefruit

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.115.2.281 ◽

1990 ◽

Vol 115 (2) ◽

pp. 281-287 ◽

Cited By ~ 14

Author(s):

Yong-Soo Hwang ◽

D.J. Huber ◽

L.G. Albrigo

Keyword(s):

Molecular Weight ◽

Cell Wall ◽

Ion Exchange ◽

Gel Filtration ◽

Cell Wall Composition ◽

Water Soluble ◽

Citrus Paradisi ◽

Composition And Structure ◽

The Difference ◽

Wall Components

Cell wall composition and structure were examined in visually normal (N), granulated (G), and collapsed (VC) juice vesicles of `Marsh Seedless' grapefruit (Citrus paradisi) Macf.). According to gel-filtration data, VC appeared to be associated with a modification of water-soluble (WSP) and chelate-soluble (CSP) pectin molecular weight (Mr); small-Mr pectins increased, whereas large-J4. pectins decreased. The difference in M= of pectins did not appear to be mediated by polygalacturonases. Molecular weight of hemicelluloses did not differ. Granulated vesicles contained about two times more structural polysaccharides (pectins, hemicelhdose, and cellulose) than N vesicles, although hemicellulose and pectin M= modification were absent. Ion-exchange profiles of WSP, CSP, and hemicelhrlose fractions of VC and G vesicles were not different from those of N vesicles. Individual cells in vesicles with G and these vesicles themselves were much larger than those of N vesicles, whereas cells in VC were partially or completely collapsed.

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Expansin-controlled cell wall stiffness regulates root growth in Arabidopsis

10.1101/2020.06.25.170969 ◽

2020 ◽

Author(s):

Marketa Samalova ◽

Kareem Elsayad ◽

Alesia Melnikava ◽

Alexis Peaucelle ◽

Evelina Gahurova ◽

...

Keyword(s):

Cell Wall ◽

Root Growth ◽

Cell Types ◽

Root Apical Meristem ◽

Specific Cell ◽

Wall Stiffness ◽

Specific Localization ◽

Dependent Cell ◽

Cell Type Specific

ABSTRACTExpansins facilitate cell expansion via mediating pH-dependent cell wall (CW) loosening. However, the role of expansins in the control of biomechanical CW properties in the tissue and organ context remains elusive. We determined hormonal responsiveness and specificity of expression and localization of expansins predicted to be direct targets of cytokinin signalling. We found EXPA1 homogenously distributed throughout the CW of columella/ lateral root cap, while EXPA10 and EXPA14 localized predominantly at the three-cell boundaries of epidermis/cortex in various root zones. Cell type-specific localization of EXPA15 overlaps with higher CW stiffness measured via Brillouin light scattering microscopy. As indicated by both Brillouin frequency shift and AFM-measured Young’s modulus, EXPA1 overexpression upregulated CW stiffness, associated with shortening of the root apical meristem and root growth arrest. We propose that root growth in Arabidopsis requires delicate orchestration of biomechanical CW properties via tight regulation of various expansins’ localization to specific cell types and extracellular domains.

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Xyloglucan homeostasis and microtubule dynamics synergistically maintain meristem geometry and robustness of phyllotaxis in Arabidopsis

10.1101/607481 ◽

2019 ◽

Cited By ~ 1

Author(s):

Feng Zhao ◽

Wenqian Chen ◽

Julien Sechet ◽

Marjolaine Martin ◽

Simone Bovio ◽

...

Keyword(s):

Cell Wall ◽

Biochemical Analysis ◽

Methylation Status ◽

Active Role ◽

Cellulose Content ◽

Wall Stiffness ◽

Micro Indentation ◽

Precise Role ◽

Wall Components

ABSTRACTThe shoot apical meristem (SAM) gives rise to all aerial organs of the plant. The cell walls are supposed to play a central role in this process, translating molecular regulation into dynamic changes of growth rates and directions, although their precise role in morphogenesis during organ formation remains not well understood. Here we investigate the role of xyloglucans (XyGs), which form a major, yet functionally poorly characterized, wall component in the SAM. Using immunolabeling, biochemical analysis, genetic approaches, micro-indentation, laser ablations and live imaging, we show that XyGs are important for meristem shape and phyllotaxis, although no difference in cell wall stiffness could be observed when XyGs are perturbed. Mutations in enzymes required for XyG synthesis also affect other cell wall components such as cellulose content and the pectin methylation status. Interestingly, we show that the control of cortical microtubules dynamics by the severing enzyme KATANIN becomes vital when XyGs are perturbed or absent. This suggests an active role of the cytoskeleton in compensating for altered wall composition.

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The SYP123-VAMP727 SNARE complex is involved in the delivery of inner cell wall components to the root hair shank in Arabidopsis

10.1101/2020.12.28.424500 ◽

2020 ◽

Author(s):

Tomoko Hirano ◽

Kazuo Ebine ◽

Takashi Ueda ◽

Takumi Higaki ◽

Takahiro Nakayama ◽

...

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Root Hair ◽

Cortical Microtubule ◽

Root Hairs ◽

Snare Complex ◽

Cell Wall Components ◽

Root Hair Cell ◽

Wall Stiffness ◽

Wall Components

AbstractA root hair is a long tubular protrusion from a root hair cell established via tip growth, which is accomplished by the polarized deposition of membranous and cell wall components at the root hair apex accompanied by simultaneous hardening of the shank. The polarized secretion of materials to the root hair apex is well investigated; however, little is known about the deposition of inner cell wall materials at the root hair shank. We have previously reported that phosphatidylinositol-3,5-bisphosphate (PtdIns(3,5)P2)/ROP10 signaling is required for the regulation of cortical microtubule construction and the deposition of inner cell wall components at the root hair shank during hardening. To unravel the alternate secretion mechanism for delivery of the inner cell wall components to root hair shank, here, we demonstrate that root hair-specific Qa-SNARE, SYP123, localizes to the subapical zone and shank of elongating root hairs in Arabidopsis. SYP123-mediated root hair elongation was inhibited by the FAB1 inhibitor YM201636, and inhibition of PtdIns(3,5)P2 production impaired the plasma membrane localization of SYP123. We also showed that SYP123 forms a SNARE complex with VAMP727 on the plasma membrane, and syp123 and vamp727 mutants exhibited lower cell wall stiffness in the root hair shank because of impaired deposition of inner cell wall components. These results indicate that SYP123/VAMP727-mediated secretion is involved in the transport of inner cell wall components for hardening of the root hair shank.

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In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083035 ◽

1978 ◽

Vol 36 (2) ◽

pp. 434-435

Author(s):

D. Reis ◽

B. Vian ◽

J. C. Roland

Keyword(s):

Cell Wall ◽

Self Assembly ◽

Plant Cell Wall ◽

Higher Plants ◽

Three Dimensional ◽

Cytochemical Study ◽

Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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Mitogenic Activity of Cell Wall Components from Lactobacillus acidophilus

Nihon Chikusan Gakkaiho ◽

10.2508/chikusan.64.505 ◽

1993 ◽

Vol 64 (5) ◽

pp. 505-511 ◽

Cited By ~ 1

Author(s):

Masahiro YAMADA ◽

Haruki KITAZAWA ◽

Junko UEMURA ◽

Tadao SAITOH ◽

Takatoshi ITOH

Keyword(s):

Cell Wall ◽

Lactobacillus Acidophilus ◽

Mitogenic Activity ◽

Cell Wall Components ◽

Wall Components

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Ibudilast Mitigates Delayed Bone Healing Caused by Lipopolysaccharide by Altering Osteoblast and Osteoclast Activity

International Journal of Molecular Sciences ◽

10.3390/ijms22031169 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1169

Author(s):

Yuhan Chang ◽

Chih-Chien Hu ◽

Ying-Yu Wu ◽

Steve W. N. Ueng ◽

Chih-Hsiang Chang ◽

...

Keyword(s):

Cell Wall ◽

Bone Formation ◽

Cancellous Bone ◽

Bone Healing ◽

Bone Bridge ◽

Cell Wall Components ◽

Osteoclast Activity ◽

Wall Components

Bacterial infection in orthopedic surgery is challenging because cell wall components released after bactericidal treatment can alter osteoblast and osteoclast activity and impair fracture stability. However, the precise effects and mechanisms whereby cell wall components impair bone healing are unclear. In this study, we characterized the effects of lipopolysaccharide (LPS) on bone healing and osteoclast and osteoblast activity in vitro and in vivo and evaluated the effects of ibudilast, an antagonist of toll-like receptor 4 (TLR4), on LPS-induced changes. In particular, micro-computed tomography was used to reconstruct femoral morphology and analyze callus bone content in a femoral defect mouse model. In the sham-treated group, significant bone bridge and cancellous bone formation were observed after surgery, however, LPS treatment delayed bone bridge and cancellous bone formation. LPS inhibited osteogenic factor-induced MC3T3-E1 cell differentiation, alkaline phosphatase (ALP) levels, calcium deposition, and osteopontin secretion and increased the activity of osteoclast-associated molecules, including cathepsin K and tartrate-resistant acid phosphatase in vitro. Finally, ibudilast blocked the LPS-induced inhibition of osteoblast activation and activation of osteoclast in vitro and attenuated LPS-induced delayed callus bone formation in vivo. Our results provide a basis for the development of a novel strategy for the treatment of bone infection.

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