Mass Spectrometric Imaging of Wheat (Triticum spp.) and Barley (Hordeum vulgare L.) Cultivars: Distribution of Major Cell Wall Polysaccharides According to Their Main Structural Features

Senescence is an ordered degenerative process leading to death of individual cells, organs and organisms. The detection of a conditional lethal mutant (achloroplastic) of Hordeum vulgare has enabled us to investigate ultrastructural changes occurring in leaf tissue during foliar senescence.Examination of the tonoplast structure in six and 14 day-old mutant tissue revealed a progressive degeneration and disappearance of the membrane, apparently starting by day six in the vicinity of the mitochondria associated with the degenerating proplastid (Fig. 1.) where neither of the plastid membrane leaflets is evident (arrows, Fig. 1.). At this stage there was evidence that the mitochondrial membranes were undergoing retrogressive changes, coupled with disorganization of cristae (Fig. 2.). Proplastids (P) lack definitive prolamellar bodies. The cytoplasmic matrix is largely agranular, with few endoplasmic reticulum (ER) cisternae or polyribosomal aggregates. Interestingly, large numbers of actively-budding dictysomes, associated with pinocytotic vesicles, were observed in close proximity to the plasmalemma of mesophyll cells (Fig. 3.). By day 14 however, mesophyll cells showed almost complete breakdown of subcellular organelle structure (Fig. 4.), and further evidence for the breakdown of the tonoplast. The final stage of senescence is characterized by the solubilization of the cell wall due to expression and activity of polygalacturonase and/or cellulose. The presence of dictyosomes with associated pinocytotic vesicles formed from the mature face, in close proximity to both the plasmalemma and the cell wall, would appear to support the model proposed by Christopherson for the secretion of cellulase. This pathway of synthesis is typical for secretory glycoproteins.

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A Possible Role of the Aleurone Expressed Gene HvMAN1 in the Hydrolysis of the Cell Wall Mannans of the Starchy Endosperm in Germinating Hordeum vulgare L. Seeds

Frontiers in Plant Science ◽

10.3389/fpls.2019.01706 ◽

2020 ◽

Vol 10 ◽

Author(s):

Raquel Iglesias-Fernández ◽

Elena Pastor-Mora ◽

Jesús Vicente-Carbajosa ◽

Pilar Carbonero

Keyword(s):

Cell Wall ◽

Hordeum Vulgare ◽

Starchy Endosperm ◽

Hordeum Vulgare L ◽

Hydrolysis Of

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Cell-wall polysaccharides and glycoproteins of parenchymatous tissues of runner bean (Phaseolus coccineus)

Biochemical Journal ◽

10.1042/bj2690393 ◽

1990 ◽

Vol 269 (2) ◽

pp. 393-402 ◽

Cited By ~ 34

Author(s):

P Ryden ◽

R R Selvendran

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Anion Exchange Chromatography ◽

Structural Features ◽

Good Evidence ◽

Exchange Chromatography ◽

Cell Wall Polysaccharides ◽

Pectic Polysaccharides ◽

Runner Bean ◽

Cellulose Residue

1. Polymers were solubilized from the cell walls of parenchyma from mature runner-bean pods with minimum degradation by successive extractions with cyclohexane-trans-1,2-diamine-NNN′N′-tetra-acetate (CDTA), Na2CO3 and KOH to leave the alpha-cellulose residue, which contained cross-linked pectic polysaccharides and Hyp-rich glycoproteins. These were solubilized with chlorite/acetic acid and cellulase. The polymers were fractionated by anion-exchange chromatography, and fractions were subjected to methylation analysis. 2. The pectic polysaccharides differed in their ease of extraction, and a small proportion were highly cross-linked. The bulk of the pectic polysaccharides solubilized by CDTA and Na2CO3 were less branched than those solubilized by KOH. There was good evidence that most of the pectic polysaccharides were not degraded during extraction. 3. The protein-containing fractions included Hyp-rich and Hyp-poor glycoproteins associated with easily extractable pectic polysaccharides, Hyp-rich glycoproteins solubilized with 4M-KOH+borate, the bulk of which were not associated with pectic polysaccharides, and highly cross-linked Hyp-rich glycoproteins. 4. Isodityrosine was not detected, suggesting that it does not have a (major) cross-linking role in these walls. Instead, it is suggested that phenolics, presumably linked to C-5 of 3,5-linked Araf residues of Hyp-rich glycoproteins, serve to cross-link some of the polymers. 5. There were two main types of xyloglucan, with different degrees of branching. The bulk of the less branched xyloglucans were solubilized by more-concentrated alkali. The anomeric configurations of the sugars in one of the highly branched xyloglucans were determined by 13C-n.m.r. spectroscopy. 6. The structural features of the cell-wall polymers and complexes are discussed in relation to the structure of the cell walls of parenchyma tissues.

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Acid phosphatase isoforms in dry seeds and during seedling development in barley (Hordeum vulgare)

Canadian Journal of Botany ◽

10.1139/b96-083 ◽

1996 ◽

Vol 74 (5) ◽

pp. 653-658

Author(s):

S. Pasqualini ◽

P. Batini ◽

L. Ederli ◽

F. Panara ◽

M. Antonielli

Keyword(s):

Cell Wall ◽

Acid Phosphatase ◽

Hordeum Vulgare ◽

Developmental Stages ◽

Soluble Fraction ◽

Polyacrylamide Gel Electrophoresis ◽

Seedling Development ◽

Rapid Decrease ◽

Hordeum Vulgare L ◽

Electrophoretic Patterns

The acid phosphatase activity in the soluble, membrane, and cell wall fractions from Hordeum vulgare in dry seeds and during seedling development was investigated. The acid phosphatase activities were also assayed in barley roots and coleoptiles at different developmental stages. Electrophoretic patterns of multiple acid phosphatases in seeds, endosperms and embryos, and growing roots and coleoptiles are shown. The enzyme activity shows a rapid decrease in both roots and coleoptiles during growth. Using nondenaturing polyacrylamide gel electrophoresis, multiple acid phosphatase forms were found in all the organs examined. However, no qualitative differences in the location of bands were observed between root and coleoptile extract at various stages of development. The coleoptile cell wall fraction showed an acid phosphatase form characterized by a very low electrophoretic mobility that was not found in the soluble fraction. Keywords: barley, Hordeum vulgare L., acid phosphatase, isoforms, seedlings growth.

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Composition and structural features of cell wall polysaccharides from tomato fruits

Phytochemistry ◽

10.1016/0031-9422(90)80008-5 ◽

1990 ◽

Vol 29 (3) ◽

pp. 725-731 ◽

Cited By ~ 99

Author(s):

Graham B. Seymour ◽

Ian J. Colquhoun ◽

M.Susan Dupont ◽

Keith R. Parsley ◽

Robert R. Selvendran

Keyword(s):

Cell Wall ◽

Structural Features ◽

Cell Wall Polysaccharides ◽

Tomato Fruits

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Coffee carbohydrates

Brazilian Journal of Plant Physiology ◽

10.1590/s1677-04202006000100012 ◽

2006 ◽

Vol 18 (1) ◽

pp. 165-174 ◽

Cited By ~ 39

Author(s):

Robert Redgwell ◽

Monica Fischer

Keyword(s):

Cell Wall ◽

Potential Role ◽

Structural Features ◽

Coffee Bean ◽

Cell Wall Polysaccharides ◽

Pectic Polysaccharides ◽

Specific Polysaccharide ◽

Chemical Studies ◽

First Time ◽

Detailed Chemical

This review summarises recent advances in the chemistry, physiology and molecular properties of coffee carbohydrates with a particular focus on the cell wall polysaccharides. The results of detailed chemical studies have demonstrated novel structural features of both the galactomannans and the arabinogalactan polysaccharides of the green and roasted coffee bean. For the first time immunological probes based on monoclonal antibodies for specific polysaccharide epitopes were used to reveal the patterns of distribution of the galactomannans, arabinogalactans and pectic polysaccharides in the coffee bean cell wall. Finally, the results of physiological and molecular studies are presented which emphasise the growing awareness of the potential role the metabolic status of the green bean may play in final coffee beverage quality.

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