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Geng L, Li M, Xie S, Wang H, He X, Sun N, Zhang G, Ye L. HvBGlu3, a GH1 β-glucosidase enzyme gene, negatively influences β-glucan content in barley grains. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2024; 137:14. [PMID: 38165440 DOI: 10.1007/s00122-023-04517-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 12/05/2023] [Indexed: 01/03/2024]
Abstract
KEY MESSAGE HvBGlu3, a β-glucosidase enzyme gene, negatively influences β-glucan content in barley grains by mediating starch and sucrose metabolism in developing grains. Barley grains are rich in β-glucan, an important factor affecting end-use quality. Previously, we identified several stable marker-trait associations (MTAs) and novel candidate genes associated with β-glucan content in barley grains using GWAS (Genome Wide Association Study) analysis. The gene HORVU3Hr1G096910, encoding β-glucosidase 3, named HvBGlu3, is found to be associated with β-glucan content in barley grains. In this study, conserved domain analysis suggested that HvBGlu3 belongs to glycoside hydrolase family 1 (GH1). Gene knockout assay revealed that HvBGlu3 negatively influenced β-glucan content in barley grains. Transcriptome analysis of developing grains of hvbglu3 mutant and the wild type indicated that the knockout of the gene led to the increased expression level of genes involved in starch and sucrose metabolism. Glucose metabolism analysis showed that the contents of many sugars in developing grains were significantly changed in hvbglu3 mutants. In conclusion, HvBGlu3 modulates β-glucan content in barley grains by mediating starch and sucrose metabolism in developing grains. The obtained results may be useful for breeders to breed elite barley cultivars for food use by screening barley lines with loss of function of HvBGlu3 in barley breeding.
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Affiliation(s)
- La Geng
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058, China
| | - Mengdi Li
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058, China
| | - Shanggeng Xie
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058, China
| | - Han Wang
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058, China
| | - Xinyi He
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058, China
| | - Nannan Sun
- Shandong (Linyi) Institute of Modern Agriculture, Zhejiang University, Linyi, 276000, China
| | - Guoping Zhang
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058, China
- Shandong (Linyi) Institute of Modern Agriculture, Zhejiang University, Linyi, 276000, China
| | - Lingzhen Ye
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058, China.
- Shandong (Linyi) Institute of Modern Agriculture, Zhejiang University, Linyi, 276000, China.
- New Rural Development Institute, Zhejiang University, Hangzhou, 310058, China.
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Havrlentová M, Dvořáček V, Jurkaninová L, Gregusová V. Unraveling the Potential of β-D-Glucans in Poales: From Characterization to Biosynthesis and Factors Affecting the Content. Life (Basel) 2023; 13:1387. [PMID: 37374169 DOI: 10.3390/life13061387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/11/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
This review consolidates current knowledge on β-D-glucans in Poales and presents current findings and connections that expand our understanding of the characteristics, functions, and applications of this cell wall polysaccharide. By associating information from multiple disciplines, the review offers valuable insights for researchers, practitioners, and consumers interested in harnessing the benefits of β-D-glucans in various fields. The review can serve as a valuable resource for plant biology researchers, cereal breeders, and plant-based food producers, providing insights into the potential of β-D-glucans and opening new avenues for future research and innovation in the field of this bioactive and functional ingredient.
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Affiliation(s)
- Michaela Havrlentová
- Department of Biotechnology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, Námestie J. Herdu 2, 917 01 Trnava, Slovakia
- National Agricultural and Food Center-Research Institute of Plant Production, Bratislavská cesta 122, 921 68 Piešťany, Slovakia
| | - Václav Dvořáček
- Crop Research Institute, Drnovská 507, 161 06 Prague, Czech Republic
| | - Lucie Jurkaninová
- Department of Food Science, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamýcká 129, 165 00 Praha, Czech Republic
| | - Veronika Gregusová
- Department of Biotechnology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, Námestie J. Herdu 2, 917 01 Trnava, Slovakia
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Perrot T, Pauly M, Ramírez V. Emerging Roles of β-Glucanases in Plant Development and Adaptative Responses. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11091119. [PMID: 35567119 PMCID: PMC9099982 DOI: 10.3390/plants11091119] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/16/2022] [Accepted: 04/18/2022] [Indexed: 05/04/2023]
Abstract
Plant β-glucanases are enzymes involved in the synthesis, remodelling and turnover of cell wall components during multiple physiological processes. Based on the type of the glycoside bond they cleave, plant β-glucanases have been grouped into three categories: (i) β-1,4-glucanases degrade cellulose and other polysaccharides containing 1,4-glycosidic bonds to remodel and disassemble the wall during cell growth. (ii) β-1,3-glucanases are responsible for the mobilization of callose, governing the symplastic trafficking through plasmodesmata. (iii) β-1,3-1,4-glucanases degrade mixed linkage glucan, a transient wall polysaccharide found in cereals, which is broken down to obtain energy during rapid seedling growth. In addition to their roles in the turnover of self-glucan structures, plant β-glucanases are crucial in regulating the outcome in symbiotic and hostile plant-microbe interactions by degrading non-self glucan structures. Plants use these enzymes to hydrolyse β-glucans found in the walls of microbes, not only by contributing to a local antimicrobial defence barrier, but also by generating signalling glucans triggering the activation of global responses. As a counterpart, microbes developed strategies to hijack plant β-glucanases to their advantage to successfully colonize plant tissues. This review outlines our current understanding on plant β-glucanases, with a particular focus on the latest advances on their roles in adaptative responses.
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Jain N, Tamura K, Déjean G, Van Petegem F, Brumer H. Orthogonal Active-Site Labels for Mixed-Linkage endo-β-Glucanases. ACS Chem Biol 2021; 16:1968-1984. [PMID: 33988963 DOI: 10.1021/acschembio.1c00063] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Small molecule irreversible inhibitors are valuable tools for determining catalytically important active-site residues and revealing key details of the specificity, structure, and function of glycoside hydrolases (GHs). β-glucans that contain backbone β(1,3) linkages are widespread in nature, e.g., mixed-linkage β(1,3)/β(1,4)-glucans in the cell walls of higher plants and β(1,3)glucans in yeasts and algae. Commensurate with this ubiquity, a large diversity of mixed-linkage endoglucanases (MLGases, EC 3.2.1.73) and endo-β(1,3)-glucanases (laminarinases, EC 3.2.1.39 and EC 3.2.1.6) have evolved to specifically hydrolyze these polysaccharides, respectively, in environmental niches including the human gut. To facilitate biochemical and structural analysis of these GHs, with a focus on MLGases, we present here the facile chemo-enzymatic synthesis of a library of active-site-directed enzyme inhibitors based on mixed-linkage oligosaccharide scaffolds and N-bromoacetylglycosylamine or 2-fluoro-2-deoxyglycoside warheads. The effectiveness and irreversibility of these inhibitors were tested with exemplar MLGases and an endo-β(1,3)-glucanase. Notably, determination of inhibitor-bound crystal structures of a human-gut microbial MLGase from Glycoside Hydrolase Family 16 revealed the orthogonal labeling of the nucleophile and catalytic acid/base residues with homologous 2-fluoro-2-deoxyglycoside and N-bromoacetylglycosylamine inhibitors, respectively. We anticipate that the selectivity of these inhibitors will continue to enable the structural and mechanistic analyses of β-glucanases from diverse sources and protein families.
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Affiliation(s)
- Namrata Jain
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Kazune Tamura
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Guillaume Déjean
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Harry Brumer
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
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Panahabadi R, Ahmadikhah A, McKee LS, Ingvarsson PK, Farrokhi N. Genome-Wide Association Mapping of Mixed Linkage (1,3;1,4)-β-Glucan and Starch Contents in Rice Whole Grain. FRONTIERS IN PLANT SCIENCE 2021; 12:665745. [PMID: 34512678 PMCID: PMC8424012 DOI: 10.3389/fpls.2021.665745] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 07/28/2021] [Indexed: 05/27/2023]
Abstract
The glucan content of rice is a key factor defining its nutritional and economic value. Starch and its derivatives have many industrial applications such as in fuel and material production. Non-starch glucans such as (1,3;1,4)-β-D-glucan (mixed-linkage β-glucan, MLG) have many benefits in human health, including lowering cholesterol, boosting the immune system, and modulating the gut microbiome. In this study, the genetic variability of MLG and starch contents were analyzed in rice (Oryza sativa L.) whole grain, by performing a new quantitative analysis of the polysaccharide content of rice grains. The 197 rice accessions investigated had an average MLG content of 252 μg/mg, which was negatively correlated with the grain starch content. A new genome-wide association study revealed seven significant quantitative trait loci (QTLs) associated with the MLG content and two QTLs associated with the starch content in rice whole grain. Novel genes associated with the MLG content were a hexose transporter and anthocyanidin 5,3-O-glucosyltransferase. Also, the novel gene associated with the starch content was a nodulin-like domain. The data pave the way for a better understanding of the genes involved in determining both MLG and starch contents in rice grains and should facilitate future plant breeding programs.
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Affiliation(s)
- Rahele Panahabadi
- Department of Plant Science and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, Stockholm, Sweden
| | - Asadollah Ahmadikhah
- Department of Plant Science and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran
| | - Lauren S. McKee
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, Stockholm, Sweden
- Wallenberg Wood Science Centre, Stockholm, Sweden
| | - Pär K. Ingvarsson
- Linnean Centre for Plant Biology, Department of Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Naser Farrokhi
- Department of Plant Science and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran
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Pervaiz T, Liu T, Fang X, Ren Y, Li X, Liu Z, Fiaz M, Fang J, Shangguan L. Identification of GH17 gene family in Vitis vinifera and expression analysis of GH17 under various adversities. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2021; 27:1423-1436. [PMID: 34366587 PMCID: PMC8295436 DOI: 10.1007/s12298-021-01014-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 05/20/2021] [Accepted: 05/27/2021] [Indexed: 06/13/2023]
Abstract
Glycoside hydrolase (GH, EC 3.2.1) is a group of enzymes that hydrolyzes glycosidic bonds and play a role in the hydrolysis and synthesis of sugars in living organisms. Vitis vinifera is an important fruit crop and it harbors GH17 gene family however, their function in grapes has not been systematically investigated. In this study, a total of 870 GH17 genes were identified from 14 plant species and their structural domain, sequence alignment, phylogenetic tree, collinear analysis, with the expression profiles of VviGH17 gene family was performed. The promoter analysis of VviGH17 gene showed the presence of cis-acting elements, which are responsive to plant growth and development. In addition, elements for plant hormones were found that are triggered in response to abiotic/biological stress. Transcriptomic data led to the identification of several VviGH17 genes, which are associated with bud dormancy and in response to abiotic stress. Transcript analysis was carried out for some of the selected VviGH17 genes RT-qPCR. VviGH17-16 and VviGH17-30 genes were differentially expressed during bud dormancy, fruit development and different abiotic stresses. Moreover, VviGH17-37 and VviGH17-44 were differentially expressed at fruit development, in response to abiotic stress. In addition, subcellular localization predicts that the VviGH17-16, VviGH17-30, and VviGH17-37 genes were located in the cell membrane, while VviGH17-44 gene was located in the vacuole. In conclusion, our study led to the identification of several GH17s and their probable role in development and stress. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s12298-021-01014-1.
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Affiliation(s)
- Tariq Pervaiz
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Beijing Advanced Innovation Center for Tree Breeding By Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083 People’s Republic of China
| | - Tianhua Liu
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering, Center of Jiangsu Province, Nanjing, 210095 People’s Republic of China
| | - Xiang Fang
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
| | - Yanhua Ren
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering, Center of Jiangsu Province, Nanjing, 210095 People’s Republic of China
| | - Xiyang Li
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering, Center of Jiangsu Province, Nanjing, 210095 People’s Republic of China
| | - Zhongjie Liu
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering, Center of Jiangsu Province, Nanjing, 210095 People’s Republic of China
| | - Muhammad Fiaz
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering, Center of Jiangsu Province, Nanjing, 210095 People’s Republic of China
| | - Jinggui Fang
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering, Center of Jiangsu Province, Nanjing, 210095 People’s Republic of China
| | - Lingfei Shangguan
- Department of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095 People’s Republic of China
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering, Center of Jiangsu Province, Nanjing, 210095 People’s Republic of China
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Kraemer FJ, Lunde C, Koch M, Kuhn BM, Ruehl C, Brown PJ, Hoffmann P, Göhre V, Hake S, Pauly M, Ramírez V. A mixed-linkage (1,3;1,4)-β-D-glucan specific hydrolase mediates dark-triggered degradation of this plant cell wall polysaccharide. PLANT PHYSIOLOGY 2021; 185:1559-1573. [PMID: 33793956 PMCID: PMC8133622 DOI: 10.1093/plphys/kiab009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 12/17/2020] [Indexed: 05/21/2023]
Abstract
The presence of mixed-linkage (1,3;1,4)-β-d-glucan (MLG) in plant cell walls is a key feature of grass species such as cereals, the main source of calorie intake for humans and cattle. Accumulation of this polysaccharide involves the coordinated regulation of biosynthetic and metabolic machineries. While several components of the MLG biosynthesis machinery have been identified in diverse plant species, degradation of MLG is poorly understood. In this study, we performed a large-scale forward genetic screen for maize (Zea mays) mutants with altered cell wall polysaccharide structural properties. As a result, we identified a maize mutant with increased MLG content in several tissues, including adult leaves and senesced organs, where only trace amounts of MLG are usually detected. The causative mutation was found in the GRMZM2G137535 gene, encoding a GH17 licheninase as demonstrated by an in vitro activity assay of the heterologously expressed protein. In addition, maize plants overexpressing GRMZM2G137535 exhibit a 90% reduction in MLG content, indicating that the protein is not only required, but its expression is sufficient to degrade MLG. Accordingly, the mutant was named MLG hydrolase 1 (mlgh1). mlgh1 plants show increased saccharification yields upon enzymatic digestion. Stacking mlgh1 with lignin-deficient mutations results in synergistic increases in saccharification. Time profiling experiments indicate that wall MLG content is modulated during day/night cycles, inversely associated with MLGH1 transcript accumulation. This cycling is absent in the mlgh1 mutant, suggesting that the mechanism involved requires MLG degradation, which may in turn regulate MLGH1 gene expression.
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Affiliation(s)
- Florian J Kraemer
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California Berkeley, California 94720, USA
| | - China Lunde
- Plant Gene Expression Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California 94710, USA
| | - Moritz Koch
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California Berkeley, California 94720, USA
| | - Benjamin M Kuhn
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California Berkeley, California 94720, USA
| | - Clemens Ruehl
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California Berkeley, California 94720, USA
| | - Patrick J Brown
- Department of Crop Sciences, University of Illinois, Urbana, Illinois 61801, USA
| | - Philipp Hoffmann
- Institute of Microbiology/Group Pathogenicity, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Vera Göhre
- Institute of Microbiology/Group Pathogenicity, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Sarah Hake
- Plant Gene Expression Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California 94710, USA
| | - Markus Pauly
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California Berkeley, California 94720, USA
- Institute for Plant Cell Biology and Biotechnology—Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Vicente Ramírez
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California Berkeley, California 94720, USA
- Institute for Plant Cell Biology and Biotechnology—Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
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Bioactive Components in Oat and Barley Grain as a Promising Breeding Trend for Functional Food Production. Molecules 2021; 26:molecules26082260. [PMID: 33919686 PMCID: PMC8069901 DOI: 10.3390/molecules26082260] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/06/2021] [Accepted: 04/09/2021] [Indexed: 12/20/2022] Open
Abstract
Cereal crops, such as oats and barley, possess a number of valuable properties that meet the requirements for functional diet components. This review summarized the available information about bioactive compounds of oat and barley grain. The results of studying the structure and physicochemical properties of the cell wall polysaccharides of barley and oat are presented. The main components of the flavonoids formation pathway are shown and data, concerning anthocyanins biosynthesis in various barley tissues, are discussed. Moreover, we analyzed the available information about structural and regulatory genes of anthocyanin biosynthesis in Hordeum vulgare L. genome, including β-glucan biosynthesis genes in Avena sativa L species. However, there is not enough knowledge about the genes responsible for biosynthesis of β-glucans and corresponding enzymes and plant polyphenols. The review also covers contemporary studies about collections of oat and barley genetic resources held by the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). This review intended to provide information on the processes of biosynthesis of biologically active compounds in cereals that will promote further researches devoted to transcription factors controlling expression of structural genes and their role in other physiological processes in higher plants. Found achievements will allow breeders to create new highly productive varieties with the desirable properties.
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Zhang J, Yan L, Liu M, Guo G, Wu B. Analysis of β-d-glucan biosynthetic genes in oat reveals glucan synthesis regulation by light. ANNALS OF BOTANY 2021; 127:371-380. [PMID: 33090200 PMCID: PMC7872105 DOI: 10.1093/aob/mcaa185] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 10/18/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND AIMS Oat (Avena sativa) has human health benefits when consumed as a whole-grain food, attributed to the high content of (1,3;1,4)-β-d-glucan (mixed-linkage glucan [MLG]), but little is known about the synthase genes and synthesis mechanism of MLG polysaccharides in this species. METHODS The concentration of oat MLGs under different light intensities was measured by a standard enzymatic approach and further verified by immunoelectron microscopy. The effect of light intensity on MLG synthase genes was examined by RT-qPCR and western blot analyses. The pattern of expression directed by the promoter of the oat MLG synthase gene was also investigated by histochemical β-glucuronidase (GUS) analysis. KEY RESULTS The oat orthologues of genes implicated in the synthesis of MLG in other cereals, including cellulose synthase-like (Csl) F, H and J gene families, were defined. Transcript profiling of these genes across oat tissues indicated that AsCslF6 transcripts dominated. Under high light intensities, the expression of AsCslF6, a major isoform of the MLG synthase genes, increased to >30 % of the dark growth control. The amount of MLG in oat rose from 0.07 to 1.06 % with increased light intensity. Histochemical tests showed that the AsCslF6 gene promoter preferentially directs GUS expression under high light intensity conditions. CONCLUSIONS Oat MLG synthesis is regulated by light. High light intensity upregulates the expression of the MLG synthase AsCslF6 gene, leading to an increase in the amount of MLG in oat leaves.
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Affiliation(s)
- Jing Zhang
- Institute of Crop Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Lin Yan
- Institute of Crop Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Minxuan Liu
- Institute of Crop Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Ganggang Guo
- Institute of Crop Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Bing Wu
- Institute of Crop Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
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Bain M, van de Meene A, Costa R, Doblin MS. Characterisation of Cellulose Synthase Like F6 ( CslF6) Mutants Shows Altered Carbon Metabolism in β-D-(1,3;1,4)-Glucan Deficient Grain in Brachypodium distachyon. FRONTIERS IN PLANT SCIENCE 2021; 11:602850. [PMID: 33505412 PMCID: PMC7829222 DOI: 10.3389/fpls.2020.602850] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
Brachypodium distachyon is a small, fast growing grass species in the Pooideae subfamily that has become established as a model for other temperate cereals of agricultural significance, such as barley (Hordeum vulgare) and wheat (Triticum aestivum). The unusually high content in whole grains of β-D-(1,3;1,4)-glucan or mixed linkage glucan (MLG), considered a valuable dietary fibre due to its increased solubility in water compared with cellulose, makes B. distachyon an attractive model for these polysaccharides. The carbohydrate composition of grain in B. distachyon is interesting not only in understanding the synthesis of MLG, but more broadly in the mechanism(s) of carbon partitioning in cereal grains. Several mutants in the major MLG synthase, cellulose synthase like (CSL) F6, were identified in a screen of a TILLING population that show a loss of function in vitro. Surprisingly, loss of cslf6 synthase capacity appears to have a severe impact on survival, growth, and development in B. distachyon in contrast to equivalent mutants in barley and rice. One mutant, A656T, which showed milder growth impacts in heterozygotes shows a 21% (w/w) reduction in average grain MLG and more than doubling of starch compared with wildtype. The endosperm architecture of grains with the A656T mutation is altered, with a reduction in wall thickness and increased deposition of starch in larger granules than typical of wildtype B. distachyon. Together these changes demonstrate an alteration in the carbon storage of cslf6 mutant grains in response to reduced MLG synthase capacity and a possible cross-regulation with starch synthesis which should be a focus in future work in composition of these grains. The consequences of these findings for the use of B. distachyon as a model species for understanding MLG synthesis, and more broadly the implications for improving the nutritional value of cereal grains through alteration of soluble dietary fibre content are discussed.
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Affiliation(s)
- Melissa Bain
- Australian Research Council (ARC) Centre of Excellence in Plant Cell Walls, The School of BioSciences, The University of Melbourne, Parkville, VIC, Australia
| | - Allison van de Meene
- Australian Research Council (ARC) Centre of Excellence in Plant Cell Walls, The School of BioSciences, The University of Melbourne, Parkville, VIC, Australia
| | - Rafael Costa
- Institute of Plant Sciences Paris-Saclay (IPS2), Centre National de la Recherche Scientifique (CNRS), L’Institut National de Recherche pour L’Agriculture, L’Alimentation et L’Environnement (INRAE), Univ Evry, Université Paris-Saclay, Orsay, France
- Centre National de la Recherche Scientifique (CNRS), L’Institut National de Recherche pour L’Agriculture, L’Alimentation et L’Environnement (INRAE), Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, Orsay, France
| | - Monika S. Doblin
- Australian Research Council (ARC) Centre of Excellence in Plant Cell Walls, The School of BioSciences, The University of Melbourne, Parkville, VIC, Australia
- Department of Animal Plant and Soil Sciences, La Trobe Institute for Agriculture and Food (LIAF), La Trobe University, Melbourne, VIC, Australia
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11
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Geng L, Li M, Xie S, Wu D, Ye L, Zhang G. Identification of genetic loci and candidate genes related to β-glucan content in barley grain by genome-wide association study in International Barley Core Selected Collection. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2021; 41:6. [PMID: 37309529 PMCID: PMC10236047 DOI: 10.1007/s11032-020-01199-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 12/28/2020] [Indexed: 06/13/2023]
Abstract
β-glucan is an important trait to be improved in barley breeding programs, as it greatly affects the quality of the end products when barley grains are used as raw material of feed or malt production or consumed as food for human. Although the genes associated with β-glucan synthesis have been identified, genetic regulation of β-glucan accumulation in barley grains is still completely unclear. In this study, 100 accessions from International Barley Core Selected Collection (BCS) were planted in two environments for two consecutive years to determine the genotypic variation of grain β-glucan content. A genome-wide association study (GWAS) identified 14 stable marker-trait associations (MTAs) (-Log10(P)> 4) for grain β-glucan content. Significantly positive correlation was found between grain β-glucan content and the number of favorable alleles of 14 stable MTAs. Seven putative candidate genes encoding some enzymes in glucose metabolism were found to be associated with β-glucan content. One of the putative genes, HORVU6Hr1G088380, could be an important gene controlling barely β-glucan content, with the SNPs being closely linked in all tested accessions and divided into two haplotypes. High resolution melting (HRM) analysis of the first SNP suggested that the HRM-SNP marker is valid for marker-assisted selection in barley breeding. This study provides useful information for the genes and markers related to grain β-glucan content in barley. Supplementary Information The online version contains supplementary material available at 10.1007/s11032-020-01199-5.
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Affiliation(s)
- La Geng
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058 China
| | - Mengdi Li
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058 China
| | - Shanggeng Xie
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058 China
| | - Dezhi Wu
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058 China
| | - Lingzhen Ye
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058 China
- Shandong (Linyi) Institute of Modern Agriculture, Zhejiang University, Linyi, 276000 China
| | - Guoping Zhang
- Institute of Crop Science, Zhejiang University, Hangzhou, 310058 China
- Shandong (Linyi) Institute of Modern Agriculture, Zhejiang University, Linyi, 276000 China
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12
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Goudar G, Sharma P, Janghu S, Longvah T. Effect of processing on barley β-glucan content, its molecular weight and extractability. Int J Biol Macromol 2020; 162:1204-1216. [DOI: 10.1016/j.ijbiomac.2020.06.208] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/02/2020] [Accepted: 06/22/2020] [Indexed: 01/23/2023]
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13
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Coomey JH, Sibout R, Hazen SP. Grass secondary cell walls, Brachypodium distachyon as a model for discovery. THE NEW PHYTOLOGIST 2020; 227:1649-1667. [PMID: 32285456 DOI: 10.1111/nph.16603] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 03/05/2020] [Indexed: 05/20/2023]
Abstract
A key aspect of plant growth is the synthesis and deposition of cell walls. In specific tissues and cell types including xylem and fibre, a thick secondary wall comprised of cellulose, hemicellulose and lignin is deposited. Secondary cell walls provide a physical barrier that protects plants from pathogens, promotes tolerance to abiotic stresses and fortifies cells to withstand the forces associated with water transport and the physical weight of plant structures. Grasses have numerous cell wall features that are distinct from eudicots and other plants. Study of the model species Brachypodium distachyon as well as other grasses has revealed numerous features of the grass cell wall. These include the characterisation of xylosyl and arabinosyltransferases, a mixed-linkage glucan synthase and hydroxycinnamate acyltransferases. Perhaps the most fertile area for discovery has been the formation of lignins, including the identification of novel substrates and enzyme activities towards the synthesis of monolignols. Other enzymes function as polymerising agents or transferases that modify lignins and facilitate interactions with polysaccharides. The regulatory aspects of cell wall biosynthesis are largely overlapping with those of eudicots, but salient differences among species have been resolved that begin to identify the determinants that define grass cell walls.
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Affiliation(s)
- Joshua H Coomey
- Biology Department, University of Massachusetts, Amherst, MA, 01003, USA
- Plant Biology Graduate Program, University of Massachusetts, Amherst, MA, 01003, USA
| | - Richard Sibout
- Biopolymères Interactions Assemblages, INRAE, UR BIA, F-44316, Nantes, France
| | - Samuel P Hazen
- Biology Department, University of Massachusetts, Amherst, MA, 01003, USA
- Plant Biology Graduate Program, University of Massachusetts, Amherst, MA, 01003, USA
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14
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Marcotuli I, Colasuonno P, Hsieh YSY, Fincher GB, Gadaleta A. Non-Starch Polysaccharides in Durum Wheat: A Review. Int J Mol Sci 2020; 21:ijms21082933. [PMID: 32331292 PMCID: PMC7215680 DOI: 10.3390/ijms21082933] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 02/06/2023] Open
Abstract
Durum wheat is one of most important cereal crops that serves as a staple dietary component for humans and domestic animals. It provides antioxidants, proteins, minerals and dietary fibre, which have beneficial properties for humans, especially as related to the health of gut microbiota. Dietary fibre is defined as carbohydrate polymers that are non-digestible in the small intestine. However, this dietary component can be digested by microorganisms in the large intestine and imparts physiological benefits at daily intake levels of 30–35 g. Dietary fibre in cereal grains largely comprises cell wall polymers and includes insoluble (cellulose, part of the hemicellulose component and lignin) and soluble (arabinoxylans and (1,3;1,4)-β-glucans) fibre. More specifically, certain components provide immunomodulatory and cholesterol lowering activity, faecal bulking effects, enhanced absorption of certain minerals, prebiotic effects and, through these effects, reduce the risk of type II diabetes, cardiovascular disease and colorectal cancer. Thus, dietary fibre is attracting increasing interest from cereal processors, producers and consumers. Compared with other components of the durum wheat grain, fibre components have not been studied extensively. Here, we have summarised the current status of knowledge on the genetic control of arabinoxylan and (1,3;1,4)-β-glucan synthesis and accumulation in durum wheat grain. Indeed, the recent results obtained in durum wheat open the way for the improvement of these important cereal quality parameters.
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Affiliation(s)
- Ilaria Marcotuli
- Department of Agricultural and Environmental Science, University of Bari ‘Aldo Moro’, Via G. Amendola 165/A, 70126 Bari, Italy;
- Correspondence: (I.M.); (A.G.)
| | - Pasqualina Colasuonno
- Department of Agricultural and Environmental Science, University of Bari ‘Aldo Moro’, Via G. Amendola 165/A, 70126 Bari, Italy;
| | - Yves S. Y. Hsieh
- Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, Royal Institute of Technology (KTH), SE106 91 Stockholm, Sweden;
| | - Geoffrey B. Fincher
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA 5064, Australia;
| | - Agata Gadaleta
- Department of Agricultural and Environmental Science, University of Bari ‘Aldo Moro’, Via G. Amendola 165/A, 70126 Bari, Italy;
- Correspondence: (I.M.); (A.G.)
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15
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Differences in protein structural regions that impact functional specificity in GT2 family β-glucan synthases. PLoS One 2019; 14:e0224442. [PMID: 31665152 PMCID: PMC6821405 DOI: 10.1371/journal.pone.0224442] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 10/14/2019] [Indexed: 12/16/2022] Open
Abstract
Most cell wall and secreted β-glucans are synthesised by the CAZy Glycosyltransferase 2 family (www.cazy.org), with different members catalysing the formation of (1,4)-β-, (1,3)-β-, or both (1,4)- and (1,3)-β-glucosidic linkages. Given the distinct physicochemical properties of each of the resultant β-glucans (cellulose, curdlan, and mixed linkage glucan, respectively) are crucial to their biological and biotechnological functions, there is a desire to understand the molecular evolution of synthesis and how linkage specificity is determined. With structural studies hamstrung by the instability of these proteins to solubilisation, we have utilised in silico techniques and the crystal structure for a bacterial cellulose synthase to further understand how these enzymes have evolved distinct functions. Sequence and phylogenetic analyses were performed to determine amino acid conservation, both family-wide and within each sub-family. Further structural analysis centred on comparison of a bacterial curdlan synthase homology model with the bacterial cellulose synthase crystal structure, with molecular dynamics simulations performed with their respective β-glucan products bound in the trans-membrane channel. Key residues that differentially interact with the different β-glucan chains and have sub-family-specific conservation were found to reside at the entrance of the trans-membrane channel. The linkage-specific catalytic activity of these enzymes and hence the type of β-glucan chain built is thus likely determined by the different interactions between the proteins and the first few glucose residues in the channel, which in turn dictates the position of the acceptor glucose. The sequence-function relationships for the bacterial β-glucan synthases pave the way for extending this understanding to other kingdoms, such as plants.
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16
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Anacleto R, Badoni S, Parween S, Butardo VM, Misra G, Cuevas RP, Kuhlmann M, Trinidad TP, Mallillin AC, Acuin C, Bird AR, Morell MK, Sreenivasulu N. Integrating a genome-wide association study with a large-scale transcriptome analysis to predict genetic regions influencing the glycaemic index and texture in rice. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:1261-1275. [PMID: 30549178 PMCID: PMC6575982 DOI: 10.1111/pbi.13051] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 11/15/2018] [Accepted: 11/25/2018] [Indexed: 05/19/2023]
Abstract
Reliably generating rice varieties with low glycaemic index (GI) is an important nutritional intervention given the high rates of Type II diabetes incidences in Asia where rice is staple diet. We integrated a genome-wide association study (GWAS) with a transcriptome-wide association study (TWAS) to determine the genetic basis of the GI in rice. GWAS utilized 305 re-sequenced diverse indica panel comprising ~2.4 million single nucleotide polymorphisms (SNPs) enriched in genic regions. A novel association signal was detected at a synonymous SNP in exon 2 of LOC_Os05g03600 for intermediate-to-high GI phenotypic variation. Another major hotspot region was predicted for contributing intermediate-to-high GI variation, involves 26 genes on chromosome 6 (GI6.1). These set of genes included GBSSI, two hydrolase genes, genes involved in signalling and chromatin modification. The TWAS and methylome sequencing data revealed cis-acting functionally relevant genetic variants with differential methylation patterns in the hot spot GI6.1 region, narrowing the target to 13 genes. Conversely, the promoter region of GBSSI and its alternative splicing allele (G allele of Wxa ) explained the intermediate-to-high GI variation. A SNP (C˃T) at exon-10 was also highlighted in the preceding analyses to influence final viscosity (FV), which is independent of amylose content/GI. The low GI line with GC haplotype confirmed soft texture, while other two low GI lines with GT haplotype were characterized as hard and cohesive. The low GI lines were further confirmed through clinical in vivo studies. Gene regulatory network analysis highlighted the role of the non-starch polysaccharide pathway in lowering GI.
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Affiliation(s)
| | - Saurabh Badoni
- International Rice Research InstituteLos BañosPhilippines
| | - Sabiha Parween
- International Rice Research InstituteLos BañosPhilippines
| | - Vito M. Butardo
- International Rice Research InstituteLos BañosPhilippines
- Department of Chemistry and BiotechnologyFaculty of Science, Engineering and TechnologySwinburne University of TechnologyHawthornVic.Australia
| | - Gopal Misra
- International Rice Research InstituteLos BañosPhilippines
| | | | - Markus Kuhlmann
- The Leibniz Institute of Plant Genetics and Crop Plant Research (IPK)GaterslebenGermany
| | | | | | - Cecilia Acuin
- International Rice Research InstituteLos BañosPhilippines
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17
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Abstract
The investigation of the glycan repertoire of several organisms has revealed a wide variation in terms of structures and abundance of glycan moieties. Among the parasites, it is possible to observe different sets of glycoconjugates across taxa and developmental stages within a species. The presence of distinct glycoconjugates throughout the life cycle of a parasite could relate to the ability of that organism to adapt and survive in different hosts and environments. Carbohydrates on the surface, and in excretory-secretory products of parasites, play essential roles in host-parasite interactions. Carbohydrate portions of complex molecules of parasites stimulate and modulate host immune responses, mainly through interactions with specific receptors on the surface of dendritic cells, leading to the generation of a pattern of response that may benefit parasite survival. Available data reviewed here also show the frequent aspect of parasite immunomodulation of mammalian responses through specific glycan interactions, which ultimately makes these molecules promising in the fields of diagnostics and vaccinology.
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18
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Yue PP, Fu GQ, Hu YJ, Bian J, Li MF, Shi ZJ, Peng F. Changes of Chemical Composition and Hemicelluloses Structure in Differently Aged Bamboo ( Neosinocalamus affinis) Culms. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:9199-9208. [PMID: 30102859 DOI: 10.1021/acs.jafc.8b03516] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
To study the differences in chemical composition analysis and spatial distribution of young Neosinocalamus affinis bamboo, we used the methods of standard of National Renewable Energy Laboratory and confocal Raman microscopy, respectively. It was found that the acid-soluble lignin and acid-insoluble lignin content showed an inverse relationship with the increasing bamboo age. Raman analysis revealed that Raman signal intensity of lignin in both the secondary cell wall and the compound middle lamella regions showed a similar increase trend with growth of bamboo. In addition, eight hemicellulosic fractions were obtained by successively treating holocellulose of the 2-, 4-, 8-, and 12-month-old Neosinocalamus affinis bamboo culms with DMSO and alkaline solution. The ratio of arabinose to xylose of hemicelluloses was increased with the growth of bamboo. FT-IR and NMR analyses revealed that DMSO-soluble hemicelluloses of young bamboo culms are mainly composed of highly substituted xylans and β-d-glucans.
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Affiliation(s)
- Pan-Pan Yue
- Beijing Key Laboratory of Lignocellulosic Chemistry , Beijing Forestry University , No. 35 Tsinghua East Road, Haidian District , Beijing 100083 , China
| | - Gen-Que Fu
- Beijing Key Laboratory of Lignocellulosic Chemistry , Beijing Forestry University , No. 35 Tsinghua East Road, Haidian District , Beijing 100083 , China
| | - Ya-Jie Hu
- Beijing Key Laboratory of Lignocellulosic Chemistry , Beijing Forestry University , No. 35 Tsinghua East Road, Haidian District , Beijing 100083 , China
| | - Jing Bian
- Beijing Key Laboratory of Lignocellulosic Chemistry , Beijing Forestry University , No. 35 Tsinghua East Road, Haidian District , Beijing 100083 , China
| | - Ming-Fei Li
- Beijing Key Laboratory of Lignocellulosic Chemistry , Beijing Forestry University , No. 35 Tsinghua East Road, Haidian District , Beijing 100083 , China
| | - Zheng-Jun Shi
- College of Material Science and Technology , Southwest Forestry University , Kunming 650224 , China
| | - Feng Peng
- Beijing Key Laboratory of Lignocellulosic Chemistry , Beijing Forestry University , No. 35 Tsinghua East Road, Haidian District , Beijing 100083 , China
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19
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Nelson CE, Attia MA, Rogowski A, Morland C, Brumer H, Gardner JG. Comprehensive functional characterization of the glycoside hydrolase family 3 enzymes from Cellvibrio japonicus reveals unique metabolic roles in biomass saccharification. Environ Microbiol 2017; 19:5025-5039. [PMID: 29052930 DOI: 10.1111/1462-2920.13959] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 09/27/2017] [Accepted: 10/08/2017] [Indexed: 12/16/2022]
Abstract
Lignocellulose degradation is central to the carbon cycle and renewable biotechnologies. The xyloglucan (XyG), β(1→3)/β(1→4) mixed-linkage glucan (MLG) and β(1→3) glucan components of lignocellulose represent significant carbohydrate energy sources for saprophytic microorganisms. The bacterium Cellvibrio japonicus has a robust capacity for plant polysaccharide degradation, due to a genome encoding a large contingent of Carbohydrate-Active enZymes (CAZymes), many of whose specific functions remain unknown. Using a comprehensive genetic and biochemical approach, we have delineated the physiological roles of the four C. japonicus glycoside hydrolase family 3 (GH3) members on diverse β-glucans. Despite high protein sequence similarity and partially overlapping activity profiles on disaccharides, these β-glucosidases are not functionally equivalent. Bgl3A has a major role in MLG and sophorose utilization, and supports β(1→3) glucan utilization, while Bgl3B underpins cellulose utilization and supports MLG utilization. Bgl3C drives β(1→3) glucan utilization. Finally, Bgl3D is the crucial β-glucosidase for XyG utilization. This study not only sheds the light on the metabolic machinery of C. japonicus, but also expands the repertoire of characterized CAZymes for future deployment in biotechnological applications. In particular, the precise functional analysis provided here serves as a reference for informed bioinformatics on the genomes of other Cellvibrio and related species.
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Affiliation(s)
- Cassandra E Nelson
- Department of Biological Sciences, University of Maryland, Baltimore County, MD, USA
| | - Mohamed A Attia
- Michael Smith Laboratories, University of British Columbia, Vancouver, Canada.,Department of Chemistry, University of British Columbia, Vancouver, Canada
| | - Artur Rogowski
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Carl Morland
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Harry Brumer
- Michael Smith Laboratories, University of British Columbia, Vancouver, Canada.,Department of Chemistry, University of British Columbia, Vancouver, Canada.,Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada.,Department of Botany, University of British Columbia, Vancouver, Canada
| | - Jeffrey G Gardner
- Department of Biological Sciences, University of Maryland, Baltimore County, MD, USA
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20
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Betts NS, Wilkinson LG, Khor SF, Shirley NJ, Lok F, Skadhauge B, Burton RA, Fincher GB, Collins HM. Morphology, Carbohydrate Distribution, Gene Expression, and Enzymatic Activities Related to Cell Wall Hydrolysis in Four Barley Varieties during Simulated Malting. FRONTIERS IN PLANT SCIENCE 2017; 8:1872. [PMID: 29163597 PMCID: PMC5670874 DOI: 10.3389/fpls.2017.01872] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 10/13/2017] [Indexed: 05/27/2023]
Abstract
Many biological processes, such as cell wall hydrolysis and the mobilisation of nutrient reserves from the starchy endosperm, require stringent regulation to successfully malt barley (Hordeum vulgare) grain in an industrial context. Much of the accumulated knowledge defining these events has been collected from individual, unrelated experiments, and data have often been extrapolated from Petri dish germination, rather than malting, experiments. Here, we present comprehensive morphological, biochemical, and transcript data from a simulated malt batch of the three elite malting cultivars Admiral, Navigator, and Flagship, and the feed cultivar Keel. Activities of lytic enzymes implicated in cell wall and starch depolymerisation in germinated grain have been measured, and transcript data for published cell wall hydrolytic genes have been provided. It was notable that Flagship and Keel exhibited generally similar patterns of enzyme and transcript expression, but exhibited a few key differences that may partially explain Flagship's superior malting qualities. Admiral and Navigator also showed matching expression patterns for these genes and enzymes, but the patterns differed from those of Flagship and Keel, despite Admiral and Navigator having Keel as a common ancestor. Overall (1,3;1,4)-β-glucanase activity differed between cultivars, with lower enzyme levels and concomitantly higher amounts of (1,3;1,4)-β-glucan in the feed variety, Keel, at the end of malting. Transcript levels of the gene encoding (1,3;1,4)-β-glucanase isoenzyme EI were almost three times higher than those encoding isoenzyme EII, suggesting a previously unrecognised importance for isoenzyme EI during malting. Careful morphological examination showed that scutellum epithelial cells in mature dry grain are elongated but expand no further as malting progresses, in contrast to equivalent cells in other cereals, perhaps demonstrating a morphological change in this critical organ over generations of breeding selection. Fluorescent immuno-histochemical labelling revealed the presence of pectin in the nucellus and, for the first time, significant amounts of callose throughout the starchy endosperm of mature grain.
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Affiliation(s)
- Natalie S. Betts
- Australian Research Council Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, University of Adelaide, Waite, Glen Osmond, SA, Australia
| | - Laura G. Wilkinson
- Australian Research Council Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, University of Adelaide, Waite, Glen Osmond, SA, Australia
| | - Shi F. Khor
- Australian Research Council Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, University of Adelaide, Waite, Glen Osmond, SA, Australia
| | - Neil J. Shirley
- Australian Research Council Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, University of Adelaide, Waite, Glen Osmond, SA, Australia
| | - Finn Lok
- Carlsberg Research Laboratory, Copenhagen, Denmark
| | | | - Rachel A. Burton
- Australian Research Council Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, University of Adelaide, Waite, Glen Osmond, SA, Australia
| | - Geoffrey B. Fincher
- Australian Research Council Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, University of Adelaide, Waite, Glen Osmond, SA, Australia
| | - Helen M. Collins
- Australian Research Council Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, University of Adelaide, Waite, Glen Osmond, SA, Australia
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21
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Jirillo E, Carone T, Toffanin R. Exploitation of Old Wheat Properties for Prevention of Human Disease. Nat Prod Commun 2017. [DOI: 10.1177/1934578x1701200605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Cereals occupy an important place in the Mediterranean diet pyramid and carbohydrates derived from whole grains seem to exert a beneficial role. In this context, some ancient wheat varieties such as khorasan wheat ( Triticum turgidum ssp. turanicum) may offer unique nutritional and functional properties to prevent human disease. The current paper reviews specific features of dietary carbohydrates focussing the attention on khorasan wheat and its major potential health benefits once regularly introduced in the diet.
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Affiliation(s)
- Emilio Jirillo
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, University of Bari “Aldo Moro”, 70124 Bari, Italy
| | | | - Renato Toffanin
- Advanced Research Centre for Health, Environment and Space (ARCHES), 70013 Castellana Grotte, Italy
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22
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Dallabernardina P, Schuhmacher F, Seeberger PH, Pfrengle F. Mixed-Linkage Glucan Oligosaccharides Produced by Automated Glycan Assembly Serve as Tools To Determine the Substrate Specificity of Lichenase. Chemistry 2017; 23:3191-3196. [PMID: 28084659 DOI: 10.1002/chem.201605479] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Indexed: 11/11/2022]
Abstract
The mixed-linkage (1→3),(1→4)-d-glucan (MLG) specific glycosyl hydrolase lichenase is an important biochemical tool for the structural characterization of MLGs. It holds potential for application in the brewery, animal feed, and biofuel industries. Several defined MLG oligosaccharides obtained by automated glycan assembly are used to analyze the substrate specificities of Bacillus subtilis lichenase. Two glucose building blocks (BBs), equipped with a temporary fluorenylmethyloxycarbonyl chloride (Fmoc) protecting group in the C-3 or C-4 position, served to assemble different oligosaccharides by using an automated oligosaccharide synthesizer. Light-induced cleavage of the glycan products from the solid support followed by global deprotection provided seven MLG oligosaccharides of different length and connectivity. After incubation of the MLG oligosaccharides with lichenase, the digestion products were analyzed by HPLC-MS. These digestion experiments provided insights into the enzyme's active site that is in line with other recent evidence suggesting that the substrate specificity of lichenases has to be reconsidered. These results demonstrate that synthetic MLG oligosaccharides are useful tools to analyze mixed-linkage β-glucanases.
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Affiliation(s)
- Pietro Dallabernardina
- Current address: Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Freie Universität Berlin, Institute of Chemistry and Biochemistry, Arnimallee 22, 14195, Berlin, Germany
| | - Frank Schuhmacher
- Current address: Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Freie Universität Berlin, Institute of Chemistry and Biochemistry, Arnimallee 22, 14195, Berlin, Germany
| | - Peter H Seeberger
- Current address: Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Freie Universität Berlin, Institute of Chemistry and Biochemistry, Arnimallee 22, 14195, Berlin, Germany
| | - Fabian Pfrengle
- Current address: Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Freie Universität Berlin, Institute of Chemistry and Biochemistry, Arnimallee 22, 14195, Berlin, Germany
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23
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McGregor N, Yin V, Tung CC, Van Petegem F, Brumer H. Crystallographic insight into the evolutionary origins of xyloglucan endotransglycosylases and endohydrolases. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 89:651-670. [PMID: 27859885 PMCID: PMC5315667 DOI: 10.1111/tpj.13421] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 10/14/2016] [Accepted: 11/04/2016] [Indexed: 05/22/2023]
Abstract
The xyloglucan endotransglycosylase/hydrolase (XTH) gene family encodes enzymes of central importance to plant cell wall remodeling. The evolutionary history of plant XTH gene products is incompletely understood vis-à-vis the larger body of bacterial endoglycanases in Glycoside Hydrolase Family 16 (GH16). To provide molecular insight into this issue, high-resolution X-ray crystal structures and detailed enzyme kinetics of an extant transitional plant endoglucanase (EG) were determined. Functionally intermediate between plant XTH gene products and bacterial licheninases of GH16, Vitis vinifera EG16 (VvEG16) effectively catalyzes the hydrolysis of the backbones of two dominant plant cell wall matrix glycans, xyloglucan (XyG) and β(1,3)/β(1,4)-mixed-linkage glucan (MLG). Crystallographic complexes with extended oligosaccharide substrates reveal the structural basis for the accommodation of both unbranched, mixed-linked (MLG) and highly decorated, linear (XyG) polysaccharide chains in a broad, extended active-site cleft. Structural comparison with representative bacterial licheninases, a xyloglucan endotranglycosylase (XET), and a xyloglucan endohydrolase (XEH) outline the functional ramifications of key sequence deletions and insertions across the phylogenetic landscape of GH16. Although the biological role(s) of EG16 orthologs remains to be fully resolved, the present biochemical and tertiary structural characterization provides key insight into plant cell wall enzyme evolution, which will continue to inform genomic analyses and functional studies across species.
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Affiliation(s)
- Nicholas McGregor
- Michael Smith Laboratories, University of British Columbia,
2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Chemistry, University of British Columbia,
2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Victor Yin
- Michael Smith Laboratories, University of British Columbia,
2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Chemistry, University of British Columbia,
2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Ching-Chieh Tung
- Department of Biochemistry and Molecular Biology,
University of British Columbia, 2350 Health Sciences Mall, Vancouver, British
Columbia V6T 1Z3, Canada
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology,
University of British Columbia, 2350 Health Sciences Mall, Vancouver, British
Columbia V6T 1Z3, Canada
| | - Harry Brumer
- Michael Smith Laboratories, University of British Columbia,
2185 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Chemistry, University of British Columbia,
2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
- Department of Biochemistry and Molecular Biology,
University of British Columbia, 2350 Health Sciences Mall, Vancouver, British
Columbia V6T 1Z3, Canada
- Department of Botany, University of British Columbia, 6270
University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada
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24
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Han N, Na C, Chai Y, Chen J, Zhang Z, Bai B, Bian H, Zhang Y, Zhu M. Over-expression of (1,3;1,4)-β-D-glucanase isoenzyme EII gene results in decreased (1,3;1,4)-β-D-glucan content and increased starch level in barley grains. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2017; 97:122-127. [PMID: 26927391 DOI: 10.1002/jsfa.7695] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 08/24/2015] [Accepted: 02/25/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND High content of (1,3;1,4)-β-d-glucan in barley grains is regarded as an undesirable factor affecting malting potential, brewing yield and feed utilization. Production of thermostable bacterial (1,3;1,4)-β-glucanase in transgenic barley grain or supplementation of exogenous bacterial (1,3;1,4)-β-glucanase has been used to improve malt and feed quality. The aim of the present study was to investigate the effect of over-expression of an endogenous (1,3;1,4)-β-glucanase on β-glucan content and grain composition in barley. RESULTS A construct containing full-length HvGlb2 cDNA encoding barley (1,3;1,4)-β-glucanase isoenzyme EII under the control of a promoter of barley D-Hordein gene Hor3-1 was introduced into barley cultivar Golden Promise via Agrobacterium-mediated transformation, and transgenic plants were regenerated after hygromycin selection. The T2 generation of proHor3:HvGlb2 transgenic lines showed increased activity of (1,3;1,4)-β-glucanase in grains. Total β-glucan content was reduced by more than 95.73% in transgenic grains compared with the wild-type control. Meanwhile, over-expression of (1,3;1,4)-β-glucanase led to an increase in 1000-grain weight, which might be due to elevated amounts of starch in the grain. CONCLUSION Manipulating the expression of (1,3;1,4)-β-glucanase EII can control the β-glucan content in grain with no apparent harmful effects on grain quality of transgenic plants. © 2016 Society of Chemical Industry.
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Affiliation(s)
- Ning Han
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Chenglong Na
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Yuqiong Chai
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Jianshu Chen
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Zhongbo Zhang
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Bin Bai
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Hongwu Bian
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Yuhong Zhang
- Tibet Academy of Agricultural and Animal Husbandry Sciences, China
| | - Muyuan Zhu
- Key Laboratory for Cell and Gene Engineering of Zhejiang Province, Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang, China
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25
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Giannoutsou E, Apostolakos P, Galatis B. Spatio-temporal diversification of the cell wall matrix materials in the developing stomatal complexes of Zea mays. PLANTA 2016; 244:1125-1143. [PMID: 27460945 DOI: 10.1007/s00425-016-2574-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 07/20/2016] [Indexed: 05/02/2023]
Abstract
The matrix cell wall materials, in developing Zea mays stomatal complexes are asymmetrically distributed, a phenomenon appearing related to the local cell wall expansion and deformation, the establishment of cell polarity, and determination of the cell division plane. In cells of developing Zea mays stomatal complexes, definite cell wall regions expand determinately and become locally deformed. This differential cell wall behavior is obvious in the guard cell mother cells (GMCs) and the subsidiary cell mother cells (SMCs) that locally protrude towards the adjacent GMCs. The latter, emitting a morphogenetic stimulus, induce polarization/asymmetrical division in SMCs. Examination of immunolabeled specimens revealed that homogalacturonans (HGAs) with a high degree of de-esterification (2F4- and JIM5-HGA epitopes) and arabinogalactan proteins are selectively distributed in the extending and deformed cell wall regions, while their margins are enriched with rhamnogalacturonans (RGAs) containing highly branched arabinans (LM6-RGA epitope). In SMCs, the local cell wall matrix differentiation constitutes the first structural event, indicating the establishment of cell polarity. Moreover, in the premitotic GMCs and SMCs, non-esterified HGAs (2F4-HGA epitope) are preferentially localized in the cell wall areas outlining the cytoplasm where the preprophase band is formed. In these areas, the forthcoming cell plate fuses with the parent cell walls. These data suggest that the described heterogeneity in matrix cell wall materials is probably involved in: (a) local cell wall expansion and deformation, (b) the transduction of the inductive GMC stimulus, and
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Affiliation(s)
- E Giannoutsou
- Section of Botany, Department of Biology, National and Kapodistrian University of Athens, 15784, Athens, Greece
| | - P Apostolakos
- Section of Botany, Department of Biology, National and Kapodistrian University of Athens, 15784, Athens, Greece
| | - B Galatis
- Section of Botany, Department of Biology, National and Kapodistrian University of Athens, 15784, Athens, Greece.
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26
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Marcotuli I, Hsieh YSY, Lahnstein J, Yap K, Burton RA, Blanco A, Fincher GB, Gadaleta A. Structural Variation and Content of Arabinoxylans in Endosperm and Bran of Durum Wheat (Triticum turgidum L.). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:2883-2892. [PMID: 27018210 DOI: 10.1021/acs.jafc.6b00103] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Arabinoxylans are one group of dietary fiber components in cereal grains, and specific health benefits have been linked with their molecular fine structures and hence with physicochemical properties such as solubility in aqueous media. To characterize the fiber quality for functional foods, starchy endosperm and bran fractions from 11 durum wheat lines were analyzed for total and water-soluble arabinoxylans, (1,3;1,4)-β-glucan, and bound ferulic acid. The arabinoxylan contents ranged from 11 to 16.4% (w/w) in bran and from 1.5 to 1.8% in the starchy endosperm. Of the starchy endosperm arabinoxylans, 37% was soluble in water. No correlation was found between arabinoxylan content and bound ferulic acid in bran, although a relatively high level of this antioxidant was found in endosperm (38.3 μg/g endosperm flour). Enzymatic fingerprinting was performed to define the major fine structural features of arabinoxylans from both regions of the grain. Five major oligosaccharides released by xylanase hydrolysis were identified and characterized in the 11 durum lines. In addition, DP5, DP6, and DP7 oligosaccharides containing five, six, and seven pentosyl residues, respectively, were purified.
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Affiliation(s)
- Ilaria Marcotuli
- Department of Soil, Plant and Food Sciences, Section of Genetics and Plant Breeding, University of Bari 'Aldo Moro' , Via G. Amendola 165/A, 70126 Bari, Italy
| | - Yves S-Y Hsieh
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide , Waite Campus, Glen Osmond, SA 5064, Australia
- Division of Glycoscience, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Centre , Stockholm SE-10691, Sweden
| | - Jelle Lahnstein
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide , Waite Campus, Glen Osmond, SA 5064, Australia
| | - Kuok Yap
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide , Waite Campus, Glen Osmond, SA 5064, Australia
| | - Rachel Anita Burton
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide , Waite Campus, Glen Osmond, SA 5064, Australia
| | - Antonio Blanco
- Division of Glycoscience, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Centre , Stockholm SE-10691, Sweden
| | - Geoffrey Bruce Fincher
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide , Waite Campus, Glen Osmond, SA 5064, Australia
| | - Agata Gadaleta
- Department of Agricultural and Environmental Science, University of Bari 'Aldo Moro' , Via G. Amendola 165/A, 70126 Bari, Italy
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27
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Marcotuli I, Houston K, Schwerdt JG, Waugh R, Fincher GB, Burton RA, Blanco A, Gadaleta A. Genetic Diversity and Genome Wide Association Study of β-Glucan Content in Tetraploid Wheat Grains. PLoS One 2016; 11:e0152590. [PMID: 27045166 PMCID: PMC4821454 DOI: 10.1371/journal.pone.0152590] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/16/2016] [Indexed: 12/20/2022] Open
Abstract
Non-starch polysaccharides (NSPs) have many health benefits, including immunomodulatory activity, lowering serum cholesterol, a faecal bulking effect, enhanced absorption of certain minerals, prebiotic effects and the amelioration of type II diabetes. The principal components of the NSP in cereal grains are (1,3;1,4)-β-glucans and arabinoxylans. Although (1,3;1,4)-β-glucan (hereafter called β-glucan) is not the most representative component of wheat cell walls, it is one of the most important types of soluble fibre in terms of its proven beneficial effects on human health. In the present work we explored the genetic variability of β-glucan content in grains from a tetraploid wheat collection that had been genotyped with a 90k-iSelect array, and combined this data to carry out an association analysis. The β-glucan content, expressed as a percentage w/w of grain dry weight, ranged from 0.18% to 0.89% across the collection. Our analysis identified seven genomic regions associated with β-glucan, located on chromosomes 1A, 2A (two), 2B, 5B and 7A (two), confirming the quantitative nature of this trait. Analysis of marker trait associations (MTAs) in syntenic regions of several grass species revealed putative candidate genes that might influence β-glucan levels in the endosperm, possibly via their participation in carbon partitioning. These include the glycosyl hydrolases endo-β-(1,4)-glucanase (cellulase), β-amylase, (1,4)-β-xylan endohydrolase, xylanase inhibitor protein I, isoamylase and the glycosyl transferase starch synthase II.
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Affiliation(s)
- Ilaria Marcotuli
- Department of Soil, Plant and Food Sciences, Section of Genetics and Plant Breeding, University of Bari ‘Aldo Moro’, Via G. Amendola 165/A, 70126, Bari, Italy
| | - Kelly Houston
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, Scotland
| | - Julian G. Schwerdt
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA 5064, Australia
| | - Robbie Waugh
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, Scotland
| | - Geoffrey B. Fincher
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA 5064, Australia
| | - Rachel A. Burton
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA 5064, Australia
| | - Antonio Blanco
- Department of Soil, Plant and Food Sciences, Section of Genetics and Plant Breeding, University of Bari ‘Aldo Moro’, Via G. Amendola 165/A, 70126, Bari, Italy
| | - Agata Gadaleta
- Agricultural and Environmental Science, University of Bari ‘Aldo Moro’, Via G. Amendola 165/A, 70126, Bari, Italy
- * E-mail:
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28
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Ermawar RA, Collins HM, Byrt CS, Henderson M, O'Donovan LA, Shirley NJ, Schwerdt JG, Lahnstein J, Fincher GB, Burton RA. Genetics and physiology of cell wall polysaccharides in the model C4 grass, Setaria viridis spp. BMC PLANT BIOLOGY 2015; 15:236. [PMID: 26432387 PMCID: PMC4592572 DOI: 10.1186/s12870-015-0624-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/21/2015] [Indexed: 05/21/2023]
Abstract
BACKGROUND Setaria viridis has emerged as a model species for the larger C4 grasses. Here the cellulose synthase (CesA) superfamily has been defined, with an emphasis on the amounts and distribution of (1,3;1,4)-β-glucan, a cell wall polysaccharide that is characteristic of the grasses and is of considerable value for human health. METHODS Orthologous relationship of the CesA and Poales-specific cellulose synthase-like (Csl) genes among Setaria italica (Si), Sorghum bicolor (Sb), Oryza sativa (Os), Brachypodium distachyon (Bradi) and Hordeum vulgare (Hv) were compared using bioinformatics analysis. Transcription profiling of Csl gene families, which are involved in (1,3;1,4)-β-glucan synthesis, was performed using real-time quantitative PCR (Q-PCR). The amount of (1,3;1,4)-β-glucan was measured using a modified Megazyme assay. The fine structures of the (1,3;1,4)-β-glucan, as denoted by the ratio of cellotriosyl to cellotetraosyl residues (DP3:DP4 ratio) was assessed by chromatography (HPLC and HPAEC-PAD). The distribution and deposition of the MLG was examined using the specific antibody BG-1 and captured using fluorescence and transmission electron microscopy (TEM). RESULTS The cellulose synthase gene superfamily contains 13 CesA and 35 Csl genes in Setaria. Transcript profiling of CslF, CslH and CslJ gene families across a vegetative tissue series indicated that SvCslF6 transcripts were the most abundant relative to all other Csl transcripts. The amounts of (1,3;1,4)-β-glucan in Setaria vegetative tissues ranged from 0.2% to 2.9% w/w with much smaller amounts in developing grain (0.003% to 0.013% w/w). In general, the amount of (1,3;1,4)-β-glucan was greater in younger than in older tissues. The DP3:DP4 ratios varied between tissue types and across developmental stages, and ranged from 2.4 to 3.0:1. The DP3:DP4 ratios in developing grain ranged from 2.5 to 2.8:1. Micrographs revealing the distribution of (1,3;1,4)-β-glucan in walls of different cell types and the data were consistent with the quantitative (1,3;1,4)-β-glucan assays. CONCLUSION The characteristics of the cellulose synthase gene superfamily and the accumulation and distribution of (1,3;1,4)-β-glucans in Setaria are similar to those in other C4 grasses, including sorghum. This suggests that Setaria is a suitable model plant for cell wall polysaccharide biology in C4 grasses.
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Affiliation(s)
- Riksfardini A Ermawar
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Helen M Collins
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Caitlin S Byrt
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Marilyn Henderson
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Lisa A O'Donovan
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Neil J Shirley
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Julian G Schwerdt
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Jelle Lahnstein
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Geoffrey B Fincher
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
| | - Rachel A Burton
- Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
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29
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Vega-Sánchez ME, Loqué D, Lao J, Catena M, Verhertbruggen Y, Herter T, Yang F, Harholt J, Ebert B, Baidoo EEK, Keasling JD, Scheller HV, Heazlewood JL, Ronald PC. Engineering temporal accumulation of a low recalcitrance polysaccharide leads to increased C6 sugar content in plant cell walls. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:903-14. [PMID: 25586315 DOI: 10.1111/pbi.12326] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 11/11/2014] [Accepted: 12/10/2014] [Indexed: 05/10/2023]
Abstract
Reduced cell wall recalcitrance and increased C6 monosaccharide content are desirable traits for future biofuel crops, as long as these biomass modifications do not significantly alter normal growth and development. Mixed-linkage glucan (MLG), a cell wall polysaccharide only present in grasses and related species among flowering plants, is comprised of glucose monomers linked by both β-1,3 and β-1,4 bonds. Previous data have shown that constitutive production of MLG in barley (Hordeum vulgare) severely compromises growth and development. Here, we used spatio-temporal strategies to engineer Arabidopsis thaliana plants to accumulate significant amounts of MLG in the cell wall by expressing the rice CslF6 MLG synthase using secondary cell wall and senescence-associated promoters. Results using secondary wall promoters were suboptimal. When the rice MLG synthase was expressed under the control of a senescence-associated promoter, we obtained up to four times more glucose in the matrix cell wall fraction and up to a 42% increase in saccharification compared to control lines. Importantly, these plants grew and developed normally. The induction of MLG deposition at senescence correlated with an increase of gluconic acid in cell wall extracts of transgenic plants in contrast to the other approaches presented in this study. MLG produced in Arabidopsis has an altered structure compared to the grass glucan, which likely affects its solubility, while its molecular size is unaffected. The induction of cell wall polysaccharide biosynthesis in senescing tissues offers a novel engineering alternative to enhance cell wall properties of lignocellulosic biofuel crops.
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Affiliation(s)
- Miguel E Vega-Sánchez
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Dominique Loqué
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jeemeng Lao
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Michela Catena
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Yves Verhertbruggen
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Thomas Herter
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Fan Yang
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jesper Harholt
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Berit Ebert
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Edward E K Baidoo
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jay D Keasling
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Chemical and Biomolecular Engineering, and Department of Bioengineering, University of California, Berkeley, CA, USA
| | - Henrik V Scheller
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Joshua L Heazlewood
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Pamela C Ronald
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant Pathology and the Genome Center, University of California, Davis, CA, USA
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30
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Tavares EQP, De Souza AP, Buckeridge MS. How endogenous plant cell-wall degradation mechanisms can help achieve higher efficiency in saccharification of biomass. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:4133-43. [PMID: 25922489 DOI: 10.1093/jxb/erv171] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Cell-wall recalcitrance to hydrolysis still represents one of the major bottlenecks for second-generation bioethanol production. This occurs despite the development of pre-treatments, the prospect of new enzymes, and the production of transgenic plants with less-recalcitrant cell walls. Recalcitrance, which is the intrinsic resistance to breakdown imposed by polymer assembly, is the result of inherent limitations in its three domains. These consist of: (i) porosity, associated with a pectin matrix impairing trafficking through the wall; (ii) the glycomic code, which refers to the fine-structural emergent complexity of cell-wall polymers that are unique to cells, tissues, and species; and (iii) cellulose crystallinity, which refers to the organization in micro- and/or macrofibrils. One way to circumvent recalcitrance could be by following cell-wall hydrolysis strategies underlying plant endogenous mechanisms that are optimized to precisely modify cell walls in planta. Thus, the cell-wall degradation that occurs during fruit ripening, abscission, storage cell-wall mobilization, and aerenchyma formation are reviewed in order to highlight how plants deal with recalcitrance and which are the routes to couple prospective enzymes and cocktail designs with cell-wall features. The manipulation of key enzyme levels in planta can help achieving biologically pre-treated walls (i.e. less recalcitrant) before plants are harvested for bioethanol production. This may be helpful in decreasing the costs associated with producing bioethanol from biomass.
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Affiliation(s)
- Eveline Q P Tavares
- Laboratory of Plant Physiological Ecology (LAFIECO), Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, São Paulo, SP, Brazil
| | - Amanda P De Souza
- Laboratory of Plant Physiological Ecology (LAFIECO), Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, São Paulo, SP, Brazil
| | - Marcos S Buckeridge
- Laboratory of Plant Physiological Ecology (LAFIECO), Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, São Paulo, SP, Brazil
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Ermawar RA, Collins HM, Byrt CS, Betts NS, Henderson M, Shirley NJ, Schwerdt J, Lahnstein J, Fincher GB, Burton RA. Distribution, structure and biosynthetic gene families of (1,3;1,4)-β-glucan in Sorghum bicolor. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2015; 57:429-45. [PMID: 25661466 DOI: 10.1111/jipb.12338] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 02/03/2015] [Indexed: 05/22/2023]
Abstract
In cereals, the presence of soluble polysaccharides including (1,3;1,4)-β-glucan has downstream implications for human health, animal feed and biofuel applications. Sorghum bicolor (L.) Moench is a versatile crop, but there are limited reports regarding the content of such soluble polysaccharides. Here, the amount of (1,3;1,4)-β-glucan present in sorghum tissues was measured using a Megazyme assay. Very low amounts were present in the grain, ranging from 0.16%-0.27% (w/w), while there was a greater quantity in vegetative tissues at 0.12-1.71% (w/w). The fine structure of (1,3;1,4)-β-glucan, as denoted by the ratio of cellotriosyl and cellotetraosyl residues, was assessed by high performance liquid chromatography (HPLC) and ranged from 2.6-3:1 in the grain, while ratios in vegetative tissues were lower at 2.1-2.6:1. The distribution of (1,3;1,4)-β-glucan was examined using a specific antibody and observed with fluorescence and transmission electron microscopy. Micrographs showed a variable distribution of (1,3;1,4)-β-glucan influenced by temporal and spatial factors. The sorghum orthologs of genes implicated in the synthesis of (1,3;1,4)-β-glucan in other cereals, such as the Cellulose synthase-like (Csl) F and H gene families were defined. Transcript profiling of these genes across sorghum tissues was carried out using real-time quantitative polymerase chain reaction, indicating that, as in other cereals, CslF6 transcripts dominated.
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Affiliation(s)
- Riksfardini A Ermawar
- Australian Research Council Centre of Excellence in Plant Cell Walls, University of Adelaide, Glen Osmond, SA, 5064, Australia
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32
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Kim SJ, Zemelis S, Keegstra K, Brandizzi F. The cytoplasmic localization of the catalytic site of CSLF6 supports a channeling model for the biosynthesis of mixed-linkage glucan. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 81:537-47. [PMID: 25557048 DOI: 10.1111/tpj.12748] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/04/2014] [Accepted: 12/11/2014] [Indexed: 05/17/2023]
Abstract
Mixed-linkage glucan (MLG) is a significant cell wall carbohydrate in grasses and an important carbon source for human consumption and biofuel production. MLG biosynthesis depends on the biochemical activity of membrane spanning glucan synthases encoded by the CSLH and CSLF cellulose synthase-like gene families. CSLF proteins are the best characterized to date but relatively little information is known about their topology with respect to the biosynthetic membranes. In this study, we report on the topology of CSLF6 protein derived from the model grass species Brachypodium distachyon (BdCSLF6) when it is expressed in heterologous systems. Using live cell imaging and immuno-electron microscopy analyses of tobacco epidermal cells expressing BdCSLF6, we demonstrate that a functional yellow fluorescent protein (YFP) fusion of BdCSLF6 is localized to the Golgi apparatus and that the Golgi localization of BdCSLF6 is sufficient for MLG biosynthesis. By implementing protease protection assays of BdCSLF6 expressed in the yeast Pichia pastoris, we also demonstrate that the catalytic domain, the N-terminus and the C- terminus of the protein are exposed in the cytosol. Furthermore, we found that BdCSLF6 is capable of producing MLG not only in tobacco cells but also in Pichia, which generally does not produce MLG. Together, these results support the conclusion that BdCSLF6 can produce both of the linkages present in the (1,3;1,4)-β-d-glucan chain of MLG and that the product is channelled at the Golgi into the secretory pathway for deposition into the cell wall.
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Affiliation(s)
- Sang-Jin Kim
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, 48824, USA
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Takahashi M, Yamamoto R, Sakurai N, Nakano Y, Takeda T. Fungal hemicellulose-degrading enzymes cause physical property changes concomitant with solubilization of cell wall polysaccharides. PLANTA 2015; 241:359-370. [PMID: 25301670 DOI: 10.1007/s00425-014-2176-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 09/13/2014] [Indexed: 06/04/2023]
Abstract
Physical properties of wheat coleoptile segments decreased after treatment with hemicellulose-degrading enzymes, indicating that hemicellulosic polysaccharides function to control the strength of primary cell walls. Changes in the physical properties of plant cell walls, a viscoelastic structure, are thought to be one of the growth-limiting factors for plants and one of the infection-affecting factors for fungi. To study the significance of hemicellulosic polysaccharides that form cross-bridges between cellulose microfibrils in controlling cell wall strength in monocot plants, the effects of hemicellulose degradation by recombinant Magnaporthe oryzae xylanase and 1,3-1,4-β-glucanase, and recombinant Aspergillus oryzae xyloglucanase on the physical properties and polysaccharide solubilization were investigated using wheat (Triticum aestivum L.) coleoptiles. Treatments with xylanase or 1,3-1,4-β-glucanase significantly decreased the viscosity and elasticity of wheat coleoptile segments. In addition, xyloglucanase treatment slightly decreased the viscoelasticity. Furthermore, 1,3-1,4-β-glucan polymer was solubilized during hydrolysis with xylanase and xyloglucanase, even though neither enzyme had hydrolytic activity towards 1,3-1,4-β-glucan. These results suggest that xylan and xyloglucan interact with 1,3-1,4-β-glucan and that the composites and hemicellulosic polysaccharides form inter-molecular bridges. Degradation of these bridges causes decreases in the physical properties, resulting in increased extensibility of the cell walls. These findings provide a testable model in which wheat coleoptile cell walls are loosened by the degradation of hemicellulosic polysaccharides and hemicellulose-degrading enzymes play a significant role in loosening the walls during fungal infection.
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Affiliation(s)
- Machiko Takahashi
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate, 024-0003, Japan
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Houston K, Russell J, Schreiber M, Halpin C, Oakey H, Washington JM, Booth A, Shirley N, Burton RA, Fincher GB, Waugh R. A genome wide association scan for (1,3;1,4)-β-glucan content in the grain of contemporary 2-row Spring and Winter barleys. BMC Genomics 2014; 15:907. [PMID: 25326272 PMCID: PMC4213503 DOI: 10.1186/1471-2164-15-907] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 09/24/2014] [Indexed: 11/10/2022] Open
Abstract
Background (1,3;1,4)-β-Glucan is an important component of the cell walls of barley grain as it affects processability during the production of alcoholic beverages and has significant human health benefits when consumed above recommended threshold levels. This leads to diametrically opposed quality requirements for different applications as low levels of (1,3;1,4)-β-glucan are required for brewing and distilling and high levels for positive impacts on human health. Results We quantified grain (1,3;1,4)-β-glucan content in a collection of 399 2-row Spring-type, and 204 2-row Winter-type elite barley cultivars originating mainly from north western Europe. We combined these data with genotypic information derived using a 9 K Illumina iSelect SNP platform and subsequently carried out a Genome Wide Association Scan (GWAS). Statistical analysis accounting for residual genetic structure within the germplasm collection allowed us to identify significant associations between molecular markers and the phenotypic data. By anchoring the regions that contain these associations to the barley genome assembly we catalogued genes underlying the associations. Based on gene annotations and transcript abundance data we identified candidate genes. Conclusions We show that a region of the genome on chromosome 2 containing a cluster of CELLULOSE SYNTHASE-LIKE (Csl) genes, including CslF3, CslF4, CslF8, CslF10, CslF12 and CslH, as well as a region on chromosome 1H containing CslF9, are associated with the phenotype in this germplasm. We also observed that several regions identified by GWAS contain glycoside hydrolases that are possibly involved in (1,3;1,4)-β-glucan breakdown, together with other genes that might participate in (1,3;1,4)-β-glucan synthesis, re-modelling or regulation. This analysis provides new opportunities for understanding the genes related to the regulation of (1,3;1,4)-β-glucan content in cereal grains. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-907) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Robbie Waugh
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland.
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Kozlova LV, Ageeva MV, Ibragimova NN, Gorshkova TA. Arrangement of mixed-linkage glucan and glucuronoarabinoxylan in the cell walls of growing maize roots. ANNALS OF BOTANY 2014; 114:1135-45. [PMID: 25086589 PMCID: PMC4195558 DOI: 10.1093/aob/mcu125] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 05/01/2014] [Indexed: 05/08/2023]
Abstract
BACKGROUND AND AIMS Plant cell enlargement is unambiguously coupled to changes in cell wall architecture, and as such various studies have examined the modification of the proportions and structures of glucuronoarabinoxylan and mixed-linkage glucan in the course of cell elongation in grasses. However, there is still no clear understanding of the mutual arrangement of these matrix polymers with cellulose microfibrils and of the modification of this architecture during cell growth. This study aimed to determine the correspondence between the fine structure of grass cell walls and the course of the elongation process in roots of maize (Zea mays). METHODS Enzymatic hydrolysis followed by biochemical analysis of derivatives was coupled with immunohistochemical detection of cell wall epitopes at different stages of cell development in a series of maize root zones. KEY RESULTS Two xylan-directed antibodies (LM11 and ABX) have distinct patterns of primary cell wall labelling in cross-sections of growing maize roots. The LM11 epitopes were masked by mixed-linkage glucan and were revealed only after lichenase treatment. They could be removed from the section by xylanase treatment. Accessibility of ABX epitopes was not affected by the lichenase treatment. Xylanase treatment released only part of the cell wall glucuronoarabinoxylan and produced two types of products: high-substituted (released in polymeric form) and low-substituted (released as low-molecular-mass fragments). The amount of the latter was highly correlated with the amount of mixed-linkage glucan. CONCLUSIONS Three domains of glucuronoarabinoxylan were determined: one separating cellulose microfibrils, one interacting with them and a middle domain between the two, which links them. The middle domain is masked by the mixed-linkage glucan. A model is proposed in which the mixed-linkage glucan serves as a gel-like filler of the space between the separating domain of the glucuronoarabinoxylan and the cellulose microfibrils. Space for glucan is provided along the middle domain, the proportion of which increases during cell elongation.
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Affiliation(s)
- L V Kozlova
- Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Science, Kazan, Lobachevskij str., 2/31, 420111, Russia
| | - M V Ageeva
- Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Science, Kazan, Lobachevskij str., 2/31, 420111, Russia
| | - N N Ibragimova
- Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Science, Kazan, Lobachevskij str., 2/31, 420111, Russia
| | - T A Gorshkova
- Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Science, Kazan, Lobachevskij str., 2/31, 420111, Russia
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Hu G, Burton C, Hong Z. Molecular and Chemical Characterization of a New WaxyAllele in Barley ( Hordeum vulgareL.). Cereal Chem 2014. [DOI: 10.1094/cchem-10-13-0217-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Gongshe Hu
- U.S. Department of Agriculture, Agricultural Research Service, 1691 S. 2700 W., Aberdeen, ID 83210
- Corresponding author. Phone: (208) 397-4162. Fax: (208) 397-4165
| | - Charlotte Burton
- U.S. Department of Agriculture, Agricultural Research Service, 1691 S. 2700 W., Aberdeen, ID 83210
| | - Zonglie Hong
- Department of Plant, Soil, and Entomological Sciences, and Program of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow, ID 83844
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Kourmpetli S, Drea S. The fruit, the whole fruit, and everything about the fruit. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:4491-503. [PMID: 24723396 DOI: 10.1093/jxb/eru144] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Fruits come in an impressive array of shapes, sizes, and consistencies, and also display a huge diversity in biochemical/metabolite profiles, wherein lies their value as rich sources of food, nutrition, and pharmaceuticals. This is in addition to their fundamental function in supporting and dispersing the developing and mature seeds for the next generation. Understanding developmental processes such as fruit development and ripening, particularly at the genetic level, was once largely restricted to model and crop systems for practical and commercial reasons, but with the expansion of developmental genetic and evo-devo tools/analyses we can now investigate and compare aspects of fruit development in species spanning the angiosperms. We can superimpose recent genetic discoveries onto the detailed characterization of fruit development and ripening conducted with primary considerations such as yield and harvesting efficiency in mind, as well as on the detailed description of taxonomically relevant characters. Based on our own experience we focus on two very morphologically distinct and evolutionary distant fruits: the capsule of opium poppy, and the grain or caryopsis of cereals. Both are of massive economic value, but because of very different constituents; alkaloids of varied pharmaceutical value derived from secondary metabolism in opium poppy capsules, and calorific energy fuel derived from primary metabolism in cereal grains. Through comparative analyses in these and other fruit types, interesting patterns of regulatory gene function diversification and conservation are beginning to emerge.
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Affiliation(s)
- Sofia Kourmpetli
- Department of Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Sinéad Drea
- Department of Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
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Yin Y, Johns MA, Cao H, Rupani M. A survey of plant and algal genomes and transcriptomes reveals new insights into the evolution and function of the cellulose synthase superfamily. BMC Genomics 2014; 15:260. [PMID: 24708035 PMCID: PMC4023592 DOI: 10.1186/1471-2164-15-260] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 03/31/2014] [Indexed: 11/30/2022] Open
Abstract
Background Enzymes of the cellulose synthase (CesA) family and CesA-like (Csl) families are responsible for the synthesis of celluloses and hemicelluloses, and thus are of great interest to bioenergy research. We studied the occurrences and phylogenies of CesA/Csl families in diverse plants and algae by comprehensive data mining of 82 genomes and transcriptomes. Results We found that 1) charophytic green algae (CGA) have orthologous genes in CesA, CslC and CslD families; 2) liverwort genes are found in the CesA, CslA, CslC and CslD families; 3) The fern Pteridium aquilinum not only has orthologs in these conserved families but also in the CslB, CslH and CslE families; 4) basal angiosperms, e.g. Aristolochia fimbriata, have orthologs in these families too; 5) gymnosperms have genes forming clusters ancestral to CslB/H and to CslE/J/G respectively; 6) CslG is found in switchgrass and basal angiosperms; 7) CslJ is widely present in dicots and monocots; 8) CesA subfamilies have already diversified in ferns. Conclusions We speculate that: (i) ferns and horsetails might both have CslH enzymes, responsible for the synthesis of mixed-linkage glucans and (ii) CslD and similar genes might be responsible for the synthesis of mannans in CGA. Our findings led to a more detailed model of cell wall evolution and suggested that gene loss played an important role in the evolution of Csl families. We also demonstrated the usefulness of transcriptome data in the study of plant cell wall evolution and diversity.
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Affiliation(s)
- Yanbin Yin
- Department of Biological Sciences, Northern Illinois University, Montgomery Hall 325A, DeKalb, IL 60115-2857, USA.
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Hu G, Burton C, Hong Z, Jackson E. A mutation of the cellulose-synthase-like (CslF6) gene in barley (Hordeum vulgare L.) partially affects the β-glucan content in grains. J Cereal Sci 2014. [DOI: 10.1016/j.jcs.2013.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Plant Cell Wall Polysaccharides: Structure and Biosynthesis. POLYSACCHARIDES 2014. [DOI: 10.1007/978-3-319-03751-6_73-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Trafford K, Haleux P, Henderson M, Parker M, Shirley NJ, Tucker MR, Fincher GB, Burton RA. Grain development in Brachypodium and other grasses: possible interactions between cell expansion, starch deposition, and cell-wall synthesis. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:5033-5047. [PMID: 24052531 DOI: 10.1093/jxb/ert292] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
To explain the low levels of starch, high levels of (1,3;1,4)-β-glucan, and thick cell walls in grains of Brachypodium distachyon L. relative to those in other Pooideae, aspects of grain development were compared between B. distachyon and barley (Hordeum vulgare L.). Cell proliferation, cell expansion, and endoreduplication were reduced in B. distachyon relative to barley and, consistent with these changes, transcriptional downregulation of the cell-cycle genes CDKB1 and cyclin A3 was observed. Similarly, reduced transcription of starch synthase I and starch-branching enzyme I was observed as well as reduced activity of starch synthase and ADP-glucose pyrophosphorylase, which are consistent with the lowered starch content in B. distachyon grains. No change was detected in transcription of the major gene involved in (1,3;1,4)-β-glucan synthesis, cellulose synthase-like F6. These results suggest that, while low starch content results from a reduced capacity for starch synthesis, the unusually thick cell walls in B. distachyon endosperm probably result from continuing (1,3;1,4)-β-glucan deposition in endosperm cells that fail to expand. This raises the possibility that endosperm expansion is linked to starch deposition.
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Affiliation(s)
- Kay Trafford
- National Institute of Agricultural Botany, Huntingdon Road, Cambridge CB3 0LE, UK
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Giannoutsou E, Sotiriou P, Apostolakos P, Galatis B. Early local differentiation of the cell wall matrix defines the contact sites in lobed mesophyll cells of Zea mays. ANNALS OF BOTANY 2013; 112:1067-81. [PMID: 23969761 PMCID: PMC3783239 DOI: 10.1093/aob/mct175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/12/2013] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND AIMS The morphogenesis of lobed mesophyll cells (MCs) is highly controlled and coupled with intercellular space formation. Cortical microtubule rings define the number and the position of MC isthmi. This work investigated early events of MC morphogenesis, especially the mechanism defining the position of contacts between MCs. The distributions of plasmodesmata, the hemicelluloses callose and (1 → 3,1 → 4)-β-d-glucans (MLGs) and the pectin epitopes recognized by the 2F4, JIM5, JIM7 and LM6 antibodies were studied in the cell walls of Zea mays MCs. METHODS Matrix cell wall polysaccharides were immunolocalized in hand-made sections and in sections of material embedded in LR White resin. Callose was also localized using aniline blue in hand-made sections. Plasmodesmata distribution was examined by transmission electron microscopy. RESULTS Before reorganization of the dispersed cortical microtubules into microtubule rings, particular bands of the longitudinal MC walls, where the MC contacts will form, locally differentiate by selective (1) deposition of callose and the pectin epitopes recognized by the 2F4, LM6, JIM5 and JIM7 antibodies, (2) degradation of MLGs and (3) formation of secondary plasmodesmata clusterings. This cell wall matrix differentiation persists in cell contacts of mature MCs. Simultaneously, the wall bands between those of future cell contacts differentiate with (1) deposition of local cell wall thickenings including cellulose microfibrils, (2) preferential presence of MLGs, (3) absence of callose and (4) transient presence of the pectins identified by the JIM5 and JIM7 antibodies. The wall areas between cell contacts expand determinately to form the cell isthmi and the cell lobes. CONCLUSIONS The morphogenesis of lobed MCs is characterized by the early patterned differentiation of two distinct cell wall subdomains, defining the sites of the future MC contacts and of the future MC isthmi respectively. This patterned cell wall differentiation precedes cortical microtubule reorganization and may define microtubule ring disposition.
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Affiliation(s)
| | | | | | - B. Galatis
- Department of Botany, Faculty of Biology, University of Athens, Athens 15784, Greece
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Wang Y, Chantreau M, Sibout R, Hawkins S. Plant cell wall lignification and monolignol metabolism. FRONTIERS IN PLANT SCIENCE 2013; 4:220. [PMID: 23847630 PMCID: PMC3705174 DOI: 10.3389/fpls.2013.00220] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 06/06/2013] [Indexed: 05/18/2023]
Abstract
Plants are built of various specialized cell types that differ in their cell wall composition and structure. The cell walls of certain tissues (xylem, sclerenchyma) are characterized by the presence of the heterogeneous lignin polymer that plays an essential role in their physiology. This phenolic polymer is composed of different monomeric units - the monolignols - that are linked together by several covalent bonds. Numerous studies have shown that monolignol biosynthesis and polymerization to form lignin are tightly controlled in different cell types and tissues. However, our understanding of the genetic control of monolignol transport and polymerization remains incomplete, despite some recent promising results. This situation is made more complex since we know that monolignols or related compounds are sometimes produced in non-lignified tissues. In this review, we focus on some key steps of monolignol metabolism including polymerization, transport, and compartmentation. As well as being of fundamental interest, the quantity of lignin and its nature are also known to have a negative effect on the industrial processing of plant lignocellulose biomass. A more complete view of monolignol metabolism and the relationship that exists between lignin and other monolignol-derived compounds thereby appears essential if we wish to improve biomass quality.
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Affiliation(s)
- Yin Wang
- Unite Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, Saclay Plant SciencesVersailles, France
| | - Maxime Chantreau
- Lille 1 UMR 1281, UniversitéLille Nord de FranceVilleneuve d’Ascq, France
- Unite Mixte de Recherche 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Institut National de la Recherche AgronomiqueVilleneuve d’Ascq, France
| | - Richard Sibout
- Unite Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, Saclay Plant SciencesVersailles, France
| | - Simon Hawkins
- Lille 1 UMR 1281, UniversitéLille Nord de FranceVilleneuve d’Ascq, France
- Unite Mixte de Recherche 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Institut National de la Recherche AgronomiqueVilleneuve d’Ascq, France
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Newell MA, Asoro FG, Scott MP, White PJ, Beavis WD, Jannink JL. Genome-wide association study for oat (Avena sativa L.) beta-glucan concentration using germplasm of worldwide origin. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2012; 125:1687-96. [PMID: 22865125 DOI: 10.1007/s00122-012-1945-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 07/15/2012] [Indexed: 05/18/2023]
Abstract
Detection of quantitative trait loci (QTL) controlling complex traits followed by selection has become a common approach for selection in crop plants. The QTL are most often identified by linkage mapping using experimental F(2), backcross, advanced inbred, or doubled haploid families. An alternative approach for QTL detection are genome-wide association studies (GWAS) that use pre-existing lines such as those found in breeding programs. We explored the implementation of GWAS in oat (Avena sativa L.) to identify QTL affecting β-glucan concentration, a soluble dietary fiber with several human health benefits when consumed as a whole grain. A total of 431 lines of worldwide origin were tested over 2 years and genotyped using Diversity Array Technology (DArT) markers. A mixed model approach was used where both population structure fixed effects and pair-wise kinship random effects were included. Various mixed models that differed with respect to population structure and kinship were tested for their ability to control for false positives. As expected, given the level of population structure previously described in oat, population structure did not play a large role in controlling for false positives. Three independent markers were significantly associated with β-glucan concentration. Significant marker sequences were compared with rice and one of the three showed sequence homology to genes localized on rice chromosome seven adjacent to the CslF gene family, known to have β-glucan synthase function. Results indicate that GWAS in oat can be a successful option for QTL detection, more so with future development of higher-density markers.
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Affiliation(s)
- Mark A Newell
- The Samuel Roberts Noble Foundation, Ardmore, OK 73401, USA.
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Vega-Sánchez ME, Verhertbruggen Y, Christensen U, Chen X, Sharma V, Varanasi P, Jobling SA, Talbot M, White RG, Joo M, Singh S, Auer M, Scheller HV, Ronald PC. Loss of Cellulose synthase-like F6 function affects mixed-linkage glucan deposition, cell wall mechanical properties, and defense responses in vegetative tissues of rice. PLANT PHYSIOLOGY 2012; 159:56-69. [PMID: 22388489 PMCID: PMC3375985 DOI: 10.1104/pp.112.195495] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 02/29/2012] [Indexed: 05/17/2023]
Abstract
Mixed-linkage glucan (MLG) is a cell wall polysaccharide containing a backbone of unbranched (1,3)- and (1,4)-linked β-glucosyl residues. Based on its occurrence in plants and chemical characteristics, MLG has primarily been associated with the regulation of cell wall expansion due to its high and transient accumulation in young, expanding tissues. The Cellulose synthase-like F (CslF) subfamily of glycosyltransferases has previously been implicated in mediating the biosynthesis of this polymer. We confirmed that the rice (Oryza sativa) CslF6 gene mediates the biosynthesis of MLG by overexpressing it in Nicotiana benthamiana. Rice cslf6 knockout mutants show a slight decrease in height and stem diameter but otherwise grew normally during vegetative development. However, cslf6 mutants display a drastic decrease in MLG content (97% reduction in coleoptiles and virtually undetectable in other tissues). Immunodetection with an anti-MLG monoclonal antibody revealed that the coleoptiles and leaves retain trace amounts of MLG only in specific cell types such as sclerenchyma fibers. These results correlate with the absence of endogenous MLG synthase activity in mutant seedlings and 4-week-old sheaths. Mutant cell walls are weaker in mature stems but not seedlings, and more brittle in both stems and seedlings, compared to wild type. Mutants also display lesion mimic phenotypes in leaves, which correlates with enhanced defense-related gene expression and enhanced disease resistance. Taken together, our results underline a weaker role of MLG in cell expansion than previously thought, and highlight a structural role for MLG in nonexpanding, mature stem tissues in rice.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Pamela C. Ronald
- Joint BioEnergy Institute, Emeryville, California 94608 (M.E.V.-S., Y.V., U.C., X.C., V.S., P.V., M.J., S.S., M.A., H.V.S., P.C.R.); Divisions of Physical Biosciences (Y.V., U.C., V.S., H.V.S., P.C.R.) and Life Sciences (M.J., M.A.), Lawrence Berkeley National Laboratory, Berkeley, California 94720; Commonwealth Scientific and Industrial Research Organization Food Futures Flagship (S.A.J., M.T., R.G.W.) and Commonwealth Scientific and Industrial Research Organization Plant Industry (S.A.J.), Black Mountain Laboratories, Black Mountain, Australian Capital Territory 2601, Australia; Department of Plant Pathology (M.E.V.-S., X.C., P.C.R.) and The Genome Center (P.C.R.), University of California, Davis, California 95616; Biomass Science and Conversion Technologies Department, Sandia National Laboratories, Livermore, California 94551 (P.V., S.S.); and Department of Plant Molecular System Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin 446–701, Korea (P.C.R.)
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Effect of genotype, environment and agronomic management on β-glucan concentration of naked barley grain intended for health food use. J Cereal Sci 2011. [DOI: 10.1016/j.jcs.2011.02.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Burton RA, Collins HM, Kibble NAJ, Smith JA, Shirley NJ, Jobling SA, Henderson M, Singh RR, Pettolino F, Wilson SM, Bird AR, Topping DL, Bacic A, Fincher GB. Over-expression of specific HvCslF cellulose synthase-like genes in transgenic barley increases the levels of cell wall (1,3;1,4)-β-d-glucans and alters their fine structure. PLANT BIOTECHNOLOGY JOURNAL 2011; 9:117-35. [PMID: 20497371 DOI: 10.1111/j.1467-7652.2010.00532.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Cell walls in commercially important cereals and grasses are characterized by the presence of (1,3;1,4)-β-d-glucans. These polysaccharides are beneficial constituents of human diets, where they can reduce the risk of hypercholesterolemia, type II diabetes, obesity and colorectal cancer. The biosynthesis of cell wall (1,3;1,4)-β-d-glucans in the Poaceae is mediated, in part at least, by the cellulose synthase-like CslF family of genes. Over-expression of the barley CslF6 gene under the control of an endosperm-specific oat globulin promoter results in increases of more than 80% in (1,3;1,4)-β-d-glucan content in grain of transgenic barley. Analyses of (1,3;1,4)-β-d-glucan fine structure indicate that individual CslF enzymes might direct the synthesis of (1,3;1,4)-β-d-glucans with different structures. When expression of the CslF6 transgene is driven by the Pro35S promoter, the transgenic lines have up to sixfold higher levels of (1,3;1,4)-β-d-glucan in leaves, but similar levels as controls in the grain. Some transgenic lines of Pro35S:CslF4 also show increased levels of (1,3;1,4)-β-d-glucans in grain, but not in leaves. Thus, the effects of CslF genes on (1,3;1,4)-β-d-glucan levels are dependent not only on the promoter used, but also on the specific member of the CslF gene family that is inserted into the transgenic barley lines. Altering (1,3;1,4)-β-d-glucan levels in grain and vegetative tissues will have potential applications in human health, where (1,3;1,4)-β-d-glucans contribute to dietary fibre, and in tailoring the composition of biomass cell walls for the production of bioethanol from cereal crop residues and grasses.
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Affiliation(s)
- Rachel A Burton
- School of Agriculture, Food and Wine, and the Australian Centre for Plant Functional Genomics, University of Adelaide, Glen Osmond, SA, Australia
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