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Pourmohammadi K, Abedi E, Hashemi SMB. Gliadin and glutenin genomes and their effects on the technological aspect of wheat-based products. Curr Res Food Sci 2023; 7:100622. [PMID: 38021258 PMCID: PMC10643115 DOI: 10.1016/j.crfs.2023.100622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/09/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023] Open
Abstract
Wheat is the most important crops worldwide, providing about one-fifth of the daily protein and calories for human consumption. The quality of cereal-based products is principally governed by the genetic basis of gluten (glutenin and gliadin proteins), which exists in a wide range of variable alleles and is controlled by clusters of genes. There are certain limitations associated with gluten characteristics, which can be genetically manipulated. The present review aimed to investigate the correlation between the genetic characteristics of gluten protein components and wheat-based product's quality. According to various references, Glu-B1d (6 + 8), Glu-B1h (14 + 15) and Glu-B1b (7 + 8) are related to higher gluten strength and pasta quality, while, subunits Dx2 + Dy12 and Dx5 + Dy10, are usually present at the Glu-D1 locus in bread wheat, resulted in lower cooked firmness in pasta. Moreover, introducing Gli-D1/Glu-D3 and Glu-D1 loci into durum wheat genomes, causing to provide the maximum values of gluten index in pasta products. 1Dx5 + 1Dy10 alleles determine the level of increase in dough's consistency, elasticity, viscosity, and extensibility quality of baking and appropriate bread loaf volume, while 1Dx2 + 1Dy12 as the alleles associated with poor baking quality, being more suitable for soft wheat/pastry end uses. Bx7, Bx7OE, 1Bx17 + 1By18, 1Bx13 + 1By16, Bx7 + By9 and 1Bx7 + 1By8 at Glu-B1alleles and 1Ax2* found on Glu-A1, augmented dough strength and has positive effects on consistency, extensibility, viscosity, and elasticity of bread dough. Breeding programs by genome editing have made gluten a promoting component for improving cereal-based products.
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Affiliation(s)
- Kiana Pourmohammadi
- Department of Food Science and Technology, Faculty of Agriculture, Fasa University, Fasa, Iran
| | - Elahe Abedi
- Department of Food Science and Technology, Faculty of Agriculture, Fasa University, Fasa, Iran
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2
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Peirats-Llobet M, Yi C, Liew L, Berkowitz O, Narsai R, Lewsey M, Whelan J. Spatially resolved transcriptomic analysis of the germinating barley grain. Nucleic Acids Res 2023; 51:7798-7819. [PMID: 37351575 PMCID: PMC10450182 DOI: 10.1093/nar/gkad521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/26/2023] [Accepted: 06/03/2023] [Indexed: 06/24/2023] Open
Abstract
Seeds are a vital source of calories for humans and a unique stage in the life cycle of flowering plants. During seed germination, the embryo undergoes major developmental transitions to become a seedling. Studying gene expression in individual seed cell types has been challenging due to the lack of spatial information or low throughput of existing methods. To overcome these limitations, a spatial transcriptomics workflow was developed for germinating barley grain. This approach enabled high-throughput analysis of spatial gene expression, revealing specific spatial expression patterns of various functional gene categories at a sub-tissue level. This study revealed over 14 000 genes differentially regulated during the first 24 h after imbibition. Individual genes, such as the aquaporin gene family, starch degradation, cell wall modification, transport processes, ribosomal proteins and transcription factors, were found to have specific spatial expression patterns over time. Using spatial autocorrelation algorithms, we identified auxin transport genes that had increasingly focused expression within subdomains of the embryo over time, suggesting their role in establishing the embryo axis. Overall, our study provides an unprecedented spatially resolved cellular map for barley germination and identifies specific functional genomics targets to better understand cellular restricted processes during germination. The data can be viewed at https://spatial.latrobe.edu.au/.
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Affiliation(s)
- Marta Peirats-Llobet
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Changyu Yi
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Lim Chee Liew
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Oliver Berkowitz
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Reena Narsai
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Mathew G Lewsey
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - James Whelan
- Department of Animal, Plant and Soil Science, La Trobe Institute for Sustainable Agriculture and Food, School of Agriculture, Biomedical and Environmental Sciences, La Trobe University, Bundoora, Victoria 3086, Australia
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
- Research Centre for Engineering Biology, College of Life Science, Zhejiang University, 718 East Haizhou Road, Haining, Jiaxing, Zhejiang 314400, China
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Gao Y, Liu Q. A new target for improving wheat end-use quality. THE NEW PHYTOLOGIST 2023. [PMID: 37182221 DOI: 10.1111/nph.18889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Affiliation(s)
- Yujiao Gao
- Jiangsu Key Lab of Crop Genomics and Molecular Breeding, College of Agriculture, Yangzhou University, Yangzhou, 225009, China
| | - Qiaoquan Liu
- Jiangsu Key Lab of Crop Genomics and Molecular Breeding, College of Agriculture, Yangzhou University, Yangzhou, 225009, China
- Hainan Yazhou Bay Seed Laboratory, Sanya, 572024, China
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Bacala R, Hatcher DW, Perreault H, Fu BX. Challenges and opportunities for proteomics and the improvement of bread wheat quality. JOURNAL OF PLANT PHYSIOLOGY 2022; 275:153743. [PMID: 35749977 DOI: 10.1016/j.jplph.2022.153743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/13/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Wheat remains a critical global food source, pressured by climate change and the need to maximize yield, improve processing and nutritional quality and ensure safety. An enormous amount of research has been conducted to understand gluten protein composition and structure in relation to end-use quality, yet progress has become stagnant. This is mainly due to the need and inability to biochemically characterize the intact functional glutenin polymer in order to correlate to quality, necessitating reduction to monomeric subunits and a loss of contextual information. While some individual gluten proteins might have a positive or negative influence on gluten quality, it is the sum total of these proteins, their relative and absolute expression, their sub-cellular trafficking, the amount and size of glutenin polymers, and ratios between gluten protein classes that define viscoelasticity of gluten. The sub-cellular trafficking of gluten proteins during seed maturation is still not completely clear and there is evidence of dual pathways and therefore different destinations for proteins, either constitutively or temporally. The trafficking of proteins is also unclear in endosperm cells as they undergo programmed cell death; Golgi disappear around 12 DPA but protein filling continues at least to 25 DPA. Modulation of the timing of cellular events will invariably affect protein deposition and therefore gluten strength and function. Existing and emerging proteomics technologies such as proteoform profiling and top-down proteomics offer new tools to study gluten protein composition as a whole system and identify compositional patterns that can modify gluten structure with improved functionality.
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Affiliation(s)
- Ray Bacala
- Canadian Grain Commission, Grain Research Laboratory, 1404-303 Main Street, Winnipeg, Manitoba, R3C 3G8, Canada; University of Manitoba, Department of Chemistry, 144 Dysart Road, Winnipeg, Manitoba, R3T 2N2, Canada.
| | - Dave W Hatcher
- Canadian Grain Commission, Grain Research Laboratory, 1404-303 Main Street, Winnipeg, Manitoba, R3C 3G8, Canada
| | - Héléne Perreault
- University of Manitoba, Department of Chemistry, 144 Dysart Road, Winnipeg, Manitoba, R3T 2N2, Canada.
| | - Bin Xiao Fu
- Canadian Grain Commission, Grain Research Laboratory, 1404-303 Main Street, Winnipeg, Manitoba, R3C 3G8, Canada; Department of Food and Human Nutritional Sciences, 209 - 35 Chancellor's Circle, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
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Lafiandra D, Shewry PR. Wheat Glutenin polymers 2, the role of wheat glutenin subunits in polymer formation and dough quality. J Cereal Sci 2022. [DOI: 10.1016/j.jcs.2022.103487] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Wen N, Osorio CE, Brew-Appiah RAT, Mejías JH, Alam T, Kashyap S, Reinbothe S, Reinbothe C, Moehs CP, von Wettstein D, Rustgi S. Targeting Induced Local Lesions in the Wheat DEMETER and DRE2 Genes, Responsible for Transcriptional Derepression of Wheat Gluten Proteins in the Developing Endosperm. Front Nutr 2022; 9:847635. [PMID: 35308262 PMCID: PMC8928260 DOI: 10.3389/fnut.2022.847635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 01/28/2022] [Indexed: 01/05/2023] Open
Abstract
Wheat is a major source of energy and nutrition worldwide, but it is also a primary cause of frequent diet-induced health issues, specifically celiac disease, for which the only effective therapy so far is strict dietary abstinence from gluten-containing grains. Wheat gluten proteins are grouped into two major categories: high-molecular-weight glutenin subunits (HMWgs), vital for mixing and baking properties, and gliadins plus low-molecular-weight glutenin subunits (LMWgs) that contain the overwhelming majority of celiac-causing epitopes. We put forth a hypothesis that eliminating gliadins and LMWgs while retaining HMWgs might allow the development of reduced-immunogenicity wheat genotypes relevant to most gluten-sensitive individuals. This hypothesis stems from the knowledge that the molecular structures and regulatory mechanisms of the genes encoding the two groups of gluten proteins are quite different, and blocking one group's transcription, without affecting the other's, is possible. The genes for gliadins and LMWgs have to be de-methylated by 5-methylcytosine DNA glycosylase/lyase (DEMETER) and an iron-sulfur (Fe-S) cluster biogenesis enzyme (DRE2) early during endosperm development to permit their transcription. In this study, a TILLING (Targeting Induced Local Lesions IN Genomes) approach was undertaken to identify mutations in the homoeologous DEMETER (DME) and DRE2 genes in common and durum wheat. Lines with mutations in these genes were obtained that displayed reduced content of immunogenic gluten proteins while retaining essential baking properties. Although our data at first glance suggest new possibilities for treating celiac disease and are therefore of medical and agronomical interest, it also shows that inducing mutations in the DME and DRE2 genes analyzed here affected pollen viability and germination. Hence there is a need to develop other approaches in the future to overcome this undesired effect.
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Affiliation(s)
- Nuan Wen
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
| | - Claudia E. Osorio
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
- Instituto de Investigaciones Agropecuarias, INIA Carillanca, Temuco, Chile
| | - Rhoda A. T. Brew-Appiah
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
| | - Jaime H. Mejías
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
- Instituto de Investigaciones Agropecuarias, INIA Carillanca, Temuco, Chile
| | - Tariq Alam
- Department of Plant and Environmental Sciences, School of Health Research, Clemson University Pee Dee Research and Education Centre, Florence, SC, United States
| | - Samneet Kashyap
- Department of Plant and Environmental Sciences, School of Health Research, Clemson University Pee Dee Research and Education Centre, Florence, SC, United States
| | - Steffen Reinbothe
- Laboratoire de Génétique Moléculaire des Plantes, Université Grenoble-Alpes, BP53F, Grenoble, France
| | - Christiane Reinbothe
- Laboratoire de Génétique Moléculaire des Plantes, Université Grenoble-Alpes, BP53F, Grenoble, France
| | | | - Diter von Wettstein
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
| | - Sachin Rustgi
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
- Department of Plant and Environmental Sciences, School of Health Research, Clemson University Pee Dee Research and Education Centre, Florence, SC, United States
- *Correspondence: Sachin Rustgi
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Zhou Z, Liu C, Qin M, Li W, Hou J, Shi X, Dai Z, Yao W, Tian B, Lei Z, Li Y, Wu Z. Promoter DNA hypermethylation of TaGli-γ-2.1 positively regulates gluten strength in bread wheat. J Adv Res 2022; 36:163-173. [PMID: 35127171 PMCID: PMC8799914 DOI: 10.1016/j.jare.2021.06.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 06/11/2021] [Accepted: 06/28/2021] [Indexed: 12/30/2022] Open
Abstract
TaGli-γ-2.1 belonged to a subgroup of γ-gliadin multigene family. TaGli-γ-2.1 was a negative regulatory factor in gluten strength. Methylation of pTaGli-γ-2.1 played a key role in regulating TaGli-γ-2.1 expression. Lower γ-gliadin content followed with hypermethylation of pTaGli-γ-2.1. Decreasing TaGli-γ-2.1 expression could be used to improve gluten strength in wheat breeding.
Introduction Gliadins are the major components of gluten proteins with vital roles on properties of end-use wheat product and health-relate quality of wheat. However, the function and regulation mechanisms of γ-gliadin genes remain unclear. Objectives Dissect the effect of DNA methylation in the promoter of γ-gliadin gene on its expression level and gluten strength of wheat. Methods The prokaryotic expression and reduction–oxidation reactions were performed to identify the effect of TaGli-γ-2.1 on dough strength. Bisulfite analysis and 5-Aza-2′-deoxycytidine treatment were used to verify the regulation of TaGli-γ-2.1 expression by pTaGli-γ-2.1 methylation. The content of gluten proteins composition was measured by RP-HPLC, and the gluten strength was measured by Gluten Index and Farinograph. Results TaGli-γ-2.1 was classified into a subgroup of γ-gliadin multigene family and was preferentially expressed in the later period of grain filling. Addition of TaGli-γ-2.1 protein fragment into strong gluten wheat flour significantly decreased the stability time. Hypermethylation of three CG loci of pTaGli-γ-2.1 conferred to lower TaGli-γ-2.1 expression. Treatment with 5-Aza-2′-deoxycytidine in seeds of strong gluten wheat varieties increased the expression levels of TaGli-γ-2.1. Furthermore, the accumulations of gliadin and γ-gliadin were significantly decreased in hypermethylated wheat varieties, corresponding with the increasing of gluten index and dough stability time. Conclusion Epigenetic modification of pTaGli-γ-2.1 affected gluten strength by modulating the proportion of gluten proteins. Hypermethylation of pTaGli-γ-2.1 is a novel genetic resource for enhancing gluten strength in wheat quality breeding.
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Affiliation(s)
- Zhengfu Zhou
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
- Agronomy College, Zhengzhou University, Zhengzhou 450001, China
| | - Congcong Liu
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
- National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou 450002, China
| | - Maomao Qin
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
| | - Wenxu Li
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
| | - Jinna Hou
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
| | - Xia Shi
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
| | - Ziju Dai
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
| | - Wen Yao
- National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou 450002, China
| | - Baoming Tian
- Agronomy College, Zhengzhou University, Zhengzhou 450001, China
| | - Zhensheng Lei
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
- National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou 450002, China
- Agronomy College, Zhengzhou University, Zhengzhou 450001, China
| | - Yang Li
- National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou 450002, China
| | - Zhengqing Wu
- Henan Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
- Agronomy College, Zhengzhou University, Zhengzhou 450001, China
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Paris R, Petruzzino G, Savino M, De Simone V, Ficco DBM, Trono D. Genome-Wide Identification, Characterization and Expression Pattern Analysis of the γ-Gliadin Gene Family in the Durum Wheat ( Triticum durum Desf.) Cultivar Svevo. Genes (Basel) 2021; 12:genes12111743. [PMID: 34828349 PMCID: PMC8621147 DOI: 10.3390/genes12111743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/26/2021] [Accepted: 10/28/2021] [Indexed: 02/07/2023] Open
Abstract
Very recently, the genome of the modern durum wheat cv. Svevo was fully sequenced, and its assembly is publicly available. So, we exploited the opportunity to carry out an in-depth study for the systematic characterization of the γ-gliadin gene family in the cv. Svevo by combining a bioinformatic approach with transcript and protein analysis. We found that the γ-gliadin family consists of nine genes that include seven functional genes and two pseudogenes. Three genes, Gli-γ1a, Gli-γ3a and Gli-γ4a, and the pseudogene Gli-γ2a* mapped on the A genome, whereas the remaining four genes, Gli-γ1b, Gli-γ2b, Gli-γ3b and Gli-γ5b, and the pseudogene Gli-γ4b* mapped on the B genome. The functional γ-gliadins presented all six domains and eight-cysteine residues typical of γ-gliadins. The Gli-γ1b also presented an additional cysteine that could possibly have a role in the formation of the gluten network through binding to HMW glutenins. The γ-gliadins from the A and B genome differed in their celiac disease (CD) epitope content and composition, with the γ-gliadins from the B genome showing the highest frequency of CD epitopes. In all the cases, almost all the CD epitopes clustered in the central region of the γ-gliadin proteins. Transcript analysis during seed development revealed that all the functional γ-gliadin genes were expressed with a similar pattern, although significant differences in the transcript levels were observed among individual genes that were sometimes more than 60-fold. A progressive accumulation of the γ-gliadin fraction was observed in the ripening seeds that reached 34% of the total gliadin fraction at harvest maturity. We believe that the insights generated in the present study could aid further studies on gliadin protein functions and future breeding programs aimed at the selection of new healthier durum wheat genotypes.
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Affiliation(s)
- Roberta Paris
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Centro di Ricerca Cerealicoltura e Colture Industriali, Via di Corticella 133, 40128 Bologna, Italy;
| | - Giuseppe Petruzzino
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Centro di Ricerca Cerealicoltura e Colture Industriali, S.S. 673, Km 25,200, 71122 Foggia, Italy; (G.P.); (M.S.); (V.D.S.); (D.B.M.F.)
| | - Michele Savino
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Centro di Ricerca Cerealicoltura e Colture Industriali, S.S. 673, Km 25,200, 71122 Foggia, Italy; (G.P.); (M.S.); (V.D.S.); (D.B.M.F.)
| | - Vanessa De Simone
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Centro di Ricerca Cerealicoltura e Colture Industriali, S.S. 673, Km 25,200, 71122 Foggia, Italy; (G.P.); (M.S.); (V.D.S.); (D.B.M.F.)
| | - Donatella B. M. Ficco
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Centro di Ricerca Cerealicoltura e Colture Industriali, S.S. 673, Km 25,200, 71122 Foggia, Italy; (G.P.); (M.S.); (V.D.S.); (D.B.M.F.)
| | - Daniela Trono
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Centro di Ricerca Cerealicoltura e Colture Industriali, S.S. 673, Km 25,200, 71122 Foggia, Italy; (G.P.); (M.S.); (V.D.S.); (D.B.M.F.)
- Correspondence:
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Metakovsky E, Pascual L, Vaccino P, Melnik V, Rodriguez-Quijano M, Popovych Y, Chebotar S, Rogers WJ. Heteroalleles in Common Wheat: Multiple Differences between Allelic Variants of the Gli-B1 Locus. Int J Mol Sci 2021; 22:ijms22041832. [PMID: 33673225 PMCID: PMC7917834 DOI: 10.3390/ijms22041832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/30/2021] [Accepted: 02/07/2021] [Indexed: 11/21/2022] Open
Abstract
The Gli-B1-encoded γ-gliadins and non-coding γ-gliadin DNA sequences for 15 different alleles of common wheat have been compared using seven tests: electrophoretic mobility (EM) and molecular weight (MW) of the encoded major γ-gliadin, restriction fragment length polymorphism patterns (RFLPs) (three different markers), Gli-B1-γ-gliadin-pseudogene known SNP markers (Single nucleotide polymorphisms) and sequencing the pseudogene GAG56B. It was discovered that encoded γ-gliadins, with contrasting EM, had similar MWs. However, seven allelic variants (designated from I to VII) differed among them in the other six tests: I (alleles Gli-B1i, k, m, o), II (Gli-B1n, q, s), III (Gli-B1b), IV (Gli-B1e, f, g), V (Gli-B1h), VI (Gli-B1d) and VII (Gli-B1a). Allele Gli-B1c (variant VIII) was identical to the alleles from group IV in four of the tests. Some tests might show a fine difference between alleles belonging to the same variant. Our results attest in favor of the independent origin of at least seven variants at the Gli-B1 locus that might originate from deeply diverged genotypes of the donor(s) of the B genome in hexaploid wheat and therefore might be called “heteroallelic”. The donor’s particularities at the Gli-B1 locus might be conserved since that time and decisively contribute to the current high genetic diversity of common wheat.
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Affiliation(s)
- Eugene Metakovsky
- Department of Biotechnology-Plant Biology, School of Agricultural, Food and Biosystems Engineering, Universidad Politécnica de Madrid, 28040 Madrid, Spain; (E.M.); (M.R.-Q.)
| | - Laura Pascual
- Department of Biotechnology-Plant Biology, School of Agricultural, Food and Biosystems Engineering, Universidad Politécnica de Madrid, 28040 Madrid, Spain; (E.M.); (M.R.-Q.)
- Correspondence:
| | - Patrizia Vaccino
- Consiglio per la Recerca in Agricultura e l’Analisi dell’Economia Agraria, Research Centre for Cereal and Industrial Crops, 13100 Vercelli, Italy;
| | - Viktor Melnik
- Vavilov Institute of General Genetics RAS, 117971 Moscow, Russia;
| | - Marta Rodriguez-Quijano
- Department of Biotechnology-Plant Biology, School of Agricultural, Food and Biosystems Engineering, Universidad Politécnica de Madrid, 28040 Madrid, Spain; (E.M.); (M.R.-Q.)
| | - Yulia Popovych
- Department of Genetics and Molecular Biology, National I.I. Mechnikov University, 65058 Odessa, Ukraine; (Y.P.); (S.C.)
| | - Sabina Chebotar
- Department of Genetics and Molecular Biology, National I.I. Mechnikov University, 65058 Odessa, Ukraine; (Y.P.); (S.C.)
| | - William John Rogers
- Departamento de Biología Aplicada, CIISAS, CIC-BIOLAB, CONICET-INBIOTEC, CRESCA, Facultad de Agronomía, Universidad Nacional del Centro de la Provincia Buenos Aires, 7300 Azul, Provincia de Buenos Aires, Argentina;
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Muhammad I, Li K, Shuaib M, Inamullah, Ayub M, Shafqat N, Alam B, Romman M, Azam N. Identification of biotic stress tolerant wheat germplasm using morphological and molecular approaches. GENE REPORTS 2020. [DOI: 10.1016/j.genrep.2020.100928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Mehanna MM, Mneimneh AT. Updated but not outdated “Gliadin”: A plant protein in advanced pharmaceutical nanotechnologies. Int J Pharm 2020; 587:119672. [DOI: 10.1016/j.ijpharm.2020.119672] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/03/2020] [Accepted: 07/16/2020] [Indexed: 02/06/2023]
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12
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Rustgi S, Shewry P, Brouns F, Deleu LJ, Delcour JA. Wheat Seed Proteins: Factors Influencing Their Content, Composition, and Technological Properties, and Strategies to Reduce Adverse Reactions. Compr Rev Food Sci Food Saf 2019; 18:1751-1769. [PMID: 33336954 DOI: 10.1111/1541-4337.12493] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 06/16/2019] [Accepted: 07/10/2019] [Indexed: 02/06/2023]
Abstract
Wheat is the primary source of nutrition for many, especially those living in developing countries, and wheat proteins are among the most widely consumed dietary proteins in the world. However, concerns about disorders related to the consumption of wheat and/or wheat gluten proteins have increased sharply in the last 20 years. This review focuses on wheat gluten proteins and amylase trypsin inhibitors, which are considered to be responsible for eliciting most of the intestinal and extraintestinal symptoms experienced by susceptible individuals. Although several approaches have been proposed to reduce the exposure to gluten or immunogenic peptides resulting from its digestion, none have proven sufficiently effective for general use in coeliac-safe diets. Potential approaches to manipulate the content, composition, and technological properties of wheat proteins are therefore discussed, as well as the effects of using gluten isolates in various food systems. Finally, some aspects of the use of gluten-free commodities are discussed.
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Affiliation(s)
- Sachin Rustgi
- Dept. of Plant and Environmental Sciences, School of Health Research, Clemson Univ. Pee Dee Research and Education Centre, Florence, SC, U.S.A.,Dept. of Crop and Soil Sciences, Washington State Univ., Pullman, WA, U.S.A
| | - Peter Shewry
- Rothamsted Research, Harpenden, Hertfordshire, U.K
| | - Fred Brouns
- Dept. of Human Biology, School of Nutrition and Translational Research in Metabolism, Faculty of Health, Medicine and Life Sciences, Maastricht Univ., Universiteitssingel 50, 6200, MD, Maastricht, the Netherlands
| | - Lomme J Deleu
- Laboratory of Food Chemistry and Biochemistry, Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001, Leuven, Belgium
| | - Jan A Delcour
- Laboratory of Food Chemistry and Biochemistry, Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001, Leuven, Belgium
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13
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Abstract
Wheat gluten has an immense impact on human nutrition as it largely determines the processing properties of wheat flour, and in particular the ability to make leavened breads, other baked products, pasta and noodles. However, there has been increasing interest in wheat gluten over the past two decades because of its well-established role in triggering coeliac disease, and its perceived role in other adverse reactions to wheat. The literature on wheat gluten is vast and extends back over two centuries, with most studies focusing on the structures of gluten proteins and their role in determining the functional properties of wheat flour and dough. This article provides a concise account of wheat gluten, focusing on properties, and features which are relevant to its role in triggering coeliac disease and, to a lesser extent, other gluten-related disorders. It includes descriptions of the biological role of the gluten proteins, the structures and relationships of gluten protein families, and the presence of related types of protein which may also contribute to functional properties and impacts on health. It therefore provides an understanding of the gluten protein system at the level required by those focusing on its impact on human health.
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Affiliation(s)
- Peter Shewry
- Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
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14
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Xu Y, Sun FY, Ji C, Hu QW, Wang CY, Wu DX, Sun G. Nucleotide diversity patterns at the DREB1 transcriptional factor gene in the genome donor species of wheat (Triticum aestivum L). PLoS One 2019; 14:e0217081. [PMID: 31136598 PMCID: PMC6538315 DOI: 10.1371/journal.pone.0217081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/05/2019] [Indexed: 11/19/2022] Open
Abstract
Bread wheat (AABBDD) originated from the diploid progenitor Triticum urartu (AA), a relative of Aegilops speltoides (BB), and Ae. tauschii (DD). The DREB1 transcriptional factor plays key regulatory role in low-temperature tolerance. The modern breeding strategies resulted in serious decrease of the agricultural biodiversity, which led to a loss of elite genes underlying abiotic stress tolerance in crops. However, knowledge of this gene's natural diversity is largely unknown in the genome donor species of wheat. We characterized the dehydration response element binding protein 1 (DREB1) gene-diversity pattern in Ae. speltoides, Ae. tauschii, T. monococcum and T. urartu. The highest nucleotide diversity value was detected in Ae. speltoides, followed by Ae. tauschii and T. monococcum. The lowest nucleotide diversity value was observed in T. urartu. Nucleotide diversity and haplotype data might suggest no reduction of nucleotide diversity during T. monococcum domestication. Alignment of the 68 DREB1 sequences found a large-size (70 bp) insertion/deletion in the accession PI486264 of Ae. speltoides, which was different from the copy of sequences from other accessions of Ae. speltoides, suggesting a likely existence of two different ancestral Ae. speltoides forms. Implication of sequences variation of Ae. speltoides on origination of B genome in wheat was discussed.
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Affiliation(s)
- Yi Xu
- College of Agronomy, Anhui Agricultural University, Hefei, Anhui, China
| | - Fang-Yao Sun
- College of Agronomy, Anhui Agricultural University, Hefei, Anhui, China
| | - Chun Ji
- College of Agronomy, Anhui Agricultural University, Hefei, Anhui, China
| | - Quan-Wen Hu
- College of Agronomy, Anhui Agricultural University, Hefei, Anhui, China
| | - Cheng-Yu Wang
- College of Agronomy, Anhui Agricultural University, Hefei, Anhui, China
| | - De-Xiang Wu
- College of Agronomy, Anhui Agricultural University, Hefei, Anhui, China
| | - Genlou Sun
- College of Agronomy, Anhui Agricultural University, Hefei, Anhui, China
- Biology Department, Saint Mary’s University, Halifax, NS, Canada
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15
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Kumar A, Kapoor P, Chunduri V, Sharma S, Garg M. Potential of Aegilops sp. for Improvement of Grain Processing and Nutritional Quality in Wheat ( Triticum aestivum). FRONTIERS IN PLANT SCIENCE 2019; 10:308. [PMID: 30936886 PMCID: PMC6431632 DOI: 10.3389/fpls.2019.00308] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
Wheat is one of the most important staple crops in the world and good source of calories and nutrition. Its flour and dough have unique physical properties and can be processed to make unique products like bread, cakes, biscuits, pasta, noodles etc., which is not possible from other staple crops. Due to domestication, the genetic variability of the genes coding for different economically important traits in wheat is narrow. This genetic variability can be increased by utilizing its wild relatives. Its closest relative, genus Aegilops can be an important source of new alleles. Aegilops has played a very important role in evolution of tetraploid and hexaploid wheat. It consists of 22 species with C, D, M, N, S, T and U genomes with high allelic diversity relative to wheat. Its utilization for wheat improvement for various abiotic and biotic stresses has been reported by various scientific publications. Here in, for the first time, we review the potential of Aegilops for improvement of processing and nutritional traits in wheat. Among processing quality related gluten proteins; high molecular weight glutenins (HMW GS), being easiest to study have been explored in highest number of accessions or lines i.e., 681 belonging to 13 species and selected ones like Ae. searsii, Ae. geniculata and Ae. longissima have been linked with improved bread making quality of wheat. Gliadins and low molecular weight glutenins (LMW GS) have also been extensively explored for wheat improvement and Ae. umbellulata specific LMW GS have been linked with wheat bread making quality improvement. Aegilops has been explored for seed texture diversity and proteins like puroindolins (Pin) and grain softness proteins (GSP). For nutrition quality improvement, it has been screened for essential micronutrients like Fe, Zn, phytochemicals like carotenoids and dietary fibers like arabinoxylan and β-glucan. Ae. kotschyi and Ae. biuncialis transfer in wheat have been associated with higher Fe, Zn content. In this article we have tried to compile information available on exploration of nutritional and processing quality related traits in Aegilops section and their utilization for wheat improvement by different approaches.
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16
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Ruiz M, Bernal G, Giraldo P. An update of low molecular weight glutenin subunits in durum wheat relevant to breeding for quality. J Cereal Sci 2018. [DOI: 10.1016/j.jcs.2018.09.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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17
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Cho K, Beom HR, Jang YR, Altenbach SB, Vensel WH, Simon-Buss A, Lim SH, Kim MG, Lee JY. Proteomic Profiling and Epitope Analysis of the Complex α-, γ-, and ω-Gliadin Families in a Commercial Bread Wheat. FRONTIERS IN PLANT SCIENCE 2018; 9:818. [PMID: 29971078 PMCID: PMC6018075 DOI: 10.3389/fpls.2018.00818] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 05/28/2018] [Indexed: 05/24/2023]
Abstract
Wheat gliadins are a complex group of proteins that contribute to the functional properties of wheat flour doughs and contain epitopes that are relevant for celiac disease (CD) and wheat-dependent exercise-induced anaphylaxis (WDEIA). In this study, we extracted ethanol-soluble gliadin fractions from flour of the Korean bread wheat cultivar Keumkang. Proteins were separated by 2-dimensional gel electrophoresis (2-DE) using a pI range of 6-11 in the first dimension and subjected to tandem mass spectrometry. α-, γ-, and ω-gliadins were identified as the predominant proteins in 31, 28, and one 2-DE spot, respectively. An additional six ω-gliadins were identified in a separate experiment in which a pI range of 3-11 was used for protein separation. We analyzed the composition of CD- and WDEIA-relevant epitopes in the gliadin sequences from Keumkang flour, demonstrating the immunogenic potential of this cultivar. Detailed knowledge about the complement of gliadins accumulated in Keumkang flour provides the background necessary to devise either breeding or biotechnology strategies to improve the functional properties and reduce the adverse health effects of the flour.
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Affiliation(s)
- Kyoungwon Cho
- National Institute of Agricultural Sciences, Rural Development Administration, Jeonju, South Korea
| | - Hye-Rang Beom
- National Institute of Agricultural Sciences, Rural Development Administration, Jeonju, South Korea
| | - You-Ran Jang
- National Institute of Agricultural Sciences, Rural Development Administration, Jeonju, South Korea
| | - Susan B. Altenbach
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, Albany, CA, United States
| | - William H. Vensel
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, Albany, CA, United States
| | - Annamaria Simon-Buss
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, Albany, CA, United States
| | - Sun-Hyung Lim
- National Institute of Agricultural Sciences, Rural Development Administration, Jeonju, South Korea
| | - Min G. Kim
- College of Pharmacy and Research Institute of Pharmaceutical Science, Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, South Korea
| | - Jong-Yeol Lee
- National Institute of Agricultural Sciences, Rural Development Administration, Jeonju, South Korea
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18
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Metakovsky EV, Melnik VA, Redaelli R, Rodriguez-Quijano M. Comparison of Alleles at Gli-2 Loci of Common Wheat by Means of Two-Dimensional Electrophoresis of Gliadin. CYTOL GENET+ 2018. [DOI: 10.3103/s0095452718020068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Metakovsky EV, Melnik VA, Vaccino P, Rodriguez-Quijano M. Comparison of alleles at the Gli-1 loci of common wheat by means of two-dimensional electrophoresis of gliadin and RFLP analysis. CYTOL GENET+ 2018. [DOI: 10.3103/s0095452718010085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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20
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Du X, Tang H, Li M, Ma X, Yin H, Wang H, Zhang X, Qiao X, Li A, Kong L. Molecular characterization of the IgE-binding epitopes in the fast ω-gliadins of Triticeae in relation to wheat-dependent, exercise-induced anaphylaxis. Gene 2016; 591:27-33. [PMID: 27374148 DOI: 10.1016/j.gene.2016.06.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 06/03/2016] [Accepted: 06/20/2016] [Indexed: 01/24/2023]
Abstract
Fast ω-gliadins were minor components of wheat storage proteins but a major antigen triggering allergy to wheat. Sixty-six novel full-length fast ω-gliadin genes with unique characteristics were cloned and sequenced from wheat and its relative species using a PCR-based strategy. Their coding regions ranged from 177bp to 987bp in length and encoded 4.28kDa to 37.56kDa proteins. On the base of first three deduced amino acids at the N-terminal, these genes could be classified into the six subclasses of SRL-, TRQ-, GRL-, NRL-, SRP- and SRM-type ω-gliadin genes. Compared by multiple alignments, these genes were significantly different from each other, due to the insertion or deletion at the repetitive domain. An analysis of the IgE-binding epitopes of the 66 deduced fast ω-gliadins demonstrated that they contained 0-24 IgE-binding epitopes. The phylogenetic tree demonstrated that the fast ω-gliadins and slow ω-gliadins were separated into two groups and their divergence time was 21.64millionyears ago. Sequence data of the fast ω-gliadin genes assist in the study of the origins and evolutions of the different types of ω-gliadins while also providing a basis for the synthesis of monoclonal antibodies to detect wheat antigen content.
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Affiliation(s)
- Xuye Du
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, PR China; College of Food Science, Shandong Agricultural University, No. 61, Daizong Street, Tai'an 271018, Shandong, PR China
| | - Heng Tang
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, PR China
| | - Min Li
- Heze University, No. 2269, Daxue Street, Heze 274015, Shandong, PR China
| | - Xin Ma
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, PR China
| | - Huayan Yin
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, PR China
| | - Hongwei Wang
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, PR China
| | - Xiaocun Zhang
- College of Food Science, Shandong Agricultural University, No. 61, Daizong Street, Tai'an 271018, Shandong, PR China
| | - Xuguang Qiao
- College of Food Science, Shandong Agricultural University, No. 61, Daizong Street, Tai'an 271018, Shandong, PR China
| | - Anfei Li
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, PR China
| | - Lingrang Kong
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, PR China.
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21
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Abstract
Coeliac disease is an intolerance triggered by the ingestion of wheat gluten proteins. It is of increasing concern to consumers and health professionals as its incidence appears to be increasing. The amino acid sequences in gluten proteins that are responsible for triggering responses in sensitive individuals have been identified showing that they vary in distribution among and between different groups of gluten proteins. Conventional breeding may therefore be used to select for gluten protein fractions with lower contents of coeliac epitopes. Molecular breeding approaches can also be used to specifically down-regulate coeliac-toxic proteins or mutate coeliac epitopes within individual proteins. A combination of these approaches may therefore be used to develop a “coeliac-safe” wheat. However, this remains a formidable challenge due to the complex multigenic control of gluten protein composition. Furthermore, any modified wheats must retain acceptable properties for making bread and other processed foods. Not surprisingly, such coeliac-safe wheats have not yet been developed despite over a decade of research. Coeliac disease is of increasing concern as its incidence appears to be increasing. Over 30 amino acid sequences (coeliac epitopes) have been defined. Coeliac epitopes differ in their distribution between wheat gluten proteins. Transgenesis can be used to reduce coeliac-toxic proteins and coeliac epitopes. This can be exploited to develop “coeliac-safe” wheats.
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Affiliation(s)
- Peter R Shewry
- Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK; University of Reading, Whiteknights, Reading, Berkshire RG6 6AH, UK
| | - Arthur S Tatham
- Cardiff School of Heath Sciences, Cardiff Metropolitan University, Llandaff Campus, Western Avenue, Cardiff CF5 2YB, UK
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22
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Zhang Y, Luo G, Liu D, Wang D, Yang W, Sun J, Zhang A, Zhan K. Genome-, Transcriptome- and Proteome-Wide Analyses of the Gliadin Gene Families in Triticum urartu. PLoS One 2015; 10:e0131559. [PMID: 26132381 PMCID: PMC4489009 DOI: 10.1371/journal.pone.0131559] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 06/03/2015] [Indexed: 12/30/2022] Open
Abstract
Gliadins are the major components of storage proteins in wheat grains, and they play an essential role in the dough extensibility and nutritional quality of flour. Because of the large number of the gliadin family members, the high level of sequence identity, and the lack of abundant genomic data for Triticum species, identifying the full complement of gliadin family genes in hexaploid wheat remains challenging. Triticum urartu is a wild diploid wheat species and considered the A-genome donor of polyploid wheat species. The accession PI428198 (G1812) was chosen to determine the complete composition of the gliadin gene families in the wheat A-genome using the available draft genome. Using a PCR-based cloning strategy for genomic DNA and mRNA as well as a bioinformatics analysis of genomic sequence data, 28 gliadin genes were characterized. Of these genes, 23 were α-gliadin genes, three were γ-gliadin genes and two were ω-gliadin genes. An RNA sequencing (RNA-Seq) survey of the dynamic expression patterns of gliadin genes revealed that their synthesis in immature grains began prior to 10 days post-anthesis (DPA), peaked at 15 DPA and gradually decreased at 20 DPA. The accumulation of proteins encoded by 16 of the expressed gliadin genes was further verified and quantified using proteomic methods. The phylogenetic analysis demonstrated that the homologs of these α-gliadin genes were present in tetraploid and hexaploid wheat, which was consistent with T. urartu being the A-genome progenitor species. This study presents a systematic investigation of the gliadin gene families in T. urartu that spans the genome, transcriptome and proteome, and it provides new information to better understand the molecular structure, expression profiles and evolution of the gliadin genes in T. urartu and common wheat.
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Affiliation(s)
- Yanlin Zhang
- College of Agronomy/The Collaborative Innovation Center of Grain Crops in Henan, Henan Agricultural University, Zhengzhou, China
| | - Guangbin Luo
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Dongcheng Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
| | - Dongzhi Wang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Wenlong Yang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
| | - Jiazhu Sun
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
| | - Aimin Zhang
- College of Agronomy/The Collaborative Innovation Center of Grain Crops in Henan, Henan Agricultural University, Zhengzhou, China
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing, China
- * E-mail: (KZ); (AZ)
| | - Kehui Zhan
- College of Agronomy/The Collaborative Innovation Center of Grain Crops in Henan, Henan Agricultural University, Zhengzhou, China
- * E-mail: (KZ); (AZ)
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23
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Srinivasan B, Focke-Tejkl M, Weber M, Pahr S, Baar A, Atreya R, Neurath MF, Vogelsang H, Huber WD, Valenta R. Usefulness of recombinant γ-gliadin 1 for identifying patients with celiac disease and monitoring adherence to a gluten-free diet. J Allergy Clin Immunol 2015; 136:1607-1618.e3. [PMID: 26078104 PMCID: PMC4669310 DOI: 10.1016/j.jaci.2015.04.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 01/18/2023]
Abstract
Background Celiac disease (CD) is an inflammatory disease of the small intestine caused by an immunologic hypersensitivity reaction to dietary wheat gluten. Objectives We sought to clone, express, and perform IgA epitope mapping of a CD-specific wheat antigen and to study its usefulness for identifying patients with CD and monitoring adherence to a gluten-free diet. Methods A synthetic gene coding for γ-gliadin 1 (GG1) was expressed in Escherichia coli. Recombinant γ-gliadin 1 (rGG1) was purified and characterized biochemically, structurally, and immunologically by using sera from patients with CD and control subjects. Overlapping GG1 peptides were synthesized for IgA and IgG epitope mapping. GG1 and peptide-specific antibodies were raised for tracing GG1 in cereals and dietary wheat products and to study its resistance to digestion. Results rGG1 was expressed and purified. rGG1-based IgA ELISAs performed in populations of patients with CD and control subjects showed a specificity of 92.9%, which was higher than that of gliadin extract (e). Furthermore, it allowed monitoring of adherence to a gluten-free diet in patients. A 26-amino-acid peptide from the proline-glutamine–rich repetitive N-terminal region was identified as the immunodominant IgA epitope. GG1-related antigens were found in rye, barley, and spelt but not in oat, rice, or maize. GG1 was detected in dietary wheat products after baking, and in particular, the major IgA epitope–containing region was resistant against digestion. Conclusions rGG1 and its epitope might be useful for identifying patients with CD, monitoring treatment, and studying the pathomechanisms of CD and development of preventive and therapeutic strategies.
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Affiliation(s)
- Bharani Srinivasan
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria
| | - Margarete Focke-Tejkl
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria
| | - Milena Weber
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria
| | - Sandra Pahr
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria
| | - Alexandra Baar
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria
| | - Raja Atreya
- Medical Clinic 1, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Markus F Neurath
- Medical Clinic 1, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Harald Vogelsang
- Department of Gastroenterology and Hepatology, Medical University of Vienna, Vienna, Austria
| | - Wolf-Dietrich Huber
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Rudolf Valenta
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria.
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24
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Novoselskaya-Dragovich AY. Genetics and genomics of wheat: Storage proteins, ecological plasticity, and immunity. RUSS J GENET+ 2015. [DOI: 10.1134/s102279541505004x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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25
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Qi PF, Le CX, Wang Z, Liu YB, Chen Q, Wei ZZ, Xu BJ, Wei ZY, Dai SF, Wei YM, Zheng YL. The γ-gliadin-like γ-prolamin genes in the tribe Triticeae. J Genet 2015; 93:35-41. [PMID: 24840821 DOI: 10.1007/s12041-014-0330-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The γ-prolamins are important components of seed storage proteins in wheat and other Triticeae species. Here, the γ-prolamin genes from the diploid Triticeae species were systemically characterized. Most of the γ-prolamins (except 75 K γ-secalins) characterized were defined as γ-gliadin-like γ-prolamins, since they shared same characteristic model structure with γ-gliadins. Over one-third of these putatively functional γ-prolamin peptides contained different number of cysteine residues as compared to the eight residues present in γ-gliadins. Sequence polymorphism and linkage disequilibrium analyses showed the conservation of γ-prolamin genes in Triticeae species under evolutionary selection. Phylogenetic analyses indicated that these γ-prolamin genes can not be clearly separated according to their genomic origins, reflecting the conservation of γ-gliadinlike γ-prolamin genes after the divergence of Triticeae species. A screening of coeliac disease (CD) toxic epitopes shows that the γ-prolamins from some other genomes contain much fewer epitopes than those from the A, S (B) and D genomes of wheat. These findings contribute to better understanding of γ-prolamin family in Triticeae and build a ground for breeding less CD-toxic wheat cultivars.
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Affiliation(s)
- Peng-Fei Qi
- Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan 611130, People's Republic of China.
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26
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Przysiecka Ł, Książkiewicz M, Wolko B, Naganowska B. Structure, expression profile and phylogenetic inference of chalcone isomerase-like genes from the narrow-leafed lupin (Lupinus angustifolius L.) genome. FRONTIERS IN PLANT SCIENCE 2015; 6:268. [PMID: 25954293 PMCID: PMC4404975 DOI: 10.3389/fpls.2015.00268] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 04/03/2015] [Indexed: 05/20/2023]
Abstract
Lupins, like other legumes, have a unique biosynthesis scheme of 5-deoxy-type flavonoids and isoflavonoids. A key enzyme in this pathway is chalcone isomerase (CHI), a member of CHI-fold protein family, encompassing subfamilies of CHI1, CHI2, CHI-like (CHIL), and fatty acid-binding (FAP) proteins. Here, two Lupinus angustifolius (narrow-leafed lupin) CHILs, LangCHIL1 and LangCHIL2, were identified and characterized using DNA fingerprinting, cytogenetic and linkage mapping, sequencing and expression profiling. Clones carrying CHIL sequences were assembled into two contigs. Full gene sequences were obtained from these contigs, and mapped in two L. angustifolius linkage groups by gene-specific markers. Bacterial artificial chromosome fluorescence in situ hybridization approach confirmed the localization of two LangCHIL genes in distinct chromosomes. The expression profiles of both LangCHIL isoforms were very similar. The highest level of transcription was in the roots of the third week of plant growth; thereafter, expression declined. The expression of both LangCHIL genes in leaves and stems was similar and low. Comparative mapping to reference legume genome sequences revealed strong syntenic links; however, LangCHIL2 contig had a much more conserved structure than LangCHIL1. LangCHIL2 is assumed to be an ancestor gene, whereas LangCHIL1 probably appeared as a result of duplication. As both copies are transcriptionally active, questions arise concerning their hypothetical functional divergence. Screening of the narrow-leafed lupin genome and transcriptome with CHI-fold protein sequences, followed by Bayesian inference of phylogeny and cross-genera synteny survey, identified representatives of all but one (CHI1) main subfamilies. They are as follows: two copies of CHI2, FAPa2 and CHIL, and single copies of FAPb and FAPa1. Duplicated genes are remnants of whole genome duplication which is assumed to have occurred after the divergence of Lupinus, Arachis, and Glycine.
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Affiliation(s)
- Łucja Przysiecka
- Department of Genomics, Institute of Plant Genetics of the Polish Academy of SciencesPoznań, Poland
- NanoBioMedical Centre, Adam Mickiewicz UniversityPoznań, Poland
| | - Michał Książkiewicz
- Department of Genomics, Institute of Plant Genetics of the Polish Academy of SciencesPoznań, Poland
- *Correspondence: Michał Książkiewicz, Department of Genomics, Institute of Plant Genetics of the Polish Academy of Sciences, Strzeszyńska 34, Poznań 60-479, Poland
| | - Bogdan Wolko
- Department of Genomics, Institute of Plant Genetics of the Polish Academy of SciencesPoznań, Poland
| | - Barbara Naganowska
- Department of Genomics, Institute of Plant Genetics of the Polish Academy of SciencesPoznań, Poland
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Rasheed A, Xia X, Yan Y, Appels R, Mahmood T, He Z. Wheat seed storage proteins: Advances in molecular genetics, diversity and breeding applications. J Cereal Sci 2014. [DOI: 10.1016/j.jcs.2014.01.020] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Brooks SC, Fischer RL, Huh JH, Eichman BF. 5-methylcytosine recognition by Arabidopsis thaliana DNA glycosylases DEMETER and DML3. Biochemistry 2014; 53:2525-32. [PMID: 24678721 PMCID: PMC4004242 DOI: 10.1021/bi5002294] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Methylation of cytosine to 5-methylcytosine
(5mC) is important
for gene expression, gene imprinting, X-chromosome inactivation, and
transposon silencing. Active demethylation in animals is believed
to proceed by DNA glycosylase removal of deaminated or oxidized 5mC.
In plants, 5mC is removed from the genome directly by the DEMETER
(DME) family of DNA glycosylases. Arabidopsis thaliana DME excises 5mC to activate expression of maternally imprinted genes.
Although the related Repressor of Silencing 1 (ROS1) enzyme has been
characterized, the molecular basis for 5mC recognition by DME has
not been investigated. Here, we present a structure–function
analysis of DME and the related DME-like 3 (DML3) glycosylases for
5mC and its oxidized derivatives. Relative to 5mC, DME and DML3 exhibited
robust activity toward 5-hydroxymethylcytosine, limited activity for
5-carboxylcytosine, and no activity for 5-formylcytosine. We used
homology modeling and mutational analysis of base excision and DNA
binding to identify residues important for recognition of 5mC within
the context of DNA and inside the enzyme active site. Our results
indicate that the 5mC binding pocket is composed of residues from
discrete domains and is responsible for discrimination against 5mC
derivatives, and suggest that DME, ROS1, and DML3 utilize subtly different
mechanisms to probe the DNA duplex for cytosine modifications.
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Affiliation(s)
- Sonja C Brooks
- Department of Biological Sciences and Center for Structural Biology, Vanderbilt University , Nashville, Tennessee 37232, United States
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Zhang W, Ciclitira P, Messing J. PacBio sequencing of gene families - a case study with wheat gluten genes. Gene 2013; 533:541-6. [PMID: 24144842 DOI: 10.1016/j.gene.2013.10.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 10/03/2013] [Indexed: 12/16/2022]
Abstract
Amino acids in wheat (Triticum aestivum) seeds mainly accumulate in storage proteins called gliadins and glutenins. Gliadins contain α/β-, γ- and ω-types whereas glutenins contain HMW- and LMW-types. Known gliadin and glutenin sequences were largely determined through cloning and sequencing by capillary electrophoresis. This time-consuming process prevents us to intensively study the variation of each orthologous gene copy among cultivars. The throughput and sequencing length of Pacific Bioscience RS (PacBio) single molecule sequencing platform make it feasible to construct contiguous and non-chimeric RNA sequences. We assembled 424 wheat storage protein transcripts from ten wheat cultivars by using just one single-molecule-real-time cell. The protein genes from wheat cultivar Chinese Spring are comparable to known sequences from NCBI. We demonstrated real-time sequencing of gene families with high-throughput and low-cost. This method can be applied to studies of gene amplification and copy number variation among species and cultivars.
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Affiliation(s)
- Wei Zhang
- Waksman Institute of Microbiology, Rutgers University, 190 Frelinghuysen Road, Piscataway, NJ 08854, USA
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31
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Qi PF, Chen Q, Ouellet T, Wang Z, Le CX, Wei YM, Lan XJ, Zheng YL. The molecular diversity of α-gliadin genes in the tribe Triticeae. Genetica 2013; 141:303-10. [PMID: 23892918 DOI: 10.1007/s10709-013-9729-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 07/18/2013] [Indexed: 01/28/2023]
Abstract
Many of the unique properties of wheat flour are derived from seed storage proteins such as the α-gliadins. In this study these α-gliadin genes from diploid Triticeae species were systemically characterized, and divided into 3 classes according to the distinct organization of their protein domains. Our analyses indicated that these α-gliadins varied in the number of cysteine residues they contained. Most of the α-gliadin genes were grouped according to their genomic origins within the phylogenetic tree. As expected, sequence alignments suggested that the repetitive domain and the two polyglutamine regions were responsible for length variations of α-gliadins as were the insertion/deletion of structural domains within the three different classes (I, II, and III) of α-gliadins. A screening of celiac disease toxic epitopes indicated that the α-gliadins of the class II, derived from the Ns genome, contain no epitope, and that some other genomes contain much fewer epitopes than the A, S(B) and D genomes of wheat. Our results suggest that the observed genetic differences in α-gliadins of Triticeae might indicate their use as a fertile ground for the breeding of less CD-toxic wheat varieties.
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Affiliation(s)
- Peng-Fei Qi
- Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, China
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32
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A combined biochemical, biophysical and immunological approach towards the identification of celiac disease-specific wheat antigens. Amino Acids 2013; 45:889-900. [PMID: 23836418 DOI: 10.1007/s00726-013-1537-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 06/17/2013] [Indexed: 02/07/2023]
Abstract
Celiac disease (CD) is an inflammatory affliction of the small bowel caused by an immunological hypersensitivity to ingested wheat antigens affecting almost 1 % of the population. The gliadin fraction of wheat has been shown to contain the pathogenic antigens which react with antibodies and T cells. However, there is only limited knowledge regarding the precise nature of the wheat antigens recognized by IgA antibodies from CD patients and diagnostic tests based on the gliadin fraction have been demonstrated to give frequently false positive results. The aim of this study was the characterization of wheat antigens specifically recognized by IgA antibodies of CD patients. We developed a combined biochemical, biophysical, and immunological approach for the identification of celiac disease-specific wheat antigens. It is based on sub-fractionation of the wheat gliadin fraction using two ion exchange chromatography steps, the localization of CD-specific antigens by immunoblotting with IgA antibodies from CD patients, subsequent digestion followed by electro spray ionization-liquid chromatography/mass spectrometry (LC-ESI-MS/MS) and N-terminal sequencing by Edman degradation. Through the sub-fractionation procedure it was possible to separate CD-specific IgA-reactive wheat antigens from other wheat antigens which were also recognized by IgA antibodies of individuals without CD or by CD patients on gluten-free diet. Analysis by LC-ESI-MS/MS and N-terminal sequencing of the sub-fractions and the proteins specifically recognized by CD patients identified certain γ-gliadins with molecular mass of 37,000 and 45,000 as CD-specific wheat antigens. The CD-specific γ-gliadins with the molecular mass of 37,000 and 45,000 should be useful to study pathomechanisms of the disease and to improve the specificity of diagnostic tests for CD.
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Crooijmans RPMA, Fife MS, Fitzgerald TW, Strickland S, Cheng HH, Kaiser P, Redon R, Groenen MAM. Large scale variation in DNA copy number in chicken breeds. BMC Genomics 2013; 14:398. [PMID: 23763846 PMCID: PMC3751642 DOI: 10.1186/1471-2164-14-398] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 06/04/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Detecting genetic variation is a critical step in elucidating the molecular mechanisms underlying phenotypic diversity. Until recently, such detection has mostly focused on single nucleotide polymorphisms (SNPs) because of the ease in screening complete genomes. Another type of variant, copy number variation (CNV), is emerging as a significant contributor to phenotypic variation in many species. Here we describe a genome-wide CNV study using array comparative genomic hybridization (aCGH) in a wide variety of chicken breeds. RESULTS We identified 3,154 CNVs, grouped into 1,556 CNV regions (CNVRs). Thirty percent of the CNVs were detected in at least 2 individuals. The average size of the CNVs detected was 46.3 kb with the largest CNV, located on GGAZ, being 4.3 Mb. Approximately 75% of the CNVs are copy number losses relatively to the Red Jungle Fowl reference genome. The genome coverage of CNVRs in this study is 60 Mb, which represents almost 5.4% of the chicken genome. In particular large gene families such as the keratin gene family and the MHC show extensive CNV. CONCLUSIONS A relative large group of the CNVs are line-specific, several of which were previously shown to be related to the causative mutation for a number of phenotypic variants. The chance that inter-specific CNVs fall into CNVRs detected in chicken is related to the evolutionary distance between the species. Our results provide a valuable resource for the study of genetic and phenotypic variation in this phenotypically diverse species.
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Affiliation(s)
- Richard P M A Crooijmans
- Animal Breeding and Genomics Centre, Wageningen University, P.O. Box 338, Wageningen 6700 AH, The Netherlands.
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34
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Anderson OD, Huo N, Gu YQ. The gene space in wheat: the complete γ-gliadin gene family from the wheat cultivar Chinese Spring. Funct Integr Genomics 2013; 13:261-73. [PMID: 23564033 DOI: 10.1007/s10142-013-0321-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/14/2013] [Accepted: 03/19/2013] [Indexed: 12/20/2022]
Abstract
The complete set of unique γ-gliadin genes is described for the wheat cultivar Chinese Spring using a combination of expressed sequence tag (EST) and Roche 454 DNA sequences. Assemblies of Chinese Spring ESTs yielded 11 different γ-gliadin gene sequences. Two of the sequences encode identical polypeptides and are assumed to be the result of a recent gene duplication. One gene has a 3' coding mutation that changes the reading frame in the final eight codons. A second assembly of Chinese Spring γ-gliadin sequences was generated using Roche 454 total genomic DNA sequences. The 454 assembly confirmed the same 11 active genes as the EST assembly plus two pseudogenes not represented by ESTs. These 13 γ-gliadin sequences represent the complete unique set of γ-gliadin genes for cv Chinese Spring, although not ruled out are additional genes that are exact duplications of these 13 genes. A comparison with the ESTs of two other hexaploid cultivars (Butte 86 and Recital) finds that the most active genes are present in all three cultivars, with exceptions likely due to too few ESTs for detection in Butte 86 and Recital. A comparison of the numbers of ESTs per gene indicates differential levels of expression within the γ-gliadin gene family. Genome assignments were made for 6 of the 13 Chinese Spring γ-gliadin genes, i.e., one assignment from a match to two γ-gliadin genes found within a tetraploid wheat A genome BAC and four genes that match four distinct γ-gliadin sequences assembled from Roche 454 sequences from Aegilops tauschii, the hexaploid wheat D-genome ancestor.
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Affiliation(s)
- Olin D Anderson
- Genomics and Gene Discovery Research Unit, Western Regional Research Unit, Agricultural Research Service, US Department of Agriculture, 800 Buchanan Street, Albany, CA 94710, USA.
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Li GR, Liu C, Yang EN, Yang ZJ. Isolation and phylogenetic analysis of novel γ-gliadin genes in genus Dasypyrum. GENETICS AND MOLECULAR RESEARCH 2013; 12:783-90. [PMID: 23546962 DOI: 10.4238/2013.march.13.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
As the most ancient member of the wheat gluten family, the γ-gliadin genes are suitable for phylogenetic analysis among wheat and related species. Species in the grass genus Dasypyrum have been widely used for wheat cross breeding. However, the genomic relationships among Dasypyrum species have been little studied. We isolated 22 novel γ-gliadin gene sequences, among which 10 are putatively functional. The open reading frame lengths of these sequences range from 642 to 933 bp, and these putative proteins consist of five domains. Phylogenetic analyses showed that all Dasypyrum γ-gliadin gene sequences clustered in a large group; D. villosum and tetraploid D. breviaristatum γ-gliadin gene sequences clustered in a subgroup, while diploid D. breviaristatum γ-gliadin gene sequences clustered at the edge of the subgroup. All of the Dasypyrum γ-gliadin gene sequences were absent in three major T cell-stimulatory epitopes binding to HLA-DQ2/8 in celiac disease patients. Based on the phylogenetic analyses, we suggest that D. villosum and tetraploid D. breviaristatum evolved in parallel from a diploid ancestor D. breviaristatum.
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Affiliation(s)
- G R Li
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
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36
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Wan Y, Shewry PR, Hawkesford MJ. A novel family of γ-gliadin genes are highly regulated by nitrogen supply in developing wheat grain. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:161-8. [PMID: 23162123 PMCID: PMC3528027 DOI: 10.1093/jxb/ers318] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Six wheat cultivars were grown at Rothamsted (UK) with three levels of nitrogen fertilizer (100, 200 and 350 kg N/ha) in 2009 and 2010. Gene expression in developing caryopses at 21 days post-anthesis (DPA) was profiled using the Affymetrix Wheat GeneChip. Four of 105 transcripts which were significantly upregulated by nitrogen level were annotated as γ-3 hordein and the identification of corresponding expressed sequence tags showed that they differed in sequence from previously described (typical) γ-gliadins and represented a novel form of γ-gliadin. Real-time reverse transcriptase PCR at 14, 21, 28 and 35 DPA revealed that this transcript was most abundant and most responsive to nitrogen at 21 DPA. Four novel γ-gliadin genes were isolated by PCR amplification from wheat cv. Hereward and the related species Aegilops tauschii and Triticum monococcum while three were assembled from the genomic sequence database of wheat cv. Chinese Spring (www.cerealsdb.uk.net). Comparison of the deduced amino acid sequences of the seven genes showed that they shared only 44.4-46.0% identity with the sequence of a typical γ-gliadin (accession number EF15018), but 61.8-68.3% identity with the sequence of γ-3 hordein from the wild barley species Hordeum chilense (AY338065). The novel γ-gliadin genes were localized to the group 1 chromosomes (1A, 1B, 1D).
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Rombouts I, Lagrain B, Brunnbauer M, Delcour JA, Koehler P. Improved identification of wheat gluten proteins through alkylation of cysteine residues and peptide-based mass spectrometry. Sci Rep 2013; 3:2279. [PMID: 23880742 PMCID: PMC3721084 DOI: 10.1038/srep02279] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 07/09/2013] [Indexed: 11/22/2022] Open
Abstract
The concentration and composition of wheat gluten proteins and the presence, concentration and location of cysteine residues therein are important for wheat flour quality. However, it is difficult to identify gluten proteins, as they are an extremely polymorphic mixture of prolamins. We here present methods for cysteine labeling of wheat prolamins with 4-vinylpyridine (4-VP) and iodoacetamide (IDAM) which, as compared to label-free analysis, substantially improve identification of cysteine-containing peptides in enzymic prolamin digests by electrospray ionization--tandem mass spectrometry. Both chymotrypsin and thermolysin yielded cysteine-containing peptides from different gluten proteins, but more proteins could be identified after chymotryptic digestion. In addition, to the best of our knowledge, we were the first to label prolamins with isotope coded affinity tags (ICAT), which are commonly used for quantitative proteomics. However, more peptides were detected after labeling gluten proteins with 4-VP and IDAM than with ICAT.
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Affiliation(s)
- Ine Rombouts
- German Research Center for Food Chemistry, Leibniz Institute, Lise-Meitner-Strasse 34, D-85354 Freising, Germany.
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Structural genes of wheat and barley 5-methylcytosine DNA glycosylases and their potential applications for human health. Proc Natl Acad Sci U S A 2012. [PMID: 23184965 DOI: 10.1073/pnas.1217927109] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Wheat supplies about 20% of the total food calories consumed worldwide and is a national staple in many countries. Besides being a key source of plant proteins, it is also a major cause of many diet-induced health issues, especially celiac disease. The only effective treatment for this disease is a total gluten-free diet. The present report describes an effort to develop a natural dietary therapy for this disorder by transcriptional suppression of wheat DEMETER (DME) homeologs using RNA interference. DME encodes a 5-methylcytosine DNA glycosylase responsible for transcriptional derepression of gliadins and low-molecular-weight glutenins (LMWgs) by active demethylation of their promoters in the wheat endosperm. Previous research has demonstrated these proteins to be the major source of immunogenic epitopes. In this research, barley and wheat DME genes were cloned and localized on the syntenous chromosomes. Nucleotide diversity among DME homeologs was studied and used for their virtual transcript profiling. Functional conservation of DME enzyme was confirmed by comparing the motif and domain structure within and across the plant kingdom. Presence and absence of CpG islands in prolamin gene sequences was studied as a hallmark of hypo- and hypermethylation, respectively. Finally the epigenetic influence of DME silencing on accumulation of LMWgs and gliadins was studied using 20 transformants expressing hairpin RNA in their endosperm. These transformants showed up to 85.6% suppression in DME transcript abundance and up to 76.4% reduction in the amount of immunogenic prolamins, demonstrating the possibility of developing wheat varieties compatible for the celiac patients.
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Goryunova SV, Salentijn EMJ, Chikida NN, Kochieva EZ, van der Meer IM, Gilissen LJWJ, Smulders MJM. Expansion of the gamma-gliadin gene family in Aegilops and Triticum. BMC Evol Biol 2012; 12:215. [PMID: 23137212 PMCID: PMC3537741 DOI: 10.1186/1471-2148-12-215] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Accepted: 10/31/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The gamma-gliadins are considered to be the oldest of the gliadin family of storage proteins in Aegilops/Triticum. However, the expansion of this multigene family has not been studied in an evolutionary perspective. RESULTS We have cloned 59 gamma-gliadin genes from Aegilops and Triticum species (Aegilops caudata L., Aegilops comosa Sm. in Sibth. & Sm., Aegilops mutica Boiss., Aegilops speltoides Tausch, Aegilops tauschii Coss., Aegilops umbellulata Zhuk., Aegilops uniaristata Vis., and Triticum monococcum L.) representing eight different genomes: Am, B/S, C, D, M, N, T and U. Overall, 15% of the sequences contained internal stop codons resulting in pseudogenes, but this percentage was variable among genomes, up to over 50% in Ae. umbellulata. The most common length of the deduced protein, including the signal peptide, was 302 amino acids, but the length varied from 215 to 362 amino acids, both obtained from Ae. speltoides. Most genes encoded proteins with eight cysteines. However, all Aegilops species had genes that encoded a gamma-gliadin protein of 302 amino acids with an additional cysteine. These conserved nine-cysteine gamma-gliadins may perform a specific function, possibly as chain terminators in gluten network formation in protein bodies during endosperm development. A phylogenetic analysis of gamma-gliadins derived from Aegilops and Triticum species and the related genera Lophopyrum, Crithopsis, and Dasypyrum showed six groups of genes. Most Aegilops species contained gamma-gliadin genes from several of these groups, which also included sequences from the genera Lophopyrum, Crithopsis, and Dasypyrum. Hordein and secalin sequences formed separate groups. CONCLUSIONS We present a model for the evolution of the gamma-gliadins from which we deduce that the most recent common ancestor (MRCA) of Aegilops/Triticum-Dasypyrum-Lophopyrum-Crithopsis already had four groups of gamma-gliadin sequences, presumably the result of two rounds of duplication of the locus.
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Affiliation(s)
- Svetlana V Goryunova
- Wageningen UR Plant Breeding, Wageningen UR, P,O, Box 16, Wageningen, NL-6700 AA, The Netherlands
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Wang S, Shen X, Ge P, Li J, Subburaj S, Li X, Zeller FJ, Hsam SLK, Yan Y. Molecular characterization and dynamic expression patterns of two types of γ-gliadin genes from Aegilops and Triticum species. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2012; 125:1371-84. [PMID: 22751951 DOI: 10.1007/s00122-012-1917-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 06/06/2012] [Indexed: 05/25/2023]
Abstract
Gliadins were the major components of wheat storage proteins and determine the extensibility properties of gluten dough. In this work, 19 new full-length γ-gliadin genes were isolated from various Aegilops and Triticum species. Sequence characterization showed that a specific octapeptide and celiac disease (CD)-toxic epitope Gliγ-3 (VQGQGIIQPQQPAQL) were present in the rich glutamine domain and C-terminal non-repetitive domain, respectively. Based on the sequence features of both peptides, a new classification system for γ-gliadin gene family was established, in which γ-gliadins were classified into two types (types I and II) with each consisting of two groups. An uneven distribution of different types and groups of γ-gliadin genes was exhibited among 11 Aegilops and Triticum genomes. Phylogenetic analysis revealed that types I and II genes diverged at about 14 MYA while the divergence of 4 γ-gliadin group genes occurred at around 10 MYA almost simultaneously. The γ-gliadin genes from S(l) and B genomes displayed a different transcriptional expression pattern during grain development, and rapid increasing of gliadin mRNA and proteins occurred at 15-20 DPA. In addition, genome-specific variations of CD-toxic epitopes among Aegilops and Triticum genomes were found. The A genome and its related progenitor genomes A(u) and A(m) had fewer CD epitopes than other genomes, suggesting that these genomes might be valuable gene resources to remove CD toxic peptides for wheat quality improvement.
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Affiliation(s)
- Shunli Wang
- Key Laboratory of Genetics and Biotechnology, College of Life Science, Capital Normal University, Beijing, 100048, China
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41
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Salentijn EMJ, Mitea DC, Goryunova SV, van der Meer IM, Padioleau I, Gilissen LJWJ, Koning F, Smulders MJM. Celiac disease T-cell epitopes from gamma-gliadins: immunoreactivity depends on the genome of origin, transcript frequency, and flanking protein variation. BMC Genomics 2012; 13:277. [PMID: 22726570 PMCID: PMC3469346 DOI: 10.1186/1471-2164-13-277] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 05/02/2012] [Indexed: 02/04/2023] Open
Abstract
Background Celiac disease (CD) is caused by an uncontrolled immune response to gluten, a heterogeneous mixture of wheat storage proteins. The CD-toxicity of these proteins and their derived peptides is depending on the presence of specific T-cell epitopes (9-mer peptides; CD epitopes) that mediate the stimulation of HLA-DQ2/8 restricted T-cells. Next to the thoroughly characterized major T-cell epitopes derived from the α-gliadin fraction of gluten, γ-gliadin peptides are also known to stimulate T-cells of celiac disease patients. To pinpoint CD-toxic γ-gliadins in hexaploid bread wheat, we examined the variation of T-cell epitopes involved in CD in γ-gliadin transcripts of developing bread wheat grains. Results A detailed analysis of the genetic variation present in γ-gliadin transcripts of bread wheat (T. aestivum, allo-hexaploid, carrying the A, B and D genome), together with genomic γ-gliadin sequences from ancestrally related diploid wheat species, enabled the assignment of sequence variants to one of the three genomic γ-gliadin loci, Gli-A1, Gli-B1 or Gli-D1. Almost half of the γ-gliadin transcripts of bread wheat (49%) was assigned to locus Gli-D1. Transcripts from each locus differed in CD epitope content and composition. The Gli-D1 transcripts contained the highest frequency of canonical CD epitope cores (on average 10.1 per transcript) followed by the Gli-A1 transcripts (8.6) and the Gli-B1 transcripts (5.4). The natural variants of the major CD epitope from γ-gliadins, DQ2-γ-I, showed variation in their capacity to induce in vitro proliferation of a DQ2-γ-I specific and HLA-DQ2 restricted T-cell clone. Conclusions Evaluating the CD epitopes derived from γ-gliadins in their natural context of flanking protein variation, genome specificity and transcript frequency is a significant step towards accurate quantification of the CD toxicity of bread wheat. This approach can be used to predict relative levels of CD toxicity of individual wheat cultivars directly from their transcripts (cDNAs).
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Affiliation(s)
- Elma M J Salentijn
- Plant Research International, Wageningen UR, P.O. Box 16, NL-6700 AA, Wageningen, The Netherlands.
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Qi PF, Wei YM, Chen Q, Ouellet T, Ai J, Chen GY, Li W, Zheng YL. Identification of novel α-gliadin genes. Genome 2011; 54:244-52. [PMID: 21423287 DOI: 10.1139/g10-114] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ten novel α-gliadin genes (Gli-ta, Gli-turg1, Gli-turg2, Gli-turg3, Gli-turg4, Gli-turg5, Gli-turg6, Gli-cs1, Gli-cs2, and Gli-cs3) with unique characteristics were isolated from wheat (Triticum aestivumL.), among which Gli-cs1, Gli-cs2, Gli-cs3, and Gli-turg6 were pseudogenes. Gli-cs3 and nine other sequences were much larger and smaller, respectively, than the typical α-gliadins. This variation was caused by insertion or deletion of the unique domain I and a polyglutamine region, possibly the result of illegitimate recombination. Consequently, Gli-cs3 contained 10 cysteine residues, whereas there were 2 cysteine residues only in the other nine sequences. Gli-ta/Gli-ta-like α-gliadin genes are normally expressed during the development of seeds. SDS-PAGE analysis showed that in-vitro-expressed Gli-ta could form intermolecular disulphide bonds and could be chain extenders. A protein band similar in size to Gli-ta has been observed in seed extracts, and mass spectrometry results confirm that the band contains small molecular mass α-gliadins, which is a characteristic of the novel α-gliadins. Mass spectrometry results also indicated that the two cysteine residues of Gli-ta/Gli-ta-like proteins participated in the formation of intermolecular disulphide bonds in vivo.
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Affiliation(s)
- Peng-Fei Qi
- Triticeae Research Institute, Sichuan Agricultural University, Yaan, Sichuan, China
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Seed proteomics. J Proteomics 2011; 74:389-400. [DOI: 10.1016/j.jprot.2010.12.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 12/08/2010] [Accepted: 12/10/2010] [Indexed: 12/29/2022]
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Characterization of ω-secalin genes from rye, triticale, and a wheat 1BL/1RS translocation line. J Appl Genet 2011; 51:403-11. [PMID: 21063058 DOI: 10.1007/bf03208870] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Sixty-two DNA sequences for the coding regions of omega-secalin (ω-secalin) genes have been characterized from rye (Secale cereale L.), hexaploid and octoploid triticale (× Triticosecale Wittmack), and wheat (Triticum aestivum L.) 1BL/1RS translocation line. Only 19 out of the 62 ω-secalin gene sequences were full-length open reading frames (ORFs), which can be expressed into functional proteins. The other 43 DNA sequences were pseudogenes, as their ORFs were interrupted by one or a few stop codons or frameshift mutations. The 19 ω-secalin genes have a typical primary structure, which is different from wheat gliadins. There was no cysteine residue in ω-secalin proteins, and the potential celiac disease (CD) toxic epitope (PQQP) was identified to appear frequently in the repetitive domains. The ω-secalin genes from various cereal species shared high homology in their gene sequences. The ω-secalin gene family has involved fewer variations after the integration of the rye R chromosome or whole genome into the wheat or triticale genome. The higher Ka/Ks ratio (i.e. non-synonymous to synonymous substitutions per site) in ω-secalin pseudogenes than in ω-secalin ORFs indicate that the pseudogenes may be subject to a reduced selection pressure. Based on the conserved sequences of ω-secalin genes, it will be possible to manipulate the expression of this gene family in rye, triticale, or wheat 1BL/1RS translocation lines, to reduce its negative effects on grain quality.
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Dupont FM, Vensel WH, Tanaka CK, Hurkman WJ, Altenbach SB. Deciphering the complexities of the wheat flour proteome using quantitative two-dimensional electrophoresis, three proteases and tandem mass spectrometry. Proteome Sci 2011; 9:10. [PMID: 21314956 PMCID: PMC3238214 DOI: 10.1186/1477-5956-9-10] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 02/11/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Wheat flour is one of the world's major food ingredients, in part because of the unique end-use qualities conferred by the abundant glutamine- and proline-rich gluten proteins. Many wheat flour proteins also present dietary problems for consumers with celiac disease or wheat allergies. Despite the importance of these proteins it has been particularly challenging to use MS/MS to distinguish the many proteins in a flour sample and relate them to gene sequences. RESULTS Grain from the extensively characterized spring wheat cultivar Triticum aestivum 'Butte 86' was milled to white flour from which proteins were extracted, then separated and quantified by 2-DE. Protein spots were identified by separate digestions with three proteases, followed by tandem mass spectrometry analysis of the peptides. The spectra were used to interrogate an improved protein sequence database and results were integrated using the Scaffold program. Inclusion of cultivar specific sequences in the database greatly improved the results, and 233 spots were identified, accounting for 93.1% of normalized spot volume. Identified proteins were assigned to 157 wheat sequences, many for proteins unique to wheat and nearly 40% from Butte 86. Alpha-gliadins accounted for 20.4% of flour protein, low molecular weight glutenin subunits 18.0%, high molecular weight glutenin subunits 17.1%, gamma-gliadins 12.2%, omega-gliadins 10.5%, amylase/protease inhibitors 4.1%, triticins 1.6%, serpins 1.6%, purinins 0.9%, farinins 0.8%, beta-amylase 0.5%, globulins 0.4%, other enzymes and factors 1.9%, and all other 3%. CONCLUSIONS This is the first successful effort to identify the majority of abundant flour proteins for a single wheat cultivar, relate them to individual gene sequences and estimate their relative levels. Many genes for wheat flour proteins are not expressed, so this study represents further progress in describing the expressed wheat genome. Use of cultivar-specific contigs helped to overcome the difficulties of matching peptides to gene sequences for members of highly similar, rapidly evolving storage protein families. Prospects for simplifying this process for routine analyses are discussed. The ability to measure expression levels for individual flour protein genes complements information gained from efforts to sequence the wheat genome and is essential for studies of effects of environment on gene expression.
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Affiliation(s)
- Frances M Dupont
- USDA Agricultural Research Service, Western Regional Research Center, Albany CA 94710, USA
| | - William H Vensel
- USDA Agricultural Research Service, Western Regional Research Center, Albany CA 94710, USA
| | - Charlene K Tanaka
- USDA Agricultural Research Service, Western Regional Research Center, Albany CA 94710, USA
| | - William J Hurkman
- USDA Agricultural Research Service, Western Regional Research Center, Albany CA 94710, USA
| | - Susan B Altenbach
- USDA Agricultural Research Service, Western Regional Research Center, Albany CA 94710, USA
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Guo ZF, Zhong M, Wei YM, Zhang L, Ma H, Li HG, Chen LJ, Lin JW, Zhang LJ, Zheng YL. Characterization of two novel γ-gliadin genes encoded by K genome of Crithopsis delileana and evolution analysis with those from Triticeae. Genes Genomics 2010. [DOI: 10.1007/s13258-010-0005-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Altenbach SB, Vensel WH, DuPont FM. Analysis of expressed sequence tags from a single wheat cultivar facilitates interpretation of tandem mass spectrometry data and discrimination of gamma gliadin proteins that may play different functional roles in flour. BMC PLANT BIOLOGY 2010; 10:7. [PMID: 20064259 PMCID: PMC2827424 DOI: 10.1186/1471-2229-10-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2009] [Accepted: 01/11/2010] [Indexed: 05/22/2023]
Abstract
BACKGROUND The gamma gliadins are a complex group of proteins that together with other gluten proteins determine the functional properties of wheat flour. The proteins have unusually high levels of glutamine and proline and contain large regions of repetitive sequences. While most gamma gliadins are monomeric proteins containing eight conserved cysteine residues, some contain an additional cysteine residue that enables them to be linked with other gluten proteins into large polymers that are critical for flour quality. The ability to differentiate among the gamma gliadins is important for studies of wheat flour quality because proteins with similar sequences can have different effects on functional properties. RESULTS The complement of gamma gliadin genes expressed in the wheat cultivar Butte 86 was evaluated by analyzing publicly available expressed sequence tag (EST) data. Eleven contigs were assembled from 153 Butte 86 ESTs. Nine of the contigs encoded full-length proteins and four of the proteins contained nine cysteine residues. Only one of the encoded proteins was a perfect match with a sequence reported in NCBI. Contigs from four different publicly available EST assemblies encoded proteins that were perfect matches with some, but not all, of the Butte 86 gamma gliadins and the complement of identical proteins was different for each assembly. A specialized database that included the sequences of Butte 86 gamma gliadins was constructed for identification of flour proteins by tandem mass spectrometry (MS/MS). In a pilot experiment, proteins corresponding to six Butte 86 gamma gliadin contigs were distinguished by MS/MS, including one containing the extra cysteine residue. Two other proteins were identified as one of two closely related Butte 86 proteins but could not be distinguished unequivocally. Unique peptide tags specific for Butte 86 gamma gliadins are reported. CONCLUSIONS Inclusion of cultivar-specific gamma gliadin sequences in databases maximizes the number and quality of peptide identifications and increases sequence coverage of these gamma gliadins by MS/MS. This approach makes it possible to distinguish closely related proteins, to associate individual proteins with sequences of specific genes, and to evaluate proteomic data in a biological context to better address questions about wheat flour quality.
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Affiliation(s)
- Susan B Altenbach
- USDA-ARS Western Regional Research Center, 800 Buchanan Street, Albany, CA 94710 USA
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