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Portilla Llerena JP, Kiyota E, dos Santos FRC, Garcia JC, de Lima RF, Mayer JLS, dos Santos Brito M, Mazzafera P, Creste S, Nobile PM. ShF5H1 overexpression increases syringyl lignin and improves saccharification in sugarcane leaves. GM CROPS & FOOD 2024; 15:67-84. [PMID: 38507337 PMCID: PMC10956634 DOI: 10.1080/21645698.2024.2325181] [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: 10/21/2023] [Accepted: 02/26/2024] [Indexed: 03/22/2024]
Abstract
The agricultural sugarcane residues, bagasse and straws, can be used for second-generation ethanol (2GE) production by the cellulose conversion into glucose (saccharification). However, the lignin content negatively impacts the saccharification process. This polymer is mainly composed of guaiacyl (G), hydroxyphenyl (H), and syringyl (S) units, the latter formed in the ferulate 5-hydroxylase (F5H) branch of the lignin biosynthesis pathway. We have generated transgenic lines overexpressing ShF5H1 under the control of the C4H (cinnamate 4-hydroxylase) rice promoter, which led to a significant increase of up to 160% in the S/G ratio and 63% in the saccharification efficiency in leaves. Nevertheless, the content of lignin was unchanged in this organ. In culms, neither the S/G ratio nor sucrose accumulation was altered, suggesting that ShF5H1 overexpression would not affect first-generation ethanol production. Interestingly, the bagasse showed a significantly higher fiber content. Our results indicate that the tissue-specific manipulation of the biosynthetic branch leading to S unit formation is industrially advantageous and has established a foundation for further studies aiming at refining lignin modifications. Thus, the ShF5H1 overexpression in sugarcane emerges as an efficient strategy to improve 2GE production from straw.
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Affiliation(s)
- Juan Pablo Portilla Llerena
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
- Academic Department of Biology, Professional and Academic School of Biology, Universidad Nacional de San Agustín de Arequipa, Arequipa, Perú
| | - Eduardo Kiyota
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
| | | | - Julio C. Garcia
- Centro de Cana, Instituto Agronômico (IAC), Ribeirão Preto, Brazil
| | | | | | - Michael dos Santos Brito
- Centro de Cana, Instituto Agronômico (IAC), Ribeirão Preto, Brazil
- Institute of Science and Technology, Federal University of São Paulo, São José dos Campos, Brazil
| | - Paulo Mazzafera
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
| | - Silvana Creste
- Centro de Cana, Instituto Agronômico (IAC), Ribeirão Preto, Brazil
- Departamento de Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Lam LPY, Lui ACW, Bartley LE, Mikami B, Umezawa T, Lo C. Multifunctional 5-hydroxyconiferaldehyde O-methyltransferases (CAldOMTs) in plant metabolism. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1671-1695. [PMID: 38198655 DOI: 10.1093/jxb/erae011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 01/09/2024] [Indexed: 01/12/2024]
Abstract
Lignin, flavonoids, melatonin, and stilbenes are plant specialized metabolites with diverse physiological and biological functions, supporting plant growth and conferring stress resistance. Their biosynthesis requires O-methylations catalyzed by 5-hydroxyconiferaldehyde O-methyltransferase (CAldOMT; also called caffeic acid O-methyltransferase, COMT). CAldOMT was first known for its roles in syringyl (S) lignin biosynthesis in angiosperm cell walls and later found to be multifunctional. This enzyme also catalyzes O-methylations in flavonoid, melatonin, and stilbene biosynthetic pathways. Phylogenetic analysis indicated the convergent evolution of enzymes with OMT activities towards the monolignol biosynthetic pathway intermediates in some gymnosperm species that lack S-lignin and Selaginella moellendorffii, a lycophyte which produces S-lignin. Furthermore, neofunctionalization of CAldOMTs occurred repeatedly during evolution, generating unique O-methyltransferases (OMTs) with novel catalytic activities and/or accepting novel substrates, including lignans, 1,2,3-trihydroxybenzene, and phenylpropenes. This review summarizes multiple aspects of CAldOMTs and their related proteins in plant metabolism and discusses their evolution, molecular mechanism, and roles in biorefineries, agriculture, and synthetic biology.
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Affiliation(s)
- Lydia Pui Ying Lam
- Graduate School of Engineering Science, Akita University, Tegata Gakuen-machi 1-1, Akita City, Akita 010-0852, Japan
| | - Andy C W Lui
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA
| | - Laura E Bartley
- Institute of Biological Chemistry, Washington State University, Pullman, WA 99164, USA
| | - Bunzo Mikami
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Toshiaki Umezawa
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Clive Lo
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
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Laksana C, Sophiphun O, Chanprame S. Lignin reduction in sugarcane by performing CRISPR/Cas9 site-direct mutation of SoLIM transcription factor. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2024; 340:111987. [PMID: 38220093 DOI: 10.1016/j.plantsci.2024.111987] [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: 09/11/2023] [Revised: 01/08/2024] [Accepted: 01/10/2024] [Indexed: 01/16/2024]
Abstract
Genetic engineering of plant cell walls is limited for reducing lignocellulose recalcitrance, so mild and/or green-like pretreatment is still required for sequential enzymatic saccharification. Here, we report a method to reduce lignin content in sugarcane stalks using the CRISPR/Cas 9 technique. Three target sequences of SoLIM were designed and fused to pRGEB32. The cassette constructs were introduced into sugarcane calli cv. KK3 through Agrobacterium-mediated transformation. We produced one base substitution and one insertion line for the 1st target site; two insertions, one deletion, and one base substitution for the 2nd target site; and one base substitution and insertion for the 3rd target site. qRT-PCR analysis of SoLIM, SoPAL, SoC4H, and SoCAD showeded that downregulation of SoLIM by single nucleotide insertions or deletions reduced the expression of SoPAL, SoC4H, and SoCAD. Consequently, the edited lines contained 9.74 to 51.46% less lignin content compared to that in the wild-type plants. The syringyl/guaiacyl (S/G) ratio of the edited lines ranged between 0.23 and 0.49, while the wild-type was 0.22. The histochemical evaluation and scanning electron microscopy of the cell walls supported this observation. A low lignin content sugarcane will provide a better feedstock for second-generation bioethanol production.
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Affiliation(s)
- Chanakan Laksana
- Faculty of Agricultural Technology, Burapha University Sakaeo Campus, Sakaeo 27160, Thailand
| | - Onsulang Sophiphun
- Faculty of Agricultural Technology, Burapha University Sakaeo Campus, Sakaeo 27160, Thailand
| | - Sontichai Chanprame
- Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Nakhon Pathom 73140, Thailand.
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Sharma S, Malhotra PK, Goyal M, Sharma V, Mittal A, Yadav IS, Sanghera GS, Chhuneja P. Characterization of sugarcane mutants developed through gamma irradiations for their lignin content and caffeic acid-O-methyl transferase ( COMT) gene mutations. Int J Radiat Biol 2024; 100:619-626. [PMID: 38166242 DOI: 10.1080/09553002.2023.2295962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 12/05/2023] [Indexed: 01/04/2024]
Abstract
PURPOSE Bagasse, the residue left after extracting juice from sugarcane stalks, is rich in lignocellulosic biomass. The lignin present in this plant biomass is the key factor that hinders the efficient extraction of ethanol from the bagasse. In the current study, γ-irradiated sugarcane mutants were evaluated for variation in lignin content and its corresponding caffeic acid-O-methyl transferase (COMT) gene. MATERIALS AND METHODS The acetyl bromide method was used to estimate lignin content in sugarcane mutants. PCR-based cloning of the COMT gene was performed in low lignin mutants as well as control plants in E. coli (strain DH5α) to understand the mechanism of variation at the molecular level. The Sanger sequencing for cloned gene was performed to check variation in gene sequence. RESULTS In comparison to the control (21.5%), the mutant plants' lignin content ranged from 13 to 28%. The Sanger sequencing revealed approximately the same length of the gene from mutants as well as a control plant. In comparison to the reference gene, the mutated gene showed SNPs and indels in different regions, which may have an impact on lignin content. CONCLUSIONS Therefore, γ-irradiated mutagenesis is an acceptable approach to develop novel mutants of sugarcane with low lignin content to enhance bioethanol production from waste material using bioprocess technology.
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Affiliation(s)
- Shaweta Sharma
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, India
| | - Pawan Kumar Malhotra
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, India
| | - Meenakshi Goyal
- Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, India
| | - Vishal Sharma
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, India
- Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Solan, India
| | - Amandeep Mittal
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, India
| | - Inderjit Singh Yadav
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, India
| | | | - Parveen Chhuneja
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, India
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Podder A, Ahmed FF, Suman MZH, Mim AY, Hasan K. Genome-wide identification of DCL, AGO and RDR gene families and their associated functional regulatory element analyses in sunflower (Helianthus annuus). PLoS One 2023; 18:e0286994. [PMID: 37294803 PMCID: PMC10256174 DOI: 10.1371/journal.pone.0286994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 05/27/2023] [Indexed: 06/11/2023] Open
Abstract
RNA interference (RNAi) regulates a variety of eukaryotic gene expressions that are engaged in response to stress, growth, and the conservation of genomic stability during developmental phases. It is also intimately connected to the post-transcriptional gene silencing (PTGS) process and chromatin modification levels. The entire process of RNA interference (RNAi) pathway gene families mediates RNA silencing. The main factors of RNA silencing are the Dicer-Like (DCL), Argonaute (AGO), and RNA-dependent RNA polymerase (RDR) gene families. To the best of our knowledge, genome-wide identification of RNAi gene families like DCL, AGO, and RDR in sunflower (Helianthus annuus) has not yet been studied despite being discovered in some species. So, the goal of this study is to find the RNAi gene families like DCL, AGO, and RDR in sunflower based on bioinformatics approaches. Therefore, we accomplished an inclusive in silico investigation for genome-wide identification of RNAi pathway gene families DCL, AGO, and RDR through bioinformatics approaches such as (sequence homogeneity, phylogenetic relationship, gene structure, chromosomal localization, PPIs, GO, sub-cellular localization). In this study, we have identified five DCL (HaDCLs), fifteen AGO (HaAGOs), and ten RDR (HaRDRs) in the sunflower genome database corresponding to the RNAi genes of model plant Arabidopsis thaliana based on genome-wide analysis and a phylogenetic method. The analysis of the gene structure that contains exon-intron numbers, conserved domain, and motif composition analyses for all HaDCL, HaAGO, and HaRDR gene families indicated almost homogeneity among the same gene family. The protein-protein interaction (PPI) network analysis illustrated that there exists interconnection among identified three gene families. The analysis of the Gene Ontology (GO) enrichment showed that the detected genes directly contribute to the RNA gene-silencing and were involved in crucial pathways. It was observed that the cis-acting regulatory components connected to the identified genes were shown to be responsive to hormone, light, stress, and other functions. That was found in HaDCL, HaAGO, and HaRDR genes associated with the development and growth of plants. Finally, we are able to provide some essential information about the components of sunflower RNA silencing through our genome-wide comparison and integrated bioinformatics analysis, which open the door for further research into the functional mechanisms of the identified genes and their regulatory elements.
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Affiliation(s)
- Anamika Podder
- Department of Mathematics, Faculty of Science, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Fee Faysal Ahmed
- Department of Mathematics, Faculty of Science, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Md. Zahid Hasan Suman
- Department of Mathematics, Faculty of Science, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Afsana Yeasmin Mim
- Department of Mathematics, Faculty of Science, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Khadiza Hasan
- Department of Mathematics, Faculty of Science, Jashore University of Science and Technology, Jashore, Bangladesh
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Assem SK, Basry MA, Taha TA, El-Aziz MHA, Alwa T, Fouad WM. Development of an in vitro regeneration system from immature inflorescences and CRISPR/Cas9-mediated gene editing in sudangrass. J Genet Eng Biotechnol 2023; 21:58. [PMID: 37184575 DOI: 10.1186/s43141-023-00517-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 05/06/2023] [Indexed: 05/16/2023]
Abstract
BACKGROUND Sudangrass (Sorghum sudanense) is a major biomass producer for livestock feed and biofuel in many countries. It has a wide range of adaptations for growing on marginal lands under biotic and abiotic stresses. The immature inflorescence is an explant with high embryogenic competence and is frequently used to regenerate different sorghum cultivars. Caffeic acid O-methyl transferase (COMT) is a key enzyme in the lignin biosynthesis pathway, which limits ruminant digestion of forage cell walls and is a crucial barrier in the conversion of plant biomass to bioethanol. Genome editing by CRISPR/Cas9-mediated mutagenesis without a transgenic footprint will accelerate the improvement and facilitate regulatory approval and commercialization of biotech crops. METHODS AND RESULTS We report the overcome of the recalcitrance in sudangrass transformation and regeneration in order to use genome editing technique. Hence, an efficient regeneration system has been established to induce somatic embryogenesis from the immature inflorescence of two sudangrass cultivars on four MS-based media supplemented with different components. Our results indicate an interaction between genotype and medium composition. The combination of Giza-1 cultivar and M4 medium produces the maximum frequency of embryogenic calli of 80% and subsequent regeneration efficiency of 22.6%. Precise mutagenesis of the COMT gene is executed using the CRISPR/Cas9 system with the potential to reduce lignin content and enhance forage and biomass quality in sudangrass. CONCLUSION A reliable regeneration and transformation system has been established for sudangrass using immature inflorescence, and the CRISPR/Cas9 system has demonstrated a promising technology for genome editing. The outcomes of this research will pave the road for further improvement of various sorghum genotypes to meet the global demand for food, feed, and biofuels, achieving sustainable development goals (SDGs).
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Affiliation(s)
- Shireen K Assem
- Department of Plant Molecular Biology, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center (ARC), Giza, Egypt.
| | - Mahmoud A Basry
- Department of Plant Molecular Biology, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center (ARC), Giza, Egypt
| | - Taha A Taha
- Department of Plant Molecular Biology, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center (ARC), Giza, Egypt
| | - M H Abd El-Aziz
- Genetics Department, Faculty of Agriculture, Mansoura University, Mansoura, Egypt
| | - Taher Alwa
- Department of Plant Molecular Biology, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center (ARC), Giza, Egypt
| | - Walid M Fouad
- Department of Biology, School of Science and Engineering, American University in Cairo, New Cairo, 11835, Cairo, Egypt
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Ravikiran KT, Thribhuvan R, Sheoran S, Kumar S, Kushwaha AK, Vineeth TV, Saini M. Tailoring crops with superior product quality through genome editing: an update. PLANTA 2023; 257:86. [PMID: 36949234 DOI: 10.1007/s00425-023-04112-4] [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: 09/06/2022] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
In this review, using genome editing, the quality trait alterations in important crops have been discussed, along with the challenges encountered to maintain the crop products' quality. The delivery of economic produce with superior quality is as important as high yield since it dictates consumer's acceptance and end use. Improving product quality of various agricultural and horticultural crops is one of the important targets of plant breeders across the globe. Significant achievements have been made in various crops using conventional plant breeding approaches, albeit, at a slower rate. To keep pace with ever-changing consumer tastes and preferences and industry demands, such efforts must be supplemented with biotechnological tools. Fortunately, many of the quality attributes are resultant of well-understood biochemical pathways with characterized genes encoding enzymes at each step. Targeted mutagenesis and transgene transfer have been instrumental in bringing out desired qualitative changes in crops but have suffered from various pitfalls. Genome editing, a technique for methodical and site-specific modification of genes, has revolutionized trait manipulation. With the evolution of versatile and cost effective CRISPR/Cas9 system, genome editing has gained significant traction and is being applied in several crops. The availability of whole genome sequences with the advent of next generation sequencing (NGS) technologies further enhanced the precision of these techniques. CRISPR/Cas9 system has also been utilized for desirable modifications in quality attributes of various crops such as rice, wheat, maize, barley, potato, tomato, etc. The present review summarizes salient findings and achievements of application of genome editing for improving product quality in various crops coupled with pointers for future research endeavors.
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Affiliation(s)
- K T Ravikiran
- ICAR-Central Soil Salinity Research Institute, Regional Research Station, Lucknow, Uttar Pradesh, India
| | - R Thribhuvan
- ICAR-Central Research Institute for Jute and Allied Fibres, Barrackpore, West Bengal, India
| | - Seema Sheoran
- ICAR-Indian Agricultural Research Institute, Regional Station, Karnal, Haryana, India.
| | - Sandeep Kumar
- ICAR-Indian Institute of Natural Resins and Gums, Ranchi, Jharkhand, India
| | - Amar Kant Kushwaha
- ICAR-Central Institute for Subtropical Horticulture, Lucknow, Uttar Pradesh, India
| | - T V Vineeth
- ICAR-Central Soil Salinity Research Institute, Regional Research Station, Bharuch, Gujarat, India
- Department of Plant Physiology, College of Agriculture, Kerala Agricultural University, Vellanikkara, Thrissur, Kerala, India
| | - Manisha Saini
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
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Martin AF, Tobimatsu Y, Lam PY, Matsumoto N, Tanaka T, Suzuki S, Kusumi R, Miyamoto T, Takeda-Kimura Y, Yamamura M, Koshiba T, Osakabe K, Osakabe Y, Sakamoto M, Umezawa T. Lignocellulose molecular assembly and deconstruction properties of lignin-altered rice mutants. PLANT PHYSIOLOGY 2023; 191:70-86. [PMID: 36124989 PMCID: PMC9806629 DOI: 10.1093/plphys/kiac432] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
Bioengineering approaches to modify lignin content and structure in plant cell walls have shown promise for facilitating biochemical conversions of lignocellulosic biomass into valuable chemicals. Despite numerous research efforts, however, the effect of altered lignin chemistry on the supramolecular assembly of lignocellulose and consequently its deconstruction in lignin-modified transgenic and mutant plants is not fully understood. In this study, we aimed to close this gap by analyzing lignin-modified rice (Oryza sativa L.) mutants deficient in 5-HYDROXYCONIFERALDEHYDE O-METHYLTRANSFERASE (CAldOMT) and CINNAMYL ALCOHOL DEHYDROGENASE (CAD). A set of rice mutants harboring knockout mutations in either or both OsCAldOMT1 and OsCAD2 was generated in part by genome editing and subjected to comparative cell wall chemical and supramolecular structure analyses. In line with the proposed functions of CAldOMT and CAD in grass lignin biosynthesis, OsCAldOMT1-deficient mutant lines produced altered lignins depleted of syringyl and tricin units and incorporating noncanonical 5-hydroxyguaiacyl units, whereas OsCAD2-deficient mutant lines produced lignins incorporating noncanonical hydroxycinnamaldehyde-derived units. All tested OsCAldOMT1- and OsCAD2-deficient mutants, especially OsCAldOMT1-deficient lines, displayed enhanced cell wall saccharification efficiency. Solid-state nuclear magnetic resonance (NMR) and X-ray diffraction analyses of rice cell walls revealed that both OsCAldOMT1- and OsCAD2 deficiencies contributed to the disruptions of the cellulose crystalline network. Further, OsCAldOMT1 deficiency contributed to the increase of the cellulose molecular mobility more prominently than OsCAD2 deficiency, resulting in apparently more loosened lignocellulose molecular assembly. Such alterations in cell wall chemical and supramolecular structures may in part account for the variations of saccharification performance of the OsCAldOMT1- and OsCAD2-deficient rice mutants.
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Affiliation(s)
- Andri Fadillah Martin
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Research Center for Genetic Engineering, National Research and Innovation Agency (BRIN), Bogor, 16911, Indonesia
| | - Yuki Tobimatsu
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Pui Ying Lam
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Center for Crossover Education, Graduate School of Engineering Science, Akita University, Akita, 010-8502, Japan
| | - Naoyuki Matsumoto
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Takuto Tanaka
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Shiro Suzuki
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Faculty of Applied Biological Sciences, Gifu University, Gifu, 501-1193, Japan
| | - Ryosuke Kusumi
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Takuji Miyamoto
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Sakeology Center, Niigata University, Niigata, 950-2181, Japan
| | - Yuri Takeda-Kimura
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin, 53706, USA
| | - Masaomi Yamamura
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, 770-8503, Japan
| | - Taichi Koshiba
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- National Agriculture and Food Research Organization, Tsukuba, 305-8517, Japan
| | - Keishi Osakabe
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, 770-8503, Japan
| | - Yuriko Osakabe
- School of Life Science and Technology, Tokyo Institute of Technology, Tokyo, 152-8550, Japan
| | - Masahiro Sakamoto
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Toshiaki Umezawa
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Research Unit for Realization of Sustainable Society (RURSS), Kyoto University, Uji, 611-0011, Japan
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Bharathi JK, Anandan R, Benjamin LK, Muneer S, Prakash MAS. Recent trends and advances of RNA interference (RNAi) to improve agricultural crops and enhance their resilience to biotic and abiotic stresses. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 194:600-618. [PMID: 36529010 DOI: 10.1016/j.plaphy.2022.11.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 11/04/2022] [Accepted: 11/26/2022] [Indexed: 06/17/2023]
Abstract
Over the last two decades, significant advances have been made using genetic engineering technology to modify genes from various exotic origins and introduce them into plants to induce favorable traits. RNA interference (RNAi) was discovered earlier as a natural process for controlling the expression of genes across all higher species. It aims to enhance precision and accuracy in pest/pathogen resistance, quality improvement, and manipulating the architecture of plants. However, it existed as a widely used technique recently. RNAi technologies could well be used to down-regulate any genes' expression without disrupting the expression of other genes. The use of RNA interference to silence genes in various organisms has become the preferred method for studying gene functions. The establishment of new approaches and applications for enhancing desirable characters is essential in crops by gene suppression and the refinement of knowledge of endogenous RNAi mechanisms in plants. RNAi technology in recent years has become an important and choicest method for controlling insects, pests, pathogens, and abiotic stresses like drought, salinity, and temperature. Although there are certain drawbacks in efficiency of this technology such as gene candidate selection, stability of trigger molecule, choice of target species and crops. Nevertheless, from past decade several target genes has been identified in numerous crops for their improvement towards biotic and abiotic stresses. The current review is aimed to emphasize the research done on crops under biotic and abiotic stress using RNAi technology. The review also highlights the gene regulatory pathways/gene silencing, RNA interference, RNAi knockdown, RNAi induced biotic and abiotic resistance and advancements in the understanding of RNAi technology and the functionality of various components of the RNAi machinery in crops for their improvement.
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Affiliation(s)
- Jothi Kanmani Bharathi
- Department of Genetics and Plant Breeding, Faculty of Agriculture, Annamalai University, Annamalai Nagar, 608 002, Tamil Nadu, India
| | - Ramaswamy Anandan
- Department of Genetics and Plant Breeding, Faculty of Agriculture, Annamalai University, Annamalai Nagar, 608 002, Tamil Nadu, India
| | - Lincy Kirubhadharsini Benjamin
- Horticulture and Molecular Physiology Lab, School of Agricultural Innovations and Advanced Learning, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | - Sowbiya Muneer
- Horticulture and Molecular Physiology Lab, School of Agricultural Innovations and Advanced Learning, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India.
| | - Muthu Arjuna Samy Prakash
- Department of Genetics and Plant Breeding, Faculty of Agriculture, Annamalai University, Annamalai Nagar, 608 002, Tamil Nadu, India.
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Duran Garzon C, Lequart M, Charras Q, Fournet F, Bellenger L, Sellier-Richard H, Giauffret C, Vermerris W, Domon JM, Rayon C. The maize low-lignin brown midrib3 mutant shows pleiotropic effects on photosynthetic and cell wall metabolisms in response to chilling. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 184:75-86. [PMID: 35636334 DOI: 10.1016/j.plaphy.2022.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 02/03/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Maize (Zea mays L.) is one of the major cereal crops in the world and is highly sensitive to low temperature. Here, changes in photosynthetic and cell wall metabolisms were investigated during a long chilling exposure in inbred line F2 and a low-lignin near-isogenic brown midrib3 mutant (F2bm3), which has a mutation in the caffeic acid O-methyltransferase (COMT) gene. Results revealed that the plant biomass was reduced, and this was more pronounced in F2bm3. Photosynthesis was altered in both lines with distinct changes in photosynthetic pigment content between F2bm3 and F2, indicating an alternative photoprotection mechanism between lines under chilling. Starch remobilization was observed in F2bm3 while concentrations of sucrose, fructose and starch increased in F2, suggesting a reduced sugar partitioning in F2. The cell wall was altered upon chilling, resulting in changes in the composition of glucuronorabinoxylan and a reduced cellulose level in F2. Chilling shifted lignin subunit composition in F2bm3 mutant to a higher proportion of p-hydroxyphenyl (H) units, whereas it resulted in lignin with a higher proportion of syringyl (S) residues in F2. On average, the total cell wall ferulic acid (FA) content increased in both genotypes, with an increase in ether-linked FA in F2bm3, suggesting a greater degree of cross-linking to lignin. The reinforcement of the cell wall with lignin enriched in H-units and a higher concentration in cell-wall-bound FA observed in F2bm3 as a response to chilling, could be a strategy to protect the photosystems.
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Affiliation(s)
- Catalina Duran Garzon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Michelle Lequart
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Quentin Charras
- UMR 7265 Aix Marseille Université, CEA, CNRS, BIAM, Laboratoire de Génétique et Biophysique des Plantes, 13108, Saint Paul-Lez-Durance, France
| | - Françoise Fournet
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Léo Bellenger
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France; EA2106 Biomolécules et Biotechnologies Végétales, Faculté de Pharmacie, Université de Tours, Parc de Grandmont, 37200, Tours, France
| | - Hélène Sellier-Richard
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, Unité Expérimentale Grandes Cultures Innovation et Environnement, Estrées-Mons, 80203, Péronne, France
| | - Catherine Giauffret
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, AgroImpact, Estrées-Mons, 80203, Péronne, France
| | - Wilfred Vermerris
- Department of Microbiology & Cell Science, UF Genetics Institute, Florida Center for Renewable Chemicals and Fuels, University of Florida, Gainesville, FL, 32610, USA
| | - Jean-Marc Domon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France
| | - Catherine Rayon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039, Amiens, France.
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11
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Kouhen M, García-Caparrós P, Twyman RM, Abdelly C, Mahmoudi H, Schillberg S, Debez A. Improving environmental stress resilience in crops by genome editing: insights from extremophile plants. Crit Rev Biotechnol 2022; 43:559-574. [PMID: 35606905 DOI: 10.1080/07388551.2022.2042481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In basic and applied sciences, genome editing has become an indispensable tool, especially the versatile and adaptable CRISPR/Cas9 system. Using CRISPR/Cas9 in plants has enabled modifications of many valuable traits, including environmental stress tolerance, an essential aspect when it comes to ensuring food security under climate change pressure. The CRISPR toolbox enables faster and more precise plant breeding by facilitating: multiplex gene editing, gene pyramiding, and de novo domestication. In this paper, we discuss the most recent advances in CRISPR/Cas9 and alternative CRISPR-based systems, along with the technical challenges that remain to be overcome. A revision of the latest proof-of-concept and functional characterization studies has indeed provided more insight into the quantitative traits affecting crop yield and stress tolerance. Additionally, we focus on the applications of CRISPR/Cas9 technology in regard to extremophile plants, due to their significance on: industrial, ecological and economic levels. These still unexplored genetic resources could provide the means to harden our crops against the threat of climate change, thus ensuring food security over the next century.
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Affiliation(s)
- Mohamed Kouhen
- Centre of Biotechnology of Borj-Cedria (CBBC), Laboratory of Extremophile Plants (LPE), Hammam-Lif, Tunisia.,Department of Biosciences and Territory, University of Molise, Pesche, Italy
| | - Pedro García-Caparrós
- Agronomy Department of Superior School Engineering, University of Almeria, CIAIMBITAL, Almería, Spain
| | | | - Chedly Abdelly
- Centre of Biotechnology of Borj-Cedria (CBBC), Laboratory of Extremophile Plants (LPE), Hammam-Lif, Tunisia
| | - Henda Mahmoudi
- International Center for Biosaline Agriculture, Academic City, Near Zayed University, Dubai, United Arab Emirates
| | - Stefan Schillberg
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Ahmed Debez
- Centre of Biotechnology of Borj-Cedria (CBBC), Laboratory of Extremophile Plants (LPE), Hammam-Lif, Tunisia
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Mohan C, Easterling M, Yau YY. Gene Editing Technologies for Sugarcane Improvement: Opportunities and Limitations. SUGAR TECH : AN INTERNATIONAL JOURNAL OF SUGAR CROPS & RELATED INDUSTRIES 2022; 24:369-385. [PMID: 34667393 PMCID: PMC8517945 DOI: 10.1007/s12355-021-01045-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 08/07/2021] [Indexed: 05/05/2023]
Abstract
Plant-based biofuels present a promising alternative to depleting non-renewable fuel resources. One of the benefits of biofuel is reduced environmental impact, including reduction in greenhouse gas emission which causes climate change. Sugarcane is one of the most important bioenergy crops. Sugarcane juice is used to produce table sugar and first-generation biofuel (e.g., bioethanol). Sugarcane bagasse is also a potential material for second-generation cellulosic biofuel production. Researchers worldwide are striving to improve sugarcane biomass yield and quality by a variety of means including biotechnological tools. This paper reviews the use of sugarcane as a feedstock for biofuel production, and gene manipulation tools and approaches, including RNAi and genome-editing tools, such as TALENs and CRISPR-Cas9, for improving its quality. The specific focus here is on CRISPR system because it is low cost, simple in design and versatile compared to other genome-editing tools. The advance of CRISPR-Cas9 technology has transformed plant research with its ability to precisely delete, insert or replace genes in recent years. Lignin is the primary material responsible for biomass recalcitrance in biofuel production. The use of genome editing technology to modify lignin composition and distribution in sugarcane cell wall has been realized. The current and potential applications of genome editing technology for sugarcane improvement are discussed. The advantages and limitations of utilizing RNAi and TALEN techniques in sugarcane improvement are discussed as well.
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Affiliation(s)
- Chakravarthi Mohan
- Department of Genetics and Evolution, Federal University of São Carlos, São Carlos, Brazil
| | - Mona Easterling
- Department of Natural Sciences, Northeastern State University, Broken Arrow, OK 74014 USA
- Northeast Campus, Tulsa Community College, 3727 East Apache St, Tulsa, OK 74115 USA
| | - Yuan-Yeu Yau
- Department of Natural Sciences, Northeastern State University, Broken Arrow, OK 74014 USA
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Ahmed FF, Hossen MI, Sarkar MAR, Konak JN, Zohra FT, Shoyeb M, Mondal S. Genome-wide identification of DCL, AGO and RDR gene families and their associated functional regulatory elements analyses in banana (Musa acuminata). PLoS One 2021; 16:e0256873. [PMID: 34473743 PMCID: PMC8412350 DOI: 10.1371/journal.pone.0256873] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 08/17/2021] [Indexed: 12/15/2022] Open
Abstract
RNA silencing is mediated through RNA interference (RNAi) pathway gene families, i.e., Dicer-Like (DCL), Argonaute (AGO), and RNA-dependent RNA polymerase (RDR) and their cis-acting regulatory elements. The RNAi pathway is also directly connected with the post-transcriptional gene silencing (PTGS) mechanism, and the pathway controls eukaryotic gene regulation during growth, development, and stress response. Nevertheless, genome-wide identification of RNAi pathway gene families such as DCL, AGO, and RDR and their regulatory network analyses related to transcription factors have not been studied in many fruit crop species, including banana (Musa acuminata). In this study, we studied in silico genome-wide identification and characterization of DCL, AGO, and RDR genes in bananas thoroughly via integrated bioinformatics approaches. A genome-wide analysis identified 3 MaDCL, 13 MaAGO, and 5 MaRDR candidate genes based on multiple sequence alignment and phylogenetic tree related to the RNAi pathway in banana genomes. These genes correspond to the Arabidopsis thaliana RNAi silencing genes. The analysis of the conserved domain, motif, and gene structure (exon-intron numbers) for MaDCL, MaAGO, and MaRDR genes showed higher homogeneity within the same gene family. The Gene Ontology (GO) enrichment analysis exhibited that the identified RNAi genes could be involved in RNA silencing and associated metabolic pathways. A number of important transcription factors (TFs), e.g., ERF, Dof, C2H2, TCP, GATA and MIKC_MADS families, were identified by network and sub-network analyses between TFs and candidate RNAi gene families. Furthermore, the cis-acting regulatory elements related to light-responsive (LR), stress-responsive (SR), hormone-responsive (HR), and other activities (OT) functions were identified in candidate MaDCL, MaAGO, and MaRDR genes. These genome-wide analyses of these RNAi gene families provide valuable information related to RNA silencing, which would shed light on further characterization of RNAi genes, their regulatory elements, and functional roles, which might be helpful for banana improvement in the breeding program.
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Affiliation(s)
- Fee Faysal Ahmed
- Faculty of Science, Department of Mathematics, Jashore University of Science and Technology, Jashore, Bangladesh
- * E-mail:
| | - Md. Imran Hossen
- Faculty of Science, Department of Mathematics, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Md. Abdur Rauf Sarkar
- Faculty of Biological Science and Technology, Department of Genetic Engineering and Biotechnology, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Jesmin Naher Konak
- Faculty of Life Science, Department of Biochemistry and Molecular Biology, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Fatema Tuz Zohra
- Faculty of Agriculture, Laboratory of Fruit Science, Saga University, Honjo-machi, Saga, Japan
| | - Md. Shoyeb
- Faculty of Biological Science and Technology, Department of Genetic Engineering and Biotechnology, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Samiran Mondal
- Faculty of Science, Department of Mathematics, Jashore University of Science and Technology, Jashore, Bangladesh
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Qamar Z, Nasir IA, Abouhaidar MG, Hefferon KL, Rao AQ, Latif A, Ali Q, Anwar S, Rashid B, Shahid AA. Novel approaches to circumvent the devastating effects of pests on sugarcane. Sci Rep 2021; 11:12428. [PMID: 34127751 PMCID: PMC8203629 DOI: 10.1038/s41598-021-91985-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 05/21/2021] [Indexed: 02/05/2023] Open
Abstract
Sugarcane (Saccharum officinarum L.) is a cash crop grown commercially for its higher amounts of sucrose, stored within the mature internodes of the stem. Numerous studies have been done for the resistance development against biotic and abiotic stresses to save the sucrose yields. Quality and yield of sugarcane production is always threatened by the damages of cane borers and weeds. In current study two problems were better addressed through the genetic modification of sugarcane for provision of resistance against insects and weedicide via the expression of two modified cane borer resistant CEMB-Cry1Ac (1.8 kb), CEMB-Cry2A (1.9 kb) and one glyphosate tolerant CEMB-GTGene (1.4 kb) genes, driven by maize Ubiquitin Promoter and nos terminator. Insect Bio-toxicity assays were carried out for the assessment of Cry proteins through mortality percent of shoot borer Chilo infuscatellus at 2nd instar larvae stage. During V0, V1 and V2 generations young leaves from the transgenic sugarcane plants were collected at plant age of 20, 40, 60, 80 days and fed to the Chilo infuscatellus larvae. Up to 100% mortality of Chilo infuscatellus from 80 days old transgenic plants of V2 generation indicated that these transgenic plants were highly resistant against shoot borer and the gene expression level is sufficient to provide complete resistance against target pests. Glyphosate spray assay was carried out for complete removal of weeds. In V1-generation, 70-76% transgenic sugarcane plants were found tolerant against glyphosate spray (3000 mL/ha) under field conditions. While in V2-generation, the replicates of five selected lines 4L/2, 5L/5, 6L/5, L8/4, and L9/6 were found 100% tolerant against 3000 mL/ha glyphosate spray. It is evident from current study that CEMB-GTGene, CEMB-Cry1Ac and CEMB-Cry2A genes expression in sugarcane variety CPF-246 showed an efficient resistance against cane borers (Chilo infuscatellus) and was also highly tolerant against glyphosate spray. The selected transgenic sugarcane lines showed sustainable resistance against cane borer and glyphosate spray can be further exploited at farmer's field level after fulfilling the biosafety requirements to boost the sugarcane production in the country.
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Affiliation(s)
- Zahida Qamar
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan.
| | - Idrees Ahmad Nasir
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Mounir G Abouhaidar
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | | | - Abdul Qayyum Rao
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Ayesha Latif
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Qurban Ali
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
| | - Saima Anwar
- Pakistan Biomedical Engineering Centre University of Engineering and Technology, New Campus, Lahore, Pakistan
| | - Bushra Rashid
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Ahmad Ali Shahid
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
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15
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Li X, Ma F, Liang C, Wang M, Zhang Y, Shen Y, Adnan M, Lu P, Khan MT, Huang J, Zhang M. Precise high-throughput online near-infrared spectroscopy assay to determine key cell wall features associated with sugarcane bagasse digestibility. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:123. [PMID: 34051834 PMCID: PMC8164326 DOI: 10.1186/s13068-021-01979-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 05/21/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Sugarcane is one of the most crucial energy crops that produces high yields of sugar and lignocellulose. The cellulose crystallinity index (CrI) and lignin are the two kinds of key cell wall features that account for lignocellulose saccharification. Therefore, high-throughput screening of sugarcane germplasm with excellent cell wall features is considered a promising strategy to enhance bagasse digestibility. Recently, there has been research to explore near-infrared spectroscopy (NIRS) assays for the characterization of the corresponding wall features. However, due to the technical barriers of the offline strategy, it is difficult to apply for high-throughput real-time analyses. This study was therefore initiated to develop a high-throughput online NIRS assay to rapidly detect cellulose crystallinity, lignin content, and their related proportions in sugarcane, aiming to provide an efficient and feasible method for sugarcane cell wall feature evaluation. RESULTS A total of 838 different sugarcane genotypes were collected at different growth stages during 2018 and 2019. A continuous variation distribution of the near-infrared spectrum was observed among these collections. Due to the very large diversity of CrI and lignin contents detected in the collected sugarcane samples, seven high-quality calibration models were developed through online NIRS calibration. All of the generated equations displayed coefficient of determination (R2) values greater than 0.8 and high ratio performance deviation (RPD) values of over 2.0 in calibration, internal cross-validation, and external validation. Remarkably, the equations for CrI and total lignin content exhibited RPD values as high as 2.56 and 2.55, respectively, indicating their excellent prediction capacity. An offline NIRS assay was also performed. Comparable calibration was observed between the offline and online NIRS analyses, suggesting that both strategies would be applicable to estimate cell wall characteristics. Nevertheless, as online NIRS assays offer tremendous advantages for large-scale real-time screening applications, it could be implied that they are a better option for high-throughput cell wall feature prediction. CONCLUSIONS This study, as an initial attempt, explored an online NIRS assay for the high-throughput assessment of key cell wall features in terms of CrI, lignin content, and their proportion in sugarcane. Consistent and precise calibration results were obtained with NIRS modeling, insinuating this strategy as a reliable approach for the large-scale screening of promising sugarcane germplasm for cell wall structure improvement and beyond.
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Affiliation(s)
- Xinru Li
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Fumin Ma
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Chengping Liang
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Maoyao Wang
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Yan Zhang
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Yufei Shen
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Muhammad Adnan
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Pan Lu
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China
| | - Muhammad Tahir Khan
- Sugarcane Biotechnology Group, Nuclear Institute of Agriculture (NIA), Tando Jam, Pakistan
| | - Jiangfeng Huang
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China.
| | - Muqing Zhang
- Guangxi Key Laboratory of Sugarcane Biology, Sugar Industry Collaborative Innovation Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, Guangxi, China.
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16
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Hodgson-Kratky K, Perlo V, Furtado A, Choudhary H, Gladden JM, Simmons BA, Botha F, Henry RJ. Association of gene expression with syringyl to guaiacyl ratio in sugarcane lignin. PLANT MOLECULAR BIOLOGY 2021; 106:173-192. [PMID: 33738678 DOI: 10.1007/s11103-021-01136-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 03/02/2021] [Indexed: 05/11/2023]
Abstract
A transcriptome analysis reveals the transcripts and alleles differentially expressed in sugarcane genotypes with contrasting lignin composition. Sugarcane bagasse is a highly abundant resource that may be used as a feedstock for the production of biofuels and bioproducts in order to meet increasing demands for renewable replacements for fossil carbon. However, lignin imparts rigidity to the cell wall that impedes the efficient breakdown of the biomass into fermentable sugars. Altering the ratio of the lignin units, syringyl (S) and guaiacyl (G), which comprise the native lignin polymer in sugarcane, may facilitate the processing of bagasse. This study aimed to identify genes and markers associated with S/G ratio in order to accelerate the development of sugarcane bioenergy varieties with modified lignin composition. The transcriptome sequences of 12 sugarcane genotypes that contrasted for S/G ratio were compared and there were 2019 transcripts identified as differentially expressed (DE) between the high and low S/G ratio groups. These included transcripts encoding possible monolignol biosynthetic pathway enzymes, transporters, dirigent proteins and transcriptional and post-translational regulators. Furthermore, the frequencies of single nucleotide polymorphisms (SNPs) were compared between the low and high S/G ratio groups to identify specific alleles expressed with the phenotype. There were 2063 SNP loci across 787 unique transcripts that showed group-specific expression. Overall, the DE transcripts and SNP alleles identified in this study may be valuable for breeding sugarcane varieties with altered S/G ratio that may provide desirable bioenergy traits.
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Affiliation(s)
- K Hodgson-Kratky
- Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD, 4072, Australia
| | - V Perlo
- Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD, 4072, Australia
| | - A Furtado
- Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD, 4072, Australia
| | - H Choudhary
- Joint BioEnergy Institute, Emeryville, CA, 94608, USA
- Sandia National Laboratories, Livermore, CA, 94550, USA
| | - J M Gladden
- Joint BioEnergy Institute, Emeryville, CA, 94608, USA
- Sandia National Laboratories, Livermore, CA, 94550, USA
| | - B A Simmons
- Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD, 4072, Australia
- Joint BioEnergy Institute, Emeryville, CA, 94608, USA
- Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - F Botha
- Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD, 4072, Australia
| | - R J Henry
- Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, QLD, 4072, Australia.
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Genome-wide analysis of general phenylpropanoid and monolignol-specific metabolism genes in sugarcane. Funct Integr Genomics 2021; 21:73-99. [PMID: 33404914 DOI: 10.1007/s10142-020-00762-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 11/23/2020] [Accepted: 11/27/2020] [Indexed: 10/22/2022]
Abstract
Lignin is the main component of secondary cell walls and is essential for plant development and defense. However, lignin is recognized as a major recalcitrant factor for efficiency of industrial biomass processing. Genes involved in general phenylpropanoid and monolignol-specific metabolism in sugarcane have been previously analyzed at the transcriptomic level. Nevertheless, the number of genes identified in this species is still very low. The recently released sugarcane genome sequence has allowed the genome-wide characterization of the 11 gene families involved in the monolignol biosynthesis branch of the phenylpropanoid pathway. After an exhaustive analysis of sugarcane genomes, 438 haplotypes derived from 175 candidate genes from Saccharum spontaneum and 144 from Saccharum hybrid R570 were identified as associated with this biosynthetic route. The phylogenetic analyses, combined with the search for protein conserved residues involved in the catalytic activity of the encoded enzymes, were employed to identify the family members potentially involved in developmental lignification. Accordingly, 15 candidates were identified as bona fide lignin biosynthesis genes: PTAL1, PAL2, C4H4, 4CL1, HCT1, HCT2, C3'H1, C3'H2, CCoAOMT1, COMT1, F5H1, CCR1, CCR2, CAD2, and CAD7. For this core set of lignin biosynthetic genes, we searched for the chromosomal location, the gene expression pattern, the promoter cis-acting elements, and microRNA targets. Altogether, our results present a comprehensive characterization of sugarcane general phenylpropanoid and monolignol-specific genes, providing the basis for further functional studies focusing on lignin biosynthesis manipulation and biotechnological strategies to improve sugarcane biomass utilization.
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18
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Calderan-Rodrigues MJ, de Barros Dantas LL, Cheavegatti Gianotto A, Caldana C. Applying Molecular Phenotyping Tools to Explore Sugarcane Carbon Potential. FRONTIERS IN PLANT SCIENCE 2021; 12:637166. [PMID: 33679852 PMCID: PMC7935522 DOI: 10.3389/fpls.2021.637166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 01/27/2021] [Indexed: 05/21/2023]
Abstract
Sugarcane (Saccharum spp.), a C4 grass, has a peculiar feature: it accumulates, gradient-wise, large amounts of carbon (C) as sucrose in its culms through a complex pathway. Apart from being a sustainable crop concerning C efficiency and bioenergetic yield per hectare, sugarcane is used as feedstock for producing ethanol, sugar, high-value compounds, and products (e.g., polymers and succinate), and bioelectricity, earning the title of the world's leading biomass crop. Commercial cultivars, hybrids bearing high levels of polyploidy, and aneuploidy, are selected from a large number of crosses among suitable parental genotypes followed by the cloning of superior individuals among the progeny. Traditionally, these classical breeding strategies have been favoring the selection of cultivars with high sucrose content and resistance to environmental stresses. A current paradigm change in sugarcane breeding programs aims to alter the balance of C partitioning as a means to provide more plasticity in the sustainable use of this biomass for metabolic engineering and green chemistry. The recently available sugarcane genetic assemblies powered by data science provide exciting perspectives to increase biomass, as the current sugarcane yield is roughly 20% of its predicted potential. Nowadays, several molecular phenotyping tools can be applied to meet the predicted sugarcane C potential, mainly targeting two competing pathways: sucrose production/storage and biomass accumulation. Here we discuss how molecular phenotyping can be a powerful tool to assist breeding programs and which strategies could be adopted depending on the desired final products. We also tackle the advances in genetic markers and mapping as well as how functional genomics and genetic transformation might be able to improve yield and saccharification rates. Finally, we review how "omics" advances are promising to speed up plant breeding and reach the unexplored potential of sugarcane in terms of sucrose and biomass production.
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Affiliation(s)
| | | | | | - Camila Caldana
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- *Correspondence: Camila Caldana,
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19
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Abstract
RNA interference (RNAi) is an innate cellular mechanism triggered by a double-stranded RNA (dsRNA) molecule causing selective inhibition of gene expression. Here, we demonstrated the RNAi technology for gene silencing in sugarcane for biofuel production. This chapter describes an efficient model system that established to target the caffeic acid O-methyltransferase (COMT) gene and the RNAi construct is designed and delivered through Agrobacterium mediated stable sugarcane transformation. Also, the approach for an analysis of resulting putative transgenic plants for a targeted RNAi mediated gene silencing is described.
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Affiliation(s)
- Naveenarani Murugan
- Division of Crop Improvement, ICAR-Sugarcane Breeding Institute, Coimbatore, India
| | - Chakravarthi Mohan
- Agronomy Department, IFAS, University of Florida, Gainesville, FL, USA
- Department of Genetics and Evolution, Federal University of São Carlos, São Carlos, SP, Brazil
| | - Baskaran Kannan
- Agronomy Department, IFAS, University of Florida, Gainesville, FL, USA.
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20
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Jardim-Messeder D, da Franca Silva T, Fonseca JP, Junior JN, Barzilai L, Felix-Cordeiro T, Pereira JC, Rodrigues-Ferreira C, Bastos I, da Silva TC, de Abreu Waldow V, Cassol D, Pereira W, Flausino B, Carniel A, Faria J, Moraes T, Cruz FP, Loh R, Van Montagu M, Loureiro ME, de Souza SR, Mangeon A, Sachetto-Martins G. Identification of genes from the general phenylpropanoid and monolignol-specific metabolism in two sugarcane lignin-contrasting genotypes. Mol Genet Genomics 2020; 295:717-739. [PMID: 32124034 DOI: 10.1007/s00438-020-01653-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/12/2020] [Indexed: 11/29/2022]
Abstract
The phenylpropanoid pathway is an important route of secondary metabolism involved in the synthesis of different phenolic compounds such as phenylpropenes, anthocyanins, stilbenoids, flavonoids, and monolignols. The flux toward monolignol biosynthesis through the phenylpropanoid pathway is controlled by specific genes from at least ten families. Lignin polymer is one of the major components of the plant cell wall and is mainly responsible for recalcitrance to saccharification in ethanol production from lignocellulosic biomass. Here, we identified and characterized sugarcane candidate genes from the general phenylpropanoid and monolignol-specific metabolism through a search of the sugarcane EST databases, phylogenetic analysis, a search for conserved amino acid residues important for enzymatic function, and analysis of expression patterns during culm development in two lignin-contrasting genotypes. Of these genes, 15 were cloned and, when available, their loci were identified using the recently released sugarcane genomes from Saccharum hybrid R570 and Saccharum spontaneum cultivars. Our analysis points out that ShPAL1, ShPAL2, ShC4H4, Sh4CL1, ShHCT1, ShC3H1, ShC3H2, ShCCoAOMT1, ShCOMT1, ShF5H1, ShCCR1, ShCAD2, and ShCAD7 are strong candidates to be bona fide lignin biosynthesis genes. Together, the results provide information about the candidate genes involved in monolignol biosynthesis in sugarcane and may provide useful information for further molecular genetic studies in sugarcane.
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Affiliation(s)
- Douglas Jardim-Messeder
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tatiane da Franca Silva
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, São Paulo, Brazil
| | - Jose Pedro Fonseca
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - José Nicomedes Junior
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Centro de Pesquisa e Desenvolvimento Leopoldo Américo Miguez de Mello, Gerência de Biotecnologia, CENPES, Petrobras, Rio de Janeiro, Brazil
| | - Lucia Barzilai
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thais Felix-Cordeiro
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Joyce Carvalho Pereira
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Clara Rodrigues-Ferreira
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isabela Bastos
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tereza Cristina da Silva
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vinicius de Abreu Waldow
- Centro de Pesquisa e Desenvolvimento Leopoldo Américo Miguez de Mello, Gerência de Biotecnologia, CENPES, Petrobras, Rio de Janeiro, Brazil
| | - Daniela Cassol
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Willian Pereira
- Departamento de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Bruno Flausino
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Adriano Carniel
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Centro de Pesquisa e Desenvolvimento Leopoldo Américo Miguez de Mello, Gerência de Biotecnologia, CENPES, Petrobras, Rio de Janeiro, Brazil
| | - Jessica Faria
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thamirys Moraes
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fernanda P Cruz
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Roberta Loh
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Instituto Federal de Educação, Ciência e Tecnologia do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marc Van Montagu
- Institute of Plant Biotechnology Outreach, Gent University, Technologiepark 3, Zwijnaarde, 9052, Gent, Belgium
| | - Marcelo Ehlers Loureiro
- Laboratório de Fisiologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Sonia Regina de Souza
- Departamento de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Amanda Mangeon
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Gilberto Sachetto-Martins
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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21
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Shimizu FL, Zamora HDZ, Schmatz AA, Melati RB, Bueno D, Brienzo M. Biofuels Generation Based on Technical Process and Biomass Quality. CLEAN ENERGY PRODUCTION TECHNOLOGIES 2020. [DOI: 10.1007/978-981-13-8637-4_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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22
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OsCAldOMT1 is a bifunctional O-methyltransferase involved in the biosynthesis of tricin-lignins in rice cell walls. Sci Rep 2019; 9:11597. [PMID: 31406182 PMCID: PMC6690965 DOI: 10.1038/s41598-019-47957-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 07/26/2019] [Indexed: 01/26/2023] Open
Abstract
Lignin is a phenylpropanoid polymer produced in the secondary cell walls of vascular plants. Although most eudicot and gymnosperm species generate lignins solely via polymerization of p-hydroxycinnamyl alcohols (monolignols), grasses additionally use a flavone, tricin, as a natural lignin monomer to generate tricin-incorporated lignin polymers in cell walls. We previously found that disruption of a rice 5-HYDROXYCONIFERALDEHYDE O-METHYLTRANSFERASE (OsCAldOMT1) reduced extractable tricin-type metabolites in rice vegetative tissues. This same enzyme has also been implicated in the biosynthesis of sinapyl alcohol, a monolignol that constitutes syringyl lignin polymer units. Here, we further demonstrate through in-depth cell wall structural analyses that OsCAldOMT1-deficient rice plants produce altered lignins largely depleted in both syringyl and tricin units. We also show that recombinant OsCAldOMT1 displayed comparable substrate specificities towards both 5-hydroxyconiferaldehyde and selgin intermediates in the monolignol and tricin biosynthetic pathways, respectively. These data establish OsCAldOMT1 as a bifunctional O-methyltransferase predominantly involved in the two parallel metabolic pathways both dedicated to the biosynthesis of tricin-lignins in rice cell walls. Given that cell wall digestibility was greatly enhanced in the OsCAldOMT1-deficient rice plants, genetic manipulation of CAldOMTs conserved in grasses may serve as a potent strategy to improve biorefinery applications of grass biomass.
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23
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Low Lignin Mutants and Reduction of Lignin Content in Grasses for Increased Utilisation of Lignocellulose. AGRONOMY-BASEL 2019. [DOI: 10.3390/agronomy9050256] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Biomass rich in lignocellulose from grasses is a major source for biofuel production and animal feed. However, the presence of lignin in cell walls limits its efficient utilisation such as in its bioconversion to biofuel. Reduction of the lignin content or alteration of its structure in crop plants have been pursued, either by regulating genes encoding enzymes in the lignin biosynthetic pathway using biotechnological techniques or by breeding naturally-occurring low lignin mutant lines. The aim of this review is to provide a summary of these studies, focusing on lignin (monolignol) biosynthesis and composition in grasses and, where possible, the impact on recalcitrance to bioconversion. An overview of transgenic crops of the grass family with regulated gene expression in lignin biosynthesis is presented, including the effect on lignin content and changes in the ratio of p-hydroxyphenyl (H), guaiacyl (G) and syringyl (S) units. Furthermore, a survey is provided of low-lignin mutants in grasses, including cereals in particular, summarising their origin and phenotypic traits together with genetics and the molecular function of the various genes identified.
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24
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Pazhany AS, Henry RJ. Genetic Modification of Biomass to Alter Lignin Content and Structure. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b01163] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Adhini S. Pazhany
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, 4072 Queensland, Australia
- ICAR - Sugarcane Breeding Institute, Coimbatore, 641 007 Tamil Nadu, India
| | - Robert J. Henry
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, 4072 Queensland, Australia
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25
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Abstract
We used primers designed on conserved gene regions of several species to isolate the most expressed genes of the lignin pathway in four Saccharum species. S. officinarum and S. barberi have more sucrose in the culms than S. spontaneum and S. robustum, but less polysaccharides and lignin in the cell wall. S. spontaneum, and S. robustum had the lowest S/G ratio and a lower rate of saccharification in mature internodes. Surprisingly, except for CAD, 4CL, and CCoAOMT for which we found three, two, and two genes, respectively, only one gene was found for the other enzymes and their sequences were highly similar among the species. S. spontaneum had the highest expression for most genes. CCR and CCoAOMT B presented the highest expression; 4CL and F5H showed increased expression in mature tissues; C3H and CCR had higher expression in S. spontaneum, and one of the CADs isolated (CAD B) had higher expression in S. officinarum. The similarity among the most expressed genes isolated from these species was unexpected and indicated that lignin biosynthesis is conserved in Saccharum including commercial varieties Thus the lignin biosynthesis control in sugarcane may be only fully understood with the knowledge of the promotor region of each gene.
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26
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Wu Z, Wang N, Hisano H, Cao Y, Wu F, Liu W, Bao Y, Wang Z, Fu C. Simultaneous regulation of F5H in COMT-RNAi transgenic switchgrass alters effects of COMT suppression on syringyl lignin biosynthesis. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:836-845. [PMID: 30267599 PMCID: PMC6419721 DOI: 10.1111/pbi.13019] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 09/12/2018] [Accepted: 09/24/2018] [Indexed: 05/06/2023]
Abstract
Ferulate 5-hydroxylase (F5H) catalyses the hydroxylation of coniferyl alcohol and coniferaldehyde for the biosynthesis of syringyl (S) lignin in angiosperms. However, the coordinated effects of F5H with caffeic acid O-methyltransferase (COMT) on the metabolic flux towards S units are largely unknown. We concomitantly regulated F5H expression in COMT-down-regulated transgenic switchgrass (Panicum virgatum L.) lines and studied the coordination of F5H and COMT in lignin biosynthesis. Down-regulation of F5H in COMT-RNAi transgenic switchgrass plants further impeded S lignin biosynthesis and, consequently, increased guaiacyl (G) units and reduced 5-OH G units. Conversely, overexpression of F5H in COMT-RNAi transgenic plants reduced G units and increased 5-OH units, whereas the deficiency of S lignin biosynthesis was partially compensated or fully restored, depending on the extent of COMT down-regulation in switchgrass. Moreover, simultaneous regulation of F5H and COMT expression had different effects on cell wall digestibility of switchgrass without biomass loss. Our results indicate that up-regulation and down-regulation of F5H expression, respectively, have antagonistic and synergistic effects on the reduction in S lignin resulting from COMT suppression. The coordinated effects between lignin genes should be taken into account in future studies aimed at cell wall bioengineering.
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Affiliation(s)
- Zhenying Wu
- Shandong Provincial Key Laboratory of Energy GeneticsKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Nengfei Wang
- Key Lab of Marine Bioactive SubstancesThe First Institute of OceanographyState Oceanic AdministrationQingdaoShandongChina
| | - Hiroshi Hisano
- Noble Research Institute, LLCArdmoreOKUSA
- Institute of Plant Science and ResourcesOkayama UniversityKurashikiOkayamaJapan
| | - Yingping Cao
- Shandong Provincial Key Laboratory of Energy GeneticsKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Fengyan Wu
- Noble Research Institute, LLCArdmoreOKUSA
| | - Wenwen Liu
- Shandong Provincial Key Laboratory of Energy GeneticsKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Yan Bao
- Shandong Provincial Key Laboratory of Energy GeneticsKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | | | - Chunxiang Fu
- Shandong Provincial Key Laboratory of Energy GeneticsKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
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27
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Daly P, McClellan C, Maluk M, Oakey H, Lapierre C, Waugh R, Stephens J, Marshall D, Barakate A, Tsuji Y, Goeminne G, Vanholme R, Boerjan W, Ralph J, Halpin C. RNAi-suppression of barley caffeic acid O-methyltransferase modifies lignin despite redundancy in the gene family. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:594-607. [PMID: 30133138 PMCID: PMC6381794 DOI: 10.1111/pbi.13001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 08/18/2018] [Indexed: 05/12/2023]
Abstract
Caffeic acid O-methyltransferase (COMT), the lignin biosynthesis gene modified in many brown-midrib high-digestibility mutants of maize and sorghum, was targeted for downregulation in the small grain temperate cereal, barley (Hordeum vulgare), to improve straw properties. Phylogenetic and expression analyses identified the barley COMT orthologue(s) expressed in stems, defining a larger gene family than in brachypodium or rice with three COMT genes expressed in lignifying tissues. RNAi significantly reduced stem COMT protein and enzyme activity, and modestly reduced stem lignin content while dramatically changing lignin structure. Lignin syringyl-to-guaiacyl ratio was reduced by ~50%, the 5-hydroxyguaiacyl (5-OH-G) unit incorporated into lignin at 10--15-fold higher levels than normal, and the amount of p-coumaric acid ester-linked to cell walls was reduced by ~50%. No brown-midrib phenotype was observed in any RNAi line despite significant COMT suppression and altered lignin. The novel COMT gene family structure in barley highlights the dynamic nature of grass genomes. Redundancy in barley COMTs may explain the absence of brown-midrib mutants in barley and wheat. The barley COMT RNAi lines nevertheless have the potential to be exploited for bioenergy applications and as animal feed.
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Affiliation(s)
- Paul Daly
- Division of Plant SciencesSchool of Life SciencesUniversity of Dundee at the James Hutton InstituteDundeeUK
- Present address:
Fungal PhysiologyWesterdijk Fungal Biodiversity Institute and Fungal Molecular PhysiologyUtrecht UniversityUtrechtThe Netherlands
| | - Christopher McClellan
- Division of Plant SciencesSchool of Life SciencesUniversity of Dundee at the James Hutton InstituteDundeeUK
| | - Marta Maluk
- Division of Plant SciencesSchool of Life SciencesUniversity of Dundee at the James Hutton InstituteDundeeUK
| | - Helena Oakey
- Division of Plant SciencesSchool of Life SciencesUniversity of Dundee at the James Hutton InstituteDundeeUK
- Faculty of SciencesSchool of Agriculture, Food and WineUniversity of AdelaideAdelaideAustralia
| | - Catherine Lapierre
- UMR1318 INRA‐AgroParistechIJPBUniversite Paris‐SaclayVersailles CedexFrance
| | - Robbie Waugh
- Division of Plant SciencesSchool of Life SciencesUniversity of Dundee at the James Hutton InstituteDundeeUK
- Cell and Molecular SciencesJames Hutton InstituteDundeeUK
| | | | - David Marshall
- Information and Computational SciencesJames Hutton InstituteDundeeUK
| | - Abdellah Barakate
- Division of Plant SciencesSchool of Life SciencesUniversity of Dundee at the James Hutton InstituteDundeeUK
| | - Yukiko Tsuji
- Department of BiochemistryUniversity of Wisconsin‐MadisonMadisonWIUSA
- Department of Energy's Great Lakes Bioenergy Research CenterThe Wisconsin Energy InstituteUniversity of Wisconsin‐MadisonMadisonWIUSA
| | - Geert Goeminne
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGhentBelgium
- VIB Center for Plant Systems BiologyGhentBelgium
| | - Ruben Vanholme
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGhentBelgium
- VIB Center for Plant Systems BiologyGhentBelgium
| | - Wout Boerjan
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGhentBelgium
- VIB Center for Plant Systems BiologyGhentBelgium
| | - John Ralph
- Department of BiochemistryUniversity of Wisconsin‐MadisonMadisonWIUSA
- Department of Energy's Great Lakes Bioenergy Research CenterThe Wisconsin Energy InstituteUniversity of Wisconsin‐MadisonMadisonWIUSA
| | - Claire Halpin
- Division of Plant SciencesSchool of Life SciencesUniversity of Dundee at the James Hutton InstituteDundeeUK
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28
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Figueiredo R, Araújo P, Llerena JPP, Mazzafera P. Suberin and hemicellulose in sugarcane cell wall architecture and crop digestibility: A biotechnological perspective. Food Energy Secur 2019. [DOI: 10.1002/fes3.163] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Raquel Figueiredo
- Department of Plant Biology Institute of Biology State University of Campinas Campinas Brazil
| | - Pedro Araújo
- Department of Genetics, Evolution and Bioagents Institute of Biology State University of Campinas Campinas Brazil
| | - Juan Pablo P. Llerena
- Department of Plant Biology Institute of Biology State University of Campinas Campinas Brazil
| | - Paulo Mazzafera
- Department of Plant Biology Institute of Biology State University of Campinas Campinas Brazil
- Department of Crop Science College of Agriculture Luiz de Queiroz University of São Paulo Piracicaba Brazil
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29
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Llerena JPP, Araújo P, Mazzafera P. Optimization of RT-PCR reactions in studies with genes of lignin biosynthetic route in Saccharum spontaneum. AN ACAD BRAS CIENC 2018; 90:509-519. [PMID: 29641770 DOI: 10.1590/0001-3765201820170250] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/19/2017] [Indexed: 11/22/2022] Open
Abstract
Saccharum spontaneum has been used for the development of energy cane a crop aimed to be used for the production of second-generation ethanol, or lignocellulosic ethanol. Lignin is a main challenge in the conversion of cell wall sugars into ethanol. In our studies to isolate the genes the lignin biosynthesis in S. spontaneum we have had great difficulty in RT-PCR reactions. Thus, we evaluated the effectiveness of different additives in the amplification of these genes. While COMT and CCoAOMT genes did not need any additives for other genes there was no amplification (HCT, F5H, 4CL and CCR) or the yield was very low (CAD and C4H). The application of supplementary cDNA was enough to overcome the non-specificity and low yield for C4H and C3H, while the addition of 0.04% BSA + 2% formamide was effective to amplify 4CL, CCR, F5H and CCR. HCT was amplified only by addition of 0.04% BSA + 2% formamide + 0.1 M trehalose and amplification of PAL was possible with addition of 2% of DMSO. Besides optimization of expression assays, the results show that additives can act independently or synergistically.
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Affiliation(s)
- Juan P P Llerena
- Universidade Estadual de Campinas, Laboratório de Fisiologia Molecular das Plantas, Departamento de Biologia Vegetal, Instituto de Biologia, Rua Monteiro Lobato, 255, Caixa Postal 6109, 13083-862 Campinas, SP, Brazil
| | - Pedro Araújo
- Universidade Estadual de Campinas, Laboratório de Genoma Funcional, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Rua Monteiro Lobato, 255, 13083-862 Campinas, SP, Brazil
| | - Paulo Mazzafera
- Universidade Estadual de Campinas, Laboratório de Fisiologia Molecular das Plantas, Departamento de Biologia Vegetal, Instituto de Biologia, Rua Monteiro Lobato, 255, Caixa Postal 6109, 13083-862 Campinas, SP, Brazil.,Universidade de São Paulo, Escola Superior de Agricultura Luiz de Queiroz, Departamento de Produção Vegetal, Av. Pádua Dias, 11, Caixa Postal 9, 34294-100 Piracicaba, SP, Brazil
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30
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Kannan B, Jung JH, Moxley GW, Lee S, Altpeter F. TALEN-mediated targeted mutagenesis of more than 100 COMT copies/alleles in highly polyploid sugarcane improves saccharification efficiency without compromising biomass yield. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:856-866. [PMID: 28905511 PMCID: PMC5866949 DOI: 10.1111/pbi.12833] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 08/23/2017] [Accepted: 09/01/2017] [Indexed: 05/02/2023]
Abstract
Sugarcane is the world's most efficient feedstock for commercial production of bioethanol due to its superior biomass production and accumulation of sucrose in stems. Integrating first- and second-generation ethanol conversion processes will enhance the biofuel yield per unit area by utilizing both sucrose and cell wall-bound sugars for fermentation. RNAi suppression of the lignin biosynthetic gene caffeic acid O-methyltransferase (COMT) has been demonstrated to improve bioethanol production from lignocellulosic biomass. Genome editing has been used in a number of crops for creation of loss of function phenotypes but is very challenging in sugarcane due to its highly polyploid genome. In this study, a conserved region of COMT was targeted with a single-transcription activator-like effector nuclease (TALEN) pair for multi-allelic mutagenesis to modify lignin biosynthesis in sugarcane. Field-grown TALEN-mediated COMT mutants showed up to 19.7% lignin reduction and significantly decreased syringyl to guaiacyl (S/G) ratio resulting in an up to 43.8% improved saccharification efficiency. Biomass production of COMT mutant lines with superior saccharification efficiency did not differ significantly from the original cultivar under replicated field conditions. Sanger sequencing of cloned COMT amplicons (1351-1657 bp) revealed co-editing of 107 of the 109 unique COMT copies/alleles in vegetative progeny of line CB6 using a single TALEN pair. Line CB6 combined altered cell wall composition and drastically improved saccharification efficiency with good agronomic performance. These findings confirm the feasibility of co-mutagenesis of a very large number of target alleles/copies for improvement in crops with complex genomes.
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Affiliation(s)
- Baskaran Kannan
- Agronomy DepartmentIFAS, University of FloridaGainesvilleFLUSA
| | - Je Hyeong Jung
- Agronomy DepartmentIFAS, University of FloridaGainesvilleFLUSA
- Present address:
Center for Natural Products Convergence ResearchKorea Institute of Science and Technology (KIST)GangneungGangwon‐doSouth Korea
| | | | - Sun‐Mi Lee
- Clean Energy Research CenterKorea Institute of Science and Technology (KIST)SeoulSouth Korea
| | - Fredy Altpeter
- Agronomy DepartmentIFAS, University of FloridaGainesvilleFLUSA
- Plant Molecular and Cellular Biology ProgramIFAS, University of FloridaGainesvilleFLUSA
- Genetics InstituteUniversity of FloridaGainesvilleFLUSA
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31
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Kandel R, Yang X, Song J, Wang J. Potentials, Challenges, and Genetic and Genomic Resources for Sugarcane Biomass Improvement. FRONTIERS IN PLANT SCIENCE 2018; 9:151. [PMID: 29503654 PMCID: PMC5821101 DOI: 10.3389/fpls.2018.00151] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 01/29/2018] [Indexed: 05/07/2023]
Abstract
Lignocellulosic biomass has become an emerging feedstock for second-generation bioethanol production. Sugarcane (Saccharum spp. hybrids), a very efficient perennial C4 plant with a high polyploid level and complex genome, is considered a top-notch candidate for biomass production due to its salient features viz. fast growth rate and abilities for high tillering, ratooning, and photosynthesis. Energy cane, an ideal type of sugarcane, has been bred specifically as a biomass crop. In this review, we described (1) biomass potentials of sugarcane and its underlying genetics, (2) challenges associated with biomass improvement such as large and complex genome, narrow gene pool in existing commercial cultivars, long breeding cycle, and non-synchronous flowering, (3) available genetic resources such as germplasm resources, and genomic and cell wall-related databases that facilitate biomass improvement, and (4) mining candidate genes controlling biomass in genomic databases. We extensively reviewed databases for biomass-related genes and their usefulness in biofuel generation. This review provides valuable resources for sugarcane breeders, geneticists, and broad scientific communities involved in bioenergy production.
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Affiliation(s)
- Ramkrishna Kandel
- Agronomy Department, University of Florida, Gainesville, FL, United States
- Horticultural Sciences Department, University of Florida, Gainesville, FL, United States
| | - Xiping Yang
- Agronomy Department, University of Florida, Gainesville, FL, United States
| | - Jian Song
- Agronomy Department, University of Florida, Gainesville, FL, United States
- College of Life Sciences, Dezhou University, Dezhou, China
| | - Jianping Wang
- Agronomy Department, University of Florida, Gainesville, FL, United States
- FAFU and UIUC-SIB Joint Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems, Fujian Agriculture and Forestry University, Fuzhou, China
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Baxter HL, Mazarei M, Dumitrache A, Natzke JM, Rodriguez M, Gou J, Fu C, Sykes RW, Turner GB, Davis MF, Brown SD, Davison BH, Wang Z, Stewart CN. Transgenic miR156 switchgrass in the field: growth, recalcitrance and rust susceptibility. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:39-49. [PMID: 28436149 PMCID: PMC5785337 DOI: 10.1111/pbi.12747] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 03/16/2017] [Accepted: 04/10/2017] [Indexed: 05/02/2023]
Abstract
Sustainable utilization of lignocellulosic perennial grass feedstocks will be enabled by high biomass production and optimized cell wall chemistry for efficient conversion into biofuels. MicroRNAs are regulatory elements that modulate the expression of genes involved in various biological functions in plants, including growth and development. In greenhouse studies, overexpressing a microRNA (miR156) gene in switchgrass had dramatic effects on plant architecture and flowering, which appeared to be driven by transgene expression levels. High expressing lines were extremely dwarfed, whereas low and moderate-expressing lines had higher biomass yields, improved sugar release and delayed flowering. Four lines with moderate or low miR156 overexpression from the prior greenhouse study were selected for a field experiment to assess the relationship between miR156 expression and biomass production over three years. We also analysed important bioenergy feedstock traits such as flowering, disease resistance, cell wall chemistry and biofuel production. Phenotypes of the transgenic lines were inconsistent between the greenhouse and the field as well as among different field growing seasons. One low expressing transgenic line consistently produced more biomass (25%-56%) than the control across all three seasons, which translated to the production of 30% more biofuel per plant during the final season. The other three transgenic lines produced less biomass than the control by the final season, and the two lines with moderate expression levels also exhibited altered disease susceptibilities. Results of this study emphasize the importance of performing multiyear field studies for plants with altered regulatory transgenes that target plant growth and development.
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Affiliation(s)
- Holly L. Baxter
- Department of Plant SciencesUniversity of TennesseeKnoxvilleTNUSA
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
| | - Mitra Mazarei
- Department of Plant SciencesUniversity of TennesseeKnoxvilleTNUSA
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
| | - Alexandru Dumitrache
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTNUSA
| | - Jace M. Natzke
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTNUSA
| | - Miguel Rodriguez
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTNUSA
| | - Jiqing Gou
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Samuel Roberts Noble FoundationArdmoreOKUSA
| | - Chunxiang Fu
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Samuel Roberts Noble FoundationArdmoreOKUSA
| | - Robert W. Sykes
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- National Renewable Energy LaboratoryGoldenCOUSA
| | - Geoffrey B. Turner
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- National Renewable Energy LaboratoryGoldenCOUSA
| | - Mark F. Davis
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- National Renewable Energy LaboratoryGoldenCOUSA
| | - Steven D. Brown
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTNUSA
| | - Brian H. Davison
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTNUSA
| | - Zeng‐Yu Wang
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
- Samuel Roberts Noble FoundationArdmoreOKUSA
| | - C. Neal Stewart
- Department of Plant SciencesUniversity of TennesseeKnoxvilleTNUSA
- BioEnergy Science Center (BESC)Oak Ridge National LaboratoryOak RidgeTNUSA
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Wai CM, Zhang J, Jones TC, Nagai C, Ming R. Cell wall metabolism and hexose allocation contribute to biomass accumulation in high yielding extreme segregants of a Saccharum interspecific F2 population. BMC Genomics 2017; 18:773. [PMID: 29020919 PMCID: PMC5637070 DOI: 10.1186/s12864-017-4158-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 10/05/2017] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Sugarcane is an emerging dual-purpose biofuel crop for energy and sugar production, owing to its rapid growth rate, high sucrose storage in the stems, and high lignocellulosic yield. It has the highest biomass production reaching 1.9 billion tonnes in 2014 worldwide. RESULTS To improve sugarcane biomass accumulation, we developed an interspecific cross between Saccharum officinarum 'LA Purple' and Saccharum robustum 'MOL5829'. Selected F1 individuals were self-pollinated to generate a transgressive F2 population with a wide range of biomass yield. Leaf and stem internodes of fourteen high biomass and eight low biomass F2 extreme segregants were used for RNA-seq to decipher the molecular mechanism of rapid plant growth and dry weight accumulation. Gene Ontology terms involved in cell wall metabolism and carbohydrate catabolism were enriched among 3274 differentially expressed genes between high and low biomass groups. Up-regulation of cellulose metabolism, pectin degradation and lignin biosynthesis genes were observed in the high biomass group, in conjunction with higher transcript levels of callose metabolic genes and the cell wall loosening enzyme expansin. Furthermore, UDP-glucose biosynthesis and sucrose conversion genes were differentially expressed between the two groups. A positive correlation between stem glucose, but not sucrose, levels and dry weight was detected. CONCLUSIONS We thus postulated that the high biomass sugarcane plants rapidly convert sucrose to UDP-glucose, which is the building block of cell wall polymers and callose, in order to maintain the rapid plant growth. The gene interaction of cell wall metabolism, hexose allocation and cell division contributes to biomass yield.
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Affiliation(s)
- Ching Man Wai
- FAFU and UIUC-SIB Joint Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Corps, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002 China
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Jisen Zhang
- FAFU and UIUC-SIB Joint Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Corps, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002 China
| | | | | | - Ray Ming
- FAFU and UIUC-SIB Joint Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Key Laboratory of Genetics, Breeding and Multiple Utilization of Corps, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002 China
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL USA
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Napoleão TA, Soares G, Vital CE, Bastos C, Castro R, Loureiro ME, Giordano A. Methyl jasmonate and salicylic acid are able to modify cell wall but only salicylic acid alters biomass digestibility in the model grass Brachypodium distachyon. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 263:46-54. [PMID: 28818383 DOI: 10.1016/j.plantsci.2017.06.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 06/28/2017] [Accepted: 06/30/2017] [Indexed: 06/07/2023]
Abstract
In addition to playing a key role in the response to environmental changes, cell walls are also considered as a valuable feedstock for cellulosic ethanol. Here we explored the effects of the stress-response hormones, salicylic acid and methyl jasmonate, on cell wall biosynthesis and biomass digestibility in Brachypodium distachyon, a species recently considered as a suitable model for biomass conversion. We found that in response to salicylic acid or methyl jasmonate treatment, plant growth was reduced coupled with significant changes in cell wall composition. Cellulose content increased in response to methyl jasmonate whereas a reduction in lignin content was found after salicylic acid application. Moreover, hemicellulose composition was altered and increases in caffeic acid, ferulic acid and p-coumaric acid content were detected in response to both treatments. The hormonal profile and the expression pattern of genes involved in cell wall biosynthesis were also modified. Biomass digestibility was reduced in leaf tissue after salicylic acid treatment and was negatively correlated with ferulic acid and p-coumaric acid content. The results obtained here aid in our understanding of cell wall dynamics in response to stress and will enable the development of new strategies to improve cell wall digestibility in bioenergy feedstock.
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Affiliation(s)
- Thiago Alves Napoleão
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Giuliana Soares
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Camilo Elber Vital
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Carla Bastos
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Robson Castro
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Marcelo Ehlers Loureiro
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Andrea Giordano
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
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SbCOMT (Bmr12) is involved in the biosynthesis of tricin-lignin in sorghum. PLoS One 2017; 12:e0178160. [PMID: 28594846 PMCID: PMC5464547 DOI: 10.1371/journal.pone.0178160] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 05/09/2017] [Indexed: 11/19/2022] Open
Abstract
Lignin in plant biomass represents a target for engineering strategies towards the development of a sustainable bioeconomy. In addition to the conventional lignin monomers, namely p-coumaryl, coniferyl and sinapyl alcohols, tricin has been shown to be part of the native lignin polymer in certain monocot species. Because tricin is considered to initiate the polymerization of lignin chains, elucidating its biosynthesis and mechanism of export to the cell wall constitute novel challenges for the engineering of bioenergy crops. Late steps of tricin biosynthesis require two methylation reactions involving the pathway intermediate selgin. It has recently been demonstrated in rice and maize that caffeate O-methyltransferase (COMT) involved in the synthesis syringyl (S) lignin units derived from sinapyl alcohol also participates in the synthesis of tricin in planta. In this work, we validate in sorghum (Sorghum bicolor L.) that the O-methyltransferase responsible for the production of S lignin units (SbCOMT / Bmr12) is also involved in the synthesis of lignin-linked tricin. In particular, we show that biomass from the sorghum bmr12 mutant contains lower level of tricin incorporated into lignin, and that SbCOMT can methylate the tricin precursors luteolin and selgin. Our genetic and biochemical data point toward a general mechanism whereby COMT is involved in the synthesis of both tricin and S lignin units.
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Lee MB, Kim JY, Seo YW. Identification of lignin-deficient Brachypodium distachyon (L.) Beauv. mutants induced by gamma radiation. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2017; 97:2159-2165. [PMID: 27604502 DOI: 10.1002/jsfa.8024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/24/2016] [Accepted: 09/02/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Brachypodium distachyon (L.) Beauv. is a monocotyledonous model plant that has been studied to understand a range of biological phenomena for lignocellulosic bioethanol feedstocks and other cereal crops. The lignin makes its cell walls recalcitrant to saccharification, constituting the main barrier to lignocellulosic bioethanol production. In this study, lignin-deficient mutants of B. distachyon induced by chronic radiation were selected and the effects of the mutants on fermentable glucose production were identified. RESULTS Brachypodium distachyon M2 mutants induced by chronically irradiated gamma radiation were screened by the Wiesner test. Lignin-deficient M2 mutants were further confirmed in subsequent M3 and M4 generations by determining acetyl bromide-soluble lignin. The lignin content was significantly reduced in mutant plants 135-2 (by 7.99%), 142-3 (by 13.8%) and 406-1 (by 8.13%) compared with the wild type. Moreover, fermentable glucose was significantly higher in 135-2 (by 23.91%) and 142-3 (by 36.72%) than in the wild type after 72 h of enzymatic hydrolysis. CONCLUSION Three lignin-deficient B. distachyon mutants induced by chronically irradiated gamma radiation were obtained. This study will provide fundamental understanding of the B. distachyon cell wall and could contribute to increases in bioethanol production using bioenergy crops. © 2016 Society of Chemical Industry.
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Affiliation(s)
- Man Bo Lee
- Department of Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul, 136-713, Korea
| | - Jae Yoon Kim
- Department of Biosystems and Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul, 136-713, Korea
| | - Yong Weon Seo
- Department of Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul, 136-713, Korea
- Department of Biosystems and Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul, 136-713, Korea
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Kim JY, Nong G, Rice JD, Gallo M, Preston JF, Altpeter F. In planta production and characterization of a hyperthermostable GH10 xylanase in transgenic sugarcane. PLANT MOLECULAR BIOLOGY 2017; 93:465-478. [PMID: 28005227 DOI: 10.1007/s11103-016-0573-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 12/04/2016] [Indexed: 06/06/2023]
Abstract
Sugarcane (Saccharum sp. hybrids) is one of the most efficient and sustainable feedstocks for commercial production of fuel ethanol. Recent efforts focus on the integration of first and second generation bioethanol conversion technologies for sugarcane to increase biofuel yields. This integrated process will utilize both the cell wall bound sugars of the abundant lignocellulosic sugarcane residues in addition to the sucrose from stem internodes. Enzymatic hydrolysis of lignocellulosic biomass into its component sugars requires significant amounts of cell wall degrading enzymes. In planta production of xylanases has the potential to reduce costs associated with enzymatic hydrolysis but has been reported to compromise plant growth and development. To address this problem, we expressed a hyperthermostable GH10 xylanase, xyl10B in transgenic sugarcane which displays optimal catalytic activity at 105 °C and only residual catalytic activity at temperatures below 70 °C. Transgene integration and expression in sugarcane were confirmed by Southern blot, RT-PCR, ELISA and western blot following biolistic co-transfer of minimal expression cassettes of xyl10B and the selectable neomycin phosphotransferase II. Xylanase activity was detected in 17 transgenic lines with a fluorogenic xylanase activity assay. Up to 1.2% of the total soluble protein fraction of vegetative progenies with integration of chloroplast targeted expression represented the recombinant Xyl10B protein. Xyl10B activity was stable in vegetative progenies. Tissues retained 75% of the xylanase activity after drying of leaves at 35 °C and a 2 month storage period. Transgenic sugarcane plants producing Xyl10B did not differ from non-transgenic sugarcane in growth and development under greenhouse conditions. Sugarcane xylan and bagasse were used as substrate for enzymatic hydrolysis with the in planta produced Xyl10B. TLC and HPLC analysis of hydrolysis products confirmed the superior catalytic activity and stability of the in planta produced Xyl10B with xylobiose as a prominent degradation product. These findings will contribute to advancing consolidated processing of lignocellulosic sugarcane biomass.
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Affiliation(s)
- Jae Yoon Kim
- Plant Molecular and Cellular Biology Program, Agronomy Department, Genetics Institute, University of Florida - IFAS, Gainesville, FL, USA
- Division of Biotechnology, Korea University, Seongbuk-Gu, Seoul, 02841, Republic of Korea
| | - Guang Nong
- Department of Microbiology and Cell Science, University of Florida - IFAS, Gainesville, FL, USA
| | - John D Rice
- Department of Microbiology and Cell Science, University of Florida - IFAS, Gainesville, FL, USA
| | - Maria Gallo
- Plant Molecular and Cellular Biology Program, Agronomy Department, Genetics Institute, University of Florida - IFAS, Gainesville, FL, USA
- Delaware Valley University, Doylestown, PA, USA
| | - James F Preston
- Department of Microbiology and Cell Science, University of Florida - IFAS, Gainesville, FL, USA
| | - Fredy Altpeter
- Plant Molecular and Cellular Biology Program, Agronomy Department, Genetics Institute, University of Florida - IFAS, Gainesville, FL, USA.
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Jung JH, Kannan B, Dermawan H, Moxley GW, Altpeter F. Precision breeding for RNAi suppression of a major 4-coumarate:coenzyme A ligase gene improves cell wall saccharification from field grown sugarcane. PLANT MOLECULAR BIOLOGY 2016; 92:505-517. [PMID: 27549390 DOI: 10.1007/s11103-016-0527-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 08/08/2016] [Indexed: 05/02/2023]
Abstract
Sugarcane (Saccharum spp. hybrids) is a major feedstock for commercial bioethanol production. The recent integration of conversion technologies that utilize lignocellulosic sugarcane residues as well as sucrose from stem internodes has elevated bioethanol yields. RNAi suppression of lignin biosynthetic enzymes is a successful strategy to improve the saccharification of lignocellulosic biomass. 4-coumarate:coenzyme A ligase (4CL) is a key enzyme in the biosynthesis of phenylpropanoid metabolites, such as lignin and flavonoids. Identifying a major 4CL involved in lignin biosynthesis among multiple isoforms with functional divergence is key to manipulate lignin biosynthesis. In this study, two full length 4CL genes (Sh4CL1 and Sh4CL2) were isolated and characterized in sugarcane. Phylogenetic, expression and RNA interference (RNAi) analysis confirmed that Sh4CL1 is a major lignin biosynthetic gene. An intragenic precision breeding strategy may facilitate the regulatory approval of the genetically improved events and was used for RNAi suppression of Sh4CL1. Both, the RNAi inducing cassette and the expression cassette for the mutated ALS selection marker consisted entirely of DNA sequences from sugarcane or the sexually compatible species Sorghum bicolor. Field grown sugarcane with intragenic RNAi suppression of Sh4CL1 resulted in reduction of the total lignin content by up to 16.5 % along with altered monolignol ratios without reduction in biomass yield. Mature, field grown, intragenic sugarcane events displayed 52-76 % improved saccharification efficiency of lignocellulosic biomass compared to wild type (WT) controls. This demonstrates for the first time that an intragenic approach can add significant value to lignocellulosic feedstocks for biofuel and biochemical production.
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Affiliation(s)
- Je Hyeong Jung
- Agronomy Department, IFAS, University of Florida, PO Box 110500, Gainesville, FL, 32611, USA
- Institute of Life Science and Natural Resources, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, South Korea
| | - Baskaran Kannan
- Agronomy Department, IFAS, University of Florida, PO Box 110500, Gainesville, FL, 32611, USA
| | - Hugo Dermawan
- Agronomy Department, IFAS, University of Florida, PO Box 110500, Gainesville, FL, 32611, USA
| | | | - Fredy Altpeter
- Agronomy Department, IFAS, University of Florida, PO Box 110500, Gainesville, FL, 32611, USA.
- Plant Molecular and Cellular Biology Program, IFAS, University of Florida, PO Box 110300, Gainesville, FL, 32611, USA.
- University of Florida Genetics Institute, PO Box 103610, Gainesville, FL, 32610, USA.
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Jung JH, Altpeter F. TALEN mediated targeted mutagenesis of the caffeic acid O-methyltransferase in highly polyploid sugarcane improves cell wall composition for production of bioethanol. PLANT MOLECULAR BIOLOGY 2016; 92:131-42. [PMID: 27306903 PMCID: PMC4999463 DOI: 10.1007/s11103-016-0499-y] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 05/30/2016] [Indexed: 05/18/2023]
Abstract
Sugarcane (Saccharum spp. hybrids) is a prime crop for commercial biofuel production. Advanced conversion technology utilizes both, sucrose accumulating in sugarcane stems as well as cell wall bound sugars for commercial ethanol production. Reduction of lignin content significantly improves the conversion of lignocellulosic biomass into ethanol. Conventional mutagenesis is not expected to confer reduction in lignin content in sugarcane due to its high polyploidy (x = 10-13) and functional redundancy among homo(eo)logs. Here we deploy transcription activator-like effector nuclease (TALEN) to induce mutations in a highly conserved region of the caffeic acid O-methyltransferase (COMT) of sugarcane. Capillary electrophoresis (CE) was validated by pyrosequencing as reliable and inexpensive high throughput method for identification and quantitative characterization of TALEN mediated mutations. Targeted COMT mutations were identified by CE in up to 74 % of the lines. In different events 8-99 % of the wild type COMT were converted to mutant COMT as revealed by pyrosequencing. Mutation frequencies among mutant lines were positively correlated to lignin reduction. Events with a mutation frequency of 99 % displayed a 29-32 % reduction of the lignin content compared to non-transgenic controls along with significantly reduced S subunit content and elevated hemicellulose content. CE analysis displayed similar peak patterns between primary COMT mutants and their vegetative progenies suggesting that TALEN mediated mutations were faithfully transmitted to vegetative progenies. This is the first report on genome editing in sugarcane. The findings demonstrate that targeted mutagenesis can improve cell wall characteristics for production of lignocellulosic ethanol in crops with highly complex genomes.
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Affiliation(s)
- Je Hyeong Jung
- Agronomy Department, University of Florida, IFAS, PO Box 110300, Gainesville, FL, 32611, USA
- Institute of Life Science and Natural Resources, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Fredy Altpeter
- Agronomy Department, University of Florida, IFAS, PO Box 110300, Gainesville, FL, 32611, USA.
- Plant Molecular and Cellular Biology Program, University of Florida, IFAS, PO Box 110300, Gainesville, FL, 32611, USA.
- Agronomy Department, University of Florida-IFAS, PO Box 103610, Gainesville, FL, 32611, USA.
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Martins MTB, de Souza WR, da Cunha BADB, Basso MF, de Oliveira NG, Vinecky F, Martins PK, de Oliveira PA, Arenque-Musa BC, de Souza AP, Buckeridge MS, Kobayashi AK, Quirino BF, Molinari HBC. Characterization of sugarcane (Saccharum spp.) leaf senescence: implications for biofuel production. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:153. [PMID: 27453728 PMCID: PMC4957918 DOI: 10.1186/s13068-016-0568-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 07/12/2016] [Indexed: 05/29/2023]
Abstract
BACKGROUND Second-generation ethanol (2G-bioethanol) uses lignocellulosic feedstocks for ethanol production. Sugarcane is one among the most suitable crops for biofuel production. Its juice is extracted for sugar production, while sugarcane bagasse, straw, and senescing leaves are considered industrial waste. Senescence is the age-dependent deterioration of plant cells, ultimately leading to cell death and completion of the plant life cycle. Because senescing leaves may also be used for biofuel production, understanding the process of natural senescence, including remobilization of nutrients and its effect on cell walls can provide useful information for 2G-bioethanol production from sugarcane leaves. RESULTS The natural senescence process in leaves of the commercial sugarcane cultivar RB867515 was investigated. Senescence was characterized by strong reduction in photosynthetic pigments content, remobilization of the nutrients N, P, K, B, Cu, Fe, and Zn, and accumulation of Ca, S, Mg, B, Mn, and Al. No significant changes in the cell-wall composition occurred, and only small changes in the expression of cell wall-related genes were observed, suggesting that cell walls are preserved during senescence. Senescence-marker genes, such as SAG12-like and XET-like genes, were also identified in sugarcane and found to be highly expressed. CONCLUSIONS Our study on nutrient remobilization under senescence in a vigorous sugarcane cultivar can contribute to the understanding on how nutrient balance in a high-yielding crop is achieved. In general, neutral monosaccharide profile did not change significantly with leaf senescence, suggesting that senescing leaves of sugarcane can be as a feedstock for biofuel production using pretreatments established for non-senescing leaves without additional efforts. Based on our findings, the potential biotechnological applications for the improvement of sugarcane cultivars are discussed.
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Affiliation(s)
- Maria Thereza Bazzo Martins
- />Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
- />Genomic Sciences and Biotechnology Program, Universidade Catolica de Brasilia, Brasília, DF 70790‑160 Brazil
| | - Wagner Rodrigo de Souza
- />Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | | | - Marcos Fernando Basso
- />Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | | | - Felipe Vinecky
- />Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | - Polyana Kelly Martins
- />Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | | | - Bruna Cersózimo Arenque-Musa
- />Laboratory of Plant Physiological Ecology (LAFIECO), Department of Botany-Institute of Biosciences, University of São Paulo, São Paulo, SP 05508-090 Brazil
| | - Amanda Pereira de Souza
- />Laboratory of Plant Physiological Ecology (LAFIECO), Department of Botany-Institute of Biosciences, University of São Paulo, São Paulo, SP 05508-090 Brazil
| | - Marcos Silveira Buckeridge
- />Laboratory of Plant Physiological Ecology (LAFIECO), Department of Botany-Institute of Biosciences, University of São Paulo, São Paulo, SP 05508-090 Brazil
| | - Adilson Kenji Kobayashi
- />Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | - Betania Ferraz Quirino
- />Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
- />Genomic Sciences and Biotechnology Program, Universidade Catolica de Brasilia, Brasília, DF 70790‑160 Brazil
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Poovaiah CR, Bewg WP, Lan W, Ralph J, Coleman HD. Sugarcane transgenics expressing MYB transcription factors show improved glucose release. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:143. [PMID: 27429646 PMCID: PMC4946106 DOI: 10.1186/s13068-016-0559-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/30/2016] [Indexed: 05/18/2023]
Abstract
BACKGROUND Sugarcane, a tropical C4 perennial crop, is capable of producing 30-100 tons or more of biomass per hectare annually. The lignocellulosic residue remaining after sugar extraction is currently underutilized and can provide a significant source of biomass for the production of second-generation bioethanol. RESULTS MYB31 and MYB42 were cloned from maize and expressed in sugarcane with and without the UTR sequences. The cloned sequences were 98 and 99 % identical to the published nucleotide sequences. The inclusion of the UTR sequences did not affect any of the parameters tested. There was little difference in plant height and the number of internodes of the MYB-overexpressing sugarcane plants when compared with controls. MYB transgene expression determined by qPCR exhibited continued expression in young and maturing internodes. MYB31 downregulated more genes within the lignin biosynthetic pathway than MYB42. MYB31 and MYB42 expression resulted in decreased lignin content in some lines. All MYB42 plants further analyzed showed significant increases in glucose release by enzymatic hydrolysis in 72 h, whereas only two MYB31 plants released more glucose than control plants. This correlated directly with a significant decrease in acid-insoluble lignin. Soluble sucrose content of the MYB42 transgenic plants did not vary compared to control plants. CONCLUSIONS This study demonstrates the use of MYB transcription factors to improve the production of bioethanol from sugarcane bagasse remaining after sugar extraction.
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Affiliation(s)
| | - William P. Bewg
- />Center for Tropical Crops and Biocommodities, Queensland University of Technology, Brisbane, QLD 4000 Australia
| | - Wu Lan
- />US Department of Energy, Great Lakes Bioenergy Research Center (GLBRC), Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726 USA
- />Department of Biological System Engineering, University of Wisconsin, Madison, WI USA
| | - John Ralph
- />US Department of Energy, Great Lakes Bioenergy Research Center (GLBRC), Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726 USA
- />Department of Biochemistry, University of Wisconsin, Madison, WI 53726 USA
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Enhancing digestibility and ethanol yield of Populus wood via expression of an engineered monolignol 4-O-methyltransferase. Nat Commun 2016; 7:11989. [PMID: 27349324 PMCID: PMC4931242 DOI: 10.1038/ncomms11989] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 05/18/2016] [Indexed: 11/16/2022] Open
Abstract
Producing cellulosic biofuels and bio-based chemicals from woody biomass is impeded by the presence of lignin polymer in the plant cell wall. Manipulating the monolignol biosynthetic pathway offers a promising approach to improved processability, but often impairs plant growth and development. Here, we show that expressing an engineered 4-O-methyltransferase that chemically modifies the phenolic moiety of lignin monomeric precursors, thus preventing their incorporation into the lignin polymer, substantially alters hybrid aspens' lignin content and structure. Woody biomass derived from the transgenic aspens shows a 62% increase in the release of simple sugars and up to a 49% increase in the yield of ethanol when the woody biomass is subjected to enzymatic digestion and yeast-mediated fermentation. Moreover, the cell wall structural changes do not affect growth and biomass production of the trees. Our study provides a useful strategy for tailoring woody biomass for bio-based applications. The efficiency of cellulosic biofuel production from woody biomass is limited by the presence of lignin that impedes efficient processing. Here the authors show that transgenic modification of aspen to depress lignin polymerization can increase ethanol yield without affecting tree growth.
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Wang Y, Fan C, Hu H, Li Y, Sun D, Wang Y, Peng L. Genetic modification of plant cell walls to enhance biomass yield and biofuel production in bioenergy crops. Biotechnol Adv 2016; 34:997-1017. [PMID: 27269671 DOI: 10.1016/j.biotechadv.2016.06.001] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 05/31/2016] [Accepted: 06/01/2016] [Indexed: 02/06/2023]
Abstract
Plant cell walls represent an enormous biomass resource for the generation of biofuels and chemicals. As lignocellulose property principally determines biomass recalcitrance, the genetic modification of plant cell walls has been posed as a powerful solution. Here, we review recent progress in understanding the effects of distinct cell wall polymers (cellulose, hemicelluloses, lignin, pectin, wall proteins) on the enzymatic digestibility of biomass under various physical and chemical pretreatments in herbaceous grasses, major agronomic crops and fast-growing trees. We also compare the main factors of wall polymer features, including cellulose crystallinity (CrI), hemicellulosic Xyl/Ara ratio, monolignol proportion and uronic acid level. Furthermore, the review presents the main gene candidates, such as CesA, GH9, GH10, GT61, GT43 etc., for potential genetic cell wall modification towards enhancing both biomass yield and enzymatic saccharification in genetic mutants and transgenic plants. Regarding cell wall modification, it proposes a novel groove-like cell wall model that highlights to increase amorphous regions (density and depth) of the native cellulose microfibrils, providing a general strategy for bioenergy crop breeding and biofuel processing technology.
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Affiliation(s)
- Yanting Wang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Chunfen Fan
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Huizhen Hu
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Ying Li
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Dan Sun
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; College of Chemistry and Chemical Engineering, Hubei University of Technology, Wuhan, Hubei 430068, China
| | - Youmei Wang
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Liangcai Peng
- Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
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Singh RK, Prasad M. Advances in Agrobacterium tumefaciens-mediated genetic transformation of graminaceous crops. PROTOPLASMA 2016; 253:691-707. [PMID: 26660352 DOI: 10.1007/s00709-015-0905-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 10/27/2015] [Indexed: 05/05/2023]
Abstract
Steady increase in global population poses several challenges to plant science research, including demand for increased crop productivity, grain yield, nutritional quality and improved tolerance to different environmental factors. Transgene-based approaches are promising to address these challenges by transferring potential candidate genes to host organisms through different strategies. Agrobacterium-mediated gene transfer is one such strategy which is well known for enabling efficient gene transfer in both monocot and dicots. Due to its versatility, this technique underwent several advancements including development of improved in vitro plant regeneration system, co-cultivation and selection methods, and use of hyper-virulent strains of Agrobacterium tumefaciens harbouring super-binary vectors. The efficiency of this method has also been enhanced by the use of acetosyringone to induce the activity of vir genes, silver nitrate to reduce the Agrobacterium-induced necrosis and cysteine to avoid callus browning during co-cultivation. In the last two decades, extensive efforts have been invested towards achieving efficient Agrobacterium-mediated transformation in cereals. Though high-efficiency transformation systems have been developed for rice and maize, comparatively lesser progress has been reported in other graminaceous crops. In this context, the present review discusses the progress made in Agrobacterium-mediated transformation system in rice, maize, wheat, barley, sorghum, sugarcane, Brachypodium, millets, bioenergy and forage and turf grasses. In addition, it also provides an overview of the genes that have been recently transferred to these graminaceous crops using Agrobacterium, bottlenecks in this technique and future possibilities for crop improvement.
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Affiliation(s)
- Roshan Kumar Singh
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, JNU Campus, New Delhi, 110 067, India
| | - Manoj Prasad
- National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, JNU Campus, New Delhi, 110 067, India.
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Torres AF, Slegers PM, Noordam-Boot CMM, Dolstra O, Vlaswinkel L, van Boxtel AJB, Visser RGF, Trindade LM. Maize feedstocks with improved digestibility reduce the costs and environmental impacts of biomass pretreatment and saccharification. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:63. [PMID: 26981155 PMCID: PMC4791978 DOI: 10.1186/s13068-016-0479-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 03/03/2016] [Indexed: 05/04/2023]
Abstract
BACKGROUND Despite the recognition that feedstock composition influences biomass conversion efficiency, limited information exists as to how bioenergy crops with reduced recalcitrance can improve the economics and sustainability of cellulosic fuel conversion platforms. We have compared the bioenergy potential-estimated as total glucose productivity per hectare (TGP)-of maize cultivars contrasting for cell wall digestibility across processing conditions of increasing thermochemical severity. In addition, exploratory environmental impact and economic modeling were used to assess whether the development of bioenergy feedstocks with improved cell wall digestibility can enhance the environmental performance and reduce the costs of biomass pretreatment and enzymatic conversion. RESULTS Systematic genetic gains in cell wall degradability can lead to significant advances in the productivity (TGP) of cellulosic fuel biorefineries under low severity processing; only if gains in digestibility are not accompanied by substantial yield penalties. For a hypothetical maize genotype combining the best characteristics available in the evaluated cultivar panel, TGP under mild processing conditions (~3.7 t ha(-1)) matched the highest realizable yields possible at the highest processing severity. Under this scenario, both, the environmental impacts and processing costs for the pretreatment and enzymatic saccharification of maize stover were reduced by 15 %, given lower chemical and heat consumption. CONCLUSIONS Genetic improvements in cell wall composition leading to superior cell wall digestibility can be advantageous for cellulosic fuel production, especially if "less severe" processing regimes are favored for further development. Exploratory results indicate potential cost and environmental impact reductions for the pretreatment and enzymatic saccharification of maize feedstocks exhibiting higher cell wall degradability. Conceptually, these results demonstrate that the advance of bioenergy cultivars with improved biomass degradability can enhance the performance of currently available biomass-to-ethanol conversion systems.
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Affiliation(s)
- Andres F. Torres
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
- />Plant Biotechnology Laboratory (COCIBA), Universidad San Francisco de Quito USFQ, Diego de Robles y Vía Interoceánica, Cumbayá, Ecuador
| | - Petronella M. Slegers
- />Biobased Chemistry and Technology, Wageningen University and Research Centre, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | | | - Oene Dolstra
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
| | | | - Anton J. B. van Boxtel
- />Biobased Chemistry and Technology, Wageningen University and Research Centre, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | - Richard G. F. Visser
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
| | - Luisa M. Trindade
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
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Bewg WP, Poovaiah C, Lan W, Ralph J, Coleman HD. RNAi downregulation of three key lignin genes in sugarcane improves glucose release without reduction in sugar production. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:270. [PMID: 28031745 PMCID: PMC5168864 DOI: 10.1186/s13068-016-0683-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/06/2016] [Indexed: 05/15/2023]
Abstract
BACKGROUND Sugarcane is a subtropical crop that produces large amounts of biomass annually. It is a key agricultural crop in many countries for the production of sugar and other products. Residual bagasse following sucrose extraction is currently underutilized and it has potential as a carbohydrate source for the production of biofuels. As with all lignocellulosic crops, lignin acts as a barrier to accessing the polysaccharides, and as such, is the focus of transgenic efforts. In this study, we used RNAi to individually reduce the expression of three key genes in the lignin biosynthetic pathway in sugarcane. These genes, caffeoyl-CoA O-methyltransferase (CCoAOMT), ferulate 5-hydroxylase (F5H) and caffeic acid O-methyltransferase (COMT), impact lignin content and/or composition. RESULTS For each RNAi construct, we selected three events for further analysis based on qRT-PCR results. For the CCoAOMT lines, there were no lines with a reduction in lignin content and only one line showed improved glucose release. For F5H, no lines had reduced lignin, but one line had a significant increase in glucose release. For COMT, one line had reduced lignin content, and this line and another released higher levels of glucose during enzymatic hydrolysis. Two of the lines with improved glucose release (F5H-2 and COMT-2) also had reduced S:G ratios. CONCLUSIONS Along with improvements in bagasse quality for the production of lignocellulosic-based fuels, there was only one line with reduction in juice sucrose extraction, and three lines with significantly improved sucrose production, providing evidence that the alteration of sugarcane for improved lignocellulosic ethanol production can be achieved without negatively impacting sugar production and perhaps even enhancing it.
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Affiliation(s)
- William P Bewg
- Queensland University of Technology, Brisbane, QLD 4000 Australia
| | | | - Wu Lan
- Department of Biological Systems Engineering, University of Wisconsin, Madison, WI USA ; US Department of Energy, Great Lakes Bioenergy Research Center (GLBRC), Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726 USA
| | - John Ralph
- US Department of Energy, Great Lakes Bioenergy Research Center (GLBRC), Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726 USA ; Department of Biochemistry, University of Wisconsin, Madison, WI 53726 USA
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Ho-Yue-Kuang S, Alvarado C, Antelme S, Bouchet B, Cézard L, Le Bris P, Legée F, Maia-Grondard A, Yoshinaga A, Saulnier L, Guillon F, Sibout R, Lapierre C, Chateigner-Boutin AL. Mutation in Brachypodium caffeic acid O-methyltransferase 6 alters stem and grain lignins and improves straw saccharification without deteriorating grain quality. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:227-37. [PMID: 26433202 PMCID: PMC4682429 DOI: 10.1093/jxb/erv446] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Cereal crop by-products are a promising source of renewable raw material for the production of biofuel from lignocellulose. However, their enzymatic conversion to fermentable sugars is detrimentally affected by lignins. Here the characterization of the Brachypodium Bd5139 mutant provided with a single nucleotide mutation in the caffeic acid O-methyltransferase BdCOMT6 gene is reported. This BdCOMT6-deficient mutant displayed a moderately altered lignification in mature stems. The lignin-related BdCOMT6 gene was also found to be expressed in grains, and the alterations of Bd5139 grain lignins were found to mirror nicely those evidenced in stem lignins. The Bd5139 grains displayed similar size and composition to the control. Complementation experiments carried out by introducing the mutated gene into the AtCOMT1-deficient Arabidopsis mutant demonstrated that the mutated BdCOMT6 protein was still functional. Such a moderate down-regulation of lignin-related COMT enzyme reduced the straw recalcitrance to saccharification, without compromising the vegetative or reproductive development of the plant.
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Affiliation(s)
- Séverine Ho-Yue-Kuang
- INRA-UR1268 Biopolymères, Interactions, Assemblages, F-44316 Nantes, France INRA-UMR1318, Institut Jean-Pierre Bourgin, F-78026 Versailles, France
| | - Camille Alvarado
- INRA-UR1268 Biopolymères, Interactions, Assemblages, F-44316 Nantes, France
| | - Sébastien Antelme
- INRA-UMR1318, Institut Jean-Pierre Bourgin, F-78026 Versailles, France
| | - Brigitte Bouchet
- INRA-UR1268 Biopolymères, Interactions, Assemblages, F-44316 Nantes, France
| | - Laurent Cézard
- INRA-UMR1318, Institut Jean-Pierre Bourgin, F-78026 Versailles, France
| | - Philippe Le Bris
- INRA-UMR1318, Institut Jean-Pierre Bourgin, F-78026 Versailles, France
| | - Frédéric Legée
- INRA-UMR1318, Institut Jean-Pierre Bourgin, F-78026 Versailles, France
| | | | - Arata Yoshinaga
- Laboratory of Tree Cell Biology, Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Luc Saulnier
- INRA-UR1268 Biopolymères, Interactions, Assemblages, F-44316 Nantes, France
| | - Fabienne Guillon
- INRA-UR1268 Biopolymères, Interactions, Assemblages, F-44316 Nantes, France
| | - Richard Sibout
- INRA-UMR1318, Institut Jean-Pierre Bourgin, F-78026 Versailles, France
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Kamei CLA, Severing EI, Dechesne A, Furrer H, Dolstra O, Trindade LM. Orphan Crops Browser: a bridge between model and orphan crops. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2016; 36:9. [PMID: 26798323 PMCID: PMC4710642 DOI: 10.1007/s11032-015-0430-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 12/23/2015] [Indexed: 05/20/2023]
Abstract
Many important crops have received little attention by the scientific community, either because they are not considered economically important or due to their large and complex genomes. De novo transcriptome assembly, using next-generation sequencing data, is an attractive option for the study of these orphan crops. In spite of the large amount of sequencing data that can be generated, there is currently a lack of tools which can effectively help molecular breeders and biologists to mine this type of information. Our goal was to develop a tool that enables molecular breeders, without extensive bioinformatics knowledge, to efficiently study de novo transcriptome data from any orphan crop (http://www.bioinformatics.nl/denovobrowser/db/species/index). The Orphan Crops Browser has been designed to facilitate the following tasks (1) search and identification of candidate transcripts based on phylogenetic relationships between orthologous sequence data from a set of related species and (2) design specific and degenerate primers for expression studies in the orphan crop of interest. To demonstrate the usability and reliability of the browser, it was used to identify the putative orthologues of 17 known lignin biosynthetic genes from maize and sugarcane in the orphan crop Miscanthus sinensis. Expression studies in miscanthus stem internode tissue differing in maturation were subsequently carried out, to follow the expression of these genes during lignification. Our results showed a negative correlation between lignin content and gene expression. The present data are in agreement with recent findings in maize and other crops, and it is further discussed in this paper.
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Affiliation(s)
- Claire Lessa Alvim Kamei
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
- />Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, 50829 Cologne, Germany
| | - Edouard I. Severing
- />Laboratory of Genetics, Wageningen University and Research Centre, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
- />Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, 50829 Cologne, Germany
| | - Annemarie Dechesne
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Heleen Furrer
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Oene Dolstra
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Luisa M. Trindade
- />Wageningen UR Plant Breeding, Wageningen University and Research Centre, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
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Vargas L, Cesarino I, Vanholme R, Voorend W, de Lyra Soriano Saleme M, Morreel K, Boerjan W. Improving total saccharification yield of Arabidopsis plants by vessel-specific complementation of caffeoyl shikimate esterase (cse) mutants. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:139. [PMID: 27390589 PMCID: PMC4936005 DOI: 10.1186/s13068-016-0551-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 06/23/2016] [Indexed: 05/02/2023]
Abstract
BACKGROUND Caffeoyl shikimate esterase (CSE) was recently characterized as an enzyme central to the lignin biosynthetic pathway in Arabidopsis thaliana. The cse-2 loss-of-function mutant shows a typical phenotype of lignin-deficient mutants, including collapsed vessels, reduced lignin content, and lignin compositional shift, in addition to a fourfold increase in cellulose-to-glucose conversion when compared to the wild type. However, this mutant exhibits a substantial developmental arrest, which might outweigh the gains in fermentable sugar yield. To restore its normal growth and further improve its saccharification yield, we investigated a possible cause for the yield penalty of the cse-2 mutant. Furthermore, we evaluated whether CSE expression is under the same multi-leveled transcriptional regulatory network as other lignin biosynthetic genes and analyzed the transcriptional responses of the phenylpropanoid pathway upon disruption of CSE. RESULTS Transactivation analysis demonstrated that only second-level MYB master switches (MYB46 and MYB83) and lignin-specific activators (MYB63 and MYB85), but not top-level NAC master switches or other downstream transcription factors, effectively activate the CSE promoter in our protoplast-based system. The cse-2 mutant exhibited transcriptional repression of genes upstream of CSE, while downstream genes were mainly unaffected, indicating transcriptional feedback of CSE loss-of-function on monolignol biosynthetic genes. In addition, we found that the expression of CSE under the control of the vessel-specific VND7 promoter in the cse-2 background restored the vasculature integrity resulting in improved growth parameters, while the overall lignin content remained relatively low. Thus, by restoring the vascular integrity and biomass parameters of cse-2, we further improved glucose release per plant without pretreatment, with an increase of up to 36 % compared to the cse-2 mutant and up to 154 % compared to the wild type. CONCLUSIONS Our results contribute to a better understanding of how the expression of CSE is regulated by secondary wall-associated transcription factors and how the expression of lignin genes is affected upon CSE loss-of-function in Arabidopsis. Moreover, we found evidence that vasculature collapse is underlying the yield penalty found in the cse-2 mutant. Through a vessel-specific complementation approach, vasculature morphology and final stem weight were restored, leading to an even higher total glucose release per plant.
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Affiliation(s)
- Lívia Vargas
- />Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- />Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Igor Cesarino
- />Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- />Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- />Department of Botany, Institute of Biosciences, University of São Paulo, Butantã, SP Brazil
| | - Ruben Vanholme
- />Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- />Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Wannes Voorend
- />Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- />Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Marina de Lyra Soriano Saleme
- />Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- />Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Kris Morreel
- />Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- />Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Wout Boerjan
- />Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- />Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
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Hoang NV, Furtado A, Botha FC, Simmons BA, Henry RJ. Potential for Genetic Improvement of Sugarcane as a Source of Biomass for Biofuels. Front Bioeng Biotechnol 2015; 3:182. [PMID: 26636072 PMCID: PMC4646955 DOI: 10.3389/fbioe.2015.00182] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 10/26/2015] [Indexed: 11/13/2022] Open
Abstract
Sugarcane (Saccharum spp. hybrids) has great potential as a major feedstock for biofuel production worldwide. It is considered among the best options for producing biofuels today due to an exceptional biomass production capacity, high carbohydrate (sugar + fiber) content, and a favorable energy input/output ratio. To maximize the conversion of sugarcane biomass into biofuels, it is imperative to generate improved sugarcane varieties with better biomass degradability. However, unlike many diploid plants, where genetic tools are well developed, biotechnological improvement is hindered in sugarcane by our current limited understanding of the large and complex genome. Therefore, understanding the genetics of the key biofuel traits in sugarcane and optimization of sugarcane biomass composition will advance efficient conversion of sugarcane biomass into fermentable sugars for biofuel production. The large existing phenotypic variation in Saccharum germplasm and the availability of the current genomics technologies will allow biofuel traits to be characterized, the genetic basis of critical differences in biomass composition to be determined, and targets for improvement of sugarcane for biofuels to be established. Emerging options for genetic improvement of sugarcane for the use as a bioenergy crop are reviewed. This will better define the targets for potential genetic manipulation of sugarcane biomass composition for biofuels.
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Affiliation(s)
- Nam V. Hoang
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, Australia
- College of Agriculture and Forestry, Hue University, Hue, Vietnam
| | - Agnelo Furtado
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, Australia
| | - Frederik C. Botha
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, Australia
- Sugar Research Australia, Indooroopilly, QLD, Australia
| | - Blake A. Simmons
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, Australia
- Joint BioEnergy Institute, Emeryville, CA, USA
| | - Robert J. Henry
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, Australia
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