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Funnell-Harris DL, Sattler SE, O'Neill PM, Gries T, Ge Z, Nersesian N. Effects of Altering Three Steps of Monolignol Biosynthesis on Sorghum Responses to Stalk Pathogens and Water Deficit. PLANT DISEASE 2023; 107:3984-3995. [PMID: 37430480 DOI: 10.1094/pdis-08-22-1959-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
The drought-resilient crop sorghum (Sorghum bicolor [L.] Moench) is grown worldwide for multiple uses, including forage or potential lignocellulosic bioenergy feedstock. A major impediment to biomass yield and quality are the pathogens Fusarium thapsinum and Macrophomina phaseolina, which cause Fusarium stalk rot and charcoal rot, respectively. These fungi are more virulent with abiotic stresses such as drought. Monolignol biosynthesis plays a critical role in plant defense. The genes Brown midrib (Bmr)6, Bmr12, and Bmr2 encode the monolignol biosynthesis enzymes cinnamyl alcohol dehydrogenase, caffeic acid O-methyltransferase, and 4-coumarate:CoA ligase, respectively. Plant stalks from lines overexpressing these genes and containing bmr mutations were screened for pathogen responses with controlled adequate or deficit watering. Additionally, near-isogenic bmr12 and wild-type lines in five backgrounds were screened for response to F. thapsinum with adequate and deficit watering. All mutant and overexpression lines were no more susceptible than corresponding wild-type under both watering conditions. The bmr2 and bmr12 lines, near-isogenic to wild-type, had significantly shorter mean lesion lengths (were more resistant) than RTx430 wild-type when inoculated with F. thapsinum under water deficit. Additionally, bmr2 plants grown under water deficit had significantly smaller mean lesions when inoculated with M. phaseolina than under adequate-water conditions. When well-watered, bmr12 in cultivar Wheatland and one of two Bmr2 overexpression lines in RTx430 had shorter mean lesion lengths than corresponding wild-type lines. This research demonstrates that modifying monolignol biosynthesis for increased usability may not impair plant defenses but can even enhance resistance to stalk pathogens under drought conditions.
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Affiliation(s)
- Deanna L Funnell-Harris
- Wheat, Sorghum, and Forage Research Unit, United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Plant Pathology, University of Nebraska, Lincoln (UNL), Lincoln, NE 68583
| | - Scott E Sattler
- Wheat, Sorghum, and Forage Research Unit, United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Agronomy and Horticulture, UNL, Lincoln, NE 68583
| | - Patrick M O'Neill
- Wheat, Sorghum, and Forage Research Unit, United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Plant Pathology, University of Nebraska, Lincoln (UNL), Lincoln, NE 68583
| | - Tammy Gries
- Wheat, Sorghum, and Forage Research Unit, United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Agronomy and Horticulture, UNL, Lincoln, NE 68583
| | - Zhengxiang Ge
- Department of Agronomy and Horticulture, UNL, Lincoln, NE 68583
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Lewis JA, Zhang B, Harza R, Palmer N, Sarath G, Sattler SE, Twigg P, Vermerris W, Kang C. Structural Similarities and Overlapping Activities among Dihydroflavonol 4-Reductase, Flavanone 4-Reductase, and Anthocyanidin Reductase Offer Metabolic Flexibility in the Flavonoid Pathway. Int J Mol Sci 2023; 24:13901. [PMID: 37762209 PMCID: PMC10531346 DOI: 10.3390/ijms241813901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 08/31/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Flavonoids are potent antioxidants that play a role in defense against pathogens, UV-radiation, and the detoxification of reactive oxygen species. Dihydroflavonol 4-reductase (DFR) and flavanone 4-reductase (FNR) reduce dihydroflavonols and flavanones, respectively, using NAD(P)H to produce flavan-(3)-4-(di)ols in flavonoid biosynthesis. Anthocyanidin reductase (ANR) reduces anthocyanidins to flavan-3-ols. In addition to their sequences, the 3D structures of recombinant DFR, FNR and ANR from sorghum and switchgrass showed a high level of similarity. The catalytic mechanism, substrate-specificity and key residues of three reductases were deduced from crystal structures, site-directed mutagenesis, molecular docking, kinetics, and thermodynamic ana-lyses. Although DFR displayed its highest activity against dihydroflavonols, it also showed activity against flavanones and anthocyanidins. It was inhibited by the flavonol quercetin and high concentrations of dihydroflavonols/flavonones. SbFNR1 and SbFNR2 did not show any activity against dihydroflavonols. However, SbFNR1 displayed activity against flavanones and ANR activity against two anthocyanidins, cyanidin and pelargonidin. Therefore, SbFNR1 and SbFNR2 could be specific ANR isozymes without delphinidin activity. Sorghum has high concentrations of 3-deoxyanthocyanidins in vivo, supporting the observed high activity of SbDFR against flavonols. Mining of expression data indicated substantial induction of these three reductase genes in both switchgrass and sorghum in response to biotic stress. Key signature sequences for proper DFR/ANR classification are proposed and could form the basis for future metabolic engineering of flavonoid metabolism.
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Affiliation(s)
- Jacob A. Lewis
- Department of Chemistry, Washington State University, Pullman, WA 99164, USA; (J.A.L.); (B.Z.)
| | - Bixia Zhang
- Department of Chemistry, Washington State University, Pullman, WA 99164, USA; (J.A.L.); (B.Z.)
| | - Rishi Harza
- Department of Chemistry, Washington State University, Pullman, WA 99164, USA; (J.A.L.); (B.Z.)
| | - Nathan Palmer
- Wheat, Sorghum, Forage Research Unit, U.S. Department of Agriculture—Agricultural Research Service, Lincoln, NE 68583, USA; (N.P.); (G.S.); (S.E.S.)
| | - Gautam Sarath
- Wheat, Sorghum, Forage Research Unit, U.S. Department of Agriculture—Agricultural Research Service, Lincoln, NE 68583, USA; (N.P.); (G.S.); (S.E.S.)
| | - Scott E. Sattler
- Wheat, Sorghum, Forage Research Unit, U.S. Department of Agriculture—Agricultural Research Service, Lincoln, NE 68583, USA; (N.P.); (G.S.); (S.E.S.)
| | - Paul Twigg
- Biology Department, University of Nebraska at Kearney, Kearney, NE 68849, USA;
| | - Wilfred Vermerris
- Department of Microbiology & Cell Science and UF Genetics Institute, University of Florida, Gainesville, FL 32610, USA;
| | - ChulHee Kang
- Department of Chemistry, Washington State University, Pullman, WA 99164, USA; (J.A.L.); (B.Z.)
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Transcriptional Comparison of New Hybrid Progenies and Clone-Cultivars of Tea (Camellia sinensis L.) Associated to Catechins Content. PLANTS 2022; 11:plants11151972. [PMID: 35956452 PMCID: PMC9370121 DOI: 10.3390/plants11151972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/17/2022] [Accepted: 07/20/2022] [Indexed: 11/22/2022]
Abstract
Heterosis or hybrid vigor is the improved performance of a desirable quality in hybrid progeny. Hybridization between high-productive Assam type and high-quality Chinese type clone-cultivar is expected to develop elite tea plant progenies with high quality and productivity. Comparative transcriptomics analyses of leaves from the F1 hybrids and their parental clone-cultivars were conducted to explore molecular mechanisms related to catechin content using a high-throughput next-generation RNA-seq strategy and high-performance liquid chromatography (HPLC). The content of EGCG (epigallocatechin gallate) and C (catechin) was higher in ‘Kiara-8’ × ‘Sukoi’, ‘Tambi-2’ × ‘Suka Ati’, and ‘Tambi-2’ × ‘TRI-2025’ than the other hybrid and clone-cultivars. KEGG (Kyoto Encyclopedia of Genes and Genomes) and GO (Gene Ontology) analysis found that most pathways associated with catechins content were enriched. Significant differentially expressed genes (DEGs) mainly associated with phenylpropanoid, flavonoid, drug metabolism-cytochrome P450, and transcription factor (MYB, bHLH, LOB, and C2H2) pathways appeared to be responsible for the high accumulation of secondary metabolites in ‘Kiara-8’ × ‘Sukoi’, ‘Tambi-2’ × ‘Suka Ati’, and ‘Tambi-2’ × ‘TRI-2025’ as were detected in EGCG and catechin content. Several structural genes related to the above pathways have been obtained, which will be used as candidate genes in the screening of breeding materials.
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Tan Y, Yang J, Jiang Y, Sun S, Wei X, Wang R, Bu J, Li D, Kang L, Chen T, Guo J, Cui G, Tang J, Huang L. Identification and characterization of two Isatis indigotica O-methyltransferases methylating C-glycosylflavonoids. HORTICULTURE RESEARCH 2022; 9:uhac140. [PMID: 36072835 PMCID: PMC9437721 DOI: 10.1093/hr/uhac140] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Isatis indigotica accumulates several active substances, including C-glycosylflavonoids, which have important pharmacological activities and health benefits. However, enzymes catalyzing the methylation step of C-glycosylflavonoids in I. indigotica remain unknown. In this study, three O-methyltransferases (OMTs) were identified from I. indigotica that have the capacity for O-methylation of the C-glycosylflavonoid isoorientin. The Type II OMTs IiOMT1 and IiOMT2 efficiently catalyze isoorientin to form isoscoparin, and decorate one of the aromatic vicinal hydroxyl groups on flavones and methylate the C6, C8, and 3'-hydroxyl positions to form oroxylin A, wogonin, and chrysoeriol, respectively. However, the Type I OMT IiOMT3 exhibited broader substrate promiscuity and methylated the C7 and 3'-hydroxyl positions of flavonoids. Further site-directed mutagenesis studies demonstrated that five amino acids of IiOMT1/IiOMT2 (D121/D100, D173/D149, A174/A150R, N200/N176, and D248/D233) were critical residues for their catalytic activity. Additionally, only transient overexpression of Type II OMTs IiOMT1 and IiOMT2 in Nicotiana benthamiana significantly increased isoscoparin accumulation, indicating that the Type II OMTs IiOMT1 and IiOMT2 could catalyze the methylation step of C-glycosylflavonoid, isoorientin at the 3'-hydroxyl position. This study provides insights into the biosynthesis of methylated C-glycosylflavonoids, and IiOMTs could be promising catalysts in the synthesis of bioactive compounds.
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Affiliation(s)
- Yuping Tan
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
- School of Traditional Chinese Medicine, Shenyang Pharmaceutical University, Shenyang 117004, China
| | - Jian Yang
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Yinyin Jiang
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Shufu Sun
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei 230012, China
| | - Xiaoyan Wei
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
- College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun 130118, China
| | - Ruishan Wang
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Junling Bu
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Dayong Li
- National Engineering Research Center for Vegetables, Beijing Vegetable Research Center, Beijing Academy of Agriculture and Forestry Science, Beijing 100097, China
| | - Liping Kang
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Tong Chen
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Juan Guo
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Guanghong Cui
- State Key Laboratory of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
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Zhao X, Niu Y, Bai X, Mao T. Transcriptomic and Metabolic Profiling Reveals a Lignin Metabolism Network Involved in Mesocotyl Elongation during Maize Seed Germination. PLANTS 2022; 11:plants11081034. [PMID: 35448762 PMCID: PMC9027596 DOI: 10.3390/plants11081034] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 11/18/2022]
Abstract
Lignin is an important factor affecting agricultural traits. The mechanism of lignin metabolism in maize (Zea mays) mesocotyl elongation was investigated during seed germination. Maize seeds were treated with 24-epibrassinolide (EBR) and brassinazole stimulation under 3 and 20 cm deep-seeding stress. Mesocotyl transcriptome sequencing together with targeted metabolomics analysis and physiological measurements were employed in two contrasting genotypes. Our results revealed differentially expressed genes (DEGs) were significantly enriched in phenylpropanoid biosynthesis, plant hormone signal transduction, flavonoid biosynthesis, and alpha-linolenic acid metabolism. There were 153 DEGs for lignin biosynthesis pathway, 70 DEGs for peroxisome pathway, and 325 differentially expressed transcription factors (TFs) of MYB, NAC, WRKY, and LIM were identified in all comparisons, and highly interconnected network maps were generated among multiple TFs (MYB and WRKY) and DEGs for lignin biosynthesis and peroxisome biogenesis. This caused p-coumaraldehyde, p-coumaryl alcohol, and sinapaldehyde down-accumulation,
however, caffeyl aldehyde and caffeyl alcohol up-accumulation. The sum/ratios of H-, S-, and G-lignin monomers was also altered, which decreased total lignin formation and accumulation, resulting in cell wall rigidity decreasing. As a result, a significant elongation of maize mesocotyl was detected under deep-seeding stress and EBR signaling. These findings provide information on the molecular mechanisms controlling maize seedling emergence under deep-seeding stress and will aid in the breeding of deep-seeding maize cultivars.
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Affiliation(s)
- Xiaoqiang Zhao
- Correspondence: (X.Z.); (Y.N.); Tel.: +86-183-9415-8662 (X.Z.); +86-139-1913-0638 (Y.N.)
| | - Yining Niu
- Correspondence: (X.Z.); (Y.N.); Tel.: +86-183-9415-8662 (X.Z.); +86-139-1913-0638 (Y.N.)
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Zhang B, Munske GR, Timokhin VI, Ralph J, Davydov DR, Vermerris W, Sattler SE, Kang C. Functional and structural insight into the flexibility of cytochrome P450 reductases from Sorghum bicolor and its implications for lignin composition. J Biol Chem 2022; 298:101761. [PMID: 35202651 PMCID: PMC8942828 DOI: 10.1016/j.jbc.2022.101761] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 11/17/2022] Open
Abstract
Plant NADPH-dependent cytochrome P450 reductase (CPR) is a multidomain enzyme that donates electrons for hydroxylation reactions catalyzed by class II cytochrome P450 monooxygenases involved in the synthesis of many primary and secondary metabolites. These P450 enzymes include trans-cinnamate-4-hydroxylase, p-coumarate-3′-hydroxylase, and ferulate-5-hydroxylase involved in monolignol biosynthesis. Because of its role in monolignol biosynthesis, alterations in CPR activity could change the composition and overall output of lignin. Therefore, to understand the structure and function of three CPR subunits from sorghum, recombinant subunits SbCPR2a, SbCPR2b, and SbCPR2c were subjected to X-ray crystallography and kinetic assays. Steady-state kinetic analyses demonstrated that all three CPR subunits supported the oxidation reactions catalyzed by SbC4H1 (CYP73A33) and SbC3′H (CYP98A1). Furthermore, comparing the SbCPR2b structure with the well-investigated CPRs from mammals enabled us to identify critical residues of functional importance and suggested that the plant flavin mononucleotide–binding domain might be more flexible than mammalian homologs. In addition, the elucidated structure of SbCPR2b included the first observation of NADP+ in a native CPR. Overall, we conclude that the connecting domain of SbCPR2, especially its hinge region, could serve as a target to alter biomass composition in bioenergy and forage sorghums through protein engineering.
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Affiliation(s)
- Bixia Zhang
- Department of Chemistry, Washington State University, Pullman, Washington, USA
| | - Gerhard R Munske
- School of Molecular Biosciences, Washington State University, Pullman, Washington, USA
| | - Vitaliy I Timokhin
- Department of Biochemistry and Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, Wisconsin, USA
| | - John Ralph
- Department of Biochemistry and Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, Wisconsin, USA
| | - Dmitri R Davydov
- Department of Chemistry, Washington State University, Pullman, Washington, USA
| | - Wilfred Vermerris
- Department of Microbiology & Cell Science and UF Genetics Institute, University of Florida, Gainesville, Florida, USA
| | - Scott E Sattler
- U.S. Department of Agriculture - Agricultural Research Service, Wheat, Sorghum and Forage Research Unit, Lincoln, Nebraska, USA
| | - ChulHee Kang
- Department of Chemistry, Washington State University, Pullman, Washington, USA.
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Tian Y, Lin CY, Park JH, Wu CY, Kakumanu R, Pidatala VR, Vuu KM, Rodriguez A, Shih PM, Baidoo EEK, Temple S, Simmons BA, Gladden JM, Scheller HV, Eudes A. Overexpression of the rice BAHD acyltransferase AT10 increases xylan-bound p-coumarate and reduces lignin in Sorghum bicolor. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:217. [PMID: 34801067 PMCID: PMC8606057 DOI: 10.1186/s13068-021-02068-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/06/2021] [Indexed: 05/14/2023]
Abstract
BACKGROUND The development of bioenergy crops with reduced recalcitrance to enzymatic degradation represents an important challenge to enable the sustainable production of advanced biofuels and bioproducts. Biomass recalcitrance is partly attributed to the complex structure of plant cell walls inside which cellulose microfibrils are protected by a network of hemicellulosic xylan chains that crosslink with each other or with lignin via ferulate (FA) bridges. Overexpression of the rice acyltransferase OsAT10 is an effective bioengineering strategy to lower the amount of FA involved in the formation of cell wall crosslinks and thereby reduce cell wall recalcitrance. The annual crop sorghum represents an attractive feedstock for bioenergy purposes considering its high biomass yields and low input requirements. Although we previously validated the OsAT10 engineering approach in the perennial bioenergy crop switchgrass, the effect of OsAT10 expression on biomass composition and digestibility in sorghum remains to be explored. RESULTS We obtained eight independent sorghum (Sorghum bicolor (L.) Moench) transgenic lines with a single copy of a construct designed for OsAT10 expression. Consistent with the proposed role of OsAT10 in acylating arabinosyl residues on xylan with p-coumarate (pCA), a higher amount of p-coumaroyl-arabinose was released from the cell walls of these lines upon hydrolysis with trifluoroacetic acid. However, no major changes were observed regarding the total amount of pCA or FA esters released from cell walls upon mild alkaline hydrolysis. Certain diferulate (diFA) isomers identified in alkaline hydrolysates were increased in some transgenic lines. The amount of the main cell wall monosaccharides glucose, xylose, and arabinose was unaffected. The transgenic lines showed reduced lignin content and their biomass released higher yields of sugars after ionic liquid pretreatment followed by enzymatic saccharification. CONCLUSIONS Expression of OsAT10 in sorghum leads to an increase of xylan-bound pCA without reducing the overall content of cell wall FA esters. Nevertheless, the amount of total cell wall pCA remains unchanged indicating that most pCA is ester-linked to lignin. Unlike other engineered plants overexpressing OsAT10 or a phylogenetically related acyltransferase with similar putative function, the improvements of biomass saccharification efficiency in sorghum OsAT10 lines are likely the result of lignin reductions rather than reductions of cell wall-bound FA. These results also suggest a relationship between xylan-bound pCA and lignification in cell walls.
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Affiliation(s)
- Yang Tian
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Chien-Yuan Lin
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | | | - Chuan-Yin Wu
- Forage Genetics International, West Salem, WI 54669 USA
| | - Ramu Kakumanu
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Venkataramana R. Pidatala
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Khanh M. Vuu
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Alberto Rodriguez
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Department of Biomaterials and Biomanufacturing, Sandia National Laboratories, Livermore, CA 94551 USA
| | - Patrick M. Shih
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
- Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720 USA
| | - Edward E. K. Baidoo
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | | | - Blake A. Simmons
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - John M. Gladden
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Department of Biomaterials and Biomanufacturing, Sandia National Laboratories, Livermore, CA 94551 USA
| | - Henrik V. Scheller
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
- Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720 USA
| | - Aymerick Eudes
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
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Khasin M, Bernhardson LF, O'Neill PM, Palmer NA, Scully ED, Sattler SE, Funnell-Harris DL. Pathogen and drought stress affect cell wall and phytohormone signaling to shape host responses in a sorghum COMT bmr12 mutant. BMC PLANT BIOLOGY 2021; 21:391. [PMID: 34418969 PMCID: PMC8379876 DOI: 10.1186/s12870-021-03149-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND As effects of global climate change intensify, the interaction of biotic and abiotic stresses increasingly threatens current agricultural practices. The secondary cell wall is a vanguard of resistance to these stresses. Fusarium thapsinum (Fusarium stalk rot) and Macrophomina phaseolina (charcoal rot) cause internal damage to the stalks of the drought tolerant C4 grass, sorghum (Sorghum bicolor (L.) Moench), resulting in reduced transpiration, reduced photosynthesis, and increased lodging, severely reducing yields. Drought can magnify these losses. Two null alleles in monolignol biosynthesis of sorghum (brown midrib 6-ref, bmr6-ref; cinnamyl alcohol dehydrogenase, CAD; and bmr12-ref; caffeic acid O-methyltransferase, COMT) were used to investigate the interaction of water limitation with F. thapsinum or M. phaseolina infection. RESULTS The bmr12 plants inoculated with either of these pathogens had increased levels of salicylic acid (SA) and jasmonic acid (JA) across both watering conditions and significantly reduced lesion sizes under water limitation compared to adequate watering, which suggested that drought may prime induction of pathogen resistance. RNA-Seq analysis revealed coexpressed genes associated with pathogen infection. The defense response included phytohormone signal transduction pathways, primary and secondary cell wall biosynthetic genes, and genes encoding components of the spliceosome and proteasome. CONCLUSION Alterations in the composition of the secondary cell wall affect immunity by influencing phenolic composition and phytohormone signaling, leading to the action of defense pathways. Some of these pathways appear to be activated or enhanced by drought. Secondary metabolite biosynthesis and modification in SA and JA signal transduction may be involved in priming a stronger defense response in water-limited bmr12 plants.
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Affiliation(s)
- Maya Khasin
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, 251 Filley Hall, University of Nebraska-East Campus, Lincoln, NE, 68583, USA
- Department of Plant Pathology, University of Nebraska, Lincoln, NE, 68583, USA
| | - Lois F Bernhardson
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, 251 Filley Hall, University of Nebraska-East Campus, Lincoln, NE, 68583, USA
- Department of Plant Pathology, University of Nebraska, Lincoln, NE, 68583, USA
| | - Patrick M O'Neill
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, 251 Filley Hall, University of Nebraska-East Campus, Lincoln, NE, 68583, USA
- Department of Plant Pathology, University of Nebraska, Lincoln, NE, 68583, USA
| | - Nathan A Palmer
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, 251 Filley Hall, University of Nebraska-East Campus, Lincoln, NE, 68583, USA
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE, 68583, USA
| | - Erin D Scully
- Stored Product Insect and Engineering Research Unit, Center for Grain and Animal Health, USDA-ARS, Manhattan, KS, 66502, USA
- Department of Entomology, Kansas State University, Manhattan, KS, 66502, USA
| | - Scott E Sattler
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, 251 Filley Hall, University of Nebraska-East Campus, Lincoln, NE, 68583, USA
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE, 68583, USA
| | - Deanna L Funnell-Harris
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, 251 Filley Hall, University of Nebraska-East Campus, Lincoln, NE, 68583, USA.
- Department of Plant Pathology, University of Nebraska, Lincoln, NE, 68583, USA.
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Zhou C, Wang S, Zhou H, Yuan Z, Zhou T, Zhang Y, Xiang S, Yang F, Shen X, Zhang D. Transcriptome sequencing analysis of sorghum callus with various regeneration capacities. PLANTA 2021; 254:33. [PMID: 34287698 DOI: 10.1007/s00425-021-03683-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
The possible molecular mechanisms regulating sorghum callus regeneration were revealed by RNA-sequencing. Plant callus regeneration has been widely applied in agricultural improvement. Recently, callus regeneration has been successfully applied in the genetic transformation of sorghum by using immature sorghum embryos as explants. However, the mechanism underlying callus regeneration in sorghum is still largely unknown. Here, we describe three types of callus (Callus I-III) with different redifferentiation abilities undergoing distinct induction from immature embryos of the Hiro-1 variety. Compared with nonembryonic Callus III, Callus I produced only some identifiable roots, and embryonic Callus II was sufficient to regenerate whole plants. Genome-wide transcriptome profiles were generated to reveal the underlying mechanisms. The numbers of differentially expressed genes for the three types of callus varied from 5906 to 8029. In accordance with the diverse regeneration abilities observed for different types of callus and leaf tissues, the principal component analysis revealed that the gene expression patterns of Callus I and Callus II were different from those of Callus III and leaves regenerated from Callus II. Notably, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses, pharmacological treatment, and substance content determinations revealed that plant ribosomes, lignin metabolic processes, and metabolism of starch and sucrose were significantly enriched, suggesting that these factors are associated with callus regeneration. These results helped elucidate the molecular regulation of three types of callus with different regeneration abilities in sorghum.
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Affiliation(s)
- Chao Zhou
- Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement (CTGU)/Biotechnology Research Center, Yichang Key Laboratory of Omics-Based Breeding for Chinese Medicines, China Three Gorges University, Yichang, 443002, China
| | - Sijia Wang
- Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement (CTGU)/Biotechnology Research Center, Yichang Key Laboratory of Omics-Based Breeding for Chinese Medicines, China Three Gorges University, Yichang, 443002, China
| | - Hanlin Zhou
- Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement (CTGU)/Biotechnology Research Center, Yichang Key Laboratory of Omics-Based Breeding for Chinese Medicines, China Three Gorges University, Yichang, 443002, China
| | - Zhu Yuan
- Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement (CTGU)/Biotechnology Research Center, Yichang Key Laboratory of Omics-Based Breeding for Chinese Medicines, China Three Gorges University, Yichang, 443002, China
| | - Tao Zhou
- Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement (CTGU)/Biotechnology Research Center, Yichang Key Laboratory of Omics-Based Breeding for Chinese Medicines, China Three Gorges University, Yichang, 443002, China
| | - Yonghong Zhang
- Hubei Key Laboratory of Wudang Local Chinese Medicine Research, Hubei University of Medicine, Shiyan, 442000, China
| | - Sen Xiang
- School of Information Science and Engineering, Wuhan University of Science and Technology, Wuhan, 430081, China
| | - Fang Yang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, People's Republic of China
| | - Xiangling Shen
- Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement (CTGU)/Biotechnology Research Center, Yichang Key Laboratory of Omics-Based Breeding for Chinese Medicines, China Three Gorges University, Yichang, 443002, China
| | - Dechun Zhang
- Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement (CTGU)/Biotechnology Research Center, Yichang Key Laboratory of Omics-Based Breeding for Chinese Medicines, China Three Gorges University, Yichang, 443002, China.
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10
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Pingault L, Palmer NA, Koch KG, Heng-Moss T, Bradshaw JD, Seravalli J, Twigg P, Louis J, Sarath G. Differential Defense Responses of Upland and Lowland Switchgrass Cultivars to a Cereal Aphid Pest. Int J Mol Sci 2020; 21:ijms21217966. [PMID: 33120946 PMCID: PMC7672581 DOI: 10.3390/ijms21217966] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/22/2020] [Accepted: 10/24/2020] [Indexed: 02/01/2023] Open
Abstract
Yellow sugarcane aphid (YSA) (Sipha flava, Forbes) is a damaging pest on many grasses. Switchgrass (Panicum virgatum L.), a perennial C4 grass, has been selected as a bioenergy feedstock because of its perceived resilience to abiotic and biotic stresses. Aphid infestation on switchgrass has the potential to reduce the yields and biomass quantity. Here, the global defense response of switchgrass cultivars Summer and Kanlow to YSA feeding was analyzed by RNA-seq and metabolite analysis at 5, 10, and 15 days after infestation. Genes upregulated by infestation were more common in both cultivars compared to downregulated genes. In total, a higher number of differentially expressed genes (DEGs) were found in the YSA susceptible cultivar (Summer), and fewer DEGs were observed in the YSA resistant cultivar (Kanlow). Interestingly, no downregulated genes were found in common between each time point or between the two switchgrass cultivars. Gene co-expression analysis revealed upregulated genes in Kanlow were associated with functions such as flavonoid, oxidation-response to chemical, or wax composition. Downregulated genes for the cultivar Summer were found in co-expression modules with gene functions related to plant defense mechanisms or cell wall composition. Global analysis of defense networks of the two cultivars uncovered differential mechanisms associated with resistance or susceptibility of switchgrass in response to YSA infestation. Several gene co-expression modules and transcription factors correlated with these differential defense responses. Overall, the YSA-resistant Kanlow plants have an enhanced defense even under aphid uninfested conditions.
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Affiliation(s)
- Lise Pingault
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; (L.P.); (K.G.K.); (T.H.-M.); (J.D.B.)
| | - Nathan A. Palmer
- Wheat, Sorghum, and Forage Research Unit, USDA-ARS, Lincoln, NE 68583, USA;
| | - Kyle G. Koch
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; (L.P.); (K.G.K.); (T.H.-M.); (J.D.B.)
| | - Tiffany Heng-Moss
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; (L.P.); (K.G.K.); (T.H.-M.); (J.D.B.)
| | - Jeffrey D. Bradshaw
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; (L.P.); (K.G.K.); (T.H.-M.); (J.D.B.)
| | - Javier Seravalli
- Redox Biology Center, Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE 68588, USA;
| | - Paul Twigg
- Biology Department, University of Nebraska-Kearney, Kearney, NE 68849, USA;
| | - Joe Louis
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; (L.P.); (K.G.K.); (T.H.-M.); (J.D.B.)
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE 68583, USA
- Correspondence: (J.L.); (G.S.); Tel.: +1-402-472-8098 (J.L.); +1-402-472-4204 (G.S.)
| | - Gautam Sarath
- Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA; (L.P.); (K.G.K.); (T.H.-M.); (J.D.B.)
- Wheat, Sorghum, and Forage Research Unit, USDA-ARS, Lincoln, NE 68583, USA;
- Correspondence: (J.L.); (G.S.); Tel.: +1-402-472-8098 (J.L.); +1-402-472-4204 (G.S.)
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11
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Tetreault HM, Gries T, Palmer NA, Funnell-Harris DL, Sato S, Ge Z, Sarath G, Sattler SE. Overexpression of ferulate 5-hydroxylase increases syringyl units in Sorghum bicolor. PLANT MOLECULAR BIOLOGY 2020; 103:269-285. [PMID: 32170550 DOI: 10.1007/s11103-020-00991-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 03/04/2020] [Indexed: 05/28/2023]
Abstract
Ferulate 5-hydroxylase (F5H) of the monolignol pathway catalyzes the hydroxylation of coniferyl alcohol, coniferaldehyde and ferulic acid to produce 5-hydroxyconiferyl moieties, which lead to the formation of sinapic acid and syringyl (S) lignin monomers. In contrast, guaiacyl (G) lignin, the other major type of lignin monomer, is derived from polymerization of coniferyl alcohol. In this study, the effects of manipulating S-lignin biosynthesis in sorghum (Sorghum bicolor) were evaluated. Overexpression of sorghum F5H (SbF5H), under the control of the CaMV 35S promoter, increased both S-lignin levels and the ratio of S/G lignin, while plant growth and development remained relatively unaffected. Maüle staining of stalk and leaf midrib sections from SbF5H overexpression lines indicated that the lignin composition was altered. Ectopic expression of SbF5H did not affect the gene expression of other monolignol pathway genes. In addition, brown midrib 12-ref (bmr12-ref), a nonsense mutation in the sorghum caffeic acid O-methyltransferase (COMT) was combined with 35S::SbF5H through cross-pollination to examine effects on lignin synthesis. The stover composition from bmr12 35S::SbF5H plants more closely resembled bmr12 stover than 35S::SbF5H or wild-type (WT) stover; S-lignin and total lignin concentrations were decreased relative to WT or 35S::SbF5H. Likewise, expression of upstream monolignol biosynthetic genes was increased in both bmr12 and bmr12 35S::SbF5H relative to WT or 35S::SbF5H. Overall, these results indicated that overexpression of SbF5H did not compensate for the loss of COMT activity. KEY MESSAGE: Overexpression of F5H in sorghum increases S-lignin without increasing total lignin content or affecting plant growth, but it cannot compensate for the loss of COMT activity in monolignol synthesis.
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Affiliation(s)
- Hannah M Tetreault
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, Lincoln, NE, 68583, USA
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - Tammy Gries
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, Lincoln, NE, 68583, USA
| | - Nathan A Palmer
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, Lincoln, NE, 68583, USA
| | - Deanna L Funnell-Harris
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, Lincoln, NE, 68583, USA
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - Shirley Sato
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE, 68588, USA
| | - Zhengxiang Ge
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE, 68588, USA
| | - Gautam Sarath
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, Lincoln, NE, 68583, USA
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - Scott E Sattler
- Wheat, Sorghum and Forage Research Unit, USDA-ARS, Lincoln, NE, 68583, USA.
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA.
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12
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Hennet L, Berger A, Trabanco N, Ricciuti E, Dufayard JF, Bocs S, Bastianelli D, Bonnal L, Roques S, Rossini L, Luquet D, Terrier N, Pot D. Transcriptional Regulation of Sorghum Stem Composition: Key Players Identified Through Co-expression Gene Network and Comparative Genomics Analyses. FRONTIERS IN PLANT SCIENCE 2020; 11:224. [PMID: 32194601 PMCID: PMC7064007 DOI: 10.3389/fpls.2020.00224] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 02/12/2020] [Indexed: 06/10/2023]
Abstract
Most sorghum biomass accumulates in stem secondary cell walls (SCW). As sorghum stems are used as raw materials for various purposes such as feed, energy and fiber reinforced polymers, identifying the genes responsible for SCW establishment is highly important. Taking advantage of studies performed in model species, most of the structural genes contributing at the molecular level to the SCW biosynthesis in sorghum have been proposed while their regulatory factors have mostly not been determined. Validation of the role of several MYB and NAC transcription factors in SCW regulation in Arabidopsis and a few other species has been provided. In this study, we contributed to the recent efforts made in grasses to uncover the mechanisms underlying SCW establishment. We reported updated phylogenies of NAC and MYB in 9 different species and exploited findings from other species to highlight candidate regulators of SCW in sorghum. We acquired expression data during sorghum internode development and used co-expression analyses to determine groups of co-expressed genes that are likely to be involved in SCW establishment. We were able to identify two groups of co-expressed genes presenting multiple evidences of involvement in SCW building. Gene enrichment analysis of MYB and NAC genes provided evidence that while NAC SECONDARY WALL THICKENING PROMOTING FACTOR NST genes and SECONDARY WALL-ASSOCIATED NAC DOMAIN PROTEIN gene functions appear to be conserved in sorghum, NAC master regulators of SCW in sorghum may not be as tissue compartmentalized as in Arabidopsis. We showed that for every homolog of the key SCW MYB in Arabidopsis, a similar role is expected for sorghum. In addition, we unveiled sorghum MYB and NAC that have not been identified to date as being involved in cell wall regulation. Although specific validation of the MYB and NAC genes uncovered in this study is needed, we provide a network of sorghum genes involved in SCW both at the structural and regulatory levels.
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Affiliation(s)
- Lauriane Hennet
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Angélique Berger
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Noemi Trabanco
- Parco Tecnologico Padano, Lodi, Italy
- Centro de Biotecnología y Genómica de Plantas, UPM-INIA, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Emeline Ricciuti
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Jean-François Dufayard
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Stéphanie Bocs
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Denis Bastianelli
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
- CIRAD, UMR SELMET, Montpellier, France
| | - Laurent Bonnal
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
- CIRAD, UMR SELMET, Montpellier, France
| | - Sandrine Roques
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Laura Rossini
- Parco Tecnologico Padano, Lodi, Italy
- Department of Agricultural and Environmental Sciences - Production, Landscape, Agroenergy, Università degli Studi di Milano, Milan, Italy
| | - Delphine Luquet
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Nancy Terrier
- AGAP, CIRAD, INRAE, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - David Pot
- CIRAD, UMR AGAP, Montpellier, France
- CIRAD, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
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13
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Lin CY, Eudes A. Strategies for the production of biochemicals in bioenergy crops. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:71. [PMID: 32318116 PMCID: PMC7158082 DOI: 10.1186/s13068-020-01707-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/02/2020] [Indexed: 05/12/2023]
Abstract
Industrial crops are grown to produce goods for manufacturing. Rather than food and feed, they supply raw materials for making biofuels, pharmaceuticals, and specialty chemicals, as well as feedstocks for fabricating fiber, biopolymer, and construction materials. Therefore, such crops offer the potential to reduce our dependency on petrochemicals that currently serve as building blocks for manufacturing the majority of our industrial and consumer products. In this review, we are providing examples of metabolites synthesized in plants that can be used as bio-based platform chemicals for partial replacement of their petroleum-derived counterparts. Plant metabolic engineering approaches aiming at increasing the content of these metabolites in biomass are presented. In particular, we emphasize on recent advances in the manipulation of the shikimate and isoprenoid biosynthetic pathways, both of which being the source of multiple valuable compounds. Implementing and optimizing engineered metabolic pathways for accumulation of coproducts in bioenergy crops may represent a valuable option for enhancing the commercial value of biomass and attaining sustainable lignocellulosic biorefineries.
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Affiliation(s)
- Chien-Yuan Lin
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Aymerick Eudes
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
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14
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Su X, Zhao Y, Wang H, Li G, Cheng X, Jin Q, Cai Y. Transcriptomic analysis of early fruit development in Chinese white pear (Pyrus bretschneideri Rehd.) and functional identification of PbCCR1 in lignin biosynthesis. BMC PLANT BIOLOGY 2019; 19:417. [PMID: 31604417 PMCID: PMC6788021 DOI: 10.1186/s12870-019-2046-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/20/2019] [Indexed: 05/02/2023]
Abstract
BACKGROUND The content of stone cells and lignin is one of the key factors affecting the quality of pear fruit. In a previous study, we determined the developmental regularity of stone cells and lignin in 'Dangshan Su' pear fruit 15-145 days after pollination (DAP). However, the development of fruit stone cells and lignin before 15 DAP has not been heavily researched. RESULTS In this study, we found that primordial stone cells began to appear at 7 DAP and that the fruit had formed a large number of stone cells at 15 DAP. Subsequently, transcriptome sequencing was performed on fruits at 0, 7, and 15 DAP and identified 3834 (0 vs. 7 DAP), 4049 (7 vs. 15 DAP) and 5763 (0 vs. 15 DAP) DEGs. During the 7-15 DAP period, a large number of key enzyme genes essential for lignin biosynthesis are gradually up-regulated, and their expression pattern is consistent with the accumulation of lignin in this period. Further analysis found that the biosynthesis of S-type lignin in 'Dangshan Su' pear does not depend on the catalytic activity of PbSAD but is primarily generated by the catalytic activity of caffeoyl-CoA through CCoAOMT, CCR, F5H, and CAD. We cloned PbCCR1, 2 and analysed their functions in Chinese white pear lignin biosynthesis. PbCCR1 and 2 have a degree of functional redundancy; both demonstrate the ability to participate in lignin biosynthesis. However, PbCCR1 may be the major gene for lignin biosynthesis, while PbCCR2 has little effect on lignin biosynthesis. CONCLUSIONS Our results revealed that 'Dangshan Su' pear began to form a large number of stone cells and produce lignin after 7 DAP and mainly accumulated materials from 0 to 7 DAP. PbCCR1 is mainly involved in the biosynthesis of lignin in 'Dangshan Su' pear and plays a positive role in lignin biosynthesis.
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Affiliation(s)
- Xueqiang Su
- School of Life Science, Anhui Agricultural University, Hefei, Anhui China
| | - Yu Zhao
- School of Life Science, Anhui Agricultural University, Hefei, Anhui China
| | - Han Wang
- School of Life Science, Anhui Agricultural University, Hefei, Anhui China
| | - Guohui Li
- School of Life Science, Anhui Agricultural University, Hefei, Anhui China
| | - Xi Cheng
- School of Life Science, Anhui Agricultural University, Hefei, Anhui China
| | - Qing Jin
- School of Life Science, Anhui Agricultural University, Hefei, Anhui China
| | - Yongping Cai
- School of Life Science, Anhui Agricultural University, Hefei, Anhui China
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15
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Funnell-Harris DL, Sattler SE, O'Neill PM, Gries T, Tetreault HM, Clemente TE. Response of Sorghum Enhanced in Monolignol Biosynthesis to Stalk Rot Pathogens. PLANT DISEASE 2019; 103:2277-2287. [PMID: 31215851 DOI: 10.1094/pdis-09-18-1622-re] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
To increase phenylpropanoid constituents and energy content in the versatile C4 grass sorghum (Sorghum bicolor [L.] Moench), sorghum genes for proteins related to monolignol biosynthesis were overexpressed: SbMyb60 (transcriptional activator), SbPAL (phenylalanine ammonia lyase), SbCCoAOMT (caffeoyl coenzyme A [CoA] 3-O-methyltransferase), Bmr2 (4-coumarate:CoA ligase), and SbC3H (coumaroyl shikimate 3-hydroxylase). Overexpression lines were evaluated for responses to stalk pathogens under greenhouse and field conditions. Greenhouse-grown plants were inoculated with Fusarium thapsinum (Fusarium stalk rot) and Macrophomina phaseolina (charcoal rot), which cause yield-reducing diseases. F. thapsinum-inoculated overexpression plants had mean lesion lengths not significantly different than wild-type, except for significantly smaller lesions on two of three SbMyb60 and one of two SbCCoAOMT lines. M. phaseolina-inoculated overexpression lines had lesions not significantly different from wild-type except one SbPAL line (of two lines studied) with mean lesion lengths significantly larger. Field-grown SbMyb60 and SbCCoAOMT overexpression plants were inoculated with F. thapsinum. Mean lesions of SbMyb60 lines were similar to wild-type, but one SbCCoAOMT had larger lesions, whereas the other line was not significantly different than wild-type. Because overexpression of SbMyb60, Bmr2, or SbC3H may not render sorghum more susceptible to stalk rots, these lines may provide sources for development of sorghum with increased phenylpropanoid concentrations.
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Affiliation(s)
- Deanna L Funnell-Harris
- Wheat, Sorghum and Forage Research Unit, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Plant Pathology, University of Nebraska, Lincoln, NE 68583
| | - Scott E Sattler
- Wheat, Sorghum and Forage Research Unit, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68583
| | - Patrick M O'Neill
- Wheat, Sorghum and Forage Research Unit, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Plant Pathology, University of Nebraska, Lincoln, NE 68583
| | - Tammy Gries
- Wheat, Sorghum and Forage Research Unit, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68583
| | - Hannah M Tetreault
- Wheat, Sorghum and Forage Research Unit, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Lincoln, NE 68583
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68583
| | - Thomas E Clemente
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68583
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