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McGuire ST, Shockey J, Bates PD. The first intron and promoter of Arabidopsis DIACYLGLYCEROL ACYLTRANSFERASE 1 exert synergistic effects on pollen and embryo lipid accumulation. THE NEW PHYTOLOGIST 2025; 245:263-281. [PMID: 39501618 PMCID: PMC11617664 DOI: 10.1111/nph.20244] [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: 08/24/2024] [Accepted: 10/17/2024] [Indexed: 12/06/2024]
Abstract
Accumulation of triacylglycerols (TAGs) is crucial during various stages of plant development. In Arabidopsis, two enzymes share overlapping functions to produce TAGs, namely acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) and phospholipid:diacylglycerol acyltransferase 1 (PDAT1). Loss of function of both genes in a dgat1-1/pdat1-2 double mutant is gametophyte lethal. However, the key regulatory elements controlling tissue-specific expression of either gene has not yet been identified. We transformed a dgat1-1/dgat1-1//PDAT1/pdat1-2 parent with transgenic constructs containing the Arabidopsis DGAT1 promoter fused to the AtDGAT1 open reading frame either with or without the first intron. Triple homozygous plants were obtained, however, in the absence of the DGAT1 first intron anthers fail to fill with pollen, seed yield is c. 10% of wild-type, seed oil content remains reduced (similar to dgat1-1/dgat1-1), and non-Mendelian segregation of the PDAT1/pdat1-2 locus occurs. Whereas plants expressing the AtDGAT1pro:AtDGAT1 transgene containing the first intron mostly recover phenotypes to wild-type. This study establishes that a combination of the promoter and first intron of AtDGAT1 provides the proper context for temporal and tissue-specific expression of AtDGAT1 in pollen. Furthermore, we discuss possible mechanisms of intron mediated regulation and how regulatory elements can be used as genetic tools to functionally replace TAG biosynthetic enzymes in Arabidopsis.
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Affiliation(s)
- Sean T. McGuire
- Institute of Biological ChemistryWashington State UniversityPullmanWA99164USA
| | - Jay Shockey
- United States Department of Agriculture, Agricultural Research Service, Southern Regional Research Service1100 Allen Toussaint BlvdNew OrleansLA70124USA
| | - Philip D. Bates
- Institute of Biological ChemistryWashington State UniversityPullmanWA99164USA
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2
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Alkotami L, White DJ, Schuler KM, Esfahanian M, Jarvis BA, Paulson AE, Koley S, Kang J, Lu C, Allen DK, Lee YJ, Sedbrook JC, Durrett TP. Targeted engineering of camelina and pennycress seeds for ultrahigh accumulation of acetyl-TAG. Proc Natl Acad Sci U S A 2024; 121:e2412542121. [PMID: 39527733 PMCID: PMC11588082 DOI: 10.1073/pnas.2412542121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Accepted: 10/04/2024] [Indexed: 11/16/2024] Open
Abstract
Acetyl-TAG (3-acetyl-1,2-diacylglycerol), unique triacylglycerols (TAG) possessing an acetate group at the sn-3 position, exhibit valuable properties, such as reduced viscosity and freezing points. Previous attempts to engineer acetyl-TAG production in oilseed crops did not achieve the high levels found in naturally producing Euonymus seeds. Here, we demonstrate the successful generation of camelina and pennycress transgenic lines accumulating nearly pure acetyl-TAG at 93 mol% and 98 mol%, respectively. These ultrahigh acetyl-TAG synthesizing lines were created using gene-edited FATTY ACID ELONGASE1 (FAE1) mutant lines as an improved genetic background to increase levels of acetyl-CoA available for acetyl-TAG synthesis mediated by the expression of EfDAcT, a high-activity diacylglycerol acetyltransferase isolated from Euonymus fortunei. Combining EfDAcT expression with suppression of the competing TAG-synthesizing enzyme DGAT1 further enhanced acetyl-TAG accumulation. These ultrahigh levels of acetyl-TAG exceed those in earlier engineered oilseeds and are equivalent or greater than those in Euonymus seeds. Imaging of lipid localization in transgenic seeds revealed that the low amounts of residual TAG were mostly confined to the embryonic axis. Similar spatial distributions of specific TAG and acetyl-TAG molecular species, as well as their probable diacylglycerol (DAG) precursors, provide additional evidence that acetyl-TAG and TAG are both synthesized from the same tissue-specific DAG pools. Remarkably, this ultrahigh production of acetyl-TAG in transgenic seeds exhibited minimal negative effects on seed properties, highlighting the potential for production of designer oils required for economical biofuel industries.
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Affiliation(s)
- Linah Alkotami
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS66506
| | - Dexter J. White
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS66506
| | | | - Maliheh Esfahanian
- School of Biological Sciences, Illinois State University, Normal, IL61790
| | - Brice A. Jarvis
- School of Biological Sciences, Illinois State University, Normal, IL61790
| | | | - Somnath Koley
- Donald Danforth Plant Science Center, St. Louis, MO63132
| | - Jinling Kang
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT59717
| | - Chaofu Lu
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT59717
| | - Doug K. Allen
- Donald Danforth Plant Science Center, St. Louis, MO63132
- United States Department of Agriculture, Agricultural Research Service, St. Louis, MO63132
| | - Young-Jin Lee
- Department of Chemistry, Iowa State University, Ames, IA50011
| | - John C. Sedbrook
- School of Biological Sciences, Illinois State University, Normal, IL61790
| | - Timothy P. Durrett
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS66506
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3
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Lee KR, Park ME, Kim HU. Domestication and engineering of pennycress (Thlaspi arvense L.): challenges and opportunities for sustainable bio-based feedstocks. PLANTA 2024; 260:127. [PMID: 39470818 DOI: 10.1007/s00425-024-04560-6] [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: 02/23/2024] [Accepted: 10/19/2024] [Indexed: 11/01/2024]
Abstract
MAIN CONCLUSION Pennycress, as an emerging oilseed crop with high oil content, faces challenges but offers potential for sustainable bioproducts; ongoing research aims to enhance its traits and quality. Pennycress (Thlaspi arvense L.) is an emerging oilseed crop with many advantages, such as high seed oil (27-39%) and monounsaturated fatty acid (55.6%) content, making it an attractive candidate to produce sustainable bioproducts. However, several challenges are associated with domesticating pennycress, including high silicle shatter, which reduces seed yield during harvest, non-uniformed germination rate and high contents of erucic acid and glucosinolates, which have adverse health effects on humans and animals. Pennycress, which can be easily and rapidly transformed using the floral dip method under vacuum, can achieve trait improvements. Ongoing research for pennycress domestication using mutation breeding, including ethylmethylsulfonate treatment and genome editing, aims to improve its quality. Pennycress can be used as an excellent platform for producing industrially important fatty acids such as hydroxy and epoxy fatty acids and docosahexaenoic acid. In conclusion, pennycress is a promising oilseed crop with multiple advantages and potential applications. Continuous improvements in quality and engineering for producing high-value bio-based feedstocks in pennycress will establish it as a sustainable and economically valuable crop.
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Affiliation(s)
- Kyeong-Ryeol Lee
- Department of Agricultural Biotechnology, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju, 54875, Republic of Korea
| | - Mid-Eum Park
- Department of Molecular Biology, Sejong University, Seoul, 05006, Republic of Korea
| | - Hyun Uk Kim
- Department of Molecular Biology, Sejong University, Seoul, 05006, Republic of Korea.
- Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 05006, Republic of Korea.
- Plant Engineering Research Institute, Sejong University, Seoul, 05006, Republic of Korea.
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Abdullah HM, Pang N, Chilcoat B, Shachar-Hill Y, Schnell DJ, Dhankher OP. Overexpression of the Phosphatidylcholine:DiacylglycerolCholinephosphotransferase (PDCT) gene increases carbon flux toward triacylglycerol (TAG) synthesis in Camelinasativa seeds. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 208:108470. [PMID: 38422576 DOI: 10.1016/j.plaphy.2024.108470] [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: 04/04/2023] [Revised: 12/22/2023] [Accepted: 02/23/2024] [Indexed: 03/02/2024]
Abstract
Camelinasativa has considerable promise as a dedicated industrial oilseed crop. Its oil-based blends have been tested and approved as liquid transportation fuels. Previously, we utilized metabolomic and transcriptomic profiling approaches and identified metabolic bottlenecks that control oil production and accumulation in seeds. Accordingly, we selected candidate genes for the metabolic engineering of Camelina. Here we targeted the overexpression of Camelina PDCT gene, which encodes the phosphatidylcholine: diacylglycerol cholinephosphotransferase enzyme. PDCT is proposed as a gatekeeper responsible for the interconversions of diacylglycerol (DAG) and phosphatidylcholine (PC) pools and has the potential to increase the levels of TAG in seeds. To confirm whether increased CsPDCT activity in developing Camelina seeds would enhance carbon flux toward increased levels of TAG and alter oil composition, we overexpressed the CsPDCT gene under the control of the seed-specific phaseolin promoter. Camelina transgenics exhibited significant increases in seed yield (19-56%), seed oil content (9-13%), oil yields per plant (32-76%), and altered polyunsaturated fatty acid (PUFA) content compared to their parental wild-type (WT) plants. Results from [14C] acetate labeling of Camelina developing embryos expressing CsPDCT in culture indicated increased rates of radiolabeled fatty acid incorporation into glycerolipids (up to 64%, 59%, and 43% higher in TAG, DAG, and PC, respectively), relative to WT embryos. We conclude that overexpression of PDCT appears to be a positive strategy to achieve a synergistic effect on the flux through the TAG synthesis pathway, thereby further increasing oil yields in Camelina.
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Affiliation(s)
- Hesham M Abdullah
- Stockbridge School of Agriculture, University of Massachusetts Amherst, MA, 01003, USA; Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA; Biotechnology Department, Faculty of Agriculture, Al-Azhar University, Cairo, 11651, Egypt.
| | - Na Pang
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Benjamin Chilcoat
- Stockbridge School of Agriculture, University of Massachusetts Amherst, MA, 01003, USA
| | - Yair Shachar-Hill
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Danny J Schnell
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Om Parkash Dhankher
- Stockbridge School of Agriculture, University of Massachusetts Amherst, MA, 01003, USA.
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Huang D, Gao L, McAdams J, Zhao F, Lu H, Wu Y, Martin J, Sherif SM, Subramanian J, Duan H, Liu W. Engineered Cleistogamy in Camelina sativa for bioconfinement. HORTICULTURE RESEARCH 2023; 10:uhac280. [PMID: 36793756 PMCID: PMC9926159 DOI: 10.1093/hr/uhac280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 12/07/2022] [Indexed: 06/18/2023]
Abstract
Camelina sativa is a self-pollinating and facultative outcrossing oilseed crop. Genetic engineering has been used to improve camelina yield potential for altered fatty acid composition, modified protein profiles, improved seed and oil yield, and enhanced drought resistance. The deployment of transgenic camelina in the field posits high risks related to the introgression of transgenes into non-transgenic camelina and wild relatives. Thus, effective bioconfinement strategies need to be developed to prevent pollen-mediated gene flow (PMGF) from transgenic camelina. In the present study, we overexpressed the cleistogamy (i.e. floral petal non-openness)-inducing PpJAZ1 gene from peach in transgenic camelina. Transgenic camelina overexpressing PpJAZ1 showed three levels of cleistogamy, affected pollen germination rates after anthesis but not during anthesis, and caused a minor silicle abortion only on the main branches. We also conducted field trials to examine the effects of the overexpressed PpJAZ1 on PMGF in the field, and found that the overexpressed PpJAZ1 dramatically inhibited PMGF from transgenic camelina to non-transgenic camelina under the field conditions. Thus, the engineered cleistogamy using the overexpressed PpJAZ1 is a highly effective bioconfinement strategy to limit PMGF from transgenic camelina, and could be used for bioconfinement in other dicot species.
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Affiliation(s)
- Debao Huang
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27607, USA
| | - Liwei Gao
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27607, USA
- College of Life Sciences, Ganzhou Normal University, Ganzhou, Jiangxi 341000, China
| | - Jeremy McAdams
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27607, USA
| | - Fangzhou Zhao
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27607, USA
- National Center for Soybean Improvement, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Hongyan Lu
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27607, USA
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, Hubei 430048, China
| | - Yonghui Wu
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27607, USA
| | - Jeremy Martin
- Sandhills Research Station, North Carolina State University, Jackson Springs, NC 27281, USA
| | - Sherif M Sherif
- Vineland Research Station, Department of Plant Agriculture, University of Guelph, Vinland Station, ON LOR 2E0, Canada
- Alson H. Smith Jr. Agricultural Research and Extension Center, School of Plant and Environmental Sciences, Virginia Tech, Winchester, VA 22602, USA
| | - Jayasankar Subramanian
- Vineland Research Station, Department of Plant Agriculture, University of Guelph, Vinland Station, ON LOR 2E0, Canada
| | - Hui Duan
- Alson H. Smith Jr. Agricultural Research and Extension Center, School of Plant and Environmental Sciences, Virginia Tech, Winchester, VA 22602, USA
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Cai Y, Yu XH, Shanklin J. A toolkit for plant lipid engineering: Surveying the efficacies of lipogenic factors for accumulating specialty lipids. FRONTIERS IN PLANT SCIENCE 2022; 13:1064176. [PMID: 36589075 PMCID: PMC9795026 DOI: 10.3389/fpls.2022.1064176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Plants produce energy-dense lipids from carbohydrates using energy acquired via photosynthesis, making plant oils an economically and sustainably attractive feedstock for conversion to biofuels and value-added bioproducts. A growing number of strategies have been developed and optimized in model plants, oilseed crops and high-biomass crops to enhance the accumulation of storage lipids (mostly triacylglycerols, TAGs) for bioenergy applications and to produce specialty lipids with increased uses and value for chemical feedstock and nutritional applications. Most successful metabolic engineering strategies involve heterologous expression of lipogenic factors that outperform those from other sources or exhibit specialized functionality. In this review, we summarize recent progress in engineering the accumulation of triacylglycerols containing - specialized fatty acids in various plant species and tissues. We also provide an inventory of specific lipogenic factors (including accession numbers) derived from a wide variety of organisms, along with their reported efficacy in supporting the accumulation of desired lipids. A review of previously obtained results serves as a foundation to guide future efforts to optimize combinations of factors to achieve further enhancements to the production and accumulation of desired lipids in a variety of plant tissues and species.
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Affiliation(s)
- Yingqi Cai
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
| | - Xiao-Hong Yu
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, United States
| | - John Shanklin
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
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7
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Trenz TS, Turchetto-Zolet AC, Margis R, Margis-Pinheiro M, Maraschin FDS. Functional analysis of alternative castor bean DGAT enzymes. Genet Mol Biol 2022; 46:e20220097. [PMID: 36512712 PMCID: PMC9747089 DOI: 10.1590/1678-4685-gmb-2022-0097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 10/30/2022] [Indexed: 12/14/2022] Open
Abstract
The diversity of diacylglycerol acyltransferases (DGATs) indicates alternative roles for these enzymes in plant metabolism besides triacylglycerol (TAG) biosynthesis. In this work, we functionally characterized castor bean (Ricinus communis L.) DGATs assessing their subcellular localization, expression in seeds, capacity to restore triacylglycerol (TAG) biosynthesis in mutant yeast and evaluating whether they provide tolerance over free fatty acids (FFA) in sensitive yeast. RcDGAT3 displayed a distinct subcellular localization, located in vesicles outside the endoplasmic reticulum (ER) in most leaf epidermal cells. This enzyme was unable to restore TAG biosynthesis in mutant yeast; however, it was able to outperform other DGATs providing higher tolerance over FFA. RcDAcTA subcellular localization was associated with the ER membranes, resembling RcDGAT1 and RcDGAT2, but it failed to rescue the long-chain TAG biosynthesis in mutant yeast, even with fatty acid supplementation. Besides TAG biosynthesis, our results suggest that RcDGAT3 might have alternative functions and roles in lipid metabolism.
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Affiliation(s)
- Thomaz Stumpf Trenz
- Universidade Federal do Rio Grande do Sul, Programa de Pós-graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Porto Alegre, RS, Brazil
| | - Andreia Carina Turchetto-Zolet
- Universidade Federal do Rio Grande do Sul, Programa de Pós-graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Instituto de Biociências, Departamento de Genética, Porto Alegre, RS, Brazil
| | - Rogério Margis
- Universidade Federal do Rio Grande do Sul, Programa de Pós-graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Programa de Pós-graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Instituto de Biociências, Departamento de Biofísica, Porto Alegre, RS, Brazil
| | - Marcia Margis-Pinheiro
- Universidade Federal do Rio Grande do Sul, Programa de Pós-graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Programa de Pós-graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Instituto de Biociências, Departamento de Genética, Porto Alegre, RS, Brazil
| | - Felipe dos Santos Maraschin
- Universidade Federal do Rio Grande do Sul, Programa de Pós-graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil.,Universidade Federal do Rio Grande do Sul, Instituto de Biociências, Departamento de Botânica, Porto Alegre, RS, Brazil
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