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Wang K, Zhou Y, Cao L, Lin L, Ledesma-Amaro R, Ji XJ. Engineering Yarrowia lipolytica for Sustainable Production of the Pomegranate Seed Oil-Derived Punicic Acid. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:3088-3098. [PMID: 38282297 DOI: 10.1021/acs.jafc.3c08718] [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: 01/30/2024]
Abstract
Punicic acid is a conjugated linolenic acid with various biological activities including antiobesity, antioxidant, anticancer, and anti-inflammatory effects. It is often used as a nutraceutical, dietary additive, and animal feed. Currently, punicic acid is primarily extracted from pomegranate seed oil, but it is restricted due to the extended growth cycle, climatic limitations, and low recovery level. There have also been reports on the chemical synthesis of punicic acid, but it resulted in a mixture of structurally similar isomers, requiring additional purification/separation steps. In this study, a comprehensive strategy for the production of punicic acid in Yarrowia lipolytica was implemented by pushing the supply of linoleic acid precursors in a high-oleic oil strain, expressing multiple copies of the fatty acid conjugase gene from Punica granatum, engineering the acyl-editing pathway to improve the phosphatidylcholine pool, and promoting the assembly of punicic acid in the form of triglycerides. The optimal strain with high oil production capacity and a significantly increased punicic acid ratio accumulated 3072.72 mg/L punicic acid, accounting for 6.19% of total fatty acids in fed-batch fermentation, providing a viable, sustainable, and green approach for punicic acid production to substitute plant extraction and chemical synthesis production.
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Affiliation(s)
- Kaifeng Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Yueyue Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Lizhen Cao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Lu Lin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Rodrigo Ledesma-Amaro
- Department of Bioengineering and Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, U.K
| | - Xiao-Jun Ji
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing 211816, People's Republic of China
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2
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Hrach VL, King WR, Nelson LD, Conklin S, Pollock JA, Patton-Vogt J. The acyltransferase Gpc1 is both a target and an effector of the unfolded protein response in Saccharomyces cerevisiae. J Biol Chem 2023; 299:104884. [PMID: 37269946 PMCID: PMC10331479 DOI: 10.1016/j.jbc.2023.104884] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 05/25/2023] [Accepted: 05/27/2023] [Indexed: 06/05/2023] Open
Abstract
The unfolded protein response (UPR) is sensitive to proteotoxic and membrane bilayer stress, both of which are sensed by the ER protein Ire1. When activated, Ire1 splices HAC1 mRNA, producing a transcription factor that targets genes involved in proteostasis and lipid metabolism, among others. The major membrane lipid phosphatidylcholine (PC) is subject to phospholipase-mediated deacylation, producing glycerophosphocholine (GPC), followed by reacylation of GPC through the PC deacylation/reacylation pathway (PC-DRP). The reacylation events occur via a two-step process catalyzed first by the GPC acyltransferase Gpc1, followed by acylation of the lyso-PC molecule by Ale1. However, whether Gpc1 is critical for ER bilayer homeostasis is unclear. Using an improved method for C14-choline-GPC radiolabeling, we first show that loss of Gpc1 results in abrogation of PC synthesis through PC-DRP and that Gpc1 colocalizes with the ER. We then probe the role of Gpc1 as both a target and an effector of the UPR. Exposure to the UPR-inducing compounds tunicamycin, DTT, and canavanine results in a Hac1-dependent increase in GPC1 message. Further, cells lacking Gpc1 exhibit increased sensitivity to those proteotoxic stressors. Inositol limitation, known to induce the UPR via bilayer stress, also induces GPC1 expression. Finally, we show that loss of GPC1 induces the UPR. A gpc1Δ mutant displays upregulation of the UPR in strains expressing a mutant form of Ire1 that is unresponsive to unfolded proteins, indicating that bilayer stress is responsible for the observed upregulation. Collectively, our data indicate an important role for Gpc1 in yeast ER bilayer homeostasis.
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Affiliation(s)
- Victoria Lee Hrach
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - William R King
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Laura D Nelson
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Shane Conklin
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - John A Pollock
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA.
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3
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Hoffmann DY, Shachar-Hill Y. Do betaine lipids replace phosphatidylcholine as fatty acid editing hubs in microalgae? FRONTIERS IN PLANT SCIENCE 2023; 14:1077347. [PMID: 36743481 PMCID: PMC9892843 DOI: 10.3389/fpls.2023.1077347] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Acyl editing refers to a deacylation and reacylation cycle on a lipid, which allows for fatty acid desaturation and modification prior to being removed and incorporated into other pools. Acyl editing is an important determinant of glycerolipid synthesis and has been well-characterized in land plants, thus this review begins with an overview of acyl editing in plants. Much less is known about acyl editing in algae, including the extent to which acyl editing impacts lipid synthesis and on which lipid substrate(s) it occurs. This review compares what is known about acyl editing on its major hub phosphatidylcholine (PC) in land plants with the evidence for acyl editing of betaine lipids such as diacylglyceryltrimethylhomoserine (DGTS), the structural analog that replaces PC in several species of microalgae. In land plants, PC is also known to be a major source of fatty acids and diacylglycerol (DAG) for synthesis of the neutral lipid triacylglycerol (TAG). We review the evidence that DGTS contributes substantially to TAG accumulation in algae as a source of fatty acids, but not as a precursor to DAG. We conclude with evidence of acyl editing on other membrane lipid substrates in plants and algae apart from PC or DGTS, and discuss future analyses to elucidate the role of DGTS and other betaine lipids in acyl editing in microalgae.
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4
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Park ME, Lee KR, Chen GQ, Kim HU. Enhanced production of hydroxy fatty acids in Arabidopsis seed through modification of multiple gene expression. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:66. [PMID: 35717237 PMCID: PMC9206371 DOI: 10.1186/s13068-022-02167-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 06/09/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Castor (Ricinus communis L.) seeds contain unusual fatty acid, hydroxy fatty acid (HFA) used as a chemical feedstock for numerous industrial products. Castor cultivation is limited by the potent toxin ricin in its seeds and other poor agronomic traits, so it is advantageous to develop a suitable HFA-producing crop. Significant research efforts have been made to produce HFA in model Arabidopsis, but the level of HFA produced in transgenic Arabidopsis is much less than the level found in castor seeds which produce 90% HFA in seed oil. RESULTS We designed a transformation construct that allowed co-expression of five essential castor genes (named pCam5) involved in HFA biosynthesis, including an oleate [Formula: see text] 12-hydroxylase (FAH12), diacylglycerol (DAG) acyltransferase 2 (DGAT2), phospholipid: DAG acyltransferase 1-2 (PDAT1-2), phosphatidylcholine (PC): DAG cholinephosphotransferase (PDCT) and Lyso-PC acyltransferase (LPCAT). Transgenic Arabidopsis pCam5 lines produced HFA counting for 25% in seed oil. By knocking out Arabidopsis Fatty acid elongase 1 (AtFAE1) in pCam5 using CRISPR/Cas9 technology, the resulted pCam5-atfae1 lines produced over 31% of HFA. Astonishingly, the pCam5-atfae1 line increased seed size, weight, and total oil per seed exceeding wild type by 40%. Seed germination, seedling growth and seed mucilage content of pCam5-atfae1 lines were not affected by the genetic modification. CONCLUSIONS Our results provide not only insights for future research uncovering mechanisms of HFA synthesis in seed, but also metabolic engineering strategies for generating safe HFA-producing crops.
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Affiliation(s)
- Mid-Eum Park
- grid.263333.40000 0001 0727 6358Department of Molecular Biology, Sejong University, Seoul, Republic of Korea
| | - Kyeong-Ryeol Lee
- grid.420186.90000 0004 0636 2782Department of Agricultural Biotechnology, Rural Development Administration, National Institute of Agricultural Sciences, Jeonju, Republic of Korea
| | - Grace Q. Chen
- grid.417548.b0000 0004 0478 6311Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA USA
| | - Hyun Uk Kim
- grid.263333.40000 0001 0727 6358Department of Molecular Biology, Sejong University, Seoul, Republic of Korea ,grid.263333.40000 0001 0727 6358Department of Bioindustry and Bioresource Engineering, Plant Engineering Research Institute, Sejong University, Seoul, 05006 Republic of Korea
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5
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Wallis JG, Bengtsson JD, Browse J. Molecular Approaches Reduce Saturates and Eliminate trans Fats in Food Oils. FRONTIERS IN PLANT SCIENCE 2022; 13:908608. [PMID: 35720592 PMCID: PMC9205222 DOI: 10.3389/fpls.2022.908608] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/02/2022] [Indexed: 05/29/2023]
Abstract
Vegetable oils composed of triacylglycerols (TAG) are a major source of calories in human diets. However, the fatty acid compositions of these oils are not ideal for human nutrition and the needs of the food industry. Saturated fatty acids contribute to health problems, while polyunsaturated fatty acids (PUFA) can become rancid upon storage or processing. In this review, we first summarize the pathways of fatty acid metabolism and TAG synthesis and detail the problems with the oil compositions of major crops. Then we describe how transgenic expression of desaturases and downregulation of the plastid FatB thioesterase have provided the means to lower oil saturates. The traditional solution to PUFA rancidity uses industrial chemistry to reduce PUFA content by partial hydrogenation, but this results in the production of trans fats that are even more unhealthy than saturated fats. We detail the discoveries in the biochemistry and molecular genetics of oil synthesis that provided the knowledge and tools to lower oil PUFA content by blocking their synthesis during seed development. Finally, we describe the successes in breeding and biotechnology that are giving us new, high-oleic, low PUFA varieties of soybean, canola and other oilseed crops.
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Affiliation(s)
| | | | - John Browse
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
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6
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Lunn D, Wallis JG, Browse J. A multigene approach secures hydroxy fatty acid production in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:2875-2888. [PMID: 35560203 DOI: 10.1093/jxb/erab533] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 12/02/2021] [Indexed: 06/15/2023]
Abstract
A central goal of green chemistry is to produce industrially useful fatty acids in oilseed crops. Although genes encoding suitable fatty acid-modifying enzymes are available from more than a dozen wild species, progress has been limited because expression of these enzymes in transgenic plants produces only low yields of the desired products. For example, fatty acid hydroxylase 12 (FAH12) from castor (Ricinus communis) produces only 17% hydroxy fatty acids (HFAs) when expressed in Arabidopsis (Arabidopsis thaliana), compared with 90% HFAs in castor seeds. The transgenic plants also have reduced oil content and seed vigor. Here, we review experiments that have provided for steady increased HFA accumulation and oil content. This research has led to exciting new discoveries of enzymes and regulatory processes in the pathways of both seed oil synthesis and lipid metabolism in other parts of the plant. Recent investigations have revealed that HFA-accumulating seeds are unable to rapidly mobilize HFA-containing triacylglycerol (TAG) storage lipid after germination to provide carbon and energy for seedling development, resulting in reduced seedling establishment. These findings present a new opportunity to investigate a different, key area of lipid metabolism-the pathways of TAG lipolysis and β-oxidation in germinating seedlings.
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Affiliation(s)
- Daniel Lunn
- Institute of Biology Chemistry, Washington State University, Pullman, WA 99164-6340, USA
| | - James G Wallis
- Institute of Biology Chemistry, Washington State University, Pullman, WA 99164-6340, USA
| | - John Browse
- Institute of Biology Chemistry, Washington State University, Pullman, WA 99164-6340, USA
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7
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Yu L, Zhou C, Fan J, Shanklin J, Xu C. Mechanisms and functions of membrane lipid remodeling in plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:37-53. [PMID: 33853198 DOI: 10.1111/tpj.15273] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/05/2021] [Accepted: 04/08/2021] [Indexed: 05/20/2023]
Abstract
Lipid remodeling, defined herein as post-synthetic structural modifications of membrane lipids, play crucial roles in regulating the physicochemical properties of cellular membranes and hence their many functions. Processes affected by lipid remodeling include lipid metabolism, membrane repair, cellular homeostasis, fatty acid trafficking, cellular signaling and stress tolerance. Glycerolipids are the major structural components of cellular membranes and their composition can be adjusted by modifying their head groups, their acyl chain lengths and the number and position of double bonds. This review summarizes recent advances in our understanding of mechanisms of membrane lipid remodeling with emphasis on the lipases and acyltransferases involved in the modification of phosphatidylcholine and monogalactosyldiacylglycerol, the major membrane lipids of extraplastidic and photosynthetic membranes, respectively. We also discuss the role of triacylglycerol metabolism in membrane acyl chain remodeling. Finally, we discuss emerging data concerning the functional roles of glycerolipid remodeling in plant stress responses. Illustrating the molecular basis of lipid remodeling may lead to novel strategies for crop improvement and other biotechnological applications such as bioenergy production.
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Affiliation(s)
- Linhui Yu
- Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Chao Zhou
- Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Jilian Fan
- Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - John Shanklin
- Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Changcheng Xu
- Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
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8
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Gopalam R, Tumaney AW. Functional characterization of acyltransferases from Salvia hispanica that can selectively catalyze the formation of trilinolenin. PHYTOCHEMISTRY 2021; 186:112712. [PMID: 33706110 DOI: 10.1016/j.phytochem.2021.112712] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 02/19/2021] [Accepted: 02/20/2021] [Indexed: 06/12/2023]
Abstract
Salvia hispanica (chia) is an important oilseed crop cultivated commercially in South America, Australia, and India. It is the richest terrestrial natural source of α-linolenic acid (ALA), an ω-3 polyunsaturated fatty acid with varied health benefits. In this study, we have measured the total lipid content, fatty acid composition in four phases of seed development and analyzed the major triacylglycerol (TAG) molecular species present in Indian chia seed oil. We found that the mature seeds produced 28% oil, 65% of ALA, and trilinolenin as the major TAG species. To make TAG rich in ALA, there should be specialized enzymes that can efficiently transfer ALA to TAG. To study this hypothesis, we performed a characterization of TAG synthesizing enzymes present in chia. We have identified two acyl CoA:diacylglycerol acyltransferases (ShDGAT1 and ShDGAT2) and one phospholipid:diacylglycerol acyltransferase (ShPDAT1) from the chia transcriptome data. Functional characterization of these enzymes was conducted by heterologous expression in a TAG deficient mutant of Saccharomyces cerevisiae. Substrate specificity studies showed that ShDGAT2-1 and ShPDAT1 exhibited a strong preference towards substrates containing ALA and could incorporate 45% and 80% ALA into TAG, respectively. Both enzymes incorporated ALA in a concentration-dependent manner into TAG and were able to form trilinolenin in yeast. Our results provide a first insight into the high ALA accumulation in chia and the first demonstration of trilinolenin formation by DGAT2. The two identified enzymes (ShDGAT2-1 and ShPDAT1) can be used to metabolically engineer other oilseed crops to produce high levels of ALA.
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Affiliation(s)
- Rahul Gopalam
- Department of Lipid Science, CSIR-Central Food Technological Research Institute (CSIR-CFTRI), Mysore, 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Ajay W Tumaney
- Department of Lipid Science, CSIR-Central Food Technological Research Institute (CSIR-CFTRI), Mysore, 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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9
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Latha M, Dolui AK, Vijayaraj P. Proteoform of Arabidopsis seed storage protein identified by functional proteomics approach exhibits acyl hydrolase activity during germination. Int J Biol Macromol 2021; 172:452-463. [PMID: 33454325 DOI: 10.1016/j.ijbiomac.2021.01.074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 02/01/2023]
Abstract
Lipases play a crucial role in the life cycle of seed plants and the oil content of the seed is highly regulated by the lipase activity. Hence, understanding the role of lipases during germination and post-germination will provide insights into lipid mobilization. However, to date, no lipase gene has been identified in seeds except, Sugar-dependent-1 in Arabidopsis. Hence, in the present study, we employed a functional proteomic approach for the identification of seed-specific lipase. Activity-Based Proteome Profiling (ABPP) of Arabidopsis mature and germinating seeds revealed the expression of a functional serine hydrolase exclusively during germination. The mass-spectrometry analysis reveals the identity and amino acid sequence of the protein correspond to AT4G28520 gene, a canonical 12S Seed Storage Protein (SSP). Interestingly, the identified SSP was a proteoform of AT4G28520 (SL-AT4G28520) and exhibited >90% identity with the canonical AT4G28520 (FL-AT4G28520). Heterologous expression and enzyme assays indicated that SL-AT4G28520 protein indeed possesses monoacylglycerol lipase activity, while the FL-AT4G28520 protein didn't exhibit any detectable activity. Functional proteomics and lipidomics analysis demonstrated a catalytic function of this SSP. Collectively, this is the first report, which suggests that SL-AT4G28520 encodes a lipase, and the activity is depending on the physiological condition.
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Affiliation(s)
- Mahadev Latha
- Lipid and Nutrition Laboratory, Department of Lipid Science, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysore, Karnataka 570020, India; Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Achintya Kumar Dolui
- Lipid and Nutrition Laboratory, Department of Lipid Science, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysore, Karnataka 570020, India; Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Panneerselvam Vijayaraj
- Lipid and Nutrition Laboratory, Department of Lipid Science, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysore, Karnataka 570020, India; Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India.
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10
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Regmi A, Shockey J, Kotapati HK, Bates PD. Oil-Producing Metabolons Containing DGAT1 Use Separate Substrate Pools from those Containing DGAT2 or PDAT. PLANT PHYSIOLOGY 2020; 184:720-737. [PMID: 32732347 PMCID: PMC7536707 DOI: 10.1104/pp.20.00461] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 07/23/2020] [Indexed: 05/03/2023]
Abstract
Seed triacylglycerol (TAG) biosynthesis involves a metabolic network containing multiple different diacylglycerol (DAG) and acyl donor substrate pools. This network of pathways overlaps with those for essential membrane lipid synthesis and utilizes multiple different classes of TAG biosynthetic enzymes. Acyl flux through this network ultimately dictates the final oil fatty acid composition. Most strategies to alter seed oil composition involve the overexpression of lipid biosynthetic enzymes, but how these enzymes are assembled into metabolons and which substrate pools are used by each is still not well understood. To understand the roles of different classes of TAG biosynthetic acyltransferases in seed oil biosynthesis, we utilized the Arabidopsis (Arabidopsis thaliana) diacylglycerol acyltransferase mutant dgat1-1 (in which phosphatidylcholine:diacylglycerol acyltransferase (AtPDAT1) is the major TAG biosynthetic enzyme), and enhanced TAG biosynthesis by expression of Arabidopsis acyltransferases AtDGAT1 and AtDGAT2, as well as the DGAT2 enzymes from soybean (Glycine max), and castor (Ricinus communis), followed by isotopic tracing of glycerol flux through the lipid metabolic network in developing seeds. The results indicate each acyltransferase has a unique effect on seed oil composition. AtDGAT1 produces TAG from a rapidly produced phosphatidylcholine-derived DAG pool. However, AtPDAT1 and plant DGAT2 enzymes utilize a different and larger bulk phosphatidylcholine-derived DAG pool that is more slowly turned over for TAG biosynthesis. Based on metabolic fluxes and protein:protein interactions, our model of TAG synthesis suggests that substrate channeling to select enzymes and spatial separation of different acyltransferases into separate metabolons affect efficient TAG production and oil fatty acid composition.
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Affiliation(s)
- Anushobha Regmi
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, Mississippi 39406
| | - Jay Shockey
- United States Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, New Orleans, Louisiana 70124
| | - Hari Kiran Kotapati
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164
| | - Philip D Bates
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, Mississippi 39406
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164
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11
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Correa SM, Alseekh S, Atehortúa L, Brotman Y, Ríos-Estepa R, Fernie AR, Nikoloski Z. Model-assisted identification of metabolic engineering strategies for Jatropha curcas lipid pathways. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:76-95. [PMID: 33001507 DOI: 10.1111/tpj.14906] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/03/2020] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Efficient approaches to increase plant lipid production are necessary to meet current industrial demands for this important resource. While Jatropha curcas cell culture can be used for in vitro lipid production, scaling up the system for industrial applications requires an understanding of how growth conditions affect lipid metabolism and yield. Here we present a bottom-up metabolic reconstruction of J. curcas supported with labeling experiments and biomass characterization under three growth conditions. We show that the metabolic model can accurately predict growth and distribution of fluxes in cell cultures and use these findings to pinpoint energy expenditures that affect lipid biosynthesis and metabolism. In addition, by using constraint-based modeling approaches we identify network reactions whose joint manipulation optimizes lipid production. The proposed model and computational analyses provide a stepping stone for future rational optimization of other agronomically relevant traits in J. curcas.
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Affiliation(s)
- Sandra M Correa
- Genetics of Metabolic Traits Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, 14476, Germany
- Grupo de Biotecnología, Departamento de Ciencias Exactas y Naturales, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Saleh Alseekh
- Central Metabolism Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, 14476, Germany
- Centre for Plant Systems Biology and Biotechnology, Plovdiv, 4000, Bulgaria
| | - Lucía Atehortúa
- Grupo de Biotecnología, Departamento de Ciencias Exactas y Naturales, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Yariv Brotman
- Genetics of Metabolic Traits Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, 14476, Germany
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, 8410501, Israel
| | - Rigoberto Ríos-Estepa
- Grupo de Bioprocesos, Departamento de Ingeniería Química, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Alisdair R Fernie
- Central Metabolism Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, 14476, Germany
- Centre for Plant Systems Biology and Biotechnology, Plovdiv, 4000, Bulgaria
| | - Zoran Nikoloski
- Centre for Plant Systems Biology and Biotechnology, Plovdiv, 4000, Bulgaria
- Bioinformatics, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, 14476, Germany
- Systems Biology and Mathematical Modelling Group, Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
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12
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Correa SM, Fernie AR, Nikoloski Z, Brotman Y. Towards model-driven characterization and manipulation of plant lipid metabolism. Prog Lipid Res 2020; 80:101051. [PMID: 32640289 DOI: 10.1016/j.plipres.2020.101051] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 06/20/2020] [Accepted: 06/21/2020] [Indexed: 01/09/2023]
Abstract
Plant lipids have versatile applications and provide essential fatty acids in human diet. Therefore, there has been a growing interest to better characterize the genetic basis, regulatory networks, and metabolic pathways that shape lipid quantity and composition. Addressing these issues is challenging due to context-specificity of lipid metabolism integrating environmental, developmental, and tissue-specific cues. Here we systematically review the known metabolic pathways and regulatory interactions that modulate the levels of storage lipids in oilseeds. We argue that the current understanding of lipid metabolism provides the basis for its study in the context of genome-wide plant metabolic networks with the help of approaches from constraint-based modeling and metabolic flux analysis. The focus is on providing a comprehensive summary of the state-of-the-art of modeling plant lipid metabolic pathways, which we then contrast with the existing modeling efforts in yeast and microalgae. We then point out the gaps in knowledge of lipid metabolism, and enumerate the recent advances of using genome-wide association and quantitative trait loci mapping studies to unravel the genetic regulations of lipid metabolism. Finally, we offer a perspective on how advances in the constraint-based modeling framework can propel further characterization of plant lipid metabolism and its rational manipulation.
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Affiliation(s)
- Sandra M Correa
- Genetics of Metabolic Traits Group, Max Planck Institute for Molecular Plant Physiology, Potsdam 14476, Germany; Department of Life Sciences, Ben-Gurion University of the Negev, 8410501 Beer-Sheva, Israel; Departamento de Ciencias Exactas y Naturales, Universidad de Antioquia, Medellín 050010, Colombia.
| | - Alisdair R Fernie
- Central Metabolism Group, Max Planck Institute for Molecular Plant Physiology, Potsdam 14476, Germany; Center of Plant Systems Biology and Biotechnology, Plovdiv, Bulgaria
| | - Zoran Nikoloski
- Center of Plant Systems Biology and Biotechnology, Plovdiv, Bulgaria; Bioinformatics, Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany; Systems Biology and Mathematical Modelling Group, Max Planck Institute for Molecular Plant Physiology, Potsdam-Golm 14476, Germany.
| | - Yariv Brotman
- Genetics of Metabolic Traits Group, Max Planck Institute for Molecular Plant Physiology, Potsdam 14476, Germany; Department of Life Sciences, Ben-Gurion University of the Negev, 8410501 Beer-Sheva, Israel
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13
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Shiva S, Samarakoon T, Lowe KA, Roach C, Vu HS, Colter M, Porras H, Hwang C, Roth MR, Tamura P, Li M, Schrick K, Shah J, Wang X, Wang H, Welti R. Leaf Lipid Alterations in Response to Heat Stress of Arabidopsis thaliana. PLANTS 2020; 9:plants9070845. [PMID: 32635518 PMCID: PMC7412450 DOI: 10.3390/plants9070845] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 06/30/2020] [Accepted: 07/03/2020] [Indexed: 01/19/2023]
Abstract
In response to elevated temperatures, plants alter the activities of enzymes that affect lipid composition. While it has long been known that plant leaf membrane lipids become less unsaturated in response to heat, other changes, including polygalactosylation of galactolipids, head group acylation of galactolipids, increases in phosphatidic acid and triacylglycerols, and formation of sterol glucosides and acyl sterol glucosides, have been observed more recently. In this work, by measuring lipid levels with mass spectrometry, we confirm the previously observed changes in Arabidopsis thaliana leaf lipids under three heat stress regimens. Additionally, in response to heat, increased oxidation of the fatty acyl chains of leaf galactolipids, sulfoquinovosyldiacylglycerols, and phosphatidylglycerols, and incorporation of oxidized acyl chains into acylated monogalactosyldiacylglycerols are shown. We also observed increased levels of digalactosylmonoacylglycerols and monogalactosylmonoacylglycerols. The hypothesis that a defect in sterol glycosylation would adversely affect regrowth of plants after a severe heat stress regimen was tested, but differences between wild-type and sterol glycosylation-defective plants were not detected.
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Affiliation(s)
- Sunitha Shiva
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
- Correspondence: (S.S.); (R.W.)
| | - Thilani Samarakoon
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Kaleb A. Lowe
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Charles Roach
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Hieu Sy Vu
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Madeline Colter
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Hollie Porras
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Caroline Hwang
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Mary R. Roth
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Pamela Tamura
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Maoyin Li
- Department of Biological Sciences, University of North Texas, Denton, TX 76203-5017, USA; (M.L.); (X.W.)
- Department of Biology, University of Missouri-St. Louis, St. Louis, MO 63121-4499, USA
| | - Kathrin Schrick
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
| | - Jyoti Shah
- Donald Danforth Plant Science Center, St. Louis, MO 63132, USA;
| | - Xuemin Wang
- Department of Biological Sciences, University of North Texas, Denton, TX 76203-5017, USA; (M.L.); (X.W.)
- Department of Biology, University of Missouri-St. Louis, St. Louis, MO 63121-4499, USA
| | - Haiyan Wang
- Department of Statistics, Kansas State University, Manhattan, KS 66506-0802, USA;
| | - Ruth Welti
- Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506-4901, USA; (T.S.); (K.A.L.); (C.R.); (H.S.V.); (M.C.); (H.P.); (C.H.); (M.R.R.); (P.T.); (K.S.)
- Correspondence: (S.S.); (R.W.)
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14
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Sarabia LD, Boughton BA, Rupasinghe T, Callahan DL, Hill CB, Roessner U. Comparative spatial lipidomics analysis reveals cellular lipid remodelling in different developmental zones of barley roots in response to salinity. PLANT, CELL & ENVIRONMENT 2020; 43:327-343. [PMID: 31714612 PMCID: PMC7063987 DOI: 10.1111/pce.13653] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 08/25/2019] [Accepted: 08/27/2019] [Indexed: 05/18/2023]
Abstract
Salinity-induced metabolic, ionic, and transcript modifications in plants have routinely been studied using whole plant tissues, which do not provide information on spatial tissue responses. The aim of this study was to assess the changes in the lipid profiles in a spatial manner and to quantify the changes in the elemental composition in roots of seedlings of four barley cultivars before and after a short-term salt stress. We used a combination of liquid chromatography-tandem mass spectrometry, inductively coupled plasma mass spectrometry, matrix-assisted laser desorption/ionization mass spectrometry imaging, and reverse transcription - quantitative real time polymerase chain reaction platforms to examine the molecular signatures of lipids, ions, and transcripts in three anatomically different seminal root tissues before and after salt stress. We found significant changes to the levels of major lipid classes including a decrease in the levels of lysoglycerophospholipids, ceramides, and hexosylceramides and an increase in the levels of glycerophospholipids, hydroxylated ceramides, and hexosylceramides. Our results revealed that modifications to lipid and transcript profiles in plant roots in response to a short-term salt stress may involve recycling of major lipid species, such as phosphatidylcholine, via resynthesis from glycerophosphocholine.
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Affiliation(s)
- Lenin D. Sarabia
- School of BioSciences and Metabolomics AustraliaUniversity of MelbourneParkvilleVIC3010Australia
| | | | | | - Damien L. Callahan
- School of Life and Environmental Sciences, Centre for Chemistry and Biotechnology, (Burwood Campus)Deakin University, Geelong, Australia221 Burwood HighwayBurwoodVIC3125Australia
| | - Camilla B. Hill
- School of Veterinary and Life SciencesMurdoch UniversityMurdochWA6150Australia
| | - Ute Roessner
- School of BioSciences and Metabolomics AustraliaUniversity of MelbourneParkvilleVIC3010Australia
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15
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Patton-Vogt J, de Kroon AIPM. Phospholipid turnover and acyl chain remodeling in the yeast ER. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158462. [PMID: 31146038 PMCID: PMC10716787 DOI: 10.1016/j.bbalip.2019.05.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/01/2019] [Accepted: 05/15/2019] [Indexed: 12/14/2022]
Abstract
The turnover of phospholipids plays an essential role in membrane lipid homeostasis by impacting both lipid head group and acyl chain composition. This review focusses on the degradation and acyl chain remodeling of the major phospholipid classes present in the ER membrane of the reference eukaryote Saccharomyces cerevisiae, i.e. phosphatidylcholine (PC), phosphatidylinositol (PI) and phosphatidylethanolamine (PE). Phospholipid turnover reactions are introduced, and the occurrence and important functions of phospholipid remodeling in higher eukaryotes are briefly summarized. After presenting an inventory of established mechanisms of phospholipid acyl chain exchange, current knowledge of phospholipid degradation and remodeling by phospholipases and acyltransferases localized to the yeast ER is summarized. PC is subject to the PC deacylation-reacylation remodeling pathway (PC-DRP) involving a phospholipase B, the recently identified glycerophosphocholine acyltransferase Gpc1p, and the broad specificity acyltransferase Ale1p. PI is post-synthetically enriched in C18:0 acyl chains by remodeling reactions involving Cst26p. PE may undergo turnover by the phospholipid: diacylglycerol acyltransferase Lro1p as first step in acyl chain remodeling. Clues as to the functions of phospholipid acyl chain remodeling are discussed.
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Affiliation(s)
- Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Anton I P M de Kroon
- Membrane Biochemistry & Biophysics, Bijvoet Center and Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands.
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16
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He M, Qin CX, Wang X, Ding NZ. Plant Unsaturated Fatty Acids: Biosynthesis and Regulation. FRONTIERS IN PLANT SCIENCE 2020; 11:390. [PMID: 32425958 PMCID: PMC7212373 DOI: 10.3389/fpls.2020.00390] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 03/18/2020] [Indexed: 05/11/2023]
Abstract
In most plants, major unsaturated fatty acids (UFAs) are three C18 species, namely, oleic (18:1), linoleic (18:2), and α-linolenic (18:3) acids. These simple compounds play multiple crucial roles in planta and are also important economic traits of oil crops. The enzymatic steps of C18 UFA biosynthesis have been well established. However, the associated FA/lipid trafficking between the plastid and the endoplasmic reticulum remains largely unclear, as does the regulation of the expression and activities of the involved enzymes. In this review, we will revisit the biosynthesis of C18 UFAs with an emphasis on the trafficking, and present an overview of the key enzymes and their regulation. Of particular interest is the emerging regulatory network composed of transcriptional factors and upstream signaling pathways. The review thereby provides the promise of using physical, biochemical and/or genetic means to manipulate FA composition and increase oil yield in crop improvement.
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17
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Karki N, Johnson BS, Bates PD. Metabolically Distinct Pools of Phosphatidylcholine Are Involved in Trafficking of Fatty Acids out of and into the Chloroplast for Membrane Production. THE PLANT CELL 2019; 31:2768-2788. [PMID: 31511316 PMCID: PMC6881139 DOI: 10.1105/tpc.19.00121] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 08/12/2019] [Accepted: 09/11/2019] [Indexed: 05/18/2023]
Abstract
The eukaryotic pathway of galactolipid synthesis involves fatty acid synthesis in the chloroplast, followed by assembly of phosphatidylcholine (PC) in the endoplasmic reticulum (ER), and then turnover of PC to provide a substrate for chloroplast galactolipid synthesis. However, the mechanisms and classes of lipids transported between the chloroplast and the ER are unclear. PC, PC-derived diacylglycerol, phosphatidic acid, and lyso-phosphatidylcholine (LPC) have all been implicated in ER-to-chloroplast lipid transfer. LPC transport requires lysophosphatidylcholine acyltransferase (LPCAT) activity at the chloroplast to form PC before conversion to galactolipids. However, LPCAT has also been implicated in the opposite chloroplast-to-ER trafficking of newly synthesized fatty acids through PC acyl editing. To understand the role of LPC and LPCAT in acyl trafficking we produced and analyzed the Arabidopsis (Arabidopsis thaliana) act1 lpcat1 lpcat2 triple mutant. LPCAT1 and LPCAT2 encode the major lysophospholipid acyltransferase activity of the chloroplast, and it is predominantly for incorporation of nascent fatty acids exported form the chloroplast into PC by acyl editing. In vivo acyl flux analysis revealed eukaryotic galactolipid synthesis is not impaired in act1 lpcat1 lpcat2 and uses a PC pool distinct from that of PC acyl editing. We present a model for the eukaryotic pathway with metabolically distinct pools of PC, suggesting an underlying spatial organization of PC metabolism as part of the ER-chloroplast metabolic interactions.
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Affiliation(s)
- Nischal Karki
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, Mississippi 39406
| | - Brandon S Johnson
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164
| | - Philip D Bates
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, Mississippi 39406
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164
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18
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Xu Y, Caldo KMP, Jayawardhane K, Ozga JA, Weselake RJ, Chen G. A transferase interactome that may facilitate channeling of polyunsaturated fatty acid moieties from phosphatidylcholine to triacylglycerol. J Biol Chem 2019; 294:14838-14844. [PMID: 31481466 DOI: 10.1074/jbc.ac119.010601] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 08/25/2019] [Indexed: 12/23/2022] Open
Abstract
Polyunsaturated fatty acids (PUFAs) such as α-linolenic acid (ALA, 18:3Δ9 cis ,12 cis ,15 cis ) have high nutritional and industrial values. In oilseed crops, PUFAs are synthesized on phosphatidylcholine (PC) and accumulated in triacylglycerol (TAG). Therefore, exploring the mechanisms that route PC-derived PUFA to TAG is essential for understanding and improving PUFA production. The seed oil of flax (Linum usitatissimum) is enriched in ALA, and this plant has many lipid biosynthetic enzymes that prefer ALA-containing substrates. In this study, using membrane yeast two-hybrid and bimolecular fluorescence complementation assays, we probed recombinant flax transferase enzymes, previously shown to contribute to PUFA enrichment of TAG, for physical interactions with each other under in vivo conditions. We found that diacylglycerol acyltransferases, which catalyze the final reaction in acyl-CoA-dependent TAG biosynthesis, interact with the acyl-editing enzymes phosphatidylcholine: diacylglycerol cholinephosphotransferase, and lysophosphatidylcholine acyltransferase. Physical interactions among the acyl-editing enzymes were also identified. These findings reveal the presence of an assembly of interacting transferases that may facilitate the channeling of PUFA from PC to TAG in flax and possibly also in other oleaginous plants that produce seeds enriched in PC-modified fatty acids.
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Affiliation(s)
- Yang Xu
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Kristian Mark P Caldo
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Kethmi Jayawardhane
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Jocelyn A Ozga
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Randall J Weselake
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Guanqun Chen
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
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19
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Anaokar S, Kodali R, Jonik B, Renne MF, Brouwers JFHM, Lager I, de Kroon AIPM, Patton-Vogt J. The glycerophosphocholine acyltransferase Gpc1 is part of a phosphatidylcholine (PC)-remodeling pathway that alters PC species in yeast. J Biol Chem 2018; 294:1189-1201. [PMID: 30514764 DOI: 10.1074/jbc.ra118.005232] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/27/2018] [Indexed: 12/22/2022] Open
Abstract
Phospholipase B-mediated hydrolysis of phosphatidylcholine (PC) results in the formation of free fatty acids and glycerophosphocholine (GPC) in the yeast Saccharomyces cerevisiae GPC can be reacylated by the glycerophosphocholine acyltransferase Gpc1, which produces lysophosphatidylcholine (LPC), and LPC can be converted to PC by the lysophospholipid acyltransferase Ale1. Here, we further characterized the regulation and function of this distinct PC deacylation/reacylation pathway in yeast. Through in vitro and in vivo experiments, we show that Gpc1 and Ale1 are the major cellular GPC and LPC acyltransferases, respectively. Importantly, we report that Gpc1 activity affects the PC species profile. Loss of Gpc1 decreased the levels of monounsaturated PC species and increased those of diunsaturated PC species, whereas Gpc1 overexpression had the opposite effects. Of note, Gpc1 loss did not significantly affect phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine profiles. Our results indicate that Gpc1 is involved in postsynthetic PC remodeling that produces more saturated PC species. qRT-PCR analyses revealed that GPC1 mRNA abundance is regulated coordinately with PC biosynthetic pathways. Inositol availability, which regulates several phospholipid biosynthetic genes, down-regulated GPC1 expression at the mRNA and protein levels and, as expected, decreased levels of monounsaturated PC species. Finally, loss of GPC1 decreased stationary phase viability in inositol-free medium. These results indicate that Gpc1 is part of a postsynthetic PC deacylation/reacylation remodeling pathway (PC-DRP) that alters the PC species profile, is regulated in coordination with other major lipid biosynthetic pathways, and affects yeast growth.
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Affiliation(s)
- Sanket Anaokar
- Departments of Biological Sciences, Pittsburgh, Pennsylvania 15282
| | - Ravindra Kodali
- Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282
| | - Benjamin Jonik
- Departments of Biological Sciences, Pittsburgh, Pennsylvania 15282
| | - Mike F Renne
- Department of Membrane Biochemistry & Biophysics, Bijvoet Center and Institute of Biomembranes, 3584 CH Utrecht, The Netherlands
| | - Jos F H M Brouwers
- Department of Biochemistry and Cell Biology, Institute of Biomembranes, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Ida Lager
- Department of Plant Breeding, Swedish University of Agricultural Sciences, SE-230 53 Alnarp, Sweden
| | - Anton I P M de Kroon
- Department of Membrane Biochemistry & Biophysics, Bijvoet Center and Institute of Biomembranes, 3584 CH Utrecht, The Netherlands
| | - Jana Patton-Vogt
- Departments of Biological Sciences, Pittsburgh, Pennsylvania 15282.
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20
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Xu Y, Caldo KMP, Pal-Nath D, Ozga J, Lemieux MJ, Weselake RJ, Chen G. Properties and Biotechnological Applications of Acyl-CoA:diacylglycerol Acyltransferase and Phospholipid:diacylglycerol Acyltransferase from Terrestrial Plants and Microalgae. Lipids 2018; 53:663-688. [PMID: 30252128 DOI: 10.1002/lipd.12081] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 07/23/2018] [Accepted: 07/24/2018] [Indexed: 12/14/2022]
Abstract
Triacylglycerol (TAG) is the major storage lipid in most terrestrial plants and microalgae, and has great nutritional and industrial value. Since the demand for vegetable oil is consistently increasing, numerous studies have been focused on improving the TAG content and modifying the fatty-acid compositions of plant seed oils. In addition, there is a strong research interest in establishing plant vegetative tissues and microalgae as platforms for lipid production. In higher plants and microalgae, TAG biosynthesis occurs via acyl-CoA-dependent or acyl-CoA-independent pathways. Diacylglycerol acyltransferase (DGAT) catalyzes the last and committed step in the acyl-CoA-dependent biosynthesis of TAG, which appears to represent a bottleneck in oil accumulation in some oilseed species. Membrane-bound and soluble forms of DGAT have been identified with very different amino-acid sequences and biochemical properties. Alternatively, TAG can be formed through acyl-CoA-independent pathways via the catalytic action of membrane-bound phospholipid:diacylglycerol acyltransferase (PDAT). As the enzymes catalyzing the terminal steps of TAG formation, DGAT and PDAT play crucial roles in determining the flux of carbon into seed TAG and thus have been considered as the key targets for engineering oil production. Here, we summarize the most recent knowledge on DGAT and PDAT in higher plants and microalgae, with the emphasis on their physiological roles, structural features, and regulation. The development of various metabolic engineering strategies to enhance the TAG content and alter the fatty-acid composition of TAG is also discussed.
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Affiliation(s)
- Yang Xu
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta, T6G 2P5, Canada
| | - Kristian Mark P Caldo
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta, T6G 2P5, Canada
- Department of Biochemistry, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta, T6G 2H7, Canada
| | - Dipasmita Pal-Nath
- French Associates Institute for Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion, 8499000, Israel
| | - Jocelyn Ozga
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta, T6G 2P5, Canada
| | - M Joanne Lemieux
- Department of Biochemistry, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta, T6G 2H7, Canada
| | - Randall J Weselake
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta, T6G 2P5, Canada
| | - Guanqun Chen
- Department of Agricultural, Food and Nutritional Science, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta, T6G 2P5, Canada
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21
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Substrate preferences of long-chain acyl-CoA synthetase and diacylglycerol acyltransferase contribute to enrichment of flax seed oil with α-linolenic acid. Biochem J 2018. [PMID: 29523747 DOI: 10.1042/bcj20170910] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Seed oil from flax (Linum usitatissimum) is enriched in α-linolenic acid (ALA; 18:3Δ9cis,12cis,15cis ), but the biochemical processes underlying the enrichment of flax seed oil with this polyunsaturated fatty acid are not fully elucidated. Here, a potential process involving the catalytic actions of long-chain acyl-CoA synthetase (LACS) and diacylglycerol acyltransferase (DGAT) is proposed for ALA enrichment in triacylglycerol (TAG). LACS catalyzes the ATP-dependent activation of free fatty acid to form acyl-CoA, which in turn may serve as an acyl-donor in the DGAT-catalyzed reaction leading to TAG. To test this hypothesis, flax LACS and DGAT cDNAs were functionally expressed in Saccharomyces cerevisiae strains to probe their possible involvement in the enrichment of TAG with ALA. Among the identified flax LACSs, LuLACS8A exhibited significantly enhanced specificity for ALA over oleic acid (18:1Δ9cis ) or linoleic acid (18:2Δ9cis,12cis ). Enhanced α-linolenoyl-CoA specificity was also observed in the enzymatic assay of flax DGAT2 (LuDGAT2-3), which displayed ∼20 times increased preference toward α-linolenoyl-CoA over oleoyl-CoA. Moreover, when LuLACS8A and LuDGAT2-3 were co-expressed in yeast, both in vitro and in vivo experiments indicated that the ALA-containing TAG enrichment process was operative between LuLACS8A- and LuDGAT2-3-catalyzed reactions. Overall, the results support the hypothesis that the cooperation between the reactions catalyzed by LACS8 and DGAT2 may represent a route to enrich ALA production in the flax seed oil.
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22
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Bioactivity and biotechnological production of punicic acid. Appl Microbiol Biotechnol 2018; 102:3537-3549. [DOI: 10.1007/s00253-018-8883-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 02/18/2018] [Accepted: 02/19/2018] [Indexed: 02/01/2023]
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23
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Aryal N, Lu C. A Phospholipase C-Like Protein From Ricinus communis Increases Hydroxy Fatty Acids Accumulation in Transgenic Seeds of Camelina sativa. FRONTIERS IN PLANT SCIENCE 2018; 9:1576. [PMID: 30443260 PMCID: PMC6221933 DOI: 10.3389/fpls.2018.01576] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 10/09/2018] [Indexed: 05/23/2023]
Abstract
There have been strong interests in producing unusual fatty acids in oilseed crops to provide renewable industrial feedstock. Results are so far largely disappointing since much lower amounts of such fatty acids accumulate in genetically engineered seeds than in their original natural sources. It has been suggested that the flux of unusual fatty acids through phosphatidylcholine (PC) represents a major bottleneck for high accumulation of such fatty acids in triacylglycerol (TAG). We show here that a phospholipase C-like protein (RcPLCL1) from castor bean, which accumulates nearly 90% of the hydroxylated ricinoleic acid in its seed TAG, increases the amount of hydroxy fatty acids (HFAs) when co-expresses with the fatty acid hydroxylase (RcFAH12) in transgenic seed of Camelina sativa. RcPLCL1 shows hydrolyzing activities on both PC and phosphatidylinositol substrates in our in vitro assay conditions. The PC-PLC activity of the RcPLCL1 may have increased the efficiency of HFA-PC to diacylglycerol conversion, which explains our observation of increased HFA contents in TAG concomitant with decreased HFA in the membrane lipid PC during seed development. Consequently, this may also alleviate the potential detrimental effect of HFA on germination of the engineered camelina seeds. Our results provide new knowledge that will help design effective strategies to engineer high levels of HFAs in transgenic oilseeds.
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24
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Nakamura Y. Plant Phospholipid Diversity: Emerging Functions in Metabolism and Protein-Lipid Interactions. TRENDS IN PLANT SCIENCE 2017; 22:1027-1040. [PMID: 28993119 DOI: 10.1016/j.tplants.2017.09.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 08/26/2017] [Accepted: 09/07/2017] [Indexed: 05/22/2023]
Abstract
Phospholipids are essential components of biological membranes and signal transduction cascades in plants. In recent years, plant phospholipid research was greatly advanced by the characterization of numerous mutants affected in phospholipid biosynthesis and the discovery of a number of functionally important phospholipid-binding proteins. It is now accepted that most phospholipids to some extent have regulatory functions, including those that serve as constituents of biological membranes. Phospholipids are more than an inert end product of lipid biosynthesis. This review article summarizes recent advances on phospholipid biosynthesis with a particular focus on polar head group synthesis, followed by a short overview on protein-phospholipid interactions as an emerging regulatory mechanism of phospholipid function in arabidopsis (Arabidopsis thaliana).
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Affiliation(s)
- Yuki Nakamura
- Institute of Plant and Microbial Biology, Academia Sinica, Taiwan 11529, Taiwan; http://ipmb.sinica.edu.tw/index.html/?q=node/972&language=en.
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Jasieniecka-Gazarkiewicz K, Lager I, Carlsson AS, Gutbrod K, Peisker H, Dörmann P, Stymne S, Banaś A. Acyl-CoA:Lysophosphatidylethanolamine Acyltransferase Activity Regulates Growth of Arabidopsis. PLANT PHYSIOLOGY 2017; 174:986-998. [PMID: 28408542 PMCID: PMC5462050 DOI: 10.1104/pp.17.00391] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 04/12/2017] [Indexed: 05/05/2023]
Abstract
Arabidopsis (Arabidopsis thaliana) contains two enzymes (encoded by the At1g80950 and At2g45670 genes) preferentially acylating lysophosphatidylethanolamine (LPE) with acyl-coenzyme A (CoA), designated LYSOPHOSPHATIDYLETHANOLAMINE ACYLTRANSFERASE1 (LPEAT1) and LPEAT2. The transfer DNA insertion mutant lpeat2 and the double mutant lpeat1 lpeat2 showed impaired growth, smaller leaves, shorter roots, less seed setting, and reduced lipid content per fresh weight in roots and seeds and large increases in LPE and lysophosphatidylcholine (LPC) contents in leaves. Microsomal preparations from leaves of these mutants showed around 70% decrease in acylation activity of LPE with 16:0-CoA compared with wild-type membranes, whereas the acylation with 18:1-CoA was much less affected, demonstrating that other lysophospholipid acyltransferases than the two LPEATs could acylate LPE The above-mentioned effects were less pronounced in the single lpeat1 mutant. Overexpression of either LPEAT1 or LPEAT2 under the control of the 35S promotor led to morphological changes opposite to what was seen in the transfer DNA mutants. Acyl specificity studies showed that LPEAT1 utilized 16:0-CoA at the highest rate of 11 tested acyl-CoAs, whereas LPEAT2 utilized 20:0-CoA as the best acyl donor. Both LPEATs could acylate either sn position of ether analogs of LPC The data show that the activities of LPEAT1 and LPEAT2 are, in a complementary way, involved in growth regulation in Arabidopsis. It is shown that LPEAT activity (especially LPEAT2) is essential for maintaining adequate levels of phosphatidylethanolamine, LPE, and LPC in the cells.
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Affiliation(s)
- Katarzyna Jasieniecka-Gazarkiewicz
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.)
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
| | - Ida Lager
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.)
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
| | - Anders S Carlsson
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.)
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
| | - Katharina Gutbrod
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.)
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
| | - Helga Peisker
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.)
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
| | - Peter Dörmann
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.)
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
| | - Sten Stymne
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.)
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
| | - Antoni Banaś
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-307 Gdansk, Poland (K.J.-G., A.B.);
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden (I.L., A.S.C., S.S.); and
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, 53115 Bonn, Germany (K.G., H.P., P.D.)
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Yilmaz JL, Lim ZL, Beganovic M, Breazeale S, Andre C, Stymne S, Vrinten P, Senger T. Determination of Substrate Preferences for Desaturases and Elongases for Production of Docosahexaenoic Acid from Oleic Acid in Engineered Canola. Lipids 2017; 52:207-222. [PMID: 28197856 PMCID: PMC5325871 DOI: 10.1007/s11745-017-4235-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 01/16/2017] [Indexed: 11/25/2022]
Abstract
Production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in plant seed oils has been pursued to improve availability of these omega-3 fatty acids that provide important human health benefits. Canola (Brassica napus), through the introduction of 10 enzymes, can convert oleic acid (OLA) into EPA and ultimately DHA through a pathway consisting of two elongation and five desaturation steps. Herein we present an assessment of the substrate specificity of the seven desaturases and three elongases that were introduced into canola by expressing individual proteins in yeast. In vivo feeding experiments were conducted with 14 potential fatty acid intermediates in an OLA to DHA pathway to determine the fatty acid substrate profiles for each enzyme. Membrane fractions were prepared from yeast expression strains and shown to contain active enzymes. The elongases, as expected, extended acyl-CoA substrates in the presence of malonyl-CoA. To distinguish between enzymes that desaturate CoA- and phosphatidylcholine-linked fatty acid substrates, we developed a novel in vitro method. We show that a delta-12 desaturase from Phytophthora sojae, an omega-3 desaturase from Phytophthora infestans and a delta-4 desaturase from Thraustochytrium sp., all prefer phosphatidylcholine-linked acyl substrates with comparatively low use of acyl-CoA substrates. To further validate our method, a delta-9 desaturase from Saccharomyces cerevisiae was confirmed to use acyl-CoA as substrate, but could not use phosphatidylcholine-linked substrates. The results and the assay methods presented herein will be useful in efforts to improve modeling of fatty acid metabolism and production of EPA and DHA in plants.
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Affiliation(s)
| | - Ze Long Lim
- Bioriginal Food and Science Corporation, Saskatoon, SK, S7N 0W9, Canada
| | - Mirela Beganovic
- Scandinavian Biotechnology Research (ScanBiRes) AB, 230 53, Alnarp, Sweden
| | | | - Carl Andre
- BASF Plant Science LP, Research Triangle Park, NC, 27709, USA
| | - Sten Stymne
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53, Alnarp, Sweden
| | - Patricia Vrinten
- Bioriginal Food and Science Corporation, Saskatoon, SK, S7N 0W9, Canada
| | - Toralf Senger
- BASF Plant Science LP, Research Triangle Park, NC, 27709, USA
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Głąb B, Beganovic M, Anaokar S, Hao MS, Rasmusson AG, Patton-Vogt J, Banaś A, Stymne S, Lager I. Cloning of Glycerophosphocholine Acyltransferase (GPCAT) from Fungi and Plants: A NOVEL ENZYME IN PHOSPHATIDYLCHOLINE SYNTHESIS. J Biol Chem 2016; 291:25066-25076. [PMID: 27758859 PMCID: PMC5122774 DOI: 10.1074/jbc.m116.743062] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 10/06/2016] [Indexed: 12/22/2022] Open
Abstract
Glycero-3-phosphocholine (GPC), the product of the complete deacylation of phosphatidylcholine (PC), was long thought to not be a substrate for reacylation. However, it was recently shown that cell-free extracts from yeast and plants could acylate GPC with acyl groups from acyl-CoA. By screening enzyme activities of extracts derived from a yeast knock-out collection, we were able to identify and clone the yeast gene (GPC1) encoding the enzyme, named glycerophosphocholine acyltransferase (GPCAT). By homology search, we also identified and cloned GPCAT genes from three plant species. All enzymes utilize acyl-CoA to acylate GPC, forming lyso-PC, and they show broad acyl specificities in both yeast and plants. In addition to acyl-CoA, GPCAT efficiently utilizes LPC and lysophosphatidylethanolamine as acyl donors in the acylation of GPC. GPCAT homologues were found in the major eukaryotic organism groups but not in prokaryotes or chordates. The enzyme forms its own protein family and does not contain any of the acyl binding or lipase motifs that are present in other studied acyltransferases and transacylases. In vivo labeling studies confirm a role for Gpc1p in PC biosynthesis in yeast. It is postulated that GPCATs contribute to the maintenance of PC homeostasis and also have specific functions in acyl editing of PC (e.g. in transferring acyl groups modified at the sn-2 position of PC to the sn-1 position of this molecule in plant cells).
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Affiliation(s)
- Bartosz Głąb
- From the Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-822 Gdańsk, Poland
| | - Mirela Beganovic
- the Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden
| | - Sanket Anaokar
- the Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282, and
| | - Meng-Shu Hao
- the Department of Biology, Lund University, Biology Building A, Sölvegatan 35, 223 62 Lund, Sweden
| | - Allan G Rasmusson
- the Department of Biology, Lund University, Biology Building A, Sölvegatan 35, 223 62 Lund, Sweden
| | - Jana Patton-Vogt
- the Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania 15282, and
| | - Antoni Banaś
- From the Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, 80-822 Gdańsk, Poland
| | - Sten Stymne
- the Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden
| | - Ida Lager
- the Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden,
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Lung SC, Chye ML. Deciphering the roles of acyl-CoA-binding proteins in plant cells. PROTOPLASMA 2016; 253:1177-95. [PMID: 26340904 DOI: 10.1007/s00709-015-0882-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 08/21/2015] [Indexed: 05/18/2023]
Abstract
Lipid trafficking is vital for metabolite exchange and signal communications between organelles and endomembranes. Acyl-CoA-binding proteins (ACBPs) are involved in the intracellular transport, protection, and pool formation of acyl-CoA esters, which are important intermediates and regulators in lipid metabolism and cellular signaling. In this review, we highlight recent advances in our understanding of plant ACBP families from a cellular and developmental perspective. Plant ACBPs have been extensively studied in Arabidopsis thaliana (a dicot) and to a lesser extent in Oryza sativa (a monocot). Thus far, they have been detected in the plasma membrane, vesicles, endoplasmic reticulum, Golgi apparatus, apoplast, cytosol, nuclear periphery, and peroxisomes. In combination with biochemical and molecular genetic tools, the widespread subcellular distribution of respective ACBP members has been explicitly linked to their functions in lipid metabolism during development and in response to stresses. At the cellular level, strong expression of specific ACBP homologs in specialized cells, such as embryos, stem epidermis, guard cells, male gametophytes, and phloem sap, is of relevance to their corresponding distinct roles in organ development and stress responses. Other interesting patterns in their subcellular localization and spatial expression that prompt new directions in future investigations are discussed.
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Affiliation(s)
- Shiu-Cheung Lung
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Mee-Len Chye
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.
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29
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Horn PJ, Liu J, Cocuron JC, McGlew K, Thrower NA, Larson M, Lu C, Alonso AP, Ohlrogge J. Identification of multiple lipid genes with modifications in expression and sequence associated with the evolution of hydroxy fatty acid accumulation in Physaria fendleri. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 86:322-348. [PMID: 26991237 DOI: 10.1111/tpj.13163] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 03/02/2016] [Accepted: 03/07/2016] [Indexed: 06/05/2023]
Abstract
Two Brassicaceae species, Physaria fendleri and Camelina sativa, are genetically very closely related to each other and to Arabidopsis thaliana. Physaria fendleri seeds contain over 50% hydroxy fatty acids (HFAs), while Camelina sativa and Arabidopsis do not accumulate HFAs. To better understand how plants evolved new biochemical pathways with the capacity to accumulate high levels of unusual fatty acids, transcript expression and protein sequences of developing seeds of Physaria fendleri, wild-type Camelina sativa, and Camelina sativa expressing a castor bean (Ricinus communis) hydroxylase were analyzed. A number of potential evolutionary adaptations within lipid metabolism that probably enhance HFA production and accumulation in Physaria fendleri, and, in their absence, limit accumulation in transgenic tissues were revealed. These adaptations occurred in at least 20 genes within several lipid pathways from the onset of fatty acid synthesis and its regulation to the assembly of triacylglycerols. Lipid genes of Physaria fendleri appear to have co-evolved through modulation of transcriptional abundances and alterations within protein sequences. Only a handful of genes showed evidence for sequence adaptation through gene duplication. Collectively, these evolutionary changes probably occurred to minimize deleterious effects of high HFA amounts and/or to enhance accumulation for physiological advantage. These results shed light on the evolution of pathways for novel fatty acid production in seeds, help explain some of the current limitations to accumulation of HFAs in transgenic plants, and may provide improved strategies for future engineering of their production.
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Affiliation(s)
- Patrick J Horn
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Jinjie Liu
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
| | | | - Kathleen McGlew
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Nicholas A Thrower
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
| | - Matt Larson
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
| | - Chaofu Lu
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, Montana, USA
| | - Ana P Alonso
- Department of Molecular Genetics, Ohio State University, Columbus, Ohio, USA
| | - John Ohlrogge
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
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30
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Bates PD. Understanding the control of acyl flux through the lipid metabolic network of plant oil biosynthesis. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1214-1225. [PMID: 27003249 DOI: 10.1016/j.bbalip.2016.03.021] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/10/2016] [Accepted: 03/11/2016] [Indexed: 10/22/2022]
Abstract
Plant oil biosynthesis involves a complex metabolic network with multiple subcellular compartments, parallel pathways, cycles, and pathways that have a dual function to produce essential membrane lipids and triacylglycerol. Modern molecular biology techniques provide tools to alter plant oil compositions through bioengineering, however with few exceptions the final composition of triacylglycerol cannot be predicted. One reason for limited success in oilseed bioengineering is the inadequate understanding of how to control the flux of fatty acids through various fatty acid modification, and triacylglycerol assembly pathways of the lipid metabolic network. This review focuses on the mechanisms of acyl flux through the lipid metabolic network, and highlights where uncertainty resides in our understanding of seed oil biosynthesis. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
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Affiliation(s)
- Philip D Bates
- Department of Chemistry and Biochemistry, The University of Southern Mississippi, 118 College Dr. #5043, Hattiesburg, MS 39406-0001, United States.
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31
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Allen DK. Assessing compartmentalized flux in lipid metabolism with isotopes. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1226-1242. [PMID: 27003250 DOI: 10.1016/j.bbalip.2016.03.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 03/13/2016] [Accepted: 03/14/2016] [Indexed: 12/28/2022]
Abstract
Metabolism in plants takes place across multiple cell types and within distinct organelles. The distributions equate to spatial heterogeneity; though the limited means to experimentally assess metabolism frequently involve homogenizing tissues and mixing metabolites from different locations. Most current isotope investigations of metabolism therefore lack the ability to resolve spatially distinct events. Recognition of this limitation has resulted in inspired efforts to advance metabolic flux analysis and isotopic labeling techniques. Though a number of these efforts have been applied to studies in central metabolism; recent advances in instrumentation and techniques present an untapped opportunity to make similar progress in lipid metabolism where the use of stable isotopes has been more limited. These efforts will benefit from sophisticated radiolabeling reports that continue to enrich our knowledge on lipid biosynthetic pathways and provide some direction for stable isotope experimental design and extension of MFA. Evidence for this assertion is presented through the review of several elegant stable isotope studies and by taking stock of what has been learned from radioisotope investigations when spatial aspects of metabolism were considered. The studies emphasize that glycerolipid production occurs across several locations with assembly of lipids in the ER or plastid, fatty acid biosynthesis occurring in the plastid, and the generation of acetyl-CoA and glycerol-3-phosphate taking place at multiple sites. Considering metabolism in this context underscores the cellular and subcellular organization that is important to enhanced production of glycerolipids in plants. An attempt is made to unify salient features from a number of reports into a diagrammatic model of lipid metabolism and propose where stable isotope labeling experiments and further flux analysis may help address questions in the field. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
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Affiliation(s)
- Doug K Allen
- United States Department of Agriculture, Agricultural Research Service, 975 North Warson Road, St. Louis, MO 63132, United States; Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, United States.
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Jasieniecka-Gazarkiewicz K, Demski K, Lager I, Stymne S, Banaś A. Possible Role of Different Yeast and Plant Lysophospholipid:Acyl-CoA Acyltransferases (LPLATs) in Acyl Remodelling of Phospholipids. Lipids 2015; 51:15-23. [PMID: 26643989 PMCID: PMC4700060 DOI: 10.1007/s11745-015-4102-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 11/12/2015] [Indexed: 12/02/2022]
Abstract
Recent results have suggested that plant lysophosphatidylcholine:acyl-coenzyme A acyltransferases (LPCATs) can operate in reverse in vivo and thereby catalyse an acyl exchange between the acyl-coenzyme A (CoA) pool and the phosphatidylcholine. We have investigated the abilities of Arabidopsis AtLPCAT2, Arabidopsis lysophosphatidylethanolamine acyltransferase (LPEAT2), S. cerevisiae lysophospholipid acyltransferase (Ale1) and S. cerevisiae lysophosphatidic acid acyltransferase (SLC1) to acylate lysoPtdCho, lysoPtdEtn and lysoPtdOH and act reversibly on the products of the acylation; the PtdCho, PtdEtn and PtdOH. The tested LPLATs were expressed in an S. cervisiaeale1 strain and enzyme activities were assessed in assays using microsomal preparations of the different transformants. The results show that, despite high activity towards lysoPtdCho, lysoPtdEtn and lysoPtdOH by the ALE1, its capacities to operate reversibly on the products of the acylation were very low. Slc1 readily acylated lysoPtdOH, lysoPtdCho and lysoPtdEtn but showed no reversibility towards PtdCho, very little reversibility towards PtdEtn and very high reversibility towards PtdOH. LPEAT2 showed the highest levels of reversibility towards PtdCho and PtdEtn of all LPLATs tested but low ability to operate reversibly on PtdOH. AtLPCAT2 showed good reversible activity towards PtdCho and PtdEtn and very low reversibility towards PtdOH. Thus, it appears that some of the LPLATs have developed properties that, to a much higher degree than other LPLATs, promote the reverse reaction during the same assay conditions and with the same phospholipid. The results also show that the capacity of reversibility can be specific for a particular phospholipid, albeit the lysophospholipid derivatives of other phospholipids serve as good acyl acceptors for the forward reaction of the enzyme.
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Affiliation(s)
| | - Kamil Demski
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki 24, 80-822, Gdańsk, Poland
| | - Ida Lager
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53, Alnarp, Sweden
| | - Sten Stymne
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53, Alnarp, Sweden
| | - Antoni Banaś
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki 24, 80-822, Gdańsk, Poland.
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Chen G, Woodfield HK, Pan X, Harwood JL, Weselake RJ. Acyl-Trafficking During Plant Oil Accumulation. Lipids 2015; 50:1057-68. [DOI: 10.1007/s11745-015-4069-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 08/28/2015] [Indexed: 11/25/2022]
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Aktas M, Narberhaus F. Unconventional membrane lipid biosynthesis inXanthomonas campestris. Environ Microbiol 2015; 17:3116-24. [DOI: 10.1111/1462-2920.12956] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/03/2015] [Accepted: 06/14/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Meriyem Aktas
- Microbial Biology; Ruhr University Bochum; Universitätsstrasse 150, NDEF 06/783 Bochum D-44780 Germany
| | - Franz Narberhaus
- Microbial Biology; Ruhr University Bochum; Universitätsstrasse 150, NDEF 06/783 Bochum D-44780 Germany
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35
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Liu Y, Wang G, Wang X. Role of aminoalcoholphosphotransferases 1 and 2 in phospholipid homeostasis in Arabidopsis. THE PLANT CELL 2015; 27:1512-28. [PMID: 25944098 PMCID: PMC4456648 DOI: 10.1105/tpc.15.00180] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 04/14/2015] [Indexed: 05/02/2023]
Abstract
Aminoalcoholphosphotransferase (AAPT) catalyzes the synthesis of phosphatidylcholine (PC) and phosphotidylethanolamine (PE), which are the most prevalent membrane phospholipids in all eukaryotic cells. Here, we show that suppression of AAPTs results in extensive membrane phospholipid remodeling in Arabidopsis thaliana. Double knockout (KO) mutants that are hemizygous for either aapt1 or aapt2 display impaired pollen and seed development, leading to embryotic lethality of the double KO plants, whereas aapt1 or aapt2 single KO plants show no overt phenotypic alterations. The growth rate and seed yield of AAPT RNA interference (RNAi) plants are greatly reduced. Lipid profiling shows decreased total galactolipid and phospholipid content in aapt1-containing mutants, including aapt1, aapt1/aapt1 aapt2/AAPT2, aapt1/AAPT1 aapt2/aapt2, and AAPT RNAi plants. The level of PC in leaves was unchanged, whereas that of PE was reduced in all AAPT-deficient plants, except aapt2 KO. However, the acyl species of PC was altered, with increased levels of C34 species and decreased C36 species. Conversely, the levels of PE and phosphatidylinositol were decreased in C34 species. In seeds, all AAPT-deficient plants, including aapt2 KO, displayed a decrease in PE. The data show that AAPT1 and AAPT2 are essential to plant vegetative growth and reproduction and have overlapping functions but that AAPT1 contributes more than AAPT2 to PC production in vegetative tissues. The opposite changes in molecular species between PC and PE and unchanged PC level indicate the existence of additional pathways that maintain homeostatic levels of PC, which are crucial for the survival and proper development of plants.
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Affiliation(s)
- Yu Liu
- Department of Biology, University of Missouri, St. Louis, Missouri 63121 Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Geliang Wang
- Department of Biology, University of Missouri, St. Louis, Missouri 63121 Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Xuemin Wang
- Department of Biology, University of Missouri, St. Louis, Missouri 63121 Donald Danforth Plant Science Center, St. Louis, Missouri 63132
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Allen DK, Bates PD, Tjellström H. Tracking the metabolic pulse of plant lipid production with isotopic labeling and flux analyses: Past, present and future. Prog Lipid Res 2015; 58:97-120. [PMID: 25773881 DOI: 10.1016/j.plipres.2015.02.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 01/30/2015] [Accepted: 02/11/2015] [Indexed: 11/25/2022]
Abstract
Metabolism is comprised of networks of chemical transformations, organized into integrated biochemical pathways that are the basis of cellular operation, and function to sustain life. Metabolism, and thus life, is not static. The rate of metabolites transitioning through biochemical pathways (i.e., flux) determines cellular phenotypes, and is constantly changing in response to genetic or environmental perturbations. Each change evokes a response in metabolic pathway flow, and the quantification of fluxes under varied conditions helps to elucidate major and minor routes, and regulatory aspects of metabolism. To measure fluxes requires experimental methods that assess the movements and transformations of metabolites without creating artifacts. Isotopic labeling fills this role and is a long-standing experimental approach to identify pathways and quantify their metabolic relevance in different tissues or under different conditions. The application of labeling techniques to plant science is however far from reaching it potential. In light of advances in genetics and molecular biology that provide a means to alter metabolism, and given recent improvements in instrumentation, computational tools and available isotopes, the use of isotopic labeling to probe metabolism is becoming more and more powerful. We review the principal analytical methods for isotopic labeling with a focus on seminal studies of pathways and fluxes in lipid metabolism and carbon partitioning through central metabolism. Central carbon metabolic steps are directly linked to lipid production by serving to generate the precursors for fatty acid biosynthesis and lipid assembly. Additionally some of the ideas for labeling techniques that may be most applicable for lipid metabolism in the future were originally developed to investigate other aspects of central metabolism. We conclude by describing recent advances that will play an important future role in quantifying flux and metabolic operation in plant tissues.
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Affiliation(s)
- Doug K Allen
- United States Department of Agriculture, Agricultural Research Service, 975 North Warson Road, St. Louis, MO 63132, United States; Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, United States.
| | - Philip D Bates
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, MS 39406, United States
| | - Henrik Tjellström
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, United States; Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, United States
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