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Zemlianski V, Marešová A, Princová J, Holič R, Häsler R, Ramos Del Río MJ, Lhoste L, Zarechyntsava M, Převorovský M. Nitrogen availability is important for preventing catastrophic mitosis in fission yeast. J Cell Sci 2024; 137:jcs262196. [PMID: 38780300 DOI: 10.1242/jcs.262196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024] Open
Abstract
Mitosis is a crucial stage in the cell cycle, controlled by a vast network of regulators responding to multiple internal and external factors. The fission yeast Schizosaccharomyces pombe demonstrates catastrophic mitotic phenotypes due to mutations or drug treatments. One of the factors provoking catastrophic mitosis is a disturbed lipid metabolism, resulting from, for example, mutations in the acetyl-CoA/biotin carboxylase (cut6), fatty acid synthase (fas2, also known as lsd1) or transcriptional regulator of lipid metabolism (cbf11) genes, as well as treatment with inhibitors of fatty acid synthesis. It has been previously shown that mitotic fidelity in lipid metabolism mutants can be partially rescued by ammonium chloride supplementation. In this study, we demonstrate that mitotic fidelity can be improved by multiple nitrogen sources. Moreover, this improvement is not limited to lipid metabolism disturbances but also applies to a number of unrelated mitotic mutants. Interestingly, the partial rescue is not achieved by restoring the lipid metabolism state, but rather indirectly. Our results highlight a novel role for nitrogen availability in mitotic fidelity.
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Affiliation(s)
- Viacheslav Zemlianski
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, 128 00 Prague 2, Czechia
| | - Anna Marešová
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, 128 00 Prague 2, Czechia
| | - Jarmila Princová
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, 128 00 Prague 2, Czechia
| | - Roman Holič
- Centre of Biosciences SAS, Institute of Animal Biochemistry and Genetics, Dúbravská cesta 9, 840 05 Bratislava, Slovak Republic
| | - Robert Häsler
- Center for Inflammatory Skin Diseases, Department of Dermatology and Allergy, University Hospital Schleswig-Holstein, Campus Kiel, Rosalind-Franklin-Straße 9, 24105 Kiel, Germany
| | - Manuel José Ramos Del Río
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, 128 00 Prague 2, Czechia
| | - Laurane Lhoste
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, 128 00 Prague 2, Czechia
| | - Maryia Zarechyntsava
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, 128 00 Prague 2, Czechia
| | - Martin Převorovský
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, 128 00 Prague 2, Czechia
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2
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Cook R, Froehlich JE, Yang Y, Korkmaz I, Kramer DM, Benning C. Chloroplast phosphatases LPPγ and LPPε1 facilitate conversion of extraplastidic phospholipids to galactolipids. PLANT PHYSIOLOGY 2024; 195:1506-1520. [PMID: 38401529 DOI: 10.1093/plphys/kiae100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/08/2024] [Accepted: 01/25/2024] [Indexed: 02/26/2024]
Abstract
Galactolipids comprise the majority of chloroplast membranes in plants, and their biosynthesis requires dephosphorylation of phosphatidic acid at the chloroplast envelope membranes. In Arabidopsis (Arabidopsis thaliana), the lipid phosphate phosphatases LPPγ, LPPε1, and LPPε2 have been previously implicated in chloroplast lipid assembly, with LPPγ being essential, as null mutants were reported to exhibit embryo lethality. Here, we show that lppγ mutants are in fact viable and that LPPγ, LPPε1, and LPPε2 do not appear to have central roles in the plastid pathway of membrane lipid biosynthesis. Redundant LPPγ and LPPε1 activity at the outer envelope membrane is important for plant development, and the respective lppγ lppε1 double mutant exhibits reduced flux through the ER pathway of galactolipid synthesis. While LPPε2 is imported and associated with interior chloroplast membranes, its role remains elusive and does not include basal nor phosphate limitation-induced biosynthesis of glycolipids. The specific physiological roles of LPPγ, LPPε1, and LPPε2 are yet to be uncovered, as does the identity of the phosphatidic acid phosphatase required for plastid galactolipid biosynthesis.
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Affiliation(s)
- Ron Cook
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
| | - John E Froehlich
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Yang Yang
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
| | - Ilayda Korkmaz
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - David M Kramer
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Christoph Benning
- DOE-Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA
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3
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Shimojo M, Nakamura M, Kitaura G, Ihara Y, Shimizu S, Hori K, Iwai M, Ohta H, Ishizaki K, Shimojima M. Phosphatidic acid phosphohydrolase modulates glycerolipid synthesis in Marchantia polymorpha and is crucial for growth under both nutrient-replete and -deficient conditions. PLANTA 2023; 258:92. [PMID: 37792042 PMCID: PMC10550880 DOI: 10.1007/s00425-023-04247-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/18/2023] [Indexed: 10/05/2023]
Abstract
MAIN CONCLUSION The phosphatidic acid phosphohydrolase of Marchantia polymorpha modulates plastid glycolipid synthesis through the ER pathway and is essential for normal plant development regardless of nutrient availability. Membrane lipid remodeling is one of the strategies plant cells use to secure inorganic phosphate (Pi) for plant growth, but many aspects of the molecular mechanism and its regulation remain unclear. Here we analyzed membrane lipid remodeling using a non-vascular plant, Marchantia polymorpha. The lipid composition and fatty acid profile during Pi starvation in M. polymorpha revealed a decrease in phospholipids and an increase in both galactolipids and betaine lipids. In Arabidopsis thaliana, phosphatidic acid phosphohydrolase (PAH) is involved in phospholipid degradation and is crucial for tolerance to both Pi and nitrogen starvation. We produced two M. polymorpha PAH (MpPAH) knockout mutants (Mppah-1 and Mppah-2) and found that, unlike Arabidopsis mutants, Mppah impaired plant growth with shorter rhizoids compared with wild-type plants even under nutrient-replete conditions. Mutation of MpPAH did not significantly affect the mole percent of each glycerolipid among total membrane glycerolipids from whole plants under both Pi-replete and Pi-deficient conditions. However, the fatty acid composition of monogalactosyldiacylglycerol indicated that the amount of plastid glycolipids produced through the endoplasmic reticulum pathway was suppressed in Mppah mutants. Phospholipids accumulated in the mutants under N starvation. These results reveal that MpPAH modulates plastid glycolipid synthesis through the endoplasmic reticulum pathway more so than what has been observed for Arabidopsis PAH; moreover, unlike Arabidopsis, MpPAH is crucial for M. polymorpha growth regardless of nutrient availability.
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Affiliation(s)
- Misao Shimojo
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Masashi Nakamura
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Ginga Kitaura
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
| | - Yuta Ihara
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Shinsuke Shimizu
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Koichi Hori
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Masako Iwai
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Hiroyuki Ohta
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | | | - Mie Shimojima
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan.
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4
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Zhao Y, Dong Q, Geng Y, Ma C, Shao Q. Dynamic Regulation of Lipid Droplet Biogenesis in Plant Cells and Proteins Involved in the Process. Int J Mol Sci 2023; 24:ijms24087476. [PMID: 37108639 PMCID: PMC10138601 DOI: 10.3390/ijms24087476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
Lipid droplets (LDs) are ubiquitous, dynamic organelles found in almost all organisms, including animals, protists, plants and prokaryotes. The cell biology of LDs, especially biogenesis, has attracted increasing attention in recent decades because of their important role in cellular lipid metabolism and other newly identified processes. Emerging evidence suggests that LD biogenesis is a highly coordinated and stepwise process in animals and yeasts, occurring at specific sites of the endoplasmic reticulum (ER) that are defined by both evolutionarily conserved and organism- and cell type-specific LD lipids and proteins. In plants, understanding of the mechanistic details of LD formation is elusive as many questions remain. In some ways LD biogenesis differs between plants and animals. Several homologous proteins involved in the regulation of animal LD formation in plants have been identified. We try to describe how these proteins are synthesized, transported to the ER and specifically targeted to LD, and how these proteins participate in the regulation of LD biogenesis. Here, we review current work on the molecular processes that control LD formation in plant cells and highlight the proteins that govern this process, hoping to provide useful clues for future research.
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Affiliation(s)
- Yiwu Zhao
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Qingdi Dong
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Yuhu Geng
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Changle Ma
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Qun Shao
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
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5
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Garaiova M, Hua Q, Holic R. Heterologous Production of Calendic Acid Naturally Found in Calendula officinalis by Recombinant Fission Yeast. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:3842-3851. [PMID: 36795330 DOI: 10.1021/acs.jafc.2c08967] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Calendic acid (CA) is a conjugated fatty acid with anti-cancer properties that is widely present in seed oil of Calendula officinalis. Using the co-expression of C. officinalis fatty acid conjugases (CoFADX-1 or CoFADX-2) and Punica granatum fatty acid desaturase (PgFAD2), we metabolically engineered the synthesis of CA in the yeast Schizosaccharomyces pombe without the need for linoleic acid (LA) supplementation. The highest CA titer and achieved accumulation were 4.4 mg/L and 3.7 mg/g of DCW in PgFAD2 + CoFADX-2 recombinant strain cultivated at 16 °C for 72 h, respectively. Further analyses revealed the accumulation of CA in free fatty acids (FFA) and downregulation of the lcf1 gene encoding long-chain fatty acyl-CoA synthetase. The developed recombinant yeast system represents an important tool for the future identification of the essential components of the channeling machinery to produce CA as a high-value conjugated fatty acid at an industrial level.
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Affiliation(s)
- Martina Garaiova
- Institute of Animal Biochemistry and Genetics, Centre of Biosciences, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 84005, Slovakia
| | - Qiang Hua
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Roman Holic
- Institute of Animal Biochemistry and Genetics, Centre of Biosciences, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 84005, Slovakia
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6
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Sun D, Quan W, Wang D, Cui J, Wang T, Lin M, Wang Y, Wang N, Dong Y, Li X, Liu W, Wang F. Genome-Wide Identification and Expression Analysis of Fatty Acid Desaturase ( FAD) Genes in Camelina sativa (L.) Crantz. Int J Mol Sci 2022; 23:ijms232314550. [PMID: 36498878 PMCID: PMC9738755 DOI: 10.3390/ijms232314550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/18/2022] [Accepted: 11/17/2022] [Indexed: 11/24/2022] Open
Abstract
Camelina sativa (L.) Crantz is an indispensable oilseed crop, and its seeds contain many unsaturated fatty acids. FAD (fatty acid desaturase) regulates the synthesis of unsaturated fatty acids. In this research, we performed CsFAD gene family analysis and identified 24 CsFAD genes in Camelina, which were unevenly distributed on 14 of the 19 total chromosomes. Phylogenetic analysis showed that CsFAD includes four subfamilies, supported by the conserved structures and motifs of CsFAD genes. In addition, we investigated the expression patterns of the FAD family in the different tissues of Camelina. We found that CsFAD family genes were all expressed in the stem, and CsFAD2-2 was highly expressed in the early stage of seed development. Moreover, during low temperature (4 °C) stress, we identified that the expression level of CsFAD2-2 significantly changed. By observing the transient expression of CsFAD2-2 in Arabidopsis protoplasts, we found that CsFAD2-2 was located on the nucleus. Through the detection and analysis of fatty acids, we prove that CsFAD2-2 is involved in the synthesis of linolenic acid (C18:3). In conclusion, we identified CsFAD2-2 through the phylogenetic analysis of the CsFAD gene family and further determined the fatty acid content to find that CsFAD2-2 is involved in fatty acid synthesis in Camelina.
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7
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Chen G, Harwood JL, Lemieux MJ, Stone SJ, Weselake RJ. Acyl-CoA:diacylglycerol acyltransferase: Properties, physiological roles, metabolic engineering and intentional control. Prog Lipid Res 2022; 88:101181. [PMID: 35820474 DOI: 10.1016/j.plipres.2022.101181] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/31/2022] [Accepted: 07/04/2022] [Indexed: 12/15/2022]
Abstract
Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) catalyzes the last reaction in the acyl-CoA-dependent biosynthesis of triacylglycerol (TAG). DGAT activity resides mainly in membrane-bound DGAT1 and DGAT2 in eukaryotes and bifunctional wax ester synthase-diacylglycerol acyltransferase (WSD) in bacteria, which are all membrane-bound proteins but exhibit no sequence homology to each other. Recent studies also identified other DGAT enzymes such as the soluble DGAT3 and diacylglycerol acetyltransferase (EaDAcT), as well as enzymes with DGAT activities including defective in cuticular ridges (DCR) and steryl and phytyl ester synthases (PESs). This review comprehensively discusses research advances on DGATs in prokaryotes and eukaryotes with a focus on their biochemical properties, physiological roles, and biotechnological and therapeutic applications. The review begins with a discussion of DGAT assay methods, followed by a systematic discussion of TAG biosynthesis and the properties and physiological role of DGATs. Thereafter, the review discusses the three-dimensional structure and insights into mechanism of action of human DGAT1, and the modeled DGAT1 from Brassica napus. The review then examines metabolic engineering strategies involving manipulation of DGAT, followed by a discussion of its therapeutic applications. DGAT in relation to improvement of livestock traits is also discussed along with DGATs in various other eukaryotic organisms.
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Affiliation(s)
- Guanqun Chen
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada.
| | - John L Harwood
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - M Joanne Lemieux
- Department of Biochemistry, University of Alberta, Membrane Protein Disease Research Group, Edmonton T6G 2H7, Canada
| | - Scot J Stone
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
| | - Randall J Weselake
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada
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8
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Interactions between plant lipid-binding proteins and their ligands. Prog Lipid Res 2022; 86:101156. [DOI: 10.1016/j.plipres.2022.101156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 10/05/2021] [Accepted: 01/14/2022] [Indexed: 01/11/2023]
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9
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Mechanisms of lipid droplet biogenesis. Biochem J 2019; 476:1929-1942. [DOI: 10.1042/bcj20180021] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/11/2019] [Accepted: 06/13/2019] [Indexed: 12/28/2022]
Abstract
Abstract
Lipid droplets (LDs) are organelles that compartmentalize nonbilayer-forming lipids in the aqueous cytoplasm of cells. They are ubiquitous in most organisms, including in animals, protists, plants and microorganisms. In eukaryotes, LDs are believed to be derived by a budding and scission process from the surface of the endoplasmic reticulum, and this occurs concomitantly with the accumulation of neutral lipids, most often triacylglycerols and steryl esters. Overall, the mechanisms underlying LD biogenesis are difficult to generalize, in part because of the involvement of different sets of both evolutionarily conserved and organism-specific LD-packaging proteins. Here, we briefly compare and contrast these proteins and the allied processes responsible for LD biogenesis in cells of animals, yeasts and plants.
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10
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Yan YY, Yang B, Lan XY, Li XY, Xu FL. Cadmium accumulation capacity and resistance strategies of a cadmium-hypertolerant fern - Microsorum fortunei. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 649:1209-1223. [PMID: 30308892 DOI: 10.1016/j.scitotenv.2018.08.281] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 08/18/2018] [Accepted: 08/21/2018] [Indexed: 06/08/2023]
Abstract
Microsorum fortunei (M. fortunei), a close relative to the cadmium (Cd) hyperaccumulator Microsorum pteropus, is an epiphytic Polypodiaceae fern with strong antioxidant activity. The Cd-accumulation capacities and Cd-resistance mechanisms of M. fortunei were analyzed in this study by measuring metal contents (Cd, Fe, Mg, Ca, Zn, Mn, K and Na) and chlorophyll fluorescence parameters (Fv/Fm, qN, qP, Y(II), Y(NPQ) and Y(NO)) and by performing an RNA-sequencing analysis. M. fortunei could accumulate up to 2249.10 μg/g DW Cd in roots under a 15-day 1000 μmol/L Cd treatment, with little Cd translocated into the leaves (maximum 138.26 μg/g DW). The M. fortunei leaves could maintain their normal physiological functions with no phytosynthesis damage and few changes in metal contents or differentially expressed genes. M. fortunei roots showed a decrease in Zn concentration, with potential Cd-tolerance mechanisms such as heavy metal transporters, vesicle trafficking and fusion proteins, antioxidant systems, and primary metabolites like plant hormones, revealed by differentially expressed functional genes. In conclusion, M. fortunei may serve as a potential cadmium-hypertolerant fern that sequesters and detoxifies most cadmium in the roots, with a minimum root-to-shoot Cd translocation to guarantee the physiological functions in the more vulnerable leaves.
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Affiliation(s)
- Yun-Yun Yan
- MOE Laboratory for Earth Surface Processes, College of Urban & Environmental Sciences, Peking University, Beijing 100871, China
| | - Bin Yang
- MOE Laboratory for Earth Surface Processes, College of Urban & Environmental Sciences, Peking University, Beijing 100871, China
| | - Xin-Yu Lan
- MOE Laboratory for Earth Surface Processes, College of Urban & Environmental Sciences, Peking University, Beijing 100871, China
| | - Xin-Yuan Li
- MOE Laboratory for Earth Surface Processes, College of Urban & Environmental Sciences, Peking University, Beijing 100871, China
| | - Fu-Liu Xu
- MOE Laboratory for Earth Surface Processes, College of Urban & Environmental Sciences, Peking University, Beijing 100871, China.
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11
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Maraschin FDS, Kulcheski FR, Segatto ALA, Trenz TS, Barrientos-Diaz O, Margis-Pinheiro M, Margis R, Turchetto-Zolet AC. Enzymes of glycerol-3-phosphate pathway in triacylglycerol synthesis in plants: Function, biotechnological application and evolution. Prog Lipid Res 2019; 73:46-64. [DOI: 10.1016/j.plipres.2018.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/01/2018] [Accepted: 12/01/2018] [Indexed: 01/30/2023]
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12
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Gayral M, Fanuel M, Rogniaux H, Dalgalarrondo M, Elmorjani K, Bakan B, Marion D. The Spatiotemporal Deposition of Lysophosphatidylcholine Within Starch Granules of Maize Endosperm and its Relationships to the Expression of Genes Involved in Endoplasmic Reticulum-Amyloplast Lipid Trafficking and Galactolipid Synthesis. PLANT & CELL PHYSIOLOGY 2019; 60:139-151. [PMID: 30295886 DOI: 10.1093/pcp/pcy198] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 09/28/2018] [Indexed: 05/19/2023]
Abstract
The presence of lipids within starch granules is specific to cereal endosperm starches. These starch lipids are composed of lysophospholipids, especially lysophosphatidylcholine (LysoPC) and free fatty acids that strongly impact the assembly and properties of cereal starches. However, the molecular mechanisms associated with this specific lipid routing have never been investigated. In this study, matrix-assisted laser desorption ionization mass spectrometry imaging revealed decreasing gradients in starch LysoPC concentrations from the periphery to the center of developing maize endosperms. This spatiotemporal deposition of starch LysoPC was similar to that previously observed for endoplasmic reticulum (ER)-synthesized storage proteins, i.e. zeins, suggesting that LysoPC might originate in the ER, as already reported for chloroplasts. Furthermore, a decrease of the palmitate concentration of amyloplast galactolipids was observed during endosperm development, correlated with the preferential trapping of palmitoyl-LysoPC by starch carbohydrates, suggesting a link between LysoPC and galactolipid synthesis. Using microarray, the homologous genes of the Arabidopsis ER-chloroplast lipid trafficking and galactolipid synthesis pathways were also expressed in maize endosperm. These strong similarities suggest that the encoded enzymes and transporters are adapted to managing the differences between chloroplast and amyloplast lipid homeostasis. Altogether, our results led us to propose a model where ER-amyloplast lipid trafficking directs the LysoPC towards one of two routes, the first towards the stroma and starch granules and the other towards galactolipid synthesis.
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Affiliation(s)
- Mathieu Gayral
- INRA, Biopolymers, Interactions, Assemblies Research Unit, La Géraudière, Nantes Cedex 3, France
| | - Mathieu Fanuel
- INRA, Biopolymers, Interactions, Assemblies Research Unit, La Géraudière, Nantes Cedex 3, France
| | - Hélène Rogniaux
- INRA, Biopolymers, Interactions, Assemblies Research Unit, La Géraudière, Nantes Cedex 3, France
| | - Michèle Dalgalarrondo
- INRA, Biopolymers, Interactions, Assemblies Research Unit, La Géraudière, Nantes Cedex 3, France
| | - Khalil Elmorjani
- INRA, Biopolymers, Interactions, Assemblies Research Unit, La Géraudière, Nantes Cedex 3, France
| | - Bénédicte Bakan
- INRA, Biopolymers, Interactions, Assemblies Research Unit, La Géraudière, Nantes Cedex 3, France
| | - Didier Marion
- INRA, Biopolymers, Interactions, Assemblies Research Unit, La Géraudière, Nantes Cedex 3, France
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13
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Zhang Z, He G, Han GS, Zhang J, Catanzaro N, Diaz A, Wu Z, Carman GM, Xie L, Wang X. Host Pah1p phosphatidate phosphatase limits viral replication by regulating phospholipid synthesis. PLoS Pathog 2018; 14:e1006988. [PMID: 29649282 PMCID: PMC5916857 DOI: 10.1371/journal.ppat.1006988] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 04/24/2018] [Accepted: 03/24/2018] [Indexed: 11/20/2022] Open
Abstract
Replication of positive-strand RNA viruses [(+)RNA viruses] takes place in membrane-bound viral replication complexes (VRCs). Formation of VRCs requires virus-mediated manipulation of cellular lipid synthesis. Here, we report significantly enhanced brome mosaic virus (BMV) replication and much improved cell growth in yeast cells lacking PAH1 (pah1Δ), the sole yeast ortholog of human LIPIN genes. PAH1 encodes Pah1p (phosphatidic acid phosphohydrolase), which converts phosphatidate (PA) to diacylglycerol that is subsequently used for the synthesis of the storage lipid triacylglycerol. Inactivation of Pah1p leads to altered lipid composition, including high levels of PA, total phospholipids, ergosterol ester, and free fatty acids, as well as expansion of the nuclear membrane. In pah1Δ cells, BMV replication protein 1a and double-stranded RNA localized to the extended nuclear membrane, there was a significant increase in the number of VRCs formed, and BMV genomic replication increased by 2-fold compared to wild-type cells. In another yeast mutant that lacks both PAH1 and DGK1 (encodes diacylglycerol kinase converting diacylglycerol to PA), which has a normal nuclear membrane but maintains similar lipid compositional changes as in pah1Δ cells, BMV replicated as efficiently as in pah1Δ cells, suggesting that the altered lipid composition was responsible for the enhanced BMV replication. We further showed that increased levels of total phospholipids play an important role because the enhanced BMV replication required active synthesis of phosphatidylcholine, the major membrane phospholipid. Moreover, overexpression of a phosphatidylcholine synthesis gene (CHO2) promoted BMV replication. Conversely, overexpression of PAH1 or plant PAH1 orthologs inhibited BMV replication in yeast or Nicotiana benthamiana plants. Competing with its host for limited resources, BMV inhibited host growth, which was markedly alleviated in pah1Δ cells. Our work suggests that Pah1p promotes storage lipid synthesis and thus represses phospholipid synthesis, which in turn restricts both viral replication and cell growth during viral infection.
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Affiliation(s)
- Zhenlu Zhang
- Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, P. R. China
- Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA, United States of America
| | - Guijuan He
- Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, P. R. China
- Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA, United States of America
| | - Gil-Soo Han
- Department of Food Science and the Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition, and Health, Rutgers University, New Brunswick, NJ, United States of America
| | - Jiantao Zhang
- Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA, United States of America
| | - Nicholas Catanzaro
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States of America
| | - Arturo Diaz
- Department of Biology, La Sierra University, Riverside, VA, United States of America
| | - Zujian Wu
- Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, P. R. China
| | - George M. Carman
- Department of Food Science and the Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition, and Health, Rutgers University, New Brunswick, NJ, United States of America
| | - Lianhui Xie
- Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, P. R. China
| | - Xiaofeng Wang
- Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA, United States of America
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14
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Pillai AN, Shukla S, Rahaman A. An evolutionarily conserved phosphatidate phosphatase maintains lipid droplet number and endoplasmic reticulum morphology but not nuclear morphology. Biol Open 2017; 6:1629-1643. [PMID: 28954739 PMCID: PMC5703613 DOI: 10.1242/bio.028233] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Phosphatidic acid phosphatases are involved in the biosynthesis of phospholipids and triacylglycerol, and also act as transcriptional regulators. Studies to ascertain their role in lipid metabolism and membrane biogenesis are restricted to Opisthokonta and Archaeplastida. Here, we report the role of phosphatidate phosphatase (PAH) in Tetrahymena thermophila, belonging to the Alveolata clade. We identified two PAH homologs in Tetrahymena, TtPAH1 and TtPAH2 Loss of function of TtPAH1 results in reduced lipid droplet number and an increase in endoplasmic reticulum (ER) content. It also results in more ER sheet structure as compared to wild-type Tetrahymena Surprisingly, we did not observe a visible defect in the nuclear morphology of the ΔTtpah1 mutant. TtPAH1 rescued all known defects in the yeast pah1Δ strain and is conserved functionally between Tetrahymena and yeast. The homologous gene derived from Trypanosoma also rescued the defects of the yeast pah1Δ strain. Our results indicate that PAH, previously known to be conserved among Opisthokonts, is also present in a set of distant lineages. Thus, a phosphatase cascade is evolutionarily conserved and is functionally interchangeable across eukaryotic lineages.
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Affiliation(s)
- Anoop Narayana Pillai
- School of Biological Sciences, National Institute of Science Education and Research (NISER)-Bhubaneswar, HBNI, P.O. Jatni, Khurda 752050, Odisha, India
| | - Sushmita Shukla
- School of Biological Sciences, National Institute of Science Education and Research (NISER)-Bhubaneswar, HBNI, P.O. Jatni, Khurda 752050, Odisha, India
| | - Abdur Rahaman
- School of Biological Sciences, National Institute of Science Education and Research (NISER)-Bhubaneswar, HBNI, P.O. Jatni, Khurda 752050, Odisha, India
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15
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Garaiova M, Mietkiewska E, Weselake RJ, Holic R. Metabolic engineering of Schizosaccharomyces pombe to produce punicic acid, a conjugated fatty acid with nutraceutic properties. Appl Microbiol Biotechnol 2017; 101:7913-7922. [DOI: 10.1007/s00253-017-8498-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Revised: 08/09/2017] [Accepted: 08/23/2017] [Indexed: 02/01/2023]
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16
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Craddock CP, Adams N, Kroon JT, Bryant FM, Hussey PJ, Kurup S, Eastmond PJ. Cyclin-dependent kinase activity enhances phosphatidylcholine biosynthesis in Arabidopsis by repressing phosphatidic acid phosphohydrolase activity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 89:3-14. [PMID: 27595588 PMCID: PMC5299491 DOI: 10.1111/tpj.13321] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 08/22/2016] [Accepted: 08/24/2016] [Indexed: 05/21/2023]
Abstract
Coordination of endomembrane biogenesis with cell cycle progression is considered to be important in maintaining cell function during growth and development. We previously showed that the disruption of PHOSPHATIDIC ACID PHOSPHOHYDROLASE (PAH) activity in Arabidopsis thaliana stimulates biosynthesis of the major phospholipid phosphatidylcholine (PC) and causes expansion of the endoplasmic reticulum. Here we show that PC biosynthesis is repressed by disruption of the core cell cycle regulator CYCLIN-DEPENDENT KINASE A;1 (CDKA;1) and that this repression is reliant on PAH. Furthermore, we show that cyclin-dependent kinases (CDKs) phosphorylate PAH1 at serine 162, which reduces both its activity and membrane association. Expression of a CDK-insensitive version of PAH1 with a serine 162 to alanine substitution represses PC biosynthesis and also reduces the rate of cell division in early leaf development. Together our findings reveal a physiologically important mechanism that couples the rate of phospholipid biosynthesis and endomembrane biogenesis to cell cycle progression in Arabidopsis.
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Affiliation(s)
- Christian P. Craddock
- School of Life SciencesUniversity of WarwickCoventryCV4 7ALUK
- Present address: Center for Plant Cell BiologyDepartment of Botany and Plant SciencesUniversity of CaliforniaRiverside92521USA
| | - Nicolette Adams
- School of Life SciencesUniversity of WarwickCoventryCV4 7ALUK
- Present address: Centre for Proteomic and Genomic ResearchUpper LevelSt Peter's MallCorner Anzio and Main Road ObservatoryCape Town7925South Africa
| | - Johan T.M. Kroon
- School of Biological and Biomedical SciencesDurham UniversityDurhamDH1 3LEUK
| | - Fiona M. Bryant
- Department of Plant Biology and Crop ScienceRothamsted ResearchHarpendenHertfordshireAL5 2JQUK
- Present address: School of Biological and Biomedical SciencesDurham UniversityDurhamDH1 3LEUK
| | - Patrick J. Hussey
- School of Biological and Biomedical SciencesDurham UniversityDurhamDH1 3LEUK
| | - Smita Kurup
- Department of Plant Biology and Crop ScienceRothamsted ResearchHarpendenHertfordshireAL5 2JQUK
| | - Peter J. Eastmond
- Department of Plant Biology and Crop ScienceRothamsted ResearchHarpendenHertfordshireAL5 2JQUK
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17
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Botella C, Jouhet J, Block MA. Importance of phosphatidylcholine on the chloroplast surface. Prog Lipid Res 2017; 65:12-23. [DOI: 10.1016/j.plipres.2016.11.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/04/2016] [Accepted: 11/06/2016] [Indexed: 12/11/2022]
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18
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Singer SD, Chen G, Mietkiewska E, Tomasi P, Jayawardhane K, Dyer JM, Weselake RJ. Arabidopsis GPAT9 contributes to synthesis of intracellular glycerolipids but not surface lipids. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:4627-38. [PMID: 27325892 PMCID: PMC4973736 DOI: 10.1093/jxb/erw242] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
GLYCEROL-3-PHOSPHATE ACYLTRANSFERASE (GPAT) genes encode enzymes involved in glycerolipid biosynthesis in plants. Ten GPAT homologues have been identified in Arabidopsis. GPATs 4-8 have been shown to be involved in the production of extracellular lipid barrier polyesters. Recently, GPAT9 was reported to be essential for triacylglycerol (TAG) biosynthesis in developing Arabidopsis seeds. The enzymatic properties and possible functions of GPAT9 in surface lipid, polar lipid and TAG biosynthesis in non-seed organs, however, have not been investigated. Here we show that Arabidopsis GPAT9 exhibits sn-1 acyltransferase activity with high specificity for acyl-coenzyme A, thus providing further evidence that this GPAT is involved in storage lipid biosynthesis. We also confirm a role for GPAT9 in seed oil biosynthesis and further demonstrate that GPAT9 contributes to the biosynthesis of both polar lipids and TAG in developing leaves, as well as lipid droplet production in developing pollen grains. Conversely, alteration of constitutive GPAT9 expression had no obvious effects on surface lipid biosynthesis. Taken together, these studies expand our understanding of GPAT9 function to include modulation of several different intracellular glycerolipid pools in plant cells.
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Affiliation(s)
- Stacy D Singer
- Agricultural Lipid Biotechnology Program, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Guanqun Chen
- Agricultural Lipid Biotechnology Program, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Elzbieta Mietkiewska
- Agricultural Lipid Biotechnology Program, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - Pernell Tomasi
- USDA-ARS, US Arid-Land Agricultural Research Center, 21881 North Cardon Lane, Maricopa, AZ 85138, USA
| | - Kethmi Jayawardhane
- Agricultural Lipid Biotechnology Program, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | - John M Dyer
- USDA-ARS, US Arid-Land Agricultural Research Center, 21881 North Cardon Lane, Maricopa, AZ 85138, USA
| | - Randall J Weselake
- Agricultural Lipid Biotechnology Program, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
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19
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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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20
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Abdullah HM, Akbari P, Paulose B, Schnell D, Qi W, Park Y, Pareek A, Dhankher OP. Transcriptome profiling of Camelina sativa to identify genes involved in triacylglycerol biosynthesis and accumulation in the developing seeds. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:136. [PMID: 27382413 PMCID: PMC4932711 DOI: 10.1186/s13068-016-0555-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 06/23/2016] [Indexed: 05/20/2023]
Abstract
BACKGROUND Camelina sativa is an emerging dedicated oilseed crop designed for biofuel and biodiesel applications as well as a source for edible and general-purpose oils. Such valuable oilseed crop is subjected to plant breeding programs and is suggested for large-scale production of better seed and oil quality. To accomplish this objective and to further enhance its oil content, a better understanding of lipid metabolism at the molecular level in this plant is critical. Here, we applied tissue transcriptomics and lipid composition analysis to identify and profile the genes and gene networks associated with triacylglycerol (TAG) biosynthesis, and to investigate how those genes are interacting to determine the quantity and quality of Camelina oil during seed development. RESULTS Our Camelina transcriptome data analysis revealed an approximate of 57,854 and 57,973 genes actively expressing in developing seeds (RPKM ≥ 0.1) at 10-15 (Cs-14) and 16-21 (Cs-21) days after flowering (DAF), respectively. Of these, 7932 genes showed temporal and differential gene expression during the seed development (log2 fold change ≥1.5 or ≤-1.5; P ≤ 0.05). The differentially expressed genes (DEGs) were annotated and were found to be involved in distinct functional categories and metabolic pathways. Furthermore, performing quantitative real-time PCR for selected candidate genes associated with TAG biosynthesis validated RNA-seq data. Our results showed strong positive correlations between the expression abundance measured using both qPCR and RNA-Seq technologies. Furthermore, the analysis of fatty-acid content and composition revealed major changes throughout seed development, with the amount of oil accumulate rapidly at early mid seed development stages (from 16-28 DAF onwards), while no important changes were observed in the fatty-acid profile between seeds at 28 DAF and mature seeds. CONCLUSIONS This study is highly useful for understanding the regulation of TAG biosynthesis and identifying the rate-limiting steps in TAG pathways at seed development stages, providing a precise selection of candidate genes for developing Camelina varieties with improved seed and oil yields.
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Affiliation(s)
- Hesham M. Abdullah
- />Stockbridge School of Agriculture, University of Massachusetts Amherst, Amherst, MA 01003 USA
- />Biotechnology Department, Faculty of Agriculture, Al-Azhar University, Cairo, 11651 Egypt
| | - Parisa Akbari
- />Stockbridge School of Agriculture, University of Massachusetts Amherst, Amherst, MA 01003 USA
| | - Bibin Paulose
- />Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Danny Schnell
- />Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Weipeng Qi
- />Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003 USA
| | - Yeonhwa Park
- />Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003 USA
| | - Ashwani Pareek
- />Stress Physiology and Molecular Biology Laboratory, School of Life Science, Jawaharlal Nehru University, New Delhi, 100067 India
| | - Om Parkash Dhankher
- />Stockbridge School of Agriculture, University of Massachusetts Amherst, Amherst, MA 01003 USA
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21
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Nakamura Y. Function of polar glycerolipids in flower development in Arabidopsis thaliana. Prog Lipid Res 2015; 60:17-29. [DOI: 10.1016/j.plipres.2015.09.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 09/22/2015] [Indexed: 11/28/2022]
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22
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Wickramarathna AD, Siloto RMP, Mietkiewska E, Singer SD, Pan X, Weselake RJ. Heterologous expression of flax PHOSPHOLIPID:DIACYLGLYCEROL CHOLINEPHOSPHOTRANSFERASE (PDCT) increases polyunsaturated fatty acid content in yeast and Arabidopsis seeds. BMC Biotechnol 2015; 15:63. [PMID: 26123542 PMCID: PMC4486708 DOI: 10.1186/s12896-015-0156-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/28/2015] [Indexed: 12/28/2022] Open
Abstract
Background Flax (Linum usitatissimum L.) is an agriculturally important crop with seed oil enriched in α-linolenic acid (18:3 cisΔ9, 12, 15; ALA). This polyunsaturated fatty acid (PUFA) is the major determinant for the quality of flax seed oil in food, nutraceuticals and industrial applications. The recently identified enzyme: phosphatidylcholine diacylglycerol cholinephosphotransferase (PDCT), catalyzes the interconversion between phosphatidylcholine (PC) and diacylglycerol (DAG), and has been shown to play an important role in PUFA accumulation in Arabidopsis thaliana seeds. Methods Two flax PDCT genes were identified using homology-based approach. Results In this study, we describe the isolation and characterization of two PDCT genes from flax (LuPDCT1 and LuPDCT2) with very high nucleotide sequence identity (97%) whose deduced amino acid sequences exhibited approximately 55% identity with that of A. thaliana PDCT (AtROD1). The genes encoded functionally active enzymes that were strongly expressed in developing embryos. Complementation studies with the A. thaliana rod1 mutant demonstrated that the flax PDCTs were capable of restoring PUFA levels in planta. Furthermore, PUFA levels increased in Saccharomyces cerevisiae when the flax PDCTs were co-expressed with FATTY ACID DESATURASES (FADs), FAD2 and FAD3, while seed-specific expression of LuPDCT1 and LuPDCT2 in A. thaliana resulted in 16.4% and 19.7% increases in C18-PUFAs, respectively, with a concomitant decrease in the proportion of oleic acid (18:1cisΔ9; OA). Conclusions The two novel PDCT homologs from flax are capable of increasing C18-PUFA levels substantially in metabolically engineered yeast and transgenic A. thaliana seeds. These flax PDCT proteins appear to play an important dual role in the determination of PUFA content by efficiently channelling monounsaturated FAs into PC for desaturation and moving the resulting PUFAs out of PC for subsequent use in TAG synthesis. These results indicate that flax PDCTs would be useful for bioengineering of oil crops to increase PUFA levels for applications in human food and nutritional supplements, animal feed and industrial bioproducts. Electronic supplementary material The online version of this article (doi:10.1186/s12896-015-0156-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Aruna D Wickramarathna
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
| | - Rodrigo M P Siloto
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
| | - Elzbieta Mietkiewska
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
| | - Stacy D Singer
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
| | - Xue Pan
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
| | - Randall J Weselake
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
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23
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Craddock CP, Adams N, Bryant FM, Kurup S, Eastmond PJ. PHOSPHATIDIC ACID PHOSPHOHYDROLASE Regulates Phosphatidylcholine Biosynthesis in Arabidopsis by Phosphatidic Acid-Mediated Activation of CTP:PHOSPHOCHOLINE CYTIDYLYLTRANSFERASE Activity. THE PLANT CELL 2015; 27:1251-64. [PMID: 25862304 PMCID: PMC4558698 DOI: 10.1105/tpc.15.00037] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 03/19/2015] [Indexed: 05/04/2023]
Abstract
Regulation of membrane lipid biosynthesis is critical for cell function. We previously reported that disruption of PHOSPHATIDIC ACID PHOSPHOHYDROLASE1 (PAH1) and PAH2 stimulates net phosphatidylcholine (PC) biosynthesis and proliferation of the endoplasmic reticulum (ER) in Arabidopsis thaliana. Here, we show that this response is caused specifically by a reduction in the catalytic activity of the protein and positively correlates with an accumulation of its substrate, phosphatidic acid (PA). The accumulation of PC in pah1 pah2 is suppressed by disruption of CTP:PHOSPHOCHOLINE CYTIDYLYLTRANSFERASE1 (CCT1), which encodes a key enzyme in the nucleotide pathway for PC biosynthesis. The activity of recombinant CCT1 is stimulated by lipid vesicles containing PA. Truncation of CCT1, to remove the predicted C-terminal amphipathic lipid binding domain, produced a constitutively active enzyme. Overexpression of native CCT1 in Arabidopsis has no significant effect on PC biosynthesis or ER morphology, but overexpression of the truncated constitutively active version largely replicates the pah1 pah2 phenotype. Our data establish that membrane homeostasis is regulated by lipid composition in Arabidopsis and reveal a mechanism through which the abundance of PA, mediated by PAH activity, modulates CCT activity to govern PC content.
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Affiliation(s)
- Christian P Craddock
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Nicolette Adams
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Fiona M Bryant
- Department of Plant Biology and Crop Science, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Smita Kurup
- Department of Plant Biology and Crop Science, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Peter J Eastmond
- Department of Plant Biology and Crop Science, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
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Mietkiewska E, Miles R, Wickramarathna A, Sahibollah AF, Greer MS, Chen G, Weselake RJ. Combined transgenic expression of Punica granatum conjugase (FADX) and FAD2 desaturase in high linoleic acid Arabidopsis thaliana mutant leads to increased accumulation of punicic acid. PLANTA 2014; 240:575-583. [PMID: 25000918 DOI: 10.1007/s00425-014-2109-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 06/17/2014] [Indexed: 06/03/2023]
Abstract
Arabidopsis was engineered to produce 21.2 % punicic acid in the seed oil. Possible molecular factors limiting further accumulation of the conjugated fatty acid were investigated. Punicic acid (18:3Δ(9cis,11trans,13cis) ) is a conjugated linolenic acid isomer and is a main component of Punica granatum (pomegranate) seed oil. Medical studies have shown that punicic acid is a nutraceutical with anti-cancer and anti-obesity properties. It has been previously demonstrated that the conjugated double bonds in punicic acid are produced via the catalytic action of fatty acid conjugase (FADX), which is a homolog of the oleate desaturase. This enzyme catalyzes the conversion of the Δ(12)-double bond of linoleic acid (18:2Δ(9cis,12cis) ) into conjugated Δ(11trans) and Δ(13cis) -double bonds. Previous attempts to produce punicic acid in transgenic Arabidopsis thaliana seeds overexpressing P. granatum FADX resulted in a limited accumulation of punicic acid of up to 4.4 %, accompanied by increased accumulation of oleic acid (18:1∆(9cis) ), suggesting that production of punicic acid in some way inhibits the activity of oleate desaturase (Iwabuchi et al. 2003). In the current study, we applied a new strategy to enhance the production of punicic acid in a high linoleic acid A. thaliana fad3/fae1 mutant background using the combined expression of P. granatum FADX and FAD2. This approach led to the accumulation of punicic acid at the level of 21 % of total fatty acids and restored the natural proportion of oleic acid observed in the A. thaliana fad3/fae1 mutant. In addition, we provide new insights into the high oleate phenotype and describe factors limiting the production of punicic acid in genetically engineered plants.
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Affiliation(s)
- Elzbieta Mietkiewska
- Alberta Innovates Phytola Centre, Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Agriculture/Forestry Centre, Edmonton, AB, T6G 2P5, Canada
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25
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Chuang C, Barajas D, Qin J, Nagy PD. Inactivation of the host lipin gene accelerates RNA virus replication through viral exploitation of the expanded endoplasmic reticulum membrane. PLoS Pathog 2014; 10:e1003944. [PMID: 24586157 PMCID: PMC3930575 DOI: 10.1371/journal.ppat.1003944] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 01/09/2014] [Indexed: 01/27/2023] Open
Abstract
RNA viruses take advantage of cellular resources, such as membranes and lipids, to assemble viral replicase complexes (VRCs) that drive viral replication. The host lipins (phosphatidate phosphatases) are particularly interesting because these proteins play key roles in cellular decisions about membrane biogenesis versus lipid storage. Therefore, we examined the relationship between host lipins and tombusviruses, based on yeast model host. We show that deletion of PAH1 (phosphatidic acid phosphohydrolase), which is the single yeast homolog of the lipin gene family of phosphatidate phosphatases, whose inactivation is responsible for proliferation and expansion of the endoplasmic reticulum (ER) membrane, facilitates robust RNA virus replication in yeast. We document increased tombusvirus replicase activity in pah1Δ yeast due to the efficient assembly of VRCs. We show that the ER membranes generated in pah1Δ yeast is efficiently subverted by this RNA virus, thus emphasizing the connection between host lipins and RNA viruses. Thus, instead of utilizing the peroxisomal membranes as observed in wt yeast and plants, TBSV readily switches to the vastly expanded ER membranes in lipin-deficient cells to build VRCs and support increased level of viral replication. Over-expression of the Arabidopsis Pah2p in Nicotiana benthamiana decreased tombusvirus accumulation, validating that our findings are also relevant in a plant host. Over-expression of AtPah2p also inhibited the ER-based replication of another plant RNA virus, suggesting that the role of lipins in RNA virus replication might include several more eukaryotic viruses.
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Affiliation(s)
- Chingkai Chuang
- Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Daniel Barajas
- Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Jun Qin
- Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, United States of America
| | - Peter D. Nagy
- Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, United States of America
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26
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Kim S, Kedan A, Marom M, Gavert N, Keinan O, Selitrennik M, Laufman O, Lev S. The phosphatidylinositol-transfer protein Nir2 binds phosphatidic acid and positively regulates phosphoinositide signalling. EMBO Rep 2013; 14:891-9. [PMID: 23897088 DOI: 10.1038/embor.2013.113] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 07/11/2013] [Accepted: 07/11/2013] [Indexed: 11/09/2022] Open
Abstract
Phosphatidic acid (PA) and phosphoinositides are metabolically interconverted lipid second messengers that have central roles in many growth factor (GF)-stimulated signalling pathways. Yet, little is known about the mechanisms that coordinate their production and downstream signalling. Here we show that the phosphatidylinositol (PI)-transfer protein Nir2 translocates from the Golgi complex to the plasma membrane in response to GF stimulation. This translocation is triggered by PA formation and is mediated by its C-terminal region that binds PA in vitro. We further show that depletion of Nir2 substantially reduces the PI(4,5)P2 levels at the plasma membrane and concomitantly GF-stimulated PI(3,4,5)P3 production. Finally, we show that Nir2 positively regulates the MAPK and PI3K/AKT pathways. We propose that Nir2 through its PA-binding capability and PI-transfer activity can couple PA to phosphoinositide signalling, and possibly coordinates their local lipid metabolism and downstream signalling.
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Affiliation(s)
- SoHui Kim
- Molecular Cell Biology Department, Weizmann Institute of Science, Rehovot 76100, Israel
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27
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Phillips SM, Dubery IA, van Heerden H. Molecular characterisation of two homoeologous elicitor-responsive lipin genes in cotton. Mol Genet Genomics 2013; 288:519-33. [PMID: 23897433 DOI: 10.1007/s00438-013-0770-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 07/04/2013] [Indexed: 11/24/2022]
Abstract
The identification and molecular characterisation of two lipin-like gene copies (GhLIPN) in cotton, Gossypium hirsutum, an allotetraploid derived from two progenitor diploid Gossypium species, is described. Sequence analyses of the GhLIPN copies, designated GhLIPN-1 and -2, revealed that they contain 11 exons, separated by ten introns. They each have a 2,643 bp open reading frame that encodes 880 aa proteins, and share a 97.7 and 95.5 % sequence similarity at the translated nucleotide and amino acid level, respectively. The GhLIPN genes have a distinct domain architecture consisting of an archetypical N-terminal lipin domain, followed by a haloacid dehalogenase (HAD) domain towards the C-terminus. A Southern blot did not distinguish between the two gene copies, which suggests that they may be homoeologs rather than paralogs. GhLIPN-2 is more similar to a homoeologous sequence from G. raimondii, representing the ancestral D-genome, compared to GhLIPN-1 that matches G. herbaceum and that represents the A-genome. Our data indicate that GhLIPN-1 and GhLIPN-2 are homoeologs that derive from the A- and the D-diploid genomes, respectively. The promoter sequences of GhLIPN-1 and -2 differ by 56 %, as a result of multiple indels. In silico analysis of the promoter regions revealed that both genes contain numerous putative defence-related and elicitor-responsive cis-elements that support a role for GhLIPN in defence responses. Relative quantification real-time PCR confirmed the up-regulation in response to a cell-wall-derived V. dahliae elicitor, which supported the association of GhLIPN with defence signalling. The results add a new dimension to the proposed roles of lipins in plants by suggesting that lipins may have a role in defence signalling.
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Affiliation(s)
- Sonia M Phillips
- Department of Biochemistry, University of Johannesburg, Kingsway Campus, P.O. Box 524, Auckland Park, 2006, South Africa
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Pan X, Siloto RMP, Wickramarathna AD, Mietkiewska E, Weselake RJ. Identification of a pair of phospholipid:diacylglycerol acyltransferases from developing flax (Linum usitatissimum L.) seed catalyzing the selective production of trilinolenin. J Biol Chem 2013; 288:24173-88. [PMID: 23824186 DOI: 10.1074/jbc.m113.475699] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The oil from flax (Linum usitatissimum L.) has high amounts of α-linolenic acid (ALA; 18:3(cis)(Δ9,12,15)) and is one of the richest sources of omega-3 polyunsaturated fatty acids (ω-3-PUFAs). To produce ∼57% ALA in triacylglycerol (TAG), it is likely that flax contains enzymes that can efficiently transfer ALA to TAG. To test this hypothesis, we conducted a systematic characterization of TAG-synthesizing enzymes from flax. We identified several genes encoding acyl-CoA:diacylglycerol acyltransferases (DGATs) and phospholipid:diacylglycerol acyltransferases (PDATs) from the flax genome database. Due to recent genome duplication, duplicated gene pairs have been identified for all genes except DGAT2-2. Analysis of gene expression indicated that two DGAT1, two DGAT2, and four PDAT genes were preferentially expressed in flax embryos. Yeast functional analysis showed that DGAT1, DGAT2, and two PDAT enzymes restored TAG synthesis when produced recombinantly in yeast H1246 strain. The activity of particular PDAT enzymes (LuPDAT1 and LuPDAT2) was stimulated by the presence of ALA. Further seed-specific expression of flax genes in Arabidopsis thaliana indicated that DGAT1, PDAT1, and PDAT2 had significant effects on seed oil phenotype. Overall, this study indicated the existence of unique PDAT enzymes from flax that are able to preferentially catalyze the synthesis of TAG containing ALA acyl moieties. The identified LuPDATs may have practical applications for increasing the accumulation of ALA and other polyunsaturated fatty acids in oilseeds for food and industrial applications.
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Affiliation(s)
- Xue Pan
- Department of Agricultural, Food, and Nutritional Science, Agricultural Lipid Biotechnology Program, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
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Siniossoglou S. Phospholipid metabolism and nuclear function: Roles of the lipin family of phosphatidic acid phosphatases. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:575-81. [DOI: 10.1016/j.bbalip.2012.09.014] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 09/19/2012] [Accepted: 09/24/2012] [Indexed: 01/22/2023]
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Abstract
Phosphatidic acid phosphatase (PAP; EC 3.1.3.4) catalyzes the dephosphorylation of phosphatidic acid (PA) to produce diacylglycerol (DAG) and inorganic phosphate. In seed plants, PA plays pivotal roles both as a precursor to membrane lipids and as a signaling molecule. As more information on the roles of PAP in plants becomes available and the importance of PAP is revealed, protocols for assaying plant PAP activity are of interest to an increasing audience. This chapter describes procedures to assay plant PAP activity that are based on recent publications.
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Affiliation(s)
- Yuki Nakamura
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
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Nakamura Y. Phosphate starvation and membrane lipid remodeling in seed plants. Prog Lipid Res 2012; 52:43-50. [PMID: 22954597 DOI: 10.1016/j.plipres.2012.07.002] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Revised: 06/25/2012] [Accepted: 07/02/2012] [Indexed: 01/07/2023]
Abstract
Phosphate is an essential, yet scarce, nutrient that seed plants need to maintain viability. Phosphate-starved plants utilize their membrane phospholipids as a major source for internal phosphate supply by replacing phospholipids in their membranes with the non-phosphorus galactolipid, digalactosyldiacylglycerol. This membrane lipid remodeling has drawn much attention as a model of metabolic switching from phospholipids to the galactolipid. In the past decade, a considerable effort has been devoted to unraveling the molecular biology of this phenomenon. This review thus aims to summarize recent achievements with a focus on metabolic pathways during lipid remodeling.
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Affiliation(s)
- Yuki Nakamura
- Institute of Plant and Microbial Biology, Academia Sinica, 128 Sec. 2 Academia Rd., Nankang, Taipei 11529, Taiwan.
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Kok BPC, Venkatraman G, Capatos D, Brindley DN. Unlike two peas in a pod: lipid phosphate phosphatases and phosphatidate phosphatases. Chem Rev 2012; 112:5121-46. [PMID: 22742522 DOI: 10.1021/cr200433m] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bernard P C Kok
- Signal Transduction Research Group, Department of Biochemistry, School of Translational Medicine, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
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Chapman KD, Dyer JM, Mullen RT. Biogenesis and functions of lipid droplets in plants: Thematic Review Series: Lipid Droplet Synthesis and Metabolism: from Yeast to Man. J Lipid Res 2012; 53:215-26. [PMID: 22045929 PMCID: PMC3269164 DOI: 10.1194/jlr.r021436] [Citation(s) in RCA: 245] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 10/31/2011] [Indexed: 12/22/2022] Open
Abstract
The compartmentation of neutral lipids in plants is mostly associated with seed tissues, where triacylglycerols (TAGs) stored within lipid droplets (LDs) serve as an essential physiological energy and carbon reserve during postgerminative growth. However, some nonseed tissues, such as leaves, flowers and fruits, also synthesize and store TAGs, yet relatively little is known about the formation or function of LDs in these tissues. Characterization of LD-associated proteins, such as oleosins, caleosins, and sterol dehydrogenases (steroleosins), has revealed surprising features of LD function in plants, including stress responses, hormone signaling pathways, and various aspects of plant growth and development. Although oleosin and caleosin proteins are specific to plants, LD-associated sterol dehydrogenases also are present in mammals, and in both plants and mammals these enzymes have been shown to be important in (steroid) hormone metabolism and signaling. In addition, several other proteins known to be important in LD biogenesis in yeasts and mammals are conserved in plants, suggesting that at least some aspects of LD biogenesis and/or function are evolutionarily conserved.
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Affiliation(s)
- Kent D. Chapman
- Department of Biological Sciences, Center for Plant Lipid Research, University of North Texas, Denton, TX
| | - John M. Dyer
- USDA-ARS, US Arid-Land Agricultural Research Center, Maricopa, AZ
| | - Robert T. Mullen
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
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Chen G, Greer MS, Lager I, Yilmaz JL, Mietkiewska E, Carlsson AS, Stymne S, Weselake RJ. Identification and characterization of an LCAT-like Arabidopsis thaliana gene encoding a novel phospholipase A. FEBS Lett 2012; 586:373-7. [PMID: 22245677 DOI: 10.1016/j.febslet.2011.12.034] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 12/14/2011] [Accepted: 12/28/2011] [Indexed: 11/29/2022]
Abstract
A previously uncharacterized Arabidopsis lecithin:cholesterol acyltransferase (LCAT) family gene (At4g19860) was functionally expressed in yeast, where it was demonstrated to encode a novel cytosolic and calcium-independent phospholipase A with preferences for the sn-2 position. This enzyme shows optimal activity at pH 5.0, exhibits a headgroup specificity for phosphatidylcholine>phosphatidic acid>phosphatidylethanolamine>phosphatidylglycerol>phosphatidylserine and has an acyl chain specificity for oleoyl>linoleoyl>ricinoleoyl. The expression of AtLCAT-PLA inhibited yeast cell growth and fatty acid accumulation. AtLCAT-PLA transcript in Arabidopsis was detected at high levels in roots and siliques.
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Affiliation(s)
- Guanqun Chen
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
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Merchant SS, Kropat J, Liu B, Shaw J, Warakanont J. TAG, you're it! Chlamydomonas as a reference organism for understanding algal triacylglycerol accumulation. Curr Opin Biotechnol 2011; 23:352-63. [PMID: 22209109 DOI: 10.1016/j.copbio.2011.12.001] [Citation(s) in RCA: 194] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Revised: 12/04/2011] [Accepted: 12/07/2011] [Indexed: 10/14/2022]
Abstract
Photosynthetic organisms are responsible for converting sunlight into organic matter, and they are therefore seen as a resource for the renewable fuel industry. Ethanol and esterified fatty acids (biodiesel) are the most common fuel products derived from these photosynthetic organisms. The potential of algae as producers of biodiesel precursor (or triacylglycerols (TAGs)) has yet to be realized because of the limited knowledge of the underlying biochemistry, cell biology and genetics. Well-characterized pathways from fungi and land plants have been used to identify algal homologs of key enzymes in TAG synthesis, including diacylglcyerol acyltransferases, phospholipid diacylglycerol acyltransferase and phosphatidate phosphatases. Many laboratories have adopted Chlamydomonas reinhardtii as a reference organism for discovery of algal-specific adaptations of TAG metabolism. Stressed Chlamydomonas cells, grown either photoautotrophically or photoheterotrophically, accumulate TAG in plastid and cytoplasmic lipid bodies, reaching 46-65% of dry weight in starch accumulation (sta) mutants. State of the art genomic technologies including expression profiling and proteomics have identified new proteins, including key components of lipid droplets, candidate regulators and lipid/TAG degrading activities. By analogy with crop plants, it is expected that advances in algal breeding and genome engineering may facilitate realizing the potential in algae.
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Affiliation(s)
- Sabeeha S Merchant
- Institute for Genomics and Proteomics and Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095, United States.
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Chapman KD, Ohlrogge JB. Compartmentation of triacylglycerol accumulation in plants. J Biol Chem 2011; 287:2288-94. [PMID: 22090025 DOI: 10.1074/jbc.r111.290072] [Citation(s) in RCA: 290] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Triacylglycerols from plants, familiar to most people as vegetable oils, supply 25% of dietary calories to the developed world and are increasingly a source for renewable biomaterials and fuels. Demand for vegetable oils will double by 2030, which can be met only by increased oil production. Triacylglycerol synthesis is accomplished through the coordinate action of multiple pathways in multiple subcellular compartments. Recent information has revealed an underappreciated complexity in pathways for synthesis and accumulation of this important energy-rich class of molecules.
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Affiliation(s)
- Kent D Chapman
- Department of Biological Sciences, Center for Plant Lipid Research, University of North Texas, Denton, Texas 76203-5017, USA.
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