101
|
Hu XD, Pan BZ, Fu Q, Niu L, Chen MS, Xu ZF. De novo transcriptome assembly of the eight major organs of Sacha Inchi (Plukenetia volubilis) and the identification of genes involved in α-linolenic acid metabolism. BMC Genomics 2018; 19:380. [PMID: 29788925 PMCID: PMC5964912 DOI: 10.1186/s12864-018-4774-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 05/09/2018] [Indexed: 12/12/2022] Open
Abstract
Background Sacha Inchi (Plukenetia volubilis L.), which belongs to the Euphorbiaceae, has been considered a new potential oil crop because of its high content of polyunsaturated fatty acids in its seed oil. The seed oil especially contains high amounts of α-linolenic acid (ALA), which is useful for the prevention of various diseases. However, little is known about the genetic information and genome sequence of Sacha Inchi, which has largely hindered functional genomics and molecular breeding studies. Results In this study, a de novo transcriptome assembly based on transcripts sequenced in eight major organs, including roots, stems, shoot apexes, mature leaves, male flowers, female flowers, fruits, and seeds of Sacha Inchi was performed, resulting in a set of 124,750 non-redundant putative transcripts having an average length of 851 bp and an N50 value of 1909 bp. Organ-specific unigenes analysis revealed that the most organ-specific transcripts are found in female flowers (2244 unigenes), whereas a relatively small amount of unigenes are detected to be expressed specifically in other organs with the least in stems (24 unigenes). A total of 42,987 simple sequence repeats (SSRs) were detected, which will contribute to the marker assisted selection breeding of Sacha Inchi. We analyzed expression of genes related to the α-linolenic acid metabolism based on the de novo assembly and annotation transcriptome in Sacha Inchi. It appears that Sacha Inchi accumulates high level of ALA in seeds by strong expression of biosynthesis-related genes and weak expression of degradation-related genes. In particular, the up-regulation of FAD3 and FAD7 is consistent with high level of ALA in seeds of Sacha Inchi compared with in other organs. Meanwhile, several transcription factors (ABI3, LEC1 and FUS3) may regulate key genes involved in oil accumulation in seeds of Sacha Inchi. Conclusions The transcriptome of major organs of Sacha Inchi has been sequenced and de novo assembled, which will expand the genetic information for functional genomic studies of Sacha Inchi. In addition, the identification of candidate genes involved in ALA metabolism will provide useful resources for the genetic improvement of Sacha Inchi and the metabolic engineering of ALA biosynthesis in other plants. Electronic supplementary material The online version of this article (10.1186/s12864-018-4774-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Xiao-Di Hu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bang-Zhen Pan
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China
| | - Qiantang Fu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China
| | - Longjian Niu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China
| | - Mao-Sheng Chen
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China
| | - Zeng-Fu Xu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China.
| |
Collapse
|
102
|
Yu X, Cahoon RE, Horn PJ, Shi H, Prakash RR, Cai Y, Hearney M, Chapman KD, Cahoon EB, Schwender J, Shanklin J. Identification of bottlenecks in the accumulation of cyclic fatty acids in camelina seed oil. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:926-938. [PMID: 28929610 PMCID: PMC5866947 DOI: 10.1111/pbi.12839] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/01/2017] [Accepted: 09/14/2017] [Indexed: 05/20/2023]
Abstract
Modified fatty acids (mFA) have diverse uses; for example, cyclopropane fatty acids (CPA) are feedstocks for producing coatings, lubricants, plastics and cosmetics. The expression of mFA-producing enzymes in crop and model plants generally results in lower levels of mFA accumulation than in their natural-occurring source plants. Thus, to further our understanding of metabolic bottlenecks that limit mFA accumulation, we generated transgenic Camelina sativa lines co-expressing Escherichia coli cyclopropane synthase (EcCPS) and Sterculia foetida lysophosphatidic acid acyltransferase (SfLPAT). In contrast to transgenic CPA-accumulating Arabidopsis, CPA accumulation in camelina caused only minor changes in seed weight, germination rate, oil accumulation and seedling development. CPA accumulated to much higher levels in membrane than storage lipids, comprising more than 60% of total fatty acid in both phosphatidylcholine (PC) and phosphatidylethanolamine (PE) versus 26% in diacylglycerol (DAG) and 12% in triacylglycerol (TAG) indicating bottlenecks in the transfer of CPA from PC to DAG and from DAG to TAG. Upon co-expression of SfLPAT with EcCPS, di-CPA-PC increased by ~50% relative to lines expressing EcCPS alone with the di-CPA-PC primarily observed in the embryonic axis and mono-CPA-PC primarily in cotyledon tissue. EcCPS-SfLPAT lines revealed a redistribution of CPA from the sn-1 to sn-2 positions within PC and PE that was associated with a doubling of CPA accumulation in both DAG and TAG. The identification of metabolic bottlenecks in acyl transfer between site of synthesis (phospholipids) and deposition in storage oils (TAGs) lays the foundation for the optimizing CPA accumulation through directed engineering of oil synthesis in target crops.
Collapse
Affiliation(s)
- Xiao‐Hong Yu
- Department of Biochemistry and Cell BiologyStony Brook UniversityStony BrookNYUSA
| | - Rebecca E. Cahoon
- Center for Plant Science InnovationDepartment of BiochemistryUniversity of Nebraska‐LincolnLincolnNEUSA
| | - Patrick J. Horn
- Department of Biological SciencesBioDiscovery InstituteUniversity of North TexasDentonTXUSA
- Present address:
DOE‐Plant Research LaboratoryMichigan State UniversityEast LansingMIUSA
| | - Hai Shi
- Biology DepartmentBrookhaven National LaboratoryUptonNYUSA
| | - Richa R. Prakash
- Department of Biochemistry and Cell BiologyStony Brook UniversityStony BrookNYUSA
- Present address:
Department of Natural SciencesSuffolk County Community CollegeBrentwoodNYUSA
| | - Yuanheng Cai
- Department of Biochemistry and Cell BiologyStony Brook UniversityStony BrookNYUSA
| | - Maegan Hearney
- Biology DepartmentBrookhaven National LaboratoryUptonNYUSA
| | - Kent D. Chapman
- Department of Biological SciencesBioDiscovery InstituteUniversity of North TexasDentonTXUSA
| | - Edgar B. Cahoon
- Center for Plant Science InnovationDepartment of BiochemistryUniversity of Nebraska‐LincolnLincolnNEUSA
| | - Jorg Schwender
- Department of Biochemistry and Cell BiologyStony Brook UniversityStony BrookNYUSA
- Biology DepartmentBrookhaven National LaboratoryUptonNYUSA
| | - John Shanklin
- Department of Biochemistry and Cell BiologyStony Brook UniversityStony BrookNYUSA
- Biology DepartmentBrookhaven National LaboratoryUptonNYUSA
| |
Collapse
|
103
|
Lung SC, Liao P, Yeung EC, Hsiao AS, Xue Y, Chye ML. Arabidopsis ACYL-COA-BINDING PROTEIN1 interacts with STEROL C4-METHYL OXIDASE1-2 to modulate gene expression of homeodomain-leucine zipper IV transcription factors. THE NEW PHYTOLOGIST 2018; 218:183-200. [PMID: 29288621 DOI: 10.1111/nph.14965] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/20/2017] [Indexed: 05/18/2023]
Abstract
Fatty acids (FAs) and sterols constitute building blocks of eukaryotic membranes and lipid signals. Co-regulation of FA and sterol synthesis is mediated by sterol regulatory element-binding proteins in animals but remains elusive in plants. We reported recently that Arabidopsis ACYL-COA-BINDING PROTEIN1 (ACBP1) modulates sterol synthesis via protein-protein interaction with STEROL C4-METHYL OXIDASE1-1 (SMO1-1). Herein, ACBP1 was demonstrated to co-express and interact with SMO1-2 by yeast two-hybrid, co-localization, pull-down, co-immunoprecipitation and β-glucuronidase assays. SMO1-2 silenced in acbp1 was used in phenotyping, GC-MS and expression profiling. ACBP1 co-expressed with SMO1-2 in embryo sacs, pollen and trichomes, corroborating with cooperative tissue-specific functions unseen with SMO1-1. SMO1-2 silencing in acbp1 impaired seed development, male and female gamete transmission, and pollen function. Genes encoding homeodomain-leucine zipper IV transcription factors (HDG5, HDG10, HDG11 and GLABRA2), which potentially bind phospholipids/sterols, were transcribed aberrantly. GLABRA2 targets (MYB23, MUM4 and PLDα1) were misregulated, causing glabra2-resembling trichome, seed coat mucilage and oil-accumulating phenotypes. Together with altered sterol and FA compositions upon ACBP1 mutation and/or SMO1-2 silencing, ACBP1-SMO1 interaction appears to mediate homeostatic co-regulation of FAs and sterols, which serve as lipid modulators for gene expression of homeodomain-leucine zipper IV transcription factors.
Collapse
Affiliation(s)
- Shiu-Cheung Lung
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Pan Liao
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Edward C Yeung
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - An-Shan Hsiao
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Yan Xue
- 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
| |
Collapse
|
104
|
Sato N, Awai K. "Prokaryotic Pathway" Is Not Prokaryotic: Noncyanobacterial Origin of the Chloroplast Lipid Biosynthetic Pathway Revealed by Comprehensive Phylogenomic Analysis. Genome Biol Evol 2018; 9:3162-3178. [PMID: 29145606 PMCID: PMC5716074 DOI: 10.1093/gbe/evx238] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2017] [Indexed: 12/12/2022] Open
Abstract
Lipid biosynthesis within the chloroplast, or more generally plastids, was conventionally called “prokaryotic pathway,” which produces glycerolipids bearing C18 acids at the sn-1 position and C16 acids at the sn-2 position, as in cyanobacteria such as Anabaena and Synechocystis. This positional specificity is determined during the synthesis of phosphatidate, which is a precursor to diacylglycerol, the acceptor of galactose for the synthesis of galactolipids. The first acylation at sn-1 is catalyzed by glycerol-3-phosphate acyltransferase (GPAT or GPT), whereas the second acylation at sn-2 is performed by lysophosphatidate acyltransferase (LPAAT, AGPAT, or PlsC). Here we present comprehensive phylogenomic analysis of the origins of various acyltransferases involved in the synthesis of phosphatidate, as well as phosphatidate phosphatases in the chloroplasts. The results showed that the enzymes involved in the two steps of acylation in cyanobacteria and chloroplasts are entirely phylogenetically unrelated despite a previous report stating that the chloroplast LPAAT (ATS2) and cyanobacterial PlsC were sister groups. Phosphatidate phosphatases were separated into eukaryotic and prokaryotic clades, and the chloroplast enzymes were not of cyanobacterial origin, in contrast with another previous report. These results indicate that the lipid biosynthetic pathway in the chloroplasts or plastids did not originate from the cyanobacterial endosymbiont and is not “prokaryotic” in the context of endosymbiotic theory of plastid origin. This is another line of evidence for the discontinuity of plastids and cyanobacteria, which has been suggested in the glycolipid biosynthesis.
Collapse
Affiliation(s)
- Naoki Sato
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Japan.,Japan Science and Technology Agency, CREST, Tokyo, Japan
| | - Koichiro Awai
- Japan Science and Technology Agency, CREST, Tokyo, Japan.,Department of Biological Science, Faculty of Science, and Research Institute of Electronics, Shizuoka University, Japan
| |
Collapse
|
105
|
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]
|
106
|
Yang Y, Benning C. Functions of triacylglycerols during plant development and stress. Curr Opin Biotechnol 2018; 49:191-198. [DOI: 10.1016/j.copbio.2017.09.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 06/16/2017] [Accepted: 09/15/2017] [Indexed: 10/18/2022]
|
107
|
Müller AO, Ischebeck T. Characterization of the enzymatic activity and physiological function of the lipid droplet-associated triacylglycerol lipase AtOBL1. THE NEW PHYTOLOGIST 2018; 217:1062-1076. [PMID: 29178188 DOI: 10.1111/nph.14902] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 10/17/2017] [Indexed: 05/04/2023]
Abstract
Similar to seeds, pollen tubes contain lipid droplets that store triacylglycerol (TAG), but the fate of this TAG as well as the enzymes involved in its breakdown are unknown. Therefore, two potential TAG lipases from tobacco and Arabidopsis, NtOBL1 (Oil body lipase 1) and AtOBL1, were investigated, especially with respect to their importance for pollen tube growth. We expressed NtOBL1 and AtOBL1 as fluorescent fusion proteins to study their localization by confocal microscopy. Furthermore, we overexpressed AtOBL1 in Nicotiana benthamiana leaves to characterize it enzymatically. The obl1 mutant was studied in respect to its pollen tube growth in vivo and its seed germination. Both NtOBL1 and AtOBL1 localized to lipid droplets. AtOBL1 was abundant in pollen tubes and seedlings, and acted as a lipase on TAG, diacylglycerol and 1-monoacylglycerol at a pH optimum of 5.5. The obl1 mutant was hampered in pollen tube growth, whereas seedling establishment was not affected under optimal conditions, even though AtOBL1 accounted for a major lipase activity in seeds. TAG could be a direct precursor for the synthesis of membrane lipids in pollen tubes and proteins of the OBL family involved in the flux of acyl groups.
Collapse
Affiliation(s)
- Anna Ophelia Müller
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Till Ischebeck
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| |
Collapse
|
108
|
Inês C, Parra-Lobato MC, Paredes MA, Labrador J, Gallardo M, Saucedo-García M, Gavilanes-Ruiz M, Gomez-Jimenez MC. Sphingolipid Distribution, Content and Gene Expression during Olive-Fruit Development and Ripening. FRONTIERS IN PLANT SCIENCE 2018; 9:28. [PMID: 29434611 PMCID: PMC5790798 DOI: 10.3389/fpls.2018.00028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Accepted: 01/09/2018] [Indexed: 05/03/2023]
Abstract
Plant sphingolipids are involved in the building of the matrix of cell membranes and in signaling pathways of physiological processes and environmental responses. However, information regarding their role in fruit development and ripening, a plant-specific process, is unknown. The present study seeks to determine whether and, if so, how sphingolipids are involved in fleshy-fruit development and ripening in an oil-crop species such as olive (Olea europaea L. cv. Picual). Here, in the plasma-membranes of live protoplasts, we used fluorescence to examine various specific lipophilic stains in sphingolipid-enriched regions and investigated the composition of the sphingolipid long-chain bases (LCBs) as well as the expression patterns of sphingolipid-related genes, OeSPT, OeSPHK, OeACER, and OeGlcCerase, during olive-fruit development and ripening. The results demonstrate increased sphingolipid content and vesicle trafficking in olive-fruit protoplasts at the onset of ripening. Moreover, the concentration of LCB [t18:1(8Z), t18:1 (8E), t18:0, d18:2 (4E/8Z), d18:2 (4E/8E), d18:1(4E), and 1,4-anhydro-t18:1(8E)] increases during fruit development to reach a maximum at the onset of ripening, although these molecular species decreased during fruit ripening. On the other hand, OeSPT, OeSPHK, and OeGlcCerase were expressed differentially during fruit development and ripening, whereas OeACER gene expression was detected only at the fully ripe stage. The results provide novel data about sphingolipid distribution, content, and biosynthesis/turnover gene transcripts during fleshy-fruit ripening, indicating that all are highly regulated in a developmental manner.
Collapse
Affiliation(s)
- Carla Inês
- Department of Plant Physiology, University of Extremadura, Badajoz, Spain
| | | | - Miguel A. Paredes
- Department of Plant Physiology, University of Extremadura, Badajoz, Spain
| | - Juana Labrador
- Department of Plant Physiology, University of Extremadura, Badajoz, Spain
| | | | - Mariana Saucedo-García
- Institute of Agricultural Sciences, Autonomous University of the State of Hidalgo, Tulancingo, Mexico
| | - Marina Gavilanes-Ruiz
- Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | | |
Collapse
|
109
|
Tang G, Xu P, Ma W, Wang F, Liu Z, Wan S, Shan L. Seed-Specific Expression of AtLEC1 Increased Oil Content and Altered Fatty Acid Composition in Seeds of Peanut ( Arachis hypogaea L.). FRONTIERS IN PLANT SCIENCE 2018; 9:260. [PMID: 29559985 PMCID: PMC5845668 DOI: 10.3389/fpls.2018.00260] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 02/14/2018] [Indexed: 05/20/2023]
Abstract
Peanut (Arachis hypogaea L.) is one of the major oil crops and is the fifth largest source of plant oils in the world. Numerous genes participate in regulating the biosynthesis and accumulation of the storage lipids in seeds or other reservoir organs, among which several transcription factors, such as LEAFY COTYLEDON1 (AtLEC1), LEC2, and WRINKLED1 (WRI1), involved in embryo development also control the lipid reservoir in seeds. In this study, the AtLEC1 gene was transferred into the peanut genome and expressed in a seed-specific manner driven by the NapinA full-length promoter or its truncated 230-bp promoter. Four homozygous transgenic lines, two lines with the longer promoter and the other two with the truncated one, were selected for further analysis. The AtLEC1 mRNA level and the corresponding protein accumulation in different transgenic overexpression lines were altered, and the transgenic plants grew and developed normally without any detrimental effects on major agronomic traits. In the developing seeds of transgenic peanuts, the mRNA levels of a series of genes were upregulated. These genes are associated with fatty acid (FA) biosynthesis and lipid accumulation. The former set of genes included the homomeric ACCase A (AhACC II), the BC subunit of heteromeric ACCase (AhBC4), ketoacyl-ACP synthetase (AhKAS II), and stearoyl-ACP desaturase (AhSAD), while the latter ones were the diacylglycerol acyltransferases and oleosins (AhDGAT1, AhDGAT2, AhOle1, AhOle2, and AhOle3). The oil content and seed weight increased by 4.42-15.89% and 11.1-22.2%, respectively, and the levels of major FA components including stearic acid, oleic acid, and linoleic acid changed significantly in all different lines.
Collapse
Affiliation(s)
- Guiying Tang
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Pingli Xu
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Wenhua Ma
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
- College of Life Sciences, Shandong University, Jinan, China
| | - Fang Wang
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
- College of Life Sciences, Shandong Normal University, Jinan, China
| | - Zhanji Liu
- Shandong Cotton Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Shubo Wan
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
- College of Life Sciences, Shandong University, Jinan, China
- *Correspondence: Lei Shan, Shubo Wan,
| | - Lei Shan
- Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Bio-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
- College of Life Sciences, Shandong University, Jinan, China
- College of Life Sciences, Shandong Normal University, Jinan, China
- *Correspondence: Lei Shan, Shubo Wan,
| |
Collapse
|
110
|
Abdullah HM, Chhikara S, Akbari P, Schnell DJ, Pareek A, Dhankher OP. Comparative transcriptome and metabolome analysis suggests bottlenecks that limit seed and oil yields in transgenic Camelina sativa expressing diacylglycerol acyltransferase 1 and glycerol-3-phosphate dehydrogenase. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:335. [PMID: 30574188 PMCID: PMC6299664 DOI: 10.1186/s13068-018-1326-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 11/30/2018] [Indexed: 05/14/2023]
Abstract
BACKGROUND Camelina sativa has attracted much interest as alternative renewable resources for biodiesel, other oil-based industrial products and a source for edible oils. Its unique oil attributes attract research to engineering new varieties of improved oil quantity and quality. The overexpression of enzymes catalyzing the synthesis of the glycerol backbone and the sequential conjugation of fatty acids into this backbone is a promising approach for increasing the levels of triacylglycerol (TAG). In a previous study, we co-expressed the diacylglycerol acyltransferase (DGAT1) and glycerol-3-phosphate dehydrogenase (GPD1), involved in TAG metabolism, in Camelina seeds. Transgenic plants exhibited a higher-percentage seed oil content, a greater seed mass, and overall improved seed and oil yields relative to wild-type plants. To further increase seed oil content in Camelina, we utilized metabolite profiling, in conjunction with transcriptome profiling during seed development to examine potential rate-limiting step(s) in the production of building blocks for TAG biosynthesis. RESULTS Transcriptomic analysis revealed approximately 2518 and 3136 transcripts differentially regulated at significant levels in DGAT1 and GPD1 transgenics, respectively. These transcripts were found to be involved in various functional categories, including alternative metabolic routes in fatty acid synthesis, TAG assembly, and TAG degradation. We quantified the relative contents of over 240 metabolites. Our results indicate major metabolic switches in transgenic seeds associated with significant changes in the levels of glycerolipids, amino acids, sugars, and organic acids, especially the TCA cycle and glycolysis intermediates. CONCLUSIONS From the transcriptomic and metabolomic analysis of DGAT1, GPD1 and DGAT1 + GPD1 expressing lines of C. sativa, we conclude that TAG production is limited by (1) utilization of fixed carbon from the source tissues supported by the increase in glycolysis pathway metabolites and decreased transcripts levels of transcription factors controlling fatty acids synthesis; (2) TAG accumulation is limited by the activity of lipases/hydrolases that hydrolyze TAG pool supported by the increase in free fatty acids and monoacylglycerols. This comparative transcriptomics and metabolomics approach is useful in understanding the regulation of TAG biosynthesis, identifying bottlenecks, and the corresponding genes controlling these pathways identified as limitations, for generating Camelina varieties with improved seed and oil yields.
Collapse
Affiliation(s)
- Hesham M. Abdullah
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 USA
- Biotechnology Department, Faculty of Agriculture, Al-Azhar University, Cairo, 11651 Egypt
- Present Address: Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Sudesh Chhikara
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 USA
- Present Address: Centre for Biotechnology, Maharshi Dayanand University, Rohtak, 124001 India
| | - Parisa Akbari
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 USA
| | - Danny J. Schnell
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Ashwani Pareek
- Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 100067 India
| | - Om Parkash Dhankher
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 USA
| |
Collapse
|
111
|
Woodfield HK, Cazenave-Gassiot A, Haslam RP, Guschina IA, Wenk MR, Harwood JL. Using lipidomics to reveal details of lipid accumulation in developing seeds from oilseed rape (Brassica napus L.). Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1863:339-348. [PMID: 29275220 PMCID: PMC5791847 DOI: 10.1016/j.bbalip.2017.12.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 12/11/2017] [Accepted: 12/19/2017] [Indexed: 12/21/2022]
Abstract
With dwindling available agricultural land, concurrent with increased demand for oil, there is much current interest in raising oil crop productivity. We have been addressing this issue by studying the regulation of oil accumulation in oilseed rape (Brassica napus L). As part of this research we have carried out a detailed lipidomic analysis of developing seeds. The molecular species distribution in individual lipid classes revealed quite distinct patterns and showed where metabolic connections were important. As the seeds developed, the molecular species distributions changed, especially in the period of early (20 days after flowering, DAF) to mid phase (27DAF) of oil accumulation. The patterns of molecular species of diacylglycerol, phosphatidylcholine and acyl-CoAs were used to predict the possible relative contributions of diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase to triacylglycerol production. Our calculations suggest that DGAT may hold a more important role in influencing the molecular composition of TAG. Enzyme selectivity had an important influence on the final molecular species patterns. Our data contribute significantly to our understanding of lipid accumulation in the world's third most important oil crop. Lipidomic analysis of developing rapeseed seeds is reported Results show distinct differences between lipid classes Changes in molecular species distributions were found during development The data were used to evaluate the contribution of different synthetic pathways
Collapse
Affiliation(s)
| | - Amaury Cazenave-Gassiot
- Department of Biochemistry, National University of Singapore, Singapore 117587, Singapore; Singapore Lipidomics Incubator (SLING), Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore
| | - Richard P Haslam
- Department of Plant Sciences, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK
| | | | - Markus R Wenk
- Department of Biochemistry, National University of Singapore, Singapore 117587, Singapore; Singapore Lipidomics Incubator (SLING), Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore.
| | - John L Harwood
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.
| |
Collapse
|
112
|
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).
Collapse
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.
| |
Collapse
|
113
|
Li-Beisson Y, Neunzig J, Lee Y, Philippar K. Plant membrane-protein mediated intracellular traffic of fatty acids and acyl lipids. CURRENT OPINION IN PLANT BIOLOGY 2017; 40:138-146. [PMID: 28985576 DOI: 10.1016/j.pbi.2017.09.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 05/24/2023]
Abstract
In plants, de novo synthesis of fatty acids (FAs) occurs in plastids, whereas assembly and modification of acyl lipids is accomplished in the endoplasmic reticulum (ER) and plastids as well as in mitochondria. Subsequently, lipophilic compounds are distributed within the cell and delivered to their destination site. Thus, constant acyl-exchanges between subcellular compartments exist. These can occur via several modes of transport and plant membrane-intrinsic proteins for FA/lipid transfer have been shown to play an essential role in delivery and distribution. Lately, substantial progress has been made in identification and characterization of transport proteins for lipid compounds in plant organelle membranes. In this review, we focus on our current understanding of protein mediated lipid traffic between organelles of land plants.
Collapse
Affiliation(s)
- Yonghua Li-Beisson
- CEA, CNRS and Aix-Marseille Université, Institut de Biosciences et Biotechnologies d'Aix-Marseille, UMR 7265, CEA Cadarache, Saint-Paul-lez Durance F-13108, France
| | - Jens Neunzig
- Saarland University, Center for Human- and Molecular Biology - Plant Biology, Campus A 2.4, D-66123 Saarbrücken, Germany
| | - Youngsook Lee
- Division of Integrative Bioscience and Biotechnology, POSTECH, Pohang 37673, Republic of Korea
| | - Katrin Philippar
- Saarland University, Center for Human- and Molecular Biology - Plant Biology, Campus A 2.4, D-66123 Saarbrücken, Germany.
| |
Collapse
|
114
|
Pick U, Avidan O. Triacylglycerol is produced from starch and polar lipids in the green alga Dunaliella tertiolecta. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:4939-4950. [PMID: 28992231 PMCID: PMC5853294 DOI: 10.1093/jxb/erx280] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The halotolerant green alga Dunaliella tertiolecta accumulates starch and triacylglycerol (TAG) amounting to 70% and 10-15% of total cellular carbon, respectively, when exposed to nitrogen (N) deprivation. The purpose of this study was to clarify the inter-relationships between the biosynthesis of TAG, starch, and polar lipids (PLs) in this alga. Pulse labeling with [14C]bicarbonate was utilized to label starch and [14C]palmitic acid (PlA) to label lipids. Transfer of 14C into TAG was measured and used to calculate rates of synthesis. About two-thirds of the carbon in TAG originates from starch, and one-third is made de novo by direct CO2 assimilation. The level made from degradation of pre-formed PLs is estimated to be very small. Most of the de novo synthesis involves fatty acid transfer through PLs made during the first day of N deprivation. The results suggest that starch made by photosynthetic carbon assimilation at the early stages of N deprivation is utilized for synthesis of TAG. Trans-acylation from PLs is the second major contributor to TAG biosynthesis. The utilization of starch for TAG biosynthesis may have biotechnological applications to optimize TAG biosynthesis in algae.
Collapse
Affiliation(s)
- Uri Pick
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
- Correspondence:
| | - Omri Avidan
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| |
Collapse
|
115
|
Song Y, Wang XD, Rose RJ. Oil body biogenesis and biotechnology in legume seeds. PLANT CELL REPORTS 2017; 36:1519-1532. [PMID: 28866824 PMCID: PMC5602053 DOI: 10.1007/s00299-017-2201-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 08/23/2017] [Indexed: 05/08/2023]
Abstract
The seeds of many legume species including soybean, Pongamia pinnata and the model legume Medicago truncatula store considerable oil, apart from protein, in their cotyledons. However, as a group, legume storage strategies are quite variable and provide opportunities for better understanding of carbon partitioning into different storage products. Legumes with their ability to fix nitrogen can also increase the sustainability of agricultural systems. This review integrates the cell biology, biochemistry and molecular biology of oil body biogenesis before considering biotechnology strategies to enhance oil body biosynthesis. Cellular aspects of packaging triacylglycerol (TAG) into oil bodies are emphasized. Enhancing seed oil content has successfully focused on the up-regulation of the TAG biosynthesis pathways using overexpression of enzymes such as diacylglycerol acyltransferase1 and transcription factors such as WRINKLE1 and LEAFY COTYLEDON1. While these strategies are central, decreasing carbon flow into other storage products and maximizing the packaging of oil bodies into the cytoplasm are other strategies that need further examination. Overall there is much potential for integrating carbon partitioning, up-regulation of fatty acid and TAG synthesis and oil body packaging, for enhancing oil levels. In addition to the potential for integrated strategies to improving oil yields, the capacity to modify fatty acid composition and use of oil bodies as platforms for the production of recombinant proteins in seed of transgenic legumes provide other opportunities for legume biotechnology.
Collapse
Affiliation(s)
- Youhong Song
- School of Agronomy, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Xin-Ding Wang
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Ray J Rose
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia.
| |
Collapse
|
116
|
|
117
|
Yurchenko O, Shockey JM, Gidda SK, Silver MI, Chapman KD, Mullen RT, Dyer JM. Engineering the production of conjugated fatty acids in Arabidopsis thaliana leaves. PLANT BIOTECHNOLOGY JOURNAL 2017; 15:1010-1023. [PMID: 28083898 PMCID: PMC5506653 DOI: 10.1111/pbi.12695] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/28/2016] [Accepted: 01/05/2017] [Indexed: 05/23/2023]
Abstract
The seeds of many nondomesticated plant species synthesize oils containing high amounts of a single unusual fatty acid, many of which have potential usage in industry. Despite the identification of enzymes for unusual oxidized fatty acid synthesis, the production of these fatty acids in engineered seeds remains low and is often hampered by their inefficient exclusion from phospholipids. Recent studies have established the feasibility of increasing triacylglycerol content in plant leaves, which provides a novel approach for increasing energy density of biomass crops. Here, we determined whether the fatty acid composition of leaf oil could be engineered to accumulate unusual fatty acids. Eleostearic acid (ESA) is a conjugated fatty acid produced in seeds of the tung tree (Vernicia fordii) and has both industrial and nutritional end-uses. Arabidopsis thaliana lines with elevated leaf oil were first generated by transforming wild-type, cgi-58 or pxa1 mutants (the latter two of which contain mutations disrupting fatty acid breakdown) with the diacylglycerol acyltransferases (DGAT1 or DGAT2) and/or oleosin genes from tung. High-leaf-oil plant lines were then transformed with tung FADX, which encodes the fatty acid desaturase/conjugase responsible for ESA synthesis. Analysis of lipids in leaves revealed that ESA was efficiently excluded from phospholipids, and co-expression of tung FADX and DGAT2 promoted a synergistic increase in leaf oil content and ESA accumulation. Taken together, these results provide a new approach for increasing leaf oil content that is coupled with accumulation of unusual fatty acids. Implications for production of biofuels, bioproducts, and plant-pest interactions are discussed.
Collapse
Affiliation(s)
- Olga Yurchenko
- USDA‐ARSUS Arid‐Land Agricultural Research CenterMaricopaAZUSA
| | - Jay M. Shockey
- USDA‐ARSSouthern Regional Research CenterNew OrleansLAUSA
| | - Satinder K. Gidda
- Department of Molecular and Cellular BiologyUniversity of GuelphGuelphONCanada
| | - Maxwell I. Silver
- Department of Molecular and Cellular BiologyUniversity of GuelphGuelphONCanada
| | - Kent D. Chapman
- Department of Biological SciencesUniversity of North TexasDentonTXUSA
| | - Robert T. Mullen
- Department of Molecular and Cellular BiologyUniversity of GuelphGuelphONCanada
| | - John M. Dyer
- USDA‐ARSUS Arid‐Land Agricultural Research CenterMaricopaAZUSA
| |
Collapse
|
118
|
Lipid metabolism and potentials of biofuel and high added-value oil production in red algae. World J Microbiol Biotechnol 2017; 33:74. [DOI: 10.1007/s11274-017-2236-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/01/2017] [Indexed: 10/20/2022]
|
119
|
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]
|
120
|
Sturtevant D, Dueñas ME, Lee YJ, Chapman KD. Three-dimensional visualization of membrane phospholipid distributions in Arabidopsis thaliana seeds: A spatial perspective of molecular heterogeneity. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:268-281. [PMID: 27919665 DOI: 10.1016/j.bbalip.2016.11.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 11/21/2016] [Accepted: 11/30/2016] [Indexed: 11/29/2022]
Abstract
Arabidopsis thaliana has been widely used as a model plant to study acyl lipid metabolism. Seeds of A. thaliana are quite small (approximately 500×300μm and weigh ~20μg), making lipid compositional analyses of single seeds difficult to achieve. Here we have used matrix assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) to map and visualize the three-dimensional spatial distributions of two common membrane phospholipid classes, phosphatidylcholine (PC) and phosphatidylinositol (PI), in single A. thaliana seeds. The 3D images revealed distinct differences in distribution of several molecular species of both phospholipids among different seed tissues. Using data from these 3D reconstructions, the PC and PI mol% lipid profiles were calculated for the embryonic axis, cotyledons, and peripheral endosperm, and these data agreed well with overall quantification of these lipids in bulk seed extracts analyzed by conventional electrospray ionization-mass spectrometry (ESI-MS). In addition, MALDI-MSI was used to profile PC and PI molecular species in seeds of wild type, fad2-1, fad3-2, fad6-1, and fae1-1 acyl lipid mutants. The resulting distributions revealed previously unobserved changes in spatial distribution of several lipid molecular species, and were used to suggest new insights into biochemical heterogeneity of seed lipid metabolism. These studies highlight the value of mass spectrometry imaging to provide unprecedented spatial and chemical resolution of metabolites directly in samples even as small as a single A. thaliana seeds, and allow for expanded imaging of plant metabolites to improve our understanding of plant lipid metabolism from a spatial perspective.
Collapse
Affiliation(s)
- Drew Sturtevant
- Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA.
| | - Maria Emilia Dueñas
- Ames Laboratory, US Department of Energy, Ames, IA 50011, USA; Department of Chemistry, Iowa State University of Science and Technology, Ames, IA 50011, USA.
| | - Young-Jin Lee
- Ames Laboratory, US Department of Energy, Ames, IA 50011, USA; Department of Chemistry, Iowa State University of Science and Technology, Ames, IA 50011, USA.
| | - Kent D Chapman
- Department of Biological Sciences, University of North Texas, Denton, TX 76203, USA.
| |
Collapse
|
121
|
Wu S, Alseekh S, Cuadros-Inostroza Á, Fusari CM, Mutwil M, Kooke R, Keurentjes JB, Fernie AR, Willmitzer L, Brotman Y. Combined Use of Genome-Wide Association Data and Correlation Networks Unravels Key Regulators of Primary Metabolism in Arabidopsis thaliana. PLoS Genet 2016; 12:e1006363. [PMID: 27760136 PMCID: PMC5070769 DOI: 10.1371/journal.pgen.1006363] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/13/2016] [Indexed: 01/12/2023] Open
Abstract
Plant primary metabolism is a highly coordinated, central, and complex network of biochemical processes regulated at both the genetic and post-translational levels. The genetic basis of this network can be explored by analyzing the metabolic composition of genetically diverse genotypes in a given plant species. Here, we report an integrative strategy combining quantitative genetic mapping and metabolite‒transcript correlation networks to identify functional associations between genes and primary metabolites in Arabidopsis thaliana. Genome-wide association study (GWAS) was used to identify metabolic quantitative trait loci (mQTL). Correlation networks built using metabolite and transcript data derived from a previously published time-course stress study yielded metabolite‒transcript correlations identified by covariation. Finally, results obtained in this study were compared with mQTL previously described. We applied a statistical framework to test and compare the performance of different single methods (network approach and quantitative genetics methods, representing the two orthogonal approaches combined in our strategy) with that of the combined strategy. We show that the combined strategy has improved performance manifested by increased sensitivity and accuracy. This combined strategy allowed the identification of 92 candidate associations between structural genes and primary metabolites, which not only included previously well-characterized gene‒metabolite associations, but also revealed novel associations. Using loss-of-function mutants, we validated two of the novel associations with genes involved in tyrosine degradation and in β-alanine metabolism. In conclusion, we demonstrate that applying our integrative strategy to the largely untapped resource of metabolite-transcript associations can facilitate the discovery of novel metabolite-related genes. This integrative strategy is not limited to A. thaliana, but generally applicable to other plant species.
Collapse
Affiliation(s)
- Si Wu
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Saleh Alseekh
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Álvaro Cuadros-Inostroza
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
- MetaSysX GmbH, Potsdam-Golm, Germany
| | - Corina M. Fusari
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Marek Mutwil
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Rik Kooke
- Laboratory of Genetics, Wageningen University, Wageningen, the Netherlands
| | | | - Alisdair R. Fernie
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Lothar Willmitzer
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Yariv Brotman
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
- Department of Life Sciences, Ben Gurion University of the Negev, Beersheva, Israel
- * E-mail:
| |
Collapse
|
122
|
Affiliation(s)
- Kent Chapman
- Center for Plant Lipid Research and Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203, United States
| | - Ivo Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany; Department of Plant Biochemistry, Goettingen Center for Molecular Biosciences (GZMB), Georg-August-University, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany.; Department of Plant Biochemistry, International Center for Advanced Studies of Energy Conversion (ICASEC), Georg-August-University, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| |
Collapse
|
123
|
Meï CE, Cussac M, Haslam RP, Beaudoin F, Wong YS, Maréchal E, Rébeillé F. C1 Metabolism Inhibition and Nitrogen Deprivation Trigger Triacylglycerol Accumulation in Arabidopsis thaliana Cell Cultures and Highlight a Role of NPC in Phosphatidylcholine-to-Triacylglycerol Pathway. FRONTIERS IN PLANT SCIENCE 2016; 7:2014. [PMID: 28101097 PMCID: PMC5209388 DOI: 10.3389/fpls.2016.02014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 12/19/2016] [Indexed: 05/20/2023]
Abstract
Triacylglycerol (TAG) accumulation often occurs in growth limiting conditions such as nutrient deprivations. We analyzed and compared the lipid contents of Arabidopsis cells grown under two conditions that inhibited growth as a way to study interactions between membrane and storage lipids. In order to inhibit C1 metabolism, the first condition utilized methotrexate (MTX), a drug that inhibits methyl transfer reactions and potentially reduces Pi-choline synthesis, the polar head of phosphatidylcholine (PC). MTX-treated cells displayed a 10- to 15-fold increase in TAG compared to that found in control cells. This corresponded to a net increase of lipids as the total amount of membrane glycerolipids was minimally affected. Under this condition, PC homeostasis appeared tightly regulated and not strictly dependent on the rate of Pi-choline synthesis. The second condition we investigated involved nitrogen deprivation. Here, we observed a 40-fold increase of TAG. In these cells, the overall lipid content remained unchanged, but membrane lipids decreased by a factor of two suggesting a reduction of the membrane network and a rerouting of membrane lipids to storage lipids. Under all conditions, fatty acid (FA) analyses showed that the FA composition of TAG was comparable to that in PC, but different from that in acyl-CoA, suggesting that TAG accumulation involved PC-derived DAG moieties. In agreement, analyses by qPCR of genes coding for TAG synthesis showed a strong increase of non-specific phospholipase C (NPC) expressions, and experiments using labeled (fluorescent) PC indicated higher rates of PC-to-TAG conversion under both situations. These results highlight a role for NPC in plant cell oil production.
Collapse
Affiliation(s)
- Coline E. Meï
- Laboratoire de Physiologie Cellulaire Végétale, UMR 5168 CNRS – CEA – INRA – Université Grenoble Alpes, Bioscience and Biotechnologies Institute of GrenobleCEA-Grenoble, Grenoble, France
| | - Mathilde Cussac
- Laboratoire de Physiologie Cellulaire Végétale, UMR 5168 CNRS – CEA – INRA – Université Grenoble Alpes, Bioscience and Biotechnologies Institute of GrenobleCEA-Grenoble, Grenoble, France
| | - Richard P. Haslam
- Department of Biological Chemistry and Crop Protection, Rothamsted ResearchHarpenden, UK
| | - Frédéric Beaudoin
- Department of Biological Chemistry and Crop Protection, Rothamsted ResearchHarpenden, UK
| | - Yung-Sing Wong
- Département de Pharmacochimie Moléculaire, UMR 5063 CNRS – Université Grenoble AlpesGrenoble, France
| | - Eric Maréchal
- Laboratoire de Physiologie Cellulaire Végétale, UMR 5168 CNRS – CEA – INRA – Université Grenoble Alpes, Bioscience and Biotechnologies Institute of GrenobleCEA-Grenoble, Grenoble, France
| | - Fabrice Rébeillé
- Laboratoire de Physiologie Cellulaire Végétale, UMR 5168 CNRS – CEA – INRA – Université Grenoble Alpes, Bioscience and Biotechnologies Institute of GrenobleCEA-Grenoble, Grenoble, France
- *Correspondence: Fabrice Rébeillé,
| |
Collapse
|