Expression of a Bacterial Trehalose-6-phosphate Synthase otsA Increases Oil Accumulation in Plant Seeds and Vegetative Tissues

We previously demonstrated that exogenous trehalose 6-phosphate (T6P) treatment stabilized WRINKLED1 (WRI1), a master transcriptional regulator of fatty acid (FA) synthesis and increased total FA content in Brassica napus (B. napus) embryo suspension cell culture. Here, we explore Arabidopsis lines heterologously expressing the Escherichia coli T6P synthase (otsA) or T6P phosphatase (otsB) to refine our understanding regarding the role of T6P in regulating fatty acid synthesis both in seeds and vegetative tissues. Arabidopsis 35S:otsA transgenic seeds showed an increase of 13% in fatty acid content compared to those of wild type (WT), while seeds of 35:otsB transgenic seeds showed a reduction of 12% in fatty acid content compared to WT. Expression of otsB significantly reduced the level of WRI1 and expression of its target genes in developing seeds. Like Arabidopsis seeds constitutively expressing otsA, transient expression of otsA in Nicotiana benthamiana leaves resulted in strongly elevated levels of T6P. This was accompanied by an increase of 29% in de novo fatty acid synthesis rate, a 2.3-fold increase in triacylglycerol (TAG) and a 20% increase in total fatty acid content relative to empty vector (EV) controls. Taken together, these data support the heterologous expression of otsA as an approach to increasing TAG accumulation in plant seeds and vegetative tissues.

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Comparative Transcriptome Analysis Reveals an Efficient Mechanism of α-Linolenic Acid in Tree Peony Seeds

International Journal of Molecular Sciences ◽

10.3390/ijms20010065 ◽

2018 ◽

Vol 20 (1) ◽

pp. 65 ◽

Cited By ~ 4

Author(s):

Qingyu Zhang ◽

Rui Yu ◽

Daoyang Sun ◽

Md Rahman ◽

Lihang Xie ◽

...

Keyword(s):

Fatty Acid ◽

Linolenic Acid ◽

Fatty Acid Synthesis ◽

Acid Content ◽

Fatty Acid Content ◽

Acid Synthesis ◽

High Unsaturated Fatty Acid ◽

Comparative Transcriptome ◽

Tree Peony ◽

Lipid Metabolism Genes

Tree peony (Paeonia section Moutan DC.) species are woody oil crops with high unsaturated fatty acid content, including α-linolenic acid (ALA/18:3; >40% of the total fatty acid). Comparative transcriptome analyses were carried out to uncover the underlying mechanisms responsible for high and low ALA content in the developing seeds of P. rockii and P. lutea, respectively. Expression analysis of acyl lipid metabolism genes revealed upregulation of select genes involved in plastidial fatty acid synthesis, acyl editing, desaturation, and triacylglycerol assembly in seeds of P. rockii relative to P. lutea. Also, in association with ALA content in seeds, transcript levels for fatty acid desaturases (SAD, FAD2, and FAD3), which encode enzymes necessary for polyunsaturated fatty acid synthesis, were higher in P. rockii compared to P. lutea. Furthermore, the overexpression of PrFAD2 and PrFAD3 in Arabidopsis increased linoleic and ALA content, respectively, and modulated the final ratio 18:2/18:3 in the seed oil. In conclusion, we identified the key steps and validated the necessary desaturases that contribute to efficient ALA synthesis in a woody oil crop. Together, these results will aid to increase essential fatty acid content in seeds of tree peonies and other crops of agronomic interest.

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EPTC Altered Beet Disc Betacyanin Efflux and Fatty Acid Synthesis

Weed Science ◽

10.1017/s0043174500065838 ◽

1976 ◽

Vol 24 (2) ◽

pp. 235-238 ◽

Cited By ~ 19

Author(s):

R. E. Wilkinson ◽

A. E. Smith

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Beta Vulgaris ◽

Total Fatty Acid ◽

Fatty Acid Synthesis ◽

Acid Content ◽

Fatty Acid Content ◽

Acid Synthesis ◽

Total Fatty Acid Content ◽

Naphthalic Anhydride

Betacyanin efflux from “aged” red beet (Beta vulgarisL.) root tissue, measured spectrophotometrically, was increased as temperature and EPTC (S-ethyl dipropylthiocarbamate) concentration increased. Acetate-2-14C (∗Ac) incorporation into the total fatty acid content was inhibited by EPTC. EPTC inhibited the incorporation of∗Ac into the dienoic fatty acids and NA (1,8-naphthalic anhydride) reversed the EPTC induced inhibition of the incorporation of ∗Ac into dienoic fatty acids.

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Effect of Diet Supplementation on the Expression of Bovine Genes Associated with Fatty Acid Synthesis and Metabolism

Bioinformatics and Biology Insights ◽

10.4137/bbi.s4168 ◽

2010 ◽

Vol 4 ◽

pp. BBI.S4168 ◽

Cited By ~ 17

Author(s):

Sandeep J. Joseph ◽

Kelly R. Robbins ◽

Enrique Pavan ◽

Scott L. Pratt ◽

Susan K. Duckett ◽

...

Keyword(s):

Fatty Acid ◽

Fatty Acid Synthesis ◽

Corn Oil ◽

Fatty Acid Content ◽

Fatty Acid Synthetase ◽

Health Benefit ◽

Acid Synthesis ◽

Animal Origin ◽

Expression Of Genes ◽

Diet Supplementation

Conjugated linoleic acids (CLA) are of important nutritional and health benefit to human. Food products of animal origin are their major dietary source and their concentration increases with high concentrate diets fed to animals. To examine the effects of diet supplementation on the expression of genes related to lipid metabolism, 28 Angus steers were fed either pasture only, pasture with soybean hulls and corn oil, pasture with corn grain, or high concentrate diet. At slaughter, samples of subcutaneous adipose tissue were collected, from which RNA was extracted. Relative abundance of gene expression was measured using Affymetrix GeneChip Bovine Genome array. An ANOVA model nested within gene was used to analyze the background adjusted, normalized average difference of probe-level intensities. To control experiment wise error, a false discovery rate of 0.01 was imposed on all contrasts. Expression of several genes involved in the synthesis of enzymes related to fatty acid metabolism and lipogenesis such as stearoyl-CoA desaturase (SCD), fatty acid synthetase (FASN), lipoprotein lipase (LPL), fatty-acyl elongase (LCE) along with several trancription factors and co-activators involved in lipogenesis were found to be differentially expressed. Confirmatory RT-qPCR was done to validate the microarray results, which showed satisfactory correspondence between the two platforms. Results show that changes in diet by increasing dietary energy intake by supplementing high concentrate diet have effects on the transcription of genes encoding enzymes involved in fat metabolism which in turn has effects on fatty acid content in the carcass tissue as well as carcass quality. Corn supplementation either as oil or grain appeared to significantly alter the expression of genes directly associated with fatty acid synthesis.

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Synchronization of hepatic cholesterol synthesis, cholesterol and bile acid content, fatty acid synthesis and plasma free fatty acid levels in the fed and fasted rat

Biochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism ◽

10.1016/0005-2760(73)90212-9 ◽

1973 ◽

Vol 306 (1) ◽

pp. 85-94 ◽

Cited By ~ 22

Author(s):

Walter M. Bortz ◽

Lois A. Steele

Keyword(s):

Fatty Acid ◽

Bile Acid ◽

Free Fatty Acid ◽

Fatty Acid Synthesis ◽

Acid Content ◽

Cholesterol Synthesis ◽

Plasma Free Fatty Acid ◽

Acid Synthesis ◽

Hepatic Cholesterol ◽

Hepatic Cholesterol Synthesis

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Fatty acid synthesis and generation of glycerol-3-phosphate in brown adipose tissue from rats fed a cafeteria diet

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y08-052 ◽

2008 ◽

Vol 86 (7) ◽

pp. 416-423 ◽

Cited By ~ 12

Author(s):

Valéria E. Chaves ◽

Danúbia Frasson ◽

Maria E.S. Martins-Santos ◽

Luiz C.C. Navegantes ◽

Victor D. Galban ◽

...

Keyword(s):

Adipose Tissue ◽

Fatty Acid ◽

Brown Adipose Tissue ◽

Glucose Uptake ◽

Fatty Acid Synthesis ◽

Fatty Acid Content ◽

Acid Synthesis ◽

Cafeteria Diet ◽

Brown Adipose

In vivo fatty acid synthesis and the pathways of glycerol-3-phosphate (G3P) production were investigated in brown adipose tissue (BAT) from rats fed a cafeteria diet for 3 weeks. In spite of BAT activation, the diet promoted an increase in the carcass fatty acid content. Plasma insulin levels were markedly increased in cafeteria diet-fed rats. Two insulin-sensitive processes, in vivo fatty acid synthesis and in vivo glucose uptake (which was used to evaluate G3P generation via glycolysis) were increased in BAT from rats fed the cafeteria diet. Direct glycerol phosphorylation, evaluated by glycerokinase (GyK) activity and incorporation of [U-14C]glycerol into triacylglycerol (TAG)–glycerol, was also markedly increased in BAT from these rats. In contrast, the cafeteria diet induced a marked reduction of BAT glyceroneogenesis, evaluated by phosphoenolpyruvate carboxykinase-C activity and incorporation of [1-14C]pyruvate into TAG–glycerol. BAT denervation resulted in an approximately 50% reduction of GyK activity, but did not significantly affect BAT in vivo fatty acid synthesis, in vivo glucose uptake, or glyceroneogenesis. The data suggest that the supply of G3P for BAT TAG synthesis can be adjusted independently from the sympathetic nervous system and solely by reciprocal changes in the generation of G3P via glycolysis and via glyceroneogenesis, with no participation of direct phosphorylation of glycerol by GyK.

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Vitamin B-6 restriction impairs fatty acid synthesis in cultured human hepatoma (HepG2) cells

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00359.2012 ◽

2013 ◽

Vol 304 (4) ◽

pp. E342-E351 ◽

Cited By ~ 9

Author(s):

Mei Zhao ◽

Maria A. Ralat ◽

Vanessa da Silva ◽

Timothy J. Garrett ◽

Stephan Melnyk ◽

...

Keyword(s):

Arachidonic Acid ◽

Fatty Acid ◽

Fatty Acid Synthesis ◽

Hepg2 Cells ◽

Metabolic Flux ◽

Pyridoxal Phosphate ◽

Acid Synthesis ◽

Synthesis Rate ◽

Vitamin B ◽

Fatty Acid Profiles

Vitamin B-6 deficiency has been reported to alter n-6 and n-3 fatty acid profiles in plasma and tissue lipids; however, the mechanisms underlying such metabolic changes remain unclear. The objective of this study was to determine the effects of vitamin B-6 restriction on fatty acid profiles and fatty acid synthesis in HepG2 cells. Cells were cultured for 6 wk in media with four different vitamin B-6 concentrations (10, 20, 50, and 2,000 nM added pyridoxal, representing deficient, marginal, adequate, and supraphysiological conditions) that induced a range of steady-state cellular concentrations of pyridoxal phosphate. Total cellular lipid content was greatest in the deficient (10 nM pyridoxal) medium. The percentage of arachidonic acid and the ratio of arachidonic acid to linoleic acid in the total lipid fraction were ∼15% lower in vitamin B-6-restricted cells, which suggests that vitamin B-6 restriction affects n-6 fatty acid interconversions. Metabolic flux studies indicated significantly lower fractional synthesis rate of oleic acid and arachidonic acid at 10, 20, and 50 nM pyridoxal, whereas that of eicosapentaenoic acid was lower in the cells cultured in 10 nM pyridoxal. Additionally, relative mRNA expressions of Δ5 and Δ6 desaturases were 40–50% lower in vitamin B-6-restricted cells. Overall, these findings suggest that vitamin B-6 restriction alters unsaturated fatty acid synthesis, particularly n-6 and n-3 polyunsaturated fatty acid synthesis. These results and observations of changes in human plasma fatty acid profiles caused by vitamin B-6 restriction suggest a mechanism by which vitamin B-6 inadequacy influences the cardiovascular risk.

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Reciprocal responses to dietary diacylglycerol of hepatic enzymes of fatty acid synthesis and oxidation in the rat

British Journal Of Nutrition ◽

10.1079/bjn19970013 ◽

1997 ◽

Vol 77 (1) ◽

pp. 107-121 ◽

Cited By ~ 105

Author(s):

Masakazu Murata ◽

Takashi Ide ◽

Kenji Hara

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Synthesis ◽

Fatty Acid Content ◽

Fatty Acid Synthetase ◽

Acid Synthesis ◽

Dietary Lipids ◽

Hepatic Enzymes ◽

Oxidation Rates ◽

Total Fatty Acids

The activities of hepatic enzymes of fatty acid synthesis and oxidation were compared in rats fed on diacylglycerol and triacylglycerol. In the first trial, rats were fed on diacylglycerol or triacylglycerol (rapeseed oil) for 14 d. The diacylglycerol preparation contained 65·2 g and 32·6 g fatty acids/100 g total fatty acids as 1,3-species and 1,2-species respectively. Fatty acid compositions of these dietary lipids were similar. Dietary acylglycerols were added to experimental diets to provide the same amounts of fatty acids (93·9 g/kg diet). Dietary diacylglycerol compared with triacylglycerol significantly reduced the concentrations of serum and liver triacylglycerol. The activities of enzymes of fatty acid synthesis (fatty acid synthetase, glucose 6-phosphate dehydrogenase (EC 1.1.1.49) and malic enzyme (EC 1.1.1.40)) were significantly lower in rats fed on diacylglycerol than in those fed on triacylglycerol. In contrast, the rates of mitochondrial and peroxisomal oxidation of palmitoyl-CoA in liver homogenates were higher in rats fed on diacylglycerol than in those fed on triacylglycerol. In the second trial, varying amounts of dietary triacylglycerol were replaced by diacylglycerol while the dietary fatty acid content was maintained (93·9 g/kg diet). After 21 d of the feeding period the significant reductions in serum and liver triacylglycerol levels were confirmed in groups of rats fed on the diets in which diacylglycerol supplied more than 65·8 g fatty acids/kg diet (65·8 and 93·9 g/kg). Reductions in the activities of enzymes of fatty acid synthesis and increases in palmitoyl-CoA oxidation rates by both mitochondrial and peroxisomal pathways were also apparent when diacylglycerol replaced triacylglycerol in diets to supply more than 65·8 g fatty acid/kg. Increasing dietary levels of diacylglycerol also progressively increased the activities of enzymes involved in the β-oxidation pathway (carnitine palmitoyltransferase (EC 2.3.1.21), acyl-CoA dehydrogenase (EC 1.3.99.3), acyl-CoA oxidase (EC 1.3.3.6), enoyl-CoA hydratase (EC 4.2.1.17), 3-hydroxyacyl-CoA dehydrogenase (EC 1.1.1.35), 2,4-dienoyl-CoA reductase (EC 1.3.1.34) and Δ3,Δ2-enoyl-CoA isomerase (EC 5.3.3.8)) in the liver. These results suggest that alteration of fatty acid metabolism in the liver is a factor responsible for the serum triacylglycerol-lowering effect of dietary diacylglycerol.

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Effect of light intensity on the ultrastructure of the filamentous cyanobacterium, Anabaena variabilis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103565 ◽

1988 ◽

Vol 46 ◽

pp. 300-301

Author(s):

C. S. Bricker ◽

S. R. Barnum ◽

B. Huang ◽

J. G. Jaworskl

Keyword(s):

Fatty Acid ◽

Light Intensity ◽

Acid Content ◽

Fatty Acid Content ◽

Anabaena Variabilis ◽

Chloroplast Envelope ◽

Major Constituent ◽

Filamentous Cyanobacterium ◽

Photosynthetic Membrane ◽

Effect Of Light

Cyanobacteria are Gram negative prokaryotes that are capable of oxygenic photosynthesis. Although there are many similarities between eukaryotes and cyanobacteria in electron transfer and phosphorylation during photosynthesis, there are two features of the photosynthetic apparatus in cyanobacteria which distinguishes them from plants. Cyanobacteria contain phycobiliproteins organized in phycobilisomes on the surface of photosynthetic membrane. Another difference is in the organization of the photosynthetic membranes. Instead of stacked thylakolds within a chloroplast envelope membrane, as seen In eukaryotes, IntracytopIasmlc membranes generally are arranged in three to six concentric layers. Environmental factors such as temperature, nutrition and light fluency can significantly affect the physiology and morphology of cells. The effect of light Intensity shifts on the ultrastructure of Internal membrane in Anabaena variabilis grown under controlled environmental conditions was examined. Since a major constituent of cyanobacterial thylakolds are lipids, the fatty acid content also was measured and correlated with uItrastructural changes. The regulation of fatty acid synthesis in cyanobacteria ultimately can be studied if the fatty acid content can be manipulated.

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