Investigations into the regulation of lipid biosynthesis in Brassica napus using antisense down-regulation

2002 ◽  
Vol 30 (6) ◽  
pp. 1056-1058 ◽  
Author(s):  
A. R. Slabas ◽  
A. White ◽  
P. O'Hara ◽  
T. Fawcett
Keyword(s):  
Lipid Metabolism ◽  
Brassica Napus ◽  
Fatty Acid Synthase ◽  
Acyl Carrier Protein ◽  
Type I ◽  
Type Ii ◽  
Acetyl Coa Carboxylase ◽  
Down Regulation ◽  
Carbon Resource ◽  
Cytoplasmic Type

We have generated antisense plants of Brassica napus, targeting either the cytoplasmic Type I acetyl-CoA carboxylase or the β-ketoacyl-acyl carrier protein reductase of the Type II dissociable fatty acid synthase, in order to investigate the importance of these components in regulating lipid metabolism in plants. Using a range of down-regulated plants, it has become clear that down-regulation of these genes also causes down-regulation of other components of lipid metabolism, at the activity, translational and transcriptional levels. These plants exhibit effects, not immediately predicted, on oil yield and carbon resource allocation in seeds.

scholarly journals Drosophila STING protein has a role in lipid metabolism

2021 ◽  
Author(s):  
Katarina Akhmetova ◽  
Maxim Balasov ◽  
Igor Chesnokov
Keyword(s):  
Lipid Metabolism ◽  
Fatty Acid Synthase ◽  
Type I Interferon ◽  
Interferon Response ◽  
Type I ◽  
Acetyl Coa Carboxylase ◽  
Direct Role ◽  
Lipid Metabolism Genes ◽  
And Oxidative Stress

ABSTRACTStimulator of interferon genes (STING) plays an important role in innate immunity by controlling type I interferon response against invaded pathogens. In this work we describe a direct but previously unknown role of STING in lipid metabolism in Drosophila. Flies with STING deletion are sensitive to starvation and oxidative stress, have reduced lipid storage and downregulated expression of lipid metabolism genes. We found that Drosophila STING interacts with lipid synthesizing enzymes acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS). ACC and FAS also interact with each other, indicating that all three proteins may be components of a large multi-enzyme complex. The deletion of Drosophila STING leads to disturbed ACC localization and decreased FAS enzyme activity. Together, our results demonstrate a direct role of STING in lipid metabolism in Drosophila.

scholarly journals Drosophila STING protein has a role in lipid metabolism

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Katarina Akhmetova ◽  
Maxim Balasov ◽  
Igor Chesnokov
Keyword(s):  
Lipid Metabolism ◽  
Fatty Acid Synthase ◽  
Type I Interferon ◽  
Interferon Response ◽  
Type I ◽  
Enzyme Complex ◽  
Acetyl Coa Carboxylase ◽  
Lipid Metabolism Genes ◽  
And Oxidative Stress

Stimulator of interferon genes (STING) plays an important role in innate immunity by controlling type I interferon response against invaded pathogens. In this work, we describe a previously unknown role of STING in lipid metabolism in Drosophila. Flies with STING deletion are sensitive to starvation and oxidative stress, have reduced lipid storage, and downregulated expression of lipid metabolism genes. We found that Drosophila STING interacts with lipid synthesizing enzymes acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN). ACC and FASN also interact with each other, indicating that all three proteins may be components of a large multi-enzyme complex. The deletion of Drosophila STING leads to disturbed ACC localization and decreased FASN enzyme activity. Together, our results demonstrate a previously undescribed role of STING in lipid metabolism in Drosophila.

scholarly journals Biotin carboxyl carrier protein and carboxyltransferase subunits of the multi-subunit form of acetyl-CoA carboxylase from Brassica napus: cloning and analysis of expression during oilseed rape embryogenesis

1996 ◽  
Vol 315 (1) ◽  
pp. 103-112 ◽  
Author(s):  
Kieran M. ELBOROUGH ◽  
Robert WINZ ◽  
Ranjit K. DEKA ◽  
Jonathan E. MARKHAM ◽  
Andrew J. WHITE ◽  
...  
Keyword(s):  
Brassica Napus ◽  
Embryo Development ◽  
Oilseed Rape ◽  
Northern Analysis ◽  
Carrier Protein ◽  
Type I ◽  
Type Ii ◽  
Acetyl Coa Carboxylase ◽  
Acetyl Coa ◽  
Biotin Carboxyl Carrier Protein

In the oilseed rape Brassica napus there are two forms of acetyl-CoA carboxylase (ACCase). As in other dicotyledonous plants there is a type I ACCase, the single polypeptide 220 kDa form, and a type II multi-subunit complex analogous to that of Escherichia coli and Anabaena. This paper describes the cloning and characterization of a plant biotin carboxyl carrier protein (BCCP) from the type II ACCase complex that shows 61% identity/79% similarity with Anabaena BCCP at the amino acid level. Six classes of nuclear encoded oilseed rape BCCP cDNA were cloned, two of which contained the entire coding region. The BCCP sequences allowed the assignment of function to two previously unassigned Arabidopsis expressed sequence tag (EST) sequences. We also report the cloning of a second type II ACCase component from oilseed rape, the β-carboxyltransferase subunit (βCT), which is chloroplast-encoded. Northern analysis showed that although the relative levels of BCCP and βCT mRNA differed between different oilseed rape tissues, their temporal patterns of expression were identical during embryo development. At the protein level, expression of BCCP during embryo development was studied by Western blotting, using affinity-purified anti-biotin polyclonal sera. With this technique a 35 kDa protein thought to be BCCP was shown to reside within the chloroplast. This analysis also permitted us to view the differential expression of several unidentified biotinylated proteins during embryogenesis.

scholarly journals Mechanisms of Transforming Growth Factor-β Receptor Endocytosis and Intracellular Sorting Differ between Fibroblasts and Epithelial Cells

2001 ◽  
Vol 12 (3) ◽  
pp. 675-684 ◽  
Author(s):  
Jules J.E. Doré ◽  
Diying Yao ◽  
Maryanne Edens ◽  
Nandor Garamszegi ◽  
Elizabeth L. Sholl ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epithelial Cells ◽  
Ligand Binding ◽  
Transforming Growth Factor ◽  
Point Mutations ◽  
Type I ◽  
Receptor Complex ◽  
Type Ii ◽  
Down Regulation ◽  
Β Receptor

Transforming growth factor-βs (TGF-β) are multifunctional proteins capable of either stimulating or inhibiting mitosis, depending on the cell type. These diverse cellular responses are caused by stimulating a single receptor complex composed of type I and type II receptors. Using a chimeric receptor model where the granulocyte/monocyte colony-stimulating factor receptor ligand binding domains are fused to the transmembrane and cytoplasmic signaling domains of the TGF-β type I and II receptors, we wished to describe the role(s) of specific amino acid residues in regulating ligand-mediated endocytosis and signaling in fibroblasts and epithelial cells. Specific point mutations were introduced at Y182, T200, and Y249 of the type I receptor and K277 and P525 of the type II receptor. Mutation of either Y182 or Y249, residues within two putative consensus tyrosine-based internalization motifs, had no effect on endocytosis or signaling. This is in contrast to mutation of T200 to valine, which resulted in ablation of signaling in both cell types, while only abolishing receptor down-regulation in fibroblasts. Moreover, in the absence of ligand, both fibroblasts and epithelial cells constitutively internalize and recycle the TGF-β receptor complex back to the plasma membrane. The data indicate fundamental differences between mesenchymal and epithelial cells in endocytic sorting and suggest that ligand binding diverts heteromeric receptors from the default recycling pool to a pathway mediating receptor down-regulation and signaling.

scholarly journals Comprehensive Characterization of Toxoplasma Acyl Coenzyme A-Binding Protein TgACBP2 and Its Critical Role in Parasite Cardiolipin Metabolism

mBio ◽  
2018 ◽  
Vol 9 (5) ◽  
Author(s):  
Yong Fu ◽  
Xia Cui ◽  
Sai Fan ◽  
Jing Liu ◽  
Xiao Zhang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Lipid Metabolism ◽  
Toxoplasma Gondii ◽  
Binding Protein ◽  
Ankyrin Repeat ◽  
Type I ◽  
Type Ii ◽  
Content Type ◽  
High K ◽  
Acyl Coenzyme A

ABSTRACT Acyl coenzyme A (CoA)-binding protein (ACBP) can bind acyl-CoAs with high specificity and affinity, thus playing multiple roles in cellular functions. Mitochondria of the apicomplexan parasite Toxoplasma gondii have emerged as key organelles for lipid metabolism and signaling transduction. However, the rationale for how this parasite utilizes acyl-CoA-binding protein to regulate mitochondrial lipid metabolism remains unclear. Here, we show that an ankyrin repeat-containing protein, TgACBP2, is localized to mitochondria and displays active acyl-CoA-binding activities. Dephosphorylation of TgACBP2 is associated with relocation from the plasma membrane to the mitochondria under conditions of regulation of environmental [K+]. Under high [K+] conditions, loss of ACBP2 induced mitochondrial dysfunction and apoptosis-like cell death. Disruption of ACBP2 caused growth and virulence defects in the type II strain but not in type I parasites. Interestingly, mitochondrial association factor-1 (MAF1)-mediated host mitochondrial association (HMA) restored the growth ability of ACBP2-deficient type II parasites. Lipidomics analysis indicated that ACBP2 plays key roles in the cardiolipin metabolism of type II parasites and that MAF1 expression complemented the lipid metabolism defects of ACBP2-deficient type II parasites. In addition, disruption of ACBP2 caused attenuated virulence of Prugniuad (Pru) parasites for mice. Taking the results collectively, these data indicate that ACBP2 is critical for the growth and virulence of type II parasites and for the growth of type I parasites under high [K+] conditions. IMPORTANCE Toxoplasma gondii is one of the most successful human parasites, infecting nearly one-third of the total world population. T. gondii tachyzoites residing within parasitophorous vacuoles (PVs) can acquire fatty acids both via salvage from host cells and via de novo synthesis pathways for membrane biogenesis. However, although fatty acid fluxes are known to exist in this parasite, how fatty acids flow through Toxoplasma lipid metabolic organelles, especially mitochondria, remains unknown. In this study, we demonstrated that Toxoplasma expresses an active ankyrin repeat containing protein TgACBP2 to coordinate cardiolipin metabolism. Specifically, HMA acquisition resulting from heterologous functional expression of MAF1 rescued growth and lipid metabolism defects in ACBP2-deficient type II parasites, manifesting the complementary role of host mitochondria in parasite cardiolipin metabolism. This work highlights the importance of TgACBP2 in parasite cardiolipin metabolism and provides evidence for metabolic association of host mitochondria with T. gondii.

scholarly journals Gene expression pattern of acetyl-coA carboxylase alpha, fatty acid synthase, and stearoyl-CoA desaturase in pregnant Barki sheep under complete feed deprivation

2019 ◽  
pp. 8-13
Author(s):  
Ahmed El-Sayed ◽  
Ahmed Ateya ◽  
Mohamed Hamed ◽  
Sherif Shoieb ◽  
Hussam Ibrahim ◽  
...  
Keyword(s):  
Gene Expression ◽  
Fatty Acid ◽  
Expression Pattern ◽  
Fatty Acid Synthase ◽  
Mrna Level ◽  
Gene Expression Pattern ◽  
Acetyl Coa Carboxylase ◽  
Down Regulation ◽  
Feed Deprivation ◽  
Stearoyl Coa Desaturase

Objective: To assess the mRNA level of acetyl CoA carboxylase alpha (ACACA), fatty acid synthase (FASN), and stearoyl-CoA desaturase (SCD) by means of real-time PCR in Barki sheep subjected to complete feed deprivation. Design: Controlled study. Animals: Seven healthy pregnant ewes. Procedures: Ewes were subjected to complete feed deprivation with ad libitum water for five consecutive days. Venous blood samples were collected from each ewe before (zero time) and on the fifth day post-deprivation of feed for measurement of the mRNA level of ACACA, FASN, and SCD and assessment of serum metabolic profile parameters. Results: On the fifth day post-fasting, the gene expression pattern of ACACA, FASN, SCD genes showed a significant (p < 0.05) down regulation in comparison with pre-deprivation of feed. There was a significant (p < 0.05) increase in the serum level of non-esterified fatty acids (NEFA), beta-hydroxyl buteric acid (BHBA), and triglycerides in pregnant ewes in the fifth day post-fasting in comparison with pre-deprivation of feed. On the other hand, there was a significant (p < 0.05) decrease in the level of glucose, cholesterol, and insulin in pregnant ewes in the fifth day post-fasting compared with pre-deprivation of feed. On histopathology, liver showed marked heptic steatosis in midzonal and periportal area, with formation of small fatty cysts in liver lobule. There was a positive correlation between leptin and insulin (r = 0.996; p < 0.01), BHB and leptin (r = 0.951; p < 0.05) and glucose and SCD (r = 1.0, p < 0.01). However, there was a negative correlation between FASN and NEFA (r = - 0.991; p < 0.05), FASN and leptin (r = -0.683; p < 0.05) and FASN and cholesterol (r = - 0.82; p < 0.05). Conclusion and clinical relevance: Pregnant Barki ewes can clinically tolerate complete feed deprivation for five days, with down regulation of ACACA, FASN, SCD genes and presence of marked metabolic changes. Therefore, metabolic monitoring is warranted to predict the early changes associated with feed deprivation under different stressful conditions.

scholarly journals A Mammalian Type I Fatty Acid Synthase Acyl Carrier Protein Domain Does Not Sequester Acyl Chains

2007 ◽  
Vol 283 (1) ◽  
pp. 518-528 ◽  
Author(s):  
Eliza Ploskoń ◽  
Christopher J. Arthur ◽  
Simon E. Evans ◽  
Christopher Williams ◽  
John Crosby ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Acyl Carrier Protein ◽  
Protein Domain ◽  
Carrier Protein ◽  
Type I ◽  
Acyl Chains

Acyl carrier protein: structure–function relationships in a conserved multifunctional protein family

2007 ◽  
Vol 85 (6) ◽  
pp. 649-662 ◽  
Author(s):  
David M. Byers ◽  
Huansheng Gong
Keyword(s):  
Fatty Acid ◽  
Active Sites ◽  
Fatty Acid Synthase ◽  
Acyl Carrier Protein ◽  
Divalent Cations ◽  
Structural Features ◽  
Carrier Protein ◽  
Type I ◽  
Prosthetic Group

Acyl carrier protein (ACP) is a universal and highly conserved carrier of acyl intermediates during fatty acid synthesis. In yeast and mammals, ACP exists as a separate domain within a large multifunctional fatty acid synthase polyprotein (type I FAS), whereas it is a small monomeric protein in bacteria and plastids (type II FAS). Bacterial ACPs are also acyl donors for synthesis of a variety of products, including endotoxin and acylated homoserine lactones involved in quorum sensing; the distinct and essential nature of these processes in growth and pathogenesis make ACP-dependent enzymes attractive antimicrobial drug targets. Additionally, ACP homologues are key components in the production of secondary metabolites such as polyketides and nonribosomal peptides. Many ACPs exhibit characteristic structural features of natively unfolded proteins in vitro, with a dynamic and flexible conformation dominated by 3 parallel α helices that enclose the thioester-linked acyl group attached to a phosphopantetheine prosthetic group. ACP conformation may also be influenced by divalent cations and interaction with partner enzymes through its “recognition” helix II, properties that are key to its ability to alternately sequester acyl groups and deliver them to the active sites of ACP-dependent enzymes. This review highlights recent progress in defining how the structural features of ACP are related to its multiple carrier roles in fatty acid metabolism.

scholarly journals Antimycobacterial action of thiolactomycin: an inhibitor of fatty acid and mycolic acid synthesis.

1996 ◽  
Vol 40 (12) ◽  
pp. 2813-2819 ◽  
Author(s):  
R A Slayden ◽  
R E Lee ◽  
J W Armour ◽  
A M Cooper ◽  
I M Orme ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Acyl Carrier Protein ◽  
Mycolic Acid ◽  
Carrier Protein ◽  
Type I ◽  
Dependent Manner ◽  
Fas Ii

Thiolactomycin (TLM) possesses in vivo antimycobacterial activity against the saprophytic strain Mycobacterium smegmatis mc2155 and the virulent strain M. tuberculosis Erdman, resulting in complete inhibition of growth on solid media at 75 and 25 micrograms/ml, respectively. Use of an in vitro murine macrophage model also demonstrated the killing of viable intracellular M. tuberculosis in a dose-dependent manner. Through the use of in vivo [1,2-14C]acetate labeling of M. smegmatis, TLM was shown to inhibit the synthesis of both fatty acids and mycolic acids. However, synthesis of the shorter-chain alpha'-mycolates of M. smegmatis was not inhibited by TLM, whereas synthesis of the characteristic longer-chain alpha-mycolates and epoxymycolates was almost completely inhibited at 75 micrograms/ml. The use of M. smegmatis cell extracts demonstrated that TLM specifically inhibited the mycobacterial acyl carrier protein-dependent type II fatty acid synthase (FAS-II) but not the multifunctional type I fatty acid synthase (FAS-I). In addition, selective inhibition of long-chain mycolate synthesis by TLM was demonstrated in a dose-response manner in purified, cell wall-containing extracts of M. smegmatis cells. The in vivo and in vitro data and knowledge of the mechanism of TLM resistance in Escherichia coli suggest that two distinct TLM targets exist in mycobacteria, the beta-ketoacyl-acyl carrier protein synthases involved in FAS-II and the elongation steps leading to the synthesis of the alpha-mycolates and oxygenated mycolates. The efficacy of TLM against M. smegmatis and M. tuberculosis provides the prospects of identifying fatty acid and mycolic acid biosynthetic genes and revealing a novel range of chemotherapeutic agents directed against M. tuberculosis.

Differential up- and down-regulation of Type I and Type II receptors for adrenocorticosteroid hormones in mouse brain

Steroids ◽  
1989 ◽  
Vol 53 (1-2) ◽  
pp. 59-76 ◽  
Author(s):  
William G. Luttge ◽  
Mary E. Rupp
Keyword(s):  
Mouse Brain ◽  
Type I ◽  
Type Ii ◽  
Down Regulation
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