scholarly journals Light-dependent changes in redox status of the plastidic acetyl-CoA carboxylase and its regulatory component

1999 ◽  
Vol 339 (3) ◽  
pp. 541-546 ◽  
Author(s):  
Akiko KOZAKI ◽  
Yukiko SASAKI
Keyword(s):  
Redox Regulation ◽  
Ph Dependence ◽  
Active Form ◽  
Acid Synthesis ◽  
Cysteine Residue ◽  
Biotin Carboxylase ◽  
Acetyl Coa Carboxylase ◽  
Reductive Activation ◽  
Acetyl Coa

Plastidic acetyl-CoA carboxylase (ACCase; EC 6.4.1.2), which catalyses the synthesis of malonyl-CoA and is the regulatory enzyme of fatty acid synthesis, is activated by light, presumably under redox regulation. To obtain evidence of redox regulation in vivo, the activity of ACCase was examined in pea chloroplasts isolated from plants kept in darkness (dark-ACCase) or after exposure to light for 1 h (light-ACCase) in the presence or absence of a thiol-reducing agent, dithiothreitol (DTT). The protein level was similar for light-ACCase and dark-ACCase, but the activity of light-ACCase in the absence of DTT was approx. 3-fold that of dark-ACCase. The light-ACCase and dark-ACCase were activated approx. 2-fold and 6-fold by DTT respectively, indicating that light-ACCase was in a much more reduced, active form than the dark-ACCase. This is the first demonstration of the light-dependent reduction of ACCase in vivo. Measurement of the activities of ACCase, carboxyltransferase and biotin carboxylase in the presence and absence of DTT, and the thiol-oxidizing agent, 5,5ʹ-dithiobis-(2-nitrobenzoic) acid, revealed that the carboxyltransferase reaction, but not the biotin carboxylase reaction, was redox-regulated. The cysteine residue(s) responsible for redox regulation probably reside on the carboxyltransferase component. Measurement of the pH dependence of biotin carboxylase and carboxyltransferase activities in the ACCase suggested that both components affect the activity of ACCase in vivo at a physiological pH range. These results suggest that the activation of ACCase by light is caused partly by the pH-dependent activation of two components and by the reductive activation of carboxyltransferase.

scholarly journals RNA-seq reveals novel mechanistic targets of withaferin A in prostate cancer cells

2020 ◽  
Vol 41 (6) ◽  
pp. 778-789 ◽  
Author(s):  
Su-Hyeong Kim ◽  
Eun-Ryeong Hahm ◽  
Krishna B Singh ◽  
Sruti Shiva ◽  
Jacob Stewart-Ornstein ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Acid Synthesis ◽  
Acetyl Coa Carboxylase ◽  
Rna Seq ◽  
Atp Citrate Lyase ◽  
Acetyl Coa ◽  
Citrate Lyase

Abstract Withaferin A (WA) is a promising phytochemical exhibiting in vitro and in vivo anticancer activities against prostate and other cancers, but the mechanism of its action is not fully understood. In this study, we performed RNA-seq analysis using 22Rv1 human prostate cancer cell line to identify mechanistic targets of WA. Kyoto Encyclopedia of Genes and Genomes pathway analysis of the differentially expressed genes showed most significant enrichment of genes associated with metabolism. These results were validated using LNCaP and 22Rv1 human prostate cancer cells and Hi-Myc transgenic mice as models. The intracellular levels of acetyl-CoA, total free fatty acids and neutral lipids were decreased significantly following WA treatment in both cells, which was accompanied by downregulation of mRNA (confirmed by quantitative reverse transcription-polymerase chain reaction) and protein levels of key fatty acid synthesis enzymes, including ATP citrate lyase, acetyl-CoA carboxylase 1, fatty acid synthase and carnitine palmitoyltransferase 1A. Ectopic expression of c-Myc, but not constitutively active Akt, conferred a marked protection against WA-mediated suppression of acetyl-CoA carboxylase 1 and fatty acid synthase protein expression, and clonogenic cell survival. WA was a superior inhibitor of cell proliferation and fatty acid synthesis in comparison with known modulators of fatty acid metabolism including cerulenin and etomoxir. Intraperitoneal WA administration to Hi-Myc transgenic mice (0.1 mg/mouse, three times/week for 5 weeks) also resulted in a significant decrease in circulating levels of total free fatty acids and phospholipids, and expression of ATP citrate lyase, acetyl-CoA carboxylase 1, fatty acid synthase and carnitine palmitoyltransferase 1A proteins in the prostate in vivo.

scholarly journals Acute effects in vivo of anti-insulin serum on rates of fatty acid synthesis and activities of acetyl-coenzyme A carboxylase and pyruvate dehydrogenase in liver and epididymal adipose tissue of fed rats

1976 ◽  
Vol 160 (2) ◽  
pp. 413-416 ◽  
Author(s):  
D Stansbie ◽  
R W Brownsey ◽  
M Crettaz ◽  
R M Denton
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Pyruvate Dehydrogenase ◽  
Acid Synthesis ◽  
Epididymal Adipose Tissue ◽  
Acetyl Coa Carboxylase ◽  
Acetyl Coa ◽  
Carboxylase Activity

Plasma insulin concentrations in fed rats were altered acutely by administration of glucose or anti-insulin serum. Rates of fatty acid synthesis in adipose tissue and liver were estimated from the incorporation of 3H from 3H2O. In the adipose tissue dehydrogenase and acetyl-CoA carboxylase were evident. In liver, although changes in rates of fatty acid synthesis were found, the initial activity of pyruvate dehydrogenase did not alter, but small parallel changes in acetyl-CoA carboxylase activity were observed.

scholarly journals Evidence that noradrenaline increases pyruvate dehydrogenase activity and decreases acetyl-CoA carboxylase activity in rat interscapular brown adipose tissue in vivo

1985 ◽  
Vol 228 (3) ◽  
pp. 751-755 ◽  
Author(s):  
J M Gibbins ◽  
R M Denton ◽  
J G McCormack
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Pyruvate Dehydrogenase ◽  
Acid Synthesis ◽  
Acetyl Coa Carboxylase ◽  
Acetyl Coa ◽  
Carboxylase Activity ◽  
Interscapular Brown Adipose Tissue ◽  
Brown Adipose

The rate of fatty acid synthesis in interscapular brown adipose tissue of female cold-adapted rats, as measured by the incorporation of 3H from 3H2O into tissue lipid, was decreased by about 70% after injection of noradrenaline. There was a similar decrease in the activity of acetyl-CoA carboxylase. In contrast, the proportion of pyruvate dehydrogenase in its active non-phosphorylated form was greatly increased after injection of noradrenaline. This finding suggests that the oxidation of glucose may be important in noradrenaline-induced thermogenesis in rat brown adipose tissue.

scholarly journals Polymer-protomer transition of acetyl-CoA carboxylase occurs in vivo and varies with nutritional conditions.

1980 ◽  
Vol 255 (21) ◽  
pp. 10033-10035
Author(s):  
B.A. Ashcraft ◽  
W.S. Fillers ◽  
S.L. Augustine ◽  
S.D. Clarke
Keyword(s):  
Acetyl Coa Carboxylase ◽  
Acetyl Coa ◽  
Nutritional Conditions

scholarly journals HFA1 Encoding an Organelle-specific Acetyl-CoA Carboxylase Controls Mitochondrial Fatty Acid Synthesis inSaccharomyces cerevisiae

2004 ◽  
Vol 279 (21) ◽  
pp. 21779-21786 ◽  
Author(s):  
Ursula Hoja ◽  
Sandra Marthol ◽  
Jörg Hofmann ◽  
Sabine Stegner ◽  
Rainer Schulz ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Acetyl Coa Carboxylase ◽  
Acetyl Coa ◽  
Mitochondrial Fatty Acid

scholarly journals Regulation of acetyl-CoA carboxylase in rat mammary gland. Effects of starvation and of insulin and prolactin deficiency on the fraction of the enzyme in the active form in vivo

1982 ◽  
Vol 204 (1) ◽  
pp. 273-280 ◽  
Author(s):  
Elizabeth M. McNeillie ◽  
Victor A. Zammit
Keyword(s):  
Mammary Gland ◽  
Enzyme Activities ◽  
Enzyme Concentration ◽  
Acetyl Coa Carboxylase ◽  
Initial Activity ◽  
Acetyl Coa ◽  
Activity Ratios ◽  
Rat Mammary Gland ◽  
Rate Limiting

The ‘initial’ (I), endogenous phosphatase-activated (A) and citrate-activated (C) activities of acetyl-CoA carboxylase were measured in mammary-gland extracts of pregnant and lactating rats. There was a 10-fold increase in the A and C enzyme activities in the transition from early to peak lactation [cf. data of Mackall & Lane (1977) Biochem. J.162, 635–642], but there was no significant increase in the ratio of the initial activity to the A and C activities of the enzyme. Starvation (24h) or short-term (3h) streptozotocin-induced diabetes both resulted in a 40% decrease in I/A and I/C activity ratios. In starvation this was accompanied by a decrease in the absolute values of the A and C activities such that the initial activity in mammary glands of starved animals was 45% that in glands from fed animals. Insulin treatment of starved or diabetic animals 60min before killing increased the I activity without affecting the A or C enzyme activities. Removal of the pups for 24h from animals in peak lactation (weaning) resulted in a marked but similar decrease in all three activities such that, although the initial activity was only 10% of that in suckled animals, the I/A and I/C activity ratios remained high and unaltered. Inhibition of prolactin secretion by injection of 2-bromo-α-ergocryptine gave qualitatively similar results to those during weaning. Simultaneous administration of ovine prolactin completely prevented the effects of bromoergocryptine. It is suggested that the initial activity of acetyl-CoA carboxylase in rat mammary gland is regulated by at least two parallel mechanisms: (i) an acute regulation of the proportion of the enzyme in the active state and (ii) a longer-term modulation of enzyme concentration in the gland. Insulin appeared to mediate its acute effects through mechanism (i), whereas prolactin had longer-term effects on enzyme concentration in the gland. A comparison of initial enzyme activities (I) obtained in the present study with rates of lipogenesis measured in vivo [Agius & Williamson (1980) Biochem. J.192, 361–364; Munday & Williamson (1981) Biochem. J.196, 831–837] gave good agreement between the two sets of data for all conditions studied except for 24h-starved and streptozotocin-diabetic animals. It is suggested that acetyl-CoA carboxylase activity is rate-limiting for lipogenesis in the mammary gland in normal, fed, suckled or weaned animals but that in starved and short-term diabetic animals changes in the activity of the enzyme by covalent modification alone may not be sufficient to maintain the enzyme in its rate-limiting role.

scholarly journals P5375A default in acetyl-CoA carboxylase phosphorylation increases thrombus growth in vitro and in vivo, and in a collagen-dependent manner

2017 ◽  
Vol 38 (suppl_1) ◽  
Author(s):  
S. Lepropre ◽  
S. Kautbally ◽  
L. Bertrand ◽  
G.R. Steinberg ◽  
B.E. Kemp ◽  
...  
Keyword(s):  
Dependent Manner ◽  
Acetyl Coa Carboxylase ◽  
Acetyl Coa
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