Regulation of rat liver acetyl-CoA carboxylase. Regulation of phosphorylation and inactivation of acetyl-CoA carboxylase by the adenylate energy charge.

A technique is described for the non-recirculating perfusion of inguinal/abdominal mammary tissue in situ in anaesthetized lactating rats. Tissue viability was maintained, without resort to infusion of vasoactive chemicals which may also be effectors of cellular metabolism, for at least 90 min. Total tissue adenine nucleotides (per mg of DNA) were somewhat decreased in perfused relative to non-perfused mammary tissue. DNA content (per g wet wt. of tissue) was diminished after 90 min of perfusion to approx. 65% of its value in control tissue. Adenylate energy-charge ratios were lower in perfused tissue in the absence of hormones than in control tissue. They were increased to control values by the presence of either insulin or isoprenaline in the perfusate. No changes occurred in flow rate of the perfusate that might account for these increases. In mammary tissue perfused without addition of hormones, acetyl-CoA carboxylase activities were similar to those measured in control tissue samples, although activity-ratio measurements implied some increase in the phosphorylation of this enzyme. Insulin or isoprenaline increased the activity of acetyl-CoA carboxylase, especially when this was measured at low concentrations of citrate. Confirming conclusions from previous experiments with mammary acini and explant preparations, insulin activated acetyl-CoA carboxylase in mammary tissue, but inhibition of its activity was not mediated by cyclic AMP.

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Inhibition of rat liver acetyl CoA carboxylase by chloride

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)39802-3 ◽

1980 ◽

Vol 21 (4) ◽

pp. 488-491

Author(s):

J B Allred ◽

K L Roehrig

Keyword(s):

Rat Liver ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa

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Soy Protein Suppresses Gene Expression of Acetyl-CoA Carboxylase Alpha from Promoter PI in Rat Liver

Bioscience Biotechnology and Biochemistry ◽

10.1271/bbb.70.843 ◽

2006 ◽

Vol 70 (4) ◽

pp. 843-849 ◽

Cited By ~ 3

Author(s):

Hisa AOKI ◽

Kumi KIMURA ◽

Kiharu IGARASHI ◽

Asako TAKENAKA

Keyword(s):

Gene Expression ◽

Rat Liver ◽

Soy Protein ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa

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[2] Acetyl-CoA carboxylase from chicken and rat liver

Methods in Enzymology - Lipids ◽

10.1016/s0076-6879(69)14004-5 ◽

1969 ◽

pp. 9-16 ◽

Cited By ~ 12

Author(s):

Shosaku Numa

Keyword(s):

Rat Liver ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa

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Induction of fatty acid synthetase and acetyl-CoA carboxylase by isolated rat liver cells

Enzyme Induction and Modulation ◽

10.1007/978-1-4613-3879-6_20 ◽

1983 ◽

pp. 307-325

Author(s):

John W. Porter ◽

Theresa L. Swenson

Keyword(s):

Fatty Acid ◽

Rat Liver ◽

Fatty Acid Synthetase ◽

Liver Cells ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa ◽

Isolated Rat Liver ◽

Rat Liver Cells ◽

Isolated Rat

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Octopus mantle citrate synthase

Canadian Journal of Zoology ◽

10.1139/z76-101 ◽

1976 ◽

Vol 54 (6) ◽

pp. 886-891 ◽

Cited By ~ 4

Author(s):

J. H. A. Fields ◽

H. Guderley ◽

K. B. Storey ◽

P. W. Hochachka

Keyword(s):

Citrate Synthase ◽

Specific Activity ◽

Energy Charge ◽

Krebs Cycle ◽

Fold Increase ◽

Adenylate Energy Charge ◽

Michaelis Constant ◽

Acetyl Coa ◽

Muscle Work ◽

Krebs Cycle Intermediates

Citrate synthase (EC 4.1.3.7) in mantle muscle of the octopus, Octopus cyanea, occurs in relatively low specific activity and is largely independent of pH between 7.5 and 9.0. Catalytic activity is regulated by the adenylate energy charge and by at least two Krebs cycle intermediates, α-ketoglutarate and citrate. Of the adenylates, ATP is by far the most potent inhibitor, at near-physiological concentrations (4 mM), causing almost a 20-fold increase in the Michaelis constant for acetyl-CoA. Citrate and α-ketoglutarate, on the other hand, are competitive with respect to oxaloacetate, rather than acetyl-CoA, and bring about large increases in the Michaelis constant for oxaloacetate. The regulatory properties of citrate synthase allow a curtailment of carbon flow into the Krebs cycle during periods of burst muscle work, when mantle anaerobic glycolysis is strongly activated.

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