Involvement of Cyclic AMP-Dependent Protein Kinase on the Phosphorylase Kinase Inhibition by Glucose-6-Phosphate in Adipose Tissue Extracts

1986 ◽  
Vol 18 (01) ◽  
pp. 18-21
Author(s):  
G. Ruiz ◽  
F. Sobrino ◽  
B. Roca ◽  
R. Goberna
Keyword(s):  
Adipose Tissue ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Phosphorylase Kinase ◽  
Dependent Protein Kinase ◽  
Kinase Inhibition ◽  
Tissue Extracts ◽  
Dependent Protein

scholarly journals The phosphorylation of troponin I from cardiac muscle

1975 ◽  
Vol 149 (3) ◽  
pp. 525-533 ◽  
Author(s):  
H A Cole ◽  
S V Perry
Keyword(s):  
Skeletal Muscle ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Cardiac Muscle ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Cardiac Troponin I ◽  
Phosphorylase Kinase ◽  
Dependent Protein Kinase ◽  
Dependent Protein

1. Troponin I isolated from fresh cardiac muscle by affinity chromatography contains about 1.9 mol of covalently bound phosphate/mol. Similar preparations of white-skeletal-muscle troponin I contain about 0.5 mol of phosphate/mol. 2. A 3':5'-cyclic AMP-dependent protein kinase and a protein phosphatase are associated with troponin isolated from cardiac muscle. 3. Bovine cardiac 3':5'-cyclic AMP-dependent protein kinase catalyses the phosphorylation of cardiac troponin I 30 times faster than white-skeletal-muscle troponin I. 4. Troponin I is the only component of cardiac troponin phosphorylated at a significant rate by the endogenous or a bovine cardiac 3':5'-cyclic AMP-dependent protein kinase. 5. Phosphorylase kinase catalyses the phosphorylation of cardiac troponin I at similar or slightly faster rates than white-skeletal-muscle troponin I. 6. Troponin C inhibits the phosphorylation of cardiac and skeletal troponin I catalysed by phosphorylase kinase and the phosphorylation of white skeletal troponin I catalysed by 3':5'-cyclic AMP-dependent protein kinase; the phosphorylation of cardiac troponin I catalysed by the latter enzyme is not inhibited.

scholarly journals Phosphorylation of the inhibitory subunit of troponin in perfused hearts of mice deficient in phosphorylase kinase. Evidence for the phosphorylation of troponin by adenosine 3′:5′-phosphate-dependent protein kinase in vivo

1977 ◽  
Vol 168 (2) ◽  
pp. 307-310 ◽  
Author(s):  
P J England
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Kinase Activity ◽  
Troponin I ◽  
Protein Kinase Activity ◽  
Phosphorylase Kinase ◽  
Dependent Protein Kinase ◽  
Parallel Increase ◽  
Dependent Protein

When hearts from control and phosphorylase kinase-deficient (I strain) mice were perfused with 0.1 micrometer-DL-isoprenaline, there was a parallel increase in contraction, cyclic AMP concentration and troponin I phosphorylation. However, there was no increase in phosphorylase a in the I-strain hearts, whereas the control hearts showed a large increase. Assays of I-strain heart extracts showed a normal cyclic AMP-dependent protein kinase activity but no phosphorylase kinase activity. It is concluded that troponin I is phosphorylated in intact hearts by protein kinase and not phosphorylase kinase.

scholarly journals Rat adipose-tissue glycerol phosphate acyltransferase can be inactivated by cyclic AMP-dependent protein kinase

1978 ◽  
Vol 176 (2) ◽  
pp. 607-610 ◽  
Author(s):  
H G Nimmo ◽  
B Houston
Keyword(s):  
Alkaline Phosphatase ◽  
Adipose Tissue ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Hormonal Control ◽  
Glycerol Phosphate ◽  
Dependent Protein Kinase ◽  
Phosphorylation Reaction ◽  
Dependent Protein ◽  
Rat Adipose Tissue

Rat adipose-tissue glycerol phosphate acyltransferase can be inactivated in a phosphorylation reaction catalysed by cyclic AMP-dependent protein kinase and reactivated by treatment with alkaline phosphatase. These results suggest that phosphorylation of glycerol phosphate acyltransferase may be involved in the hormonal control of esterification.

scholarly journals Studies of rat adipose-tissue microsomal glycerol phosphate acyltransferase

1984 ◽  
Vol 224 (1) ◽  
pp. 101-108 ◽  
Author(s):  
G A Nimmo ◽  
H G Nimmo
Keyword(s):  
Adipose Tissue ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Microsomal Protein ◽  
Catalytic Subunit ◽  
Glycerol Phosphate ◽  
Dependent Protein Kinase ◽  
Phosphorylated Proteins ◽  
Dependent Protein ◽  
Rat Adipose Tissue

Incubation of rat adipose-tissue microsomal fractions with iodoacetate caused an inactivation of glycerol phosphate acyltransferase that could be prevented by the presence of palmitoyl-CoA. A microsomal protein of subunit Mr 54 000 was found to react with radioactively labelled iodoacetate in the absence, but not in the presence, of palmitoyl-CoA. It is suggested that this protein is a component of glycerol phosphate acyltransferase. Incubation of rat adipose-tissue microsomal fractions with the catalytic subunit of cyclic AMP-dependent protein kinase, ATP and Mg2+ caused an inactivation of glycerol phosphate acyltransferase whose magnitude depended on the conditions used for assay of the acyltransferase. Rat adipose tissue microsomal proteins were phosphorylated by using protein kinase and [gamma-32P]ATP. One of the phosphorylated proteins was very similar, but not identical, in mobility to the Mr-54 000 protein labelled by iodoacetate. In contrast with a previous report [Sooranna & Saggerson (1976) FEBS Lett. 64, 36-39], no changes could be detected in the activity of glycerol phosphate acyltransferase in adipocytes treated with adrenaline. Adipocytes were labelled with [32P]Pi and treated with adrenaline, but no 32P was incorporated into the Mr-54000 protein labelled by iodoacetate. The results suggest that the activity of adipose-tissue microsomal glycerol phosphate acyltransferase is not directly controlled by phosphorylation.

scholarly journals β-adrenergic agents increase the phosphorylation of phosphofructokinase in isolated rat epididymal white adipose tissue

1985 ◽  
Vol 232 (3) ◽  
pp. 905-910 ◽  
Author(s):  
E M Sale ◽  
R M Denton
Keyword(s):  
Adipose Tissue ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
White Adipose Tissue ◽  
Beta Agonist ◽  
Dependent Protein Kinase ◽  
Interscapular Brown Adipose Tissue ◽  
Adrenergic Agents ◽  
Dependent Protein ◽  
Epididymal White Adipose Tissue

Pieces of rat epididymal adipose tissue were incubated in medium containing [32P]phosphate for 2 h to achieve steady-state labelling of intracellular phosphoproteins and then with or without hormones for a further 15 min. Phosphofructokinase was rapidly isolated from the tissue by use of either Blue Dextran-Sepharose chromatography or immunoprecipitation with antisera raised against phosphofructokinase purified from rat interscapular brown adipose tissue. Similar extents of incorporation of 32P into phosphofructokinase were measured by both techniques. Exposure of the tissue to adrenaline or the beta-agonist isoprenaline increased phosphorylation by about 5-fold (to about 1.4 mol of phosphate/mol of enzyme tetramer). No change in phosphorylation was detected with the alpha-agonist phenylephrine, but exposure to insulin resulted in an approx. 2-fold increase. The increased phosphorylation observed with isoprenaline was found to be associated with a decrease in the apparent Ka for fructose 2,6-bisphosphate similar to that observed on phosphorylation of phosphofructokinase purified from rat epididymal white adipose tissue with the catalytic subunit of cyclic AMP-dependent protein kinase. These results support the view [Sale & Denton (1985) Biochem. J. 232, 897-904] that an increase in cyclic AMP in adipose tissue may result in an increase in glycolysis through the phosphorylation of phosphofructokinase by cyclic AMP-dependent protein kinase.

Sign in / Sign up

Export Citation Format

Share Document