scholarly journals Nuclear protein kinase activity in glucagon-stimulated perfused rat livers

1974 ◽  
Vol 143 (2) ◽  
pp. 469-471 ◽  
Author(s):  
Warren K. Palmer ◽  
Monique Castagna ◽  
Donal A. Walsh
Keyword(s):  
Enzyme Activity ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Kinase Activity ◽  
Nuclear Protein ◽  
Regulatory Subunit ◽  
Protein Kinase Activity ◽  
Heat Stable ◽  
Rat Livers

Nuclei isolated from glucagon-stimulated perfused rat livers contained 2–3 times as much protein kinase activity as did nuclei from control animals. In the presence of either the heat-stable inhibitor or the protein kinase regulatory subunit the elevated cyclic AMP-independent enzyme activity from stimulated nuclei was inhibited to an activity equivalent to that found in controls.

Regulation of protein kinase by vasopressin in renal medulla in situ

1977 ◽  
Vol 232 (1) ◽  
pp. F50-F57
Author(s):  
T. P. Dousa ◽  
L. D. Barnes
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Kinase Activity ◽  
Kinase Inhibitor ◽  
Renal Medulla ◽  
Protein Kinase Activity ◽  
Kinase Activation ◽  
Heat Stable ◽  
Protein Kinase Activation ◽  
Heat Stable Protein

Results of this study demonstrate that vasopressin activates protein kinase in intact renal medullary cells as detected by measurement of the (-cyclic AMP/+cyclic AMP) protein kinase activity ratios in freshly prepared tissue extracts (40,000 X g supernates) from bovine renal medullary slices. The activation of protein kinase was specific for vasopressin since parathyroid hormone, histamine, angiotensin II, or the inactive analog of vasopressin did not activate protein kinase. There was a direct correlation between the extent of protein kinase activation and the elevation in tissue levels of cyclic AMP elicited by increasing doses of vasopressin or with an increase in incubation time. The elevation of tissue cyclic AMP level and maximum activation of protein kinase reached maximum level at a vasopressin concentration of about 2 X 10(-9) M. Incubation of slices with vasopressin caused a dose-dependent decrease in the cyclic AMP-dependent protein kinase activity in the 40,000 X g supernate of homogenate from the renal medullary slices. This effect of vasopressin was specific for protein kinase since activity of lactate dehydrogenase or a specific [3H]colchicine-binding activity was not affected, and the decrease in the protein kinase was not due to the accumulation of a heat-stable protein kinase inhibitor. There was an increase in protein kinase was not due to the accumulation of a heat-stable protein kinase inhibitor. There was an increase in protein kinase activity extracted from 40,000 X g pellets of homogenate prepared from slices exposed to vasopressin. Results thus provide evidence that cyclic AMP-mediated protein kinase activation in the intact cells is an integral part of cellular response of the mammalian renal medulla to vasopressin.

scholarly journals Purification and properties of a nuclear protein kinase from rat mammary gland

1977 ◽  
Vol 165 (3) ◽  
pp. 469-477 ◽  
Author(s):  
Gopal C. Majumder
Keyword(s):  
Mammary Gland ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Nuclear Protein ◽  
Kinase Inhibitor ◽  
Sedimentation Coefficient ◽  
Molecular Size ◽  
Regulatory Subunit ◽  
Heat Stable ◽  
Exclusion Chromatography

A nuclear protein kinase that shows a high degree of substrate specificity for the phosphorylation of the acidic proteins casein, phosvitin and non-histone chromatin proteins, rather than the basic proteins histones and protamine, was partially purified from lactatingrat mammary gland. The enzyme is associated with the acidic protein fraction of chromatin. Nuclear kinase requires Co2+ for activity, and other bivalent cations such as Mg2+ and Mn2+ can substitute partially for Co2+. The kinase is further activates (2–3-fold) by various salts, their concentration for maximum stimulation being: NaCl, 150mm; KCl, 200mm; sodium acetate, 300mm. The sedimentation coefficient of the nuclear kinase is 8.9S and its mol.wt. is approx. 300000 by gel-exclusion chromatography. The enzyme is not activated by cyclic AMP or cyclic GMP and is inhibited neither by the regulatory subunit of mammary cyclic AMP-dependent protein kinase nor by the heat-stable protein kinase inhibitor from ox heart. Analysis of 32P-labelled protein products reveals that the kinase transfers the terminal phosphate of ATP to serine and threonine residues of proteins. The enzyme, however, has specificity for the phosphorylation of threonine in casein and serine in phosvitin. Molecular size and enzymic characteristics of the nuclear protein kinase are clearly different from those of the cytosol enzyme previously characterized.

scholarly journals Evidence for Ecto-Protein Kinase Activity That Phosphorylates Kemptide in a Cyclic AMP-dependent Mode

1989 ◽  
Vol 264 (24) ◽  
pp. 14549-14555 ◽  
Author(s):  
D Kübler ◽  
W Pyerin ◽  
O Bill ◽  
A Hotz ◽  
J Sonka ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Kinase Activity ◽  
Protein Kinase Activity

scholarly journals The role of protein kinase activation in the control of steroidogenesis by adrenocorticotrophic hormone in the adrenal cortex

1973 ◽  
Vol 136 (4) ◽  
pp. 993-998 ◽  
Author(s):  
Malcolm C. Richardson ◽  
Dennis Schulster
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Adrenal Cortex ◽  
Kinase Activity ◽  
Protein Kinase Activity ◽  
Adrenocorticotrophic Hormone ◽  
Dependent Protein Kinase ◽  
Kinase Activation ◽  
Protein Kinase Activation ◽  
Dependent Protein

A method has been developed for investigation of the effect of adrenocorticotrophic hormone (ACTH) on the state of activation of a cyclic AMP-dependent protein kinase within cells of the adrenal cortex. Enzyme activity was measured in terms of the quantity of32P transferred from [γ-32P]ATP to histone under conditions in which bound cyclic AMP did not dissociate from the regulatory subunit of the protein kinase ACTH (1×10-2i.u./ml) caused a rapid and complete activation of the cyclic AMP-dependent protein kinase activity within 2min of hormone addition to the isolated cells. In response to a range of ACTH concentrations a sigmoid log dose–response curve for protein kinase activation was obtained, with half-maximal stimulation attained at about 1×10-3i.u./ml. However, some low doses of ACTH that elicited a marked (but submaximal) steroidogenic response failed to cause a clear stimulation of protein kinase activity in isolated adrenal cells. Theophylline (2mm) potentiated the effect of ACTH on protein kinase activity. The results implicate an important role for protein kinase in ACTH action on the adrenocortical cell.

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