Relationship Between RNA Polymerase and Protein Kinase Activities in Rat Mammary Gland Nuclei

1975 ◽  
Vol 53 (5) ◽  
pp. 591-598 ◽  
Author(s):  
P. R. Desjardins ◽  
I. M. Mendelson ◽  
K. M. Anderson
Keyword(s):  
Mammary Gland ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Ammonium Sulfate ◽  
Protein Kinases ◽  
Volume Fraction ◽  
Minor Component ◽  
Void Volume ◽  
Protein Kinase Activity ◽  
Rat Mammary Gland

1. Extracts from rat mammary gland nuclei contain cyclic AMP - independent protein kinases which phosphorylate casein rather than histone.2. A major increase in nuclear protein kinase activity occurred during late pregnancy and was maintained with the onset of lactation.3. Two major peaks of activity were resolved by chromatography of nuclear extracts on DEAE-Sephadex; the first (NI) appeared in the void volume and the second (NII) was eluted by 0.05–0.12 M ammonium sulfate. Several other regions of lesser activity were also present.4. Protein kinases in the cytosol 105 000 × g supernatant, precipitated by 70% ammonium sulfate, dialyzed against buffer, and chromatographed on DEAE-Sephadex, yielded a major peak in the void volume and a minor component at about 0.20 M ammonium sulfate. Both components phosphorylated histone in preference to casein, and this was stimulated by cyclic AMP if histone was the substrate, but only the first (void volume) fraction was cyclic AMP -dependent when casein was used.5. Most of RNA polymerases Ib and II, derived from the nucleolus and nucleoplasm, respectively, appeared in column fractions distinct from those containing the major NI and NII protein kinases.6. Cyclic AMP altered the amount of RNA product synthesized by polymerases Ib and II, but the explanation for this is unknown. Due to their elution profiles and cyclic AMP - independence, protein kinases NI and NII are excluded from playing a catalytic role in these effects; participation of quantitatively minor protein kinases which co-elute with polymerase Ib and II is not yet excluded.

Protein Kinases in Testes of Adult and Prepuberal Rats

1974 ◽  
Vol 52 (7) ◽  
pp. 563-569 ◽  
Author(s):  
E. A. Bernard ◽  
G. F. Wassermann
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Enzymatic Activity ◽  
Protein Kinases ◽  
Kinase Activity ◽  
Seminiferous Tubules ◽  
Interstitial Tissue ◽  
Protein Kinase Activity

Cyclic AMP dependence of protein kinase activity (PrK) in testicular homogenates varies according to the substrate used (histone > casein). The enzymatic activity increased during maturation, notably between 35 and 45 days of age. The increment is higher in isolated seminiferous tubules than in interstitial tissue. Upon centrifugation at pH 4.8, two dissimilar PrK preparations can be obtained. The enzymatic activity of both fractions increased with maturation.

scholarly journals Regulation of acetyl-CoA carboxylase in rat mammary gland. Effects of incubation with Ca2+, Mg2+ and ATP on enzyme activity in tissue extracts

1981 ◽  
Vol 200 (3) ◽  
pp. 639-644 ◽  
Author(s):  
E M McNeillie ◽  
R A Clegg ◽  
V A Zammit
Keyword(s):  
Mammary Gland ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Kinase Inhibitor ◽  
Enzyme Activation ◽  
Acetyl Coa Carboxylase ◽  
Acetyl Coa ◽  
Carboxylase Activity ◽  
Rat Mammary Gland ◽  
Subsequent Activation

1. The effect of preincubation of extracts of lactating rat mammary gland with ATP, Mg2+ and micromolar concentrations of Ca2+ on the activity of acetyl-CoA carboxylase was studied. 2. Both Mg2+ and Ca2+ activated the enzyme. Activation with Mg2+ (5 mM) was larger than that with Ca2+ (calculated free Ca2+ concentration = 20-50 microM), but the activity decreased after reaching a peak. The activation obtained with Ca2+ was stable for up to 180 min. 3. Incubation with Ca2+ and Mg2+ together resulted in an activation that was slightly higher than that with Mg2+ only and was stable (compare the results for Ca2+ alone). 4. Preincubation in the absence of Mg2+, but not in the absence of Ca2+, resulted in the impairment of subsequent activation with either Mg2+ (when preincubation was with Ca2+ alone) or Mg2+ plus Ca2+. 5. KF (50 mM) prevented the activation of acetyl-CoA carboxylase by Ca2+ and Mg2+. 6. MgATP2- reversed (Mg2+ + Ca2+)-mediated activation and decreased the activity of acetyl-CoA carboxylase to about 10% of initial activity. Inhibition by ATP was unaffected by addition of cyclic AMP or cyclic AMP-dependent protein kinase inhibitor. 7. 32P was incorporated into acetyl-CoA carboxylase when incubations were carried out in the presence of [gamma-32P]ATP. Subsequent removal of ATP from the incubation medium resulted in rapid loss of 32P from acetyl-CoA carboxylase. 8. It is suggested that extracts of rat mammary gland contain endogenous protein kinase and phosphatase activities that modulate acetyl-CoA carboxylase activity through reversible phosphorylation and dephosphorylation. The phosphatase activity is sensitive to both Mg2+ and micromolar concentrations of Ca2+, whereas the kinase does not appear to be cyclic AMP-dependent.

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

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 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.

Protein kinase C eta upregulation and secretion during postnatal rat mammary gland differentiation

1998 ◽  
Vol 77 (1) ◽  
pp. 48-59 ◽  
Author(s):  
Patricia A. Masso-Welch ◽  
Gordana Verstovsek ◽  
Kathleen Darcy ◽  
Colleen Tagliarino ◽  
Margot M. Ip
Keyword(s):  
Protein Kinase C ◽  
Mammary Gland ◽  
Protein Kinase ◽  
Kinase C ◽  
Rat Mammary Gland ◽  
Mammary Gland Differentiation
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