Phosphorylation of Rat Liver Mitochondrial Glycerol-3-phosphate Acyltransferase by Casein Kinase 2

It was previously reported that the phosphorylation of three proteins of 36, 40 to 42, and 50 kDa by casein kinase 2 is inhibited by calmodulin in nuclear extracts from rat liver cells (R. Bosser, R. Aligué, D. Guerini, N. Agell, E. Carafoli, and O. Bachs, J. Biol. Chem. 268:15477-15483, 1993). By immunoblotting, peptide mapping, and endogenous phosphorylation experiments, the 36- and 40- to 42-kDa proteins have been identified as the A2 and C proteins, respectively, of the heterogeneous nuclear ribonucleoprotein particles. To better understand the mechanism by which calmodulin inhibits the phosphorylation of these proteins, they were purified by using single-stranded DNA chromatography, and the effect of calmodulin on their phosphorylation by casein kinase 2 was analyzed. Results revealed that whereas calmodulin inhibited the phosphorylation of purified A2 and C proteins in a Ca(2+)-dependent manner, it did not affect the casein kinase 2 phosphorylation of a different protein substrate, i.e., beta-casein. These results indicate that the effect of calmodulin was not on casein kinase 2 activity but on specific protein substrates. The finding that the A2 and C proteins can bind to a calmodulin-Sepharose column in a Ca(2+)-dependent manner suggests that this association could prevent the phosphorylation of the proteins by casein kinase 2. Immunoelectron microscopy studies have revealed that such interactions could also occur in vivo, since calmodulin and A2 and C proteins colocalize on the ribonucleoprotein particles in rat liver cell nuclei.

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Specificity determinants of maize casein kinase-IIB are related to but distinct from those of rat liver casein kinase-2

Biochimica et Biophysica Acta (BBA) - Molecular Cell Research ◽

10.1016/0167-4889(89)90173-0 ◽

1989 ◽

Vol 1010 (2) ◽

pp. 274-277 ◽

Cited By ~ 12

Author(s):

Grazyna Dobrowolska ◽

Flavio Meggio ◽

Fernando Marchiori ◽

Lorenzo A. Pinna

Keyword(s):

Rat Liver ◽

Casein Kinase ◽

Casein Kinase 2 ◽

Specificity Determinants

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Effect of starvation, diabetes and insulin on the casein kinase 2 from rat liver cytosol

Biochemical Journal ◽

10.1042/bj2250321 ◽

1985 ◽

Vol 225 (2) ◽

pp. 321-326 ◽

Cited By ~ 16

Author(s):

C Martos ◽

M Plana ◽

M D Guasch ◽

E Itarte

Keyword(s):

Rat Liver ◽

Glycogen Synthase ◽

Gradient Centrifugation ◽

Diabetic Rats ◽

Casein Kinase ◽

Casein Kinase 2 ◽

Partial Purification ◽

Liver Cytosol ◽

Casein Kinases ◽

Rat Liver Cytosol

Starvation, diabetes and insulin did not alter the concentration of casein kinases in rat liver cytosol. However, the Km for casein of casein kinase 2 from diabetic rats was about 2-fold lower than that from control animals. Administration of insulin to control rats did not alter this parameter, but increased the Km for casein of casein kinase 2 in diabetic rats. Starvation did not affect the kinetic constants of casein kinases. The effect of diabetes on casein kinase 2 persisted after partial purification of the enzyme by glycerol-density-gradient centrifugation and affected also its activity on other protein substrates such as phosvitin, high-mobility-group protein 14 and glycogen synthase. The results indicate that rat liver cytosol casein kinase 2 is under physiological control.

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Heterogeneity of rat liver cytosol casein kinase 2. Association between the α/α' -subunits of casein kinase 2 and the phosphorylatable protein pp49

Biochemical Journal ◽

10.1042/bj2770811 ◽

1991 ◽

Vol 277 (3) ◽

pp. 811-818 ◽

Cited By ~ 11

Author(s):

E Molina ◽

M Plana ◽

E Itarte

Keyword(s):

Rat Liver ◽

Casein Kinase ◽

Casein Kinase 2 ◽

Beta Subunit ◽

Kinetic Properties ◽

Liver Cytosol ◽

Alpha Subunits ◽

Beta Casein ◽

Casein Kinases ◽

Rat Liver Cytosol

Casein kinase 2 activity could be resolved into three peaks by chromatography on DEAE-Sepharose. The peak eluted at high salt concentrations (casein kinase 2b) showed molecular and kinetic properties typical of the heterotetramer composed of alpha-(or alpha'-) and beta-subunits. In contrast, the peak that was eluted at low salt concentrations (casein kinase 2a) contained no beta-subunit but a phosphorylatable protein of 49 kDa (pp49), in addition to the alpha/alpha'-subunits. The presence of alpha/alpha'/alpha"-subunits in preparations of casein kinases 2a and 2b was confirmed by immunological assays. Casein kinase 2a had low specific activity and a very high apparent Km for beta-casein. The peak eluted at intermediate ionic strength contained the alpha/alpha'-subunits and variable amounts of beta-subunit and pp49, and had kinetic properties intermediate between those of casein kinases 2a and 2b. Experiments based on heat inactivation, inhibition by low concentrations of heparin and ability to use GTP as substrate suggested that phosphorylation of pp49 was catalysed by the alpha/alpha'-subunits of casein kinase 2. No similarities were observed in the phosphopeptide maps of pp49 and beta-subunit. These results show that the alpha/alpha'-subunits of rat liver cytosol casein kinase 2 can form complexes not only with the beta-subunit but also with pp49, and that the complexes containing pp49 have a reduced affinity for the exogenous protein substrate beta-casein.

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Site specificity of casein kinase-2 (TS) from rat liver cytosol. A study with model peptide substrates

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1986.tb09962.x ◽

1986 ◽

Vol 160 (2) ◽

pp. 239-244 ◽

Cited By ~ 149

Author(s):

Oriano MARIN ◽

Flavio MEGGIO ◽

Fernando MARCHIORI ◽

Gianfranco BORIN ◽

Lorenzo A. PINNA

Keyword(s):

Rat Liver ◽

Casein Kinase ◽

Casein Kinase 2 ◽

Site Specificity ◽

Model Peptide ◽

Peptide Substrates ◽

Liver Cytosol ◽

Rat Liver Cytosol

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Statins as the Controlling Agents for Non-Hodgkin's Lymphomas via Increasing the Casein Kinase 2 Interacting Protein-1: A Hypothesis

Current Drug Discovery Technologies ◽

10.2174/1570163816666190628165200 ◽

2020 ◽

Vol 17 (5) ◽

pp. 616-618

Author(s):

Kimia Kazemi ◽

Negin Mozafari ◽

Hajar Ashrafi ◽

Pedram Rafiei ◽

Amir Azadi

Keyword(s):

Cell Proliferation ◽

Mevalonate Pathway ◽

Casein Kinase ◽

Casein Kinase 2 ◽

Interacting Protein ◽

Akt Phosphorylation ◽

Anticancer Properties ◽

Proliferation And Apoptosis ◽

Cellular Signaling Pathway ◽

Hodgkin's Lymphomas

Background: Non-Hodgkin's lymphomas (NHL), derived from B- or T-cell, consist of a heterogeneous group of malignant lymphoproliferative disorders. Knockdown of Casein kinase 2 interacting protein-1 (CKIP-1) in NHL promoted cell proliferation and inhibited apoptosis via enhancing phosphorylated Protein Kinase B (PKB or AKT) expression. Statins are the class of drugs that inhibit the ratelimiting step of the mevalonate pathway, which is essential for the biosynthesis of various compounds, including cholesterol. Also, statins have anticancer properties being mediated by different mechanisms. Methods: A search on databases like Scopus and PubMed with keywords such as statin and non- Hodgkin's lymphomas was performed and Kyoto Encyclopedia of Genes and Genomes (KEGG) website was used to evaluate and reconfirm the involved cellular signaling pathway. Results: CKIP-1 is involved in the regulation of cell proliferation and apoptosis while plays an important role in many cancers. We can hypothesize that statins may increase the expression levels of CKIP-1 which could contribute to the reductions in phospho-AKT level. Hence, they may ameliorate the NHL patients via suppressing AKT phosphorylation and increasing CKIP- expression. Conclusion: Present review confirms the positive effect of statins on NHL by increasing CKIP-1 and reducing cell proliferation, subsequently.

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Novel Anthraquinone Derivatives as Dual Inhibitors of Topoisomerase 2 and Casein Kinase 2: In Silico Studies, Synthesis and Biological Evaluation on Leukemic Cell Lines

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520618666180423111309 ◽

2019 ◽

Vol 18 (11) ◽

pp. 1551-1562 ◽

Cited By ~ 4

Author(s):

Abbas Kabir ◽

Kalpana Tilekar ◽

Neha Upadhyay ◽

C.S. Ramaa

Keyword(s):

Cell Cycle ◽

Cell Line ◽

Cell Lines ◽

Biological Evaluation ◽

Casein Kinase ◽

Casein Kinase 2 ◽

Cell Cycle Analysis ◽

Protein Targets ◽

Topoisomerase 2 ◽

Dual Inhibitors

Background: Cancer being a complex disease, single targeting agents remain unsuccessful. This calls for “multiple targeting”, wherein a single drug is so designed that it will modulate the activity of multiple protein targets. Topoisomerase 2 (Top2) helps in removing DNA tangles and super-coiling during cellular replication, Casein Kinase 2 (CK2) is involved in the phosphorylation of a multitude of protein targets. Thus, in the present work, we have tried to develop dual inhibitors of Top2 and CK2. Objective: With this view, in the present work, 2 human proteins, Top2 and CK2 have been targeted to achieve the anti-proliferative effects. Methods: Novel 1-acetylamidoanthraquinone (3a-3y) derivatives were designed, synthesized and their structures were elucidated by analytical and spectral characterization techniques (FTIR, 1H NMR, 13C NMR and Mass Spectroscopy). The synthesized compounds were then subjected to evaluation of cytotoxic potential by the Sulforhodamine B (SRB) protein assay, using HL60 and K562 cell lines. Ten compounds were analyzed for Top2, CK2 enzyme inhibitory potential. Further, top three compounds were subjected to cell cycle analysis. Results: The compounds 3a to 3c, 3e, 3f, 3i to 3p, 3t and 3x showed excellent cytotoxic activity to HL-60 cell line indicating their high anti-proliferative potential in AML. The compounds 3a to 3c, 3e, 3f, 3i to 3p and 3y have shown good to moderate activity on K-562 cell line. Compounds 3e, 3f, 3i, 3x and 3y were found more cytotoxic than standard doxorubicin. In cell cycle analysis, the cells (79-85%) were found to arrest in the G0/G1 phase. Conclusion: We have successfully designed, synthesized, purified and structurally characterized 1- acetylamidoanthraquinone derivatives. Even though our compounds need design optimization to further increase enzyme inhibition, their overall anti-proliferative effects were found to be encouraging.

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