Post-translational processing of chicken bone phosphoproteins. Identification of bone (phospho)protein kinase

We have detected a protein kinase which phosphorylates bone phosphoproteins (BPPs) in the detergent extract of the membranous fractions in the periosteal bone strips of 12-day-embryonic-chick tibia. This enzyme, tentatively named BPP kinase, has a catalytic subunit of Mr approximately 39,000, utilizes GTP as well as ATP as a phospho-group donor, is inhibited by 2,3-bisphosphoglycerate and heparin, and is therefore similar to casein kinase II. The enzyme can phosphorylate dephosphorylated proteins such as casein, phosvitin and chicken BPPs, but the last-named are preferred substrates. The in vitro-phosphorylation-assay products of this enzyme in the extract were indistinguishable on an SDS/polyacrylamide gel from the major [32P]phosphoproteins metabolically labelled in the embryonic-chick bone tissue. The regulatory mechanisms of the phosphorylation process of BPPs by BPP kinase as well as the potential role of this enzyme in mineralization are discussed.

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Potential Role of Calcium/Calmodulin-dependent Protein Kinase II to Angiogenesis Mediated Pathological Changes Seen in Osteoarthritis

Current Angiogenesis ◽

10.2174/2211552803666141110210138 ◽

2015 ◽

Vol 3 (3) ◽

pp. 123-131

Author(s):

Sadaf Ashraf

Keyword(s):

Protein Kinase ◽

Potential Role ◽

Pathological Changes ◽

Dependent Protein Kinase ◽

Calcium Calmodulin Dependent ◽

Protein Kinase Ii ◽

Dependent Protein

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Specificity of the HIV-1 Protease on Substrates Representing the Cleavage Site in the Proximal Zinc-Finger of HIV-1 Nucleocapsid Protein

Viruses ◽

10.3390/v13061092 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1092

Author(s):

János András Mótyán ◽

Márió Miczi ◽

Stephen Oroszlan ◽

József Tőzsér

Keyword(s):

Amino Acid ◽

Zinc Finger ◽

Cleavage Site ◽

Potential Role ◽

Binding Mode ◽

Interaction Energies ◽

Vitro Assay ◽

Hiv 1

To explore the sequence context-dependent nature of the human immunodeficiency virus type 1 (HIV-1) protease’s specificity and to provide a rationale for viral mutagenesis to study the potential role of the nucleocapsid (NC) processing in HIV-1 replication, synthetic oligopeptide substrates representing the wild-type and modified versions of the proximal cleavage site of HIV-1 NC were assayed as substrates of the HIV-1 protease (PR). The S1′ substrate binding site of HIV-1 PR was studied by an in vitro assay using KIVKCF↓NCGK decapeptides having amino acid substitutions of N17 residue of the cleavage site of the first zinc-finger domain, and in silico calculations were also performed to investigate amino acid preferences of S1′ site. Second site substitutions have also been designed to produce “revertant” substrates and convert a non-hydrolysable sequence (having glycine in place of N17) to a substrate. The specificity constants obtained for peptides containing non-charged P1′ substitutions correlated well with the residue volume, while the correlation with the calculated interaction energies showed the importance of hydrophobicity: interaction energies with polar residues were related to substantially lower specificity constants. Cleavable “revertants” showed one residue shift of cleavage position due to an alternative productive binding mode, and surprisingly, a double cleavage of a substrate was also observed. The results revealed the importance of alternative binding possibilities of substrates into the HIV-1 PR. The introduction of the “revertant” mutations into infectious virus clones may provide further insights into the potential role of NC processing in the early phase of the viral life-cycle.

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Activity, expression and function of a second Drosophila protein kinase A catalytic subunit gene.

Genetics ◽

10.1093/genetics/141.4.1507 ◽

1995 ◽

Vol 141 (4) ◽

pp. 1507-1520 ◽

Cited By ~ 5

Author(s):

A Meléndez ◽

W Li ◽

D Kalderon

Keyword(s):

Protein Kinase ◽

Protein Kinase A ◽

Essential Gene ◽

Sequence Similarity ◽

Catalytic Subunit ◽

Subunit Gene ◽

Drosophila Protein ◽

Pka Catalytic Subunit ◽

Kinase A

Abstract The DC2 gene was isolated previously on the basis of sequence similarity to DC0, the major Drosophila protein kinase A (PKA) catalytic subunit gene. We show here that the 67-kD Drosophila DC2 protein behaves as a PKA catalytic subunit in vitro. DC2 is transcribed in mesodermal anlagen of early embryos. This expression depends on dorsal but on neither twist nor snail activity. DC2 transcriptional fusions mimic this embryonic expression and are also expressed in subsets of cells in the optic lamina, wing disc and leg discs of third instar larvae. A saturation screen of a small deficiency interval containing DC2 for recessive lethal mutations yielded no DC2 alleles. We therefore isolated new deficiencies to generate deficiency trans-heterozygotes that lacked DC2 activity. These animals were viable and fertile. The absence of DC2 did not affect the viability or phenotype of imaginal disc cells lacking DC0 activity or embryonic hatching of animals with reduced DC0 activity. Furthermore, transgenes expressing DC2 from a DC0 promoter did not efficiently rescue a variety of DC0 mutant phenotypes. These observations indicate that DC2 is not an essential gene and is unlikely to be functionally redundant with DC0, which has multiple unique functions during development.

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The in vitro phosphorylation of chromatin by the catalytic subunit of cAMP-dependent protein kinase.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(20)65104-3 ◽

1982 ◽

Vol 257 (11) ◽

pp. 6056-6063 ◽

Cited By ~ 1

Author(s):

S S Taylor

Keyword(s):

Protein Kinase ◽

Catalytic Subunit ◽

Dependent Protein Kinase ◽

Camp Dependent Protein Kinase ◽

Dependent Protein

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The catalytic subunit of protein kinase CK2 phosphorylates in vitro the movement protein of Tomato mosaic virus

Journal of General Virology ◽

10.1099/vir.0.18839-0 ◽

2003 ◽

Vol 84 (2) ◽

pp. 497-505 ◽

Cited By ~ 30

Author(s):

Yasuhiko Matsushita ◽

Mayumi Ohshima ◽

Kuniaki Yoshioka ◽

Masamichi Nishiguchi ◽

Hiroshi Nyunoya

Keyword(s):

Protein Kinase ◽

Mosaic Virus ◽

Protein Kinase Ck2 ◽

Movement Protein ◽

Catalytic Subunit ◽

Tomato Mosaic Virus ◽

Kinase Ck2

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Cyclic AMP-dependent protein kinase regulates transcription of the phosphoenolpyruvate carboxykinase gene but not binding of nuclear factors to the cyclic AMP regulatory element.

Molecular and Cellular Biology ◽

10.1128/mcb.10.7.3357 ◽

1990 ◽

Vol 10 (7) ◽

pp. 3357-3364 ◽

Cited By ~ 60

Author(s):

P G Quinn ◽

D K Granner

Keyword(s):

Protein Kinase ◽

Cyclic Amp ◽

Rat Liver ◽

Phosphoenolpyruvate Carboxykinase ◽

Nuclear Extract ◽

In Vitro Transcription ◽

Catalytic Subunit ◽

Nuclear Factors ◽

Dependent Protein

We have examined the binding of factors in rat liver nuclear extracts to the phosphoenolpyruvate carboxykinase (PEPCK) gene cyclic AMP (cAMP) response element (CRE) and other CREs and have isolated a rat liver CRE-binding protein (CREBP) cDNA. In addition, we have examined the influence of altering the phosphorylation state of nuclear factors on both CRE binding and in vitro transcription. Specific binding to the PEPCK CRE was measured in a mobility shift assay. CRE sequences of the PEPCK, somatostatin, and glycoprotein hormone alpha subunit genes competed equally for binding of rat liver nuclear factors to the PEPCK CRE, whereas mutant PEPCK CRE sequences did not compete for binding. Oligonucleotides complementary to rat pheochromocytoma CREBP (Gonzalez et al., Nature [London] 337:749-752, 1989) were used to prime rat liver and brain cDNA in the polymerase chain reaction. The predominant CREBP molecule obtained was identical to the rat pheochromocytoma CREBP except for a 14-amino-acid deletion in the N-terminal half that was also present in a human placental cDNA (Hoeffler et al., Science 242:1430-1433, 1988). The regulation of transcription by cAMP was examined by coincubation of rat liver nuclear extract with the purified catalytic subunit of cAMP-dependent protein kinase (protein kinase A). Although binding to the CRE was unaffected, in vitro transcription directed by the PEPCK promoter was stimulated by catalytic subunit, and this effect was blocked by protein kinase inhibitor peptide. In contrast, when nuclear extract was coincubated with phosphatase, there was substantial inhibition of in vitro transcription directed by the PEPCK promoter, but there was no effect on binding to the CRE. The major effects of catalytic subunit were exerted through the CRE, but residual stimulation was evident in promoter fragments containing only the TATA element. These data suggest that factors are bound to the CRE at constitutively high levels and that their capacity for transcriptional activation is regulated by phosphorylation.

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Potential Role of Rho-Associated Protein Kinase Inhibitors for Glaucoma Treatment

Recent Patents on Endocrine Metabolic & Immune Drug Discovery ◽

10.2174/187221412800604554 ◽

2012 ◽

Vol 6 (2) ◽

pp. 89-98 ◽

Cited By ~ 8

Author(s):

Basilio Colligris ◽

Almudena Crooke ◽

Fernando Huete ◽

Jesus Pintor

Keyword(s):

Protein Kinase ◽

Potential Role ◽

Kinase Inhibitors ◽

Protein Kinase Inhibitors ◽

Glaucoma Treatment

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The pathophysiologic role of the protein kinase Cδ pathway in the intervertebral discs of rabbits and mice: In vitro, ex vivo, and in vivo studies

Arthritis & Rheumatism ◽

10.1002/art.34337 ◽

2012 ◽

Vol 64 (6) ◽

pp. 1950-1959 ◽

Cited By ~ 25

Author(s):

Michael B. Ellman ◽

Jae-Sung Kim ◽

Howard S. An ◽

Jeffrey S. Kroin ◽

Xin Li ◽

...

Keyword(s):

Protein Kinase ◽

Ex Vivo ◽

Intervertebral Discs ◽

In Vivo Studies ◽

Protein Kinase Cδ

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Requirement of mosXe protein kinase for meiotic maturation of Xenopus oocytes induced by a cdc2 mutant lacking regulatory phosphorylation sites.

Molecular and Cellular Biology ◽

10.1128/mcb.12.7.3192 ◽

1992 ◽

Vol 12 (7) ◽

pp. 3192-3203 ◽

Cited By ~ 22

Author(s):

K M Pickham ◽

A N Meyer ◽

J Li ◽

D J Donoghue

Keyword(s):

Protein Kinase ◽

Oocyte Maturation ◽

Xenopus Oocytes ◽

Germinal Vesicle ◽

Cyclin B1 ◽

Phosphorylation Sites ◽

Germinal Vesicle Breakdown ◽

Regulatory Phosphorylation

The p34cdc2 protein kinase is a component of maturation-promoting factor, the master regulator of the cell cycle in all eukaryotes. The activity of p34cdc2 is itself tightly regulated by phosphorylation and dephosphorylation. Predicted regulatory phosphorylation sites of Xenopus p34cdc2 were mutated in vitro, and in vitro-transcribed RNAs were injected into Xenopus oocytes. The cdc2 single mutants Thr-14----Ala and Tyr-15----Phe did not induce germinal vesicle breakdown (BVBD) upon microinjection into oocytes. In contrast, the cdc2 double mutant Ala-14/Phe-15 did induce GVBD. Both the Ala-14 and Ala-14/Phe-15p34cdc2 mutants were shown to coimmunoprecipitate cyclin B1 and to phosphorylate histone H1 in immune complex kinase assays. Microinjection of antisense oligonucleotides to c-mosXe was used to demonstrate the role of mos protein synthesis in the induction of GVBD by the Ala-14/Phe-15 cdc2 mutant. Thr-161 was also mutated. p34cdc2 single mutants Ala-161 and Glu-161 and triple mutants Ala-14/Phe-15/Ala-161 and Ala-14/Phe-15/Glu-161 failed to induce GVBD in oocytes and showed a decreased binding to cyclin B1 in coimmunoprecipitations. Each of the cdc2 mutants was also assayed by coinjection with cyclin B1 or c-mosXe RNA into oocytes. Several of the cdc2 mutants were found to affect the kinetics of cyclin B1 and/or mos-induced GVBD upon coinjection, although none affected the rate of progesterone-induced maturation. We demonstrate here the significance of Thr-14, Tyr-15, and Thr-161 of p34cdc2 in Xenopus oocyte maturation. In addition, these results suggest a regulatory role for mosXe in induction of oocyte maturation by the cdc2 mutant Ala-14/Phe-15.

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