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Qiu F, He S, Zhang Z, Dai S, Wang J, Liu N, Li Z, Hu X, Xiang S, Wei C. MiR-93 alleviates DEHP plasticizer-induced neurotoxicity by negatively regulating TNFAIP1 and inhibiting ubiquitin-mediated degradation of CK2β. Food Chem Toxicol 2023:113888. [PMID: 37302538 DOI: 10.1016/j.fct.2023.113888] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/28/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
Di-(2-ethylhexyl) phthalate (DEHP) is a plasticizer that is widely used in various products, such as plastic packaging in food industries. As an environmental endocrine disruptor, it induces adverse effects on brain development and function. However, the molecular mechanisms by which DEHP induces learning and memory impairment remain poorly understood. Herein, we found that DEHP impaired learning and memory in pubertal C57BL/6 mice, decreased the number of neurons, downregulated miR-93 and the β subunit of casein kinase 2 (CK2β), upregulated tumor necrosis factor-induced protein 1 (TNFAIP1), and inhibited Akt/CREB pathway in mouse hippocampi. Coimmunoprecipitation and western blotting assays revealed that TNFAIP1 interacted with CK2β and promoted its degradation by ubiquitination. Bioinformatics analysis showed a miR-93 binding site in the 3'-untranslated region of Tnfaip1. A dual-luciferase reporter assay revealed that miR-93 targeted TNFAIP1 and negatively regulated its expression. MiR-93 overexpression prevented DEHP-induced neurotoxicity by downregulating TNFAIP1 and then activating CK2/Akt/CREB pathway. These data indicate that DEHP upregulates TNFAIP1 expression by downregulating miR-93, thus promoting ubiquitin-mediated degradation of CK2β, subsequently inhibiting Akt/CREB pathway, and finally inducing learning and memory impairment. Therefore, miR-93 can relieve DEHP-induced neurotoxicity and may be used as a potential molecular target for prevention and treatment of related neurological disorders.
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Affiliation(s)
- Feng Qiu
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Simei He
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Zilong Zhang
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Siyu Dai
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Jin Wang
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Ning Liu
- School of Medicine, Hunan Normal University, Changsha, 410013, Hunan, China
| | - Zhiwei Li
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Xiang Hu
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Shuanglin Xiang
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Chenxi Wei
- State Key Laboratory of Developmental Biology of Freshwater Fish, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China; The National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, School of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China.
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Unni P, Friend J, Weinberg J, Okur V, Hochscherf J, Dominguez I. Predictive functional, statistical and structural analysis of CSNK2A1 and CSNK2B variants linked to neurodevelopmental diseases. Front Mol Biosci 2022; 9:851547. [PMID: 36310603 PMCID: PMC9608649 DOI: 10.3389/fmolb.2022.851547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 06/29/2022] [Indexed: 12/02/2022] Open
Abstract
Okur-Chung Neurodevelopmental Syndrome (OCNDS) and Poirier-Bienvenu Neurodevelopmental Syndrome (POBINDS) were recently identified as rare neurodevelopmental disorders. OCNDS and POBINDS are associated with heterozygous mutations in the CSNK2A1 and CSNK2B genes which encode CK2α, a serine/threonine protein kinase, and CK2β, a regulatory protein, respectively, which together can form a tetrameric enzyme called protein kinase CK2. A challenge in OCNDS and POBINDS is to understand the genetic basis of these diseases and the effect of the various CK2⍺ and CK2β mutations. In this study we have collected all variants available to date in CSNK2A1 and CSNK2B, and identified hotspots. We have investigated CK2⍺ and CK2β missense mutations through prediction programs which consider the evolutionary conservation, functionality and structure or these two proteins, compared these results with published experimental data on CK2α and CK2β mutants, and suggested prediction programs that could help predict changes in functionality of CK2α mutants. We also investigated the potential effect of CK2α and CK2β mutations on the 3D structure of the proteins and in their binding to each other. These results indicate that there are functional and structural consequences of mutation of CK2α and CK2β, and provide a rationale for further study of OCNDS and POBINDS-associated mutations. These data contribute to understanding the genetic and functional basis of these diseases, which is needed to identify their underlying mechanisms.
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Affiliation(s)
- Prasida Unni
- Department of Medicine, Boston University School of Medicine and Boston Medical Center, Boston University, Boston, MA, United States
| | - Jack Friend
- Department of Medicine, Boston University School of Medicine and Boston Medical Center, Boston University, Boston, MA, United States
| | - Janice Weinberg
- Department of Biostatistics, Boston University School of Public Health, Boston University, Boston, MA, United States
| | - Volkan Okur
- New York Genome Center, New York, NY, United States
| | - Jennifer Hochscherf
- Department of Chemistry, Institute of Biochemistry, University of Cologne, Cologne, Germany
| | - Isabel Dominguez
- Department of Medicine, Boston University School of Medicine and Boston Medical Center, Boston University, Boston, MA, United States
- *Correspondence: Isabel Dominguez,
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Borgo C, D'Amore C, Cesaro L, Sarno S, Pinna LA, Ruzzene M, Salvi M. How can a traffic light properly work if it is always green? The paradox of CK2 signaling. Crit Rev Biochem Mol Biol 2021; 56:321-359. [PMID: 33843388 DOI: 10.1080/10409238.2021.1908951] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
CK2 is a constitutively active protein kinase that assuring a constant level of phosphorylation to its numerous substrates supports many of the most important biological functions. Nevertheless, its activity has to be controlled and adjusted in order to cope with the varying needs of a cell, and several examples of a fine-tune regulation of its activity have been described. More importantly, aberrant regulation of this enzyme may have pathological consequences, e.g. in cancer, chronic inflammation, neurodegeneration, and viral infection. Our review aims at summarizing our current knowledge about CK2 regulation. In the first part, we have considered the most important stimuli shown to affect protein kinase CK2 activity/expression. In the second part, we focus on the molecular mechanisms by which CK2 can be regulated, discussing controversial aspects and future perspectives.
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Affiliation(s)
- Christian Borgo
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Claudio D'Amore
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Luca Cesaro
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Stefania Sarno
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Lorenzo A Pinna
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,CNR Institute of Neurosciences, Padova, Italy
| | - Maria Ruzzene
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,CNR Institute of Neurosciences, Padova, Italy
| | - Mauro Salvi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
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Feng Q, Huang Y, Yao D, Zhu C, Li S, Ma H, Aweya JJ, Zhang Y. Litopenaeus vannamei CK2 is involved in shrimp innate immunity by modulating hemocytes apoptosis. FISH & SHELLFISH IMMUNOLOGY 2019; 94:643-653. [PMID: 31563555 DOI: 10.1016/j.fsi.2019.09.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/23/2019] [Accepted: 09/25/2019] [Indexed: 06/10/2023]
Abstract
Protein kinase CK2 (CK2) is a ubiquitous serine/threonine kinase with multiple cellular functions in vertebrates including apoptosis, differentiation, proliferation, survival, tumorigenesis, signal transduction, immune regulation and inflammation. In the current study, the catalytic and regulatory subunit homologs of Litopenaeus vannamei protein kinase CK2 (LvCK2α and LvCK2β) were cloned and characterized. LvCK2α has a full-length cDNA sequence of 1764 bp with a 1053 bp open reading frame (ORF) encoding a putative protein of 351 amino acids, which contains a typical serine/threonine kinase domain. On the other hand, LvCK2β has a 1394 bp full-length cDNA with an ORF of 663 bp encoding a protein with 221 amino acids, which contains a Casein kinase II regulatory subunit domain. Sequence and phylogenetic analysis revealed that LvCK2 was evolutionary related with the CK2 of invertebrates. Quantitative reverse transcription PCR (RT-qPCR) analysis showed that LvCK2α and LvCK2β transcripts were widely expressed in all shrimp tissues tested, and were both induced in hemocytes and hepatopancreas upon challenge with Vibrio parahaemolyticus, Streptoccocus iniae, lipopolysaccharide (LPS), and white spot syndrome virus (WSSV), suggesting their involvement in shrimp immune response. Moreover, RNA interference (RNAi) of LvCK2α resulted in increased hemocytes apoptosis, shown by high caspase 3/7 activity, increased number of apoptotic cells, coupled with an elevation in transcript levels of pro-apoptotic LvCaspase3 and LvCytochrome C, and a reduction in mRNA levels of pro-survival LvBcl2, LvIAP1, and LvIAP2. In addition, LvCK2α knockdown followed by V. parahaemolyticus challenge resulted in higher cumulative mortality of shrimp. Taken together, our current findings suggest that LvCK2 modulates shrimp hemocytes apoptosis as part of the innate immune response to pathogens.
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Affiliation(s)
- Qian Feng
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China
| | - Yueqian Huang
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China
| | - Defu Yao
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China
| | - Chunhua Zhu
- College of Fisheries, Guangdong Ocean University, Zhanjiang, 524025, China
| | - Shengkang Li
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China
| | - Hongyu Ma
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China
| | - Jude Juventus Aweya
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China.
| | - Yueling Zhang
- Department of Biology and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China.
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5
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Lolli G, Cozza G, Mazzorana M, Tibaldi E, Cesaro L, Donella-Deana A, Meggio F, Venerando A, Franchin C, Sarno S, Battistutta R, Pinna LA. Inhibition of protein kinase CK2 by flavonoids and tyrphostins. A structural insight. Biochemistry 2012; 51:6097-107. [PMID: 22794353 DOI: 10.1021/bi300531c] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sixteen flavonoids and related compounds have been tested for their ability to inhibit three acidophilic Ser/Thr protein kinases: the Golgi apparatus casein kinase (G-CK) recently identified with protein FAM20C, protein kinase CK1, and protein kinase CK2. While G-CK is entirely insensitive to all compounds up to 40 μM concentration, consistent with the view that it is not a member of the kinome, and CK1 is variably inhibited in an isoform-dependent manner by fisetin and luteolin, and to a lesser extent by myricetin and quercetin, CK2 is susceptible to drastic inhibition by many flavonoids, displaying with six of them IC(50) values < 1 μM. A common denominator of these compounds (myricetin, quercetin, fisetin, kaempferol, luteolin, and apigenin) is a flavone scaffold with at least two hydroxyl groups at positions 7 and 4'. Inhibition is competitive with respect to the phospho-donor substrate ATP. The crystal structure of apigenin and luteolin in complex with the catalytic subunit of Zea mays CK2 has been solved, revealing their ability to interact with both the hinge region (Val116) and the positive area near Lys68 and the conserved water W1, the two main polar ligand anchoring points in the CK2 active site. Modeling experiments account for the observation that luteolin but not apigenin inhibits also CK1. The observation that luteolin shares its pyrocatechol moiety with tyrphostin AG99 prompted us to solve also the structure of this compound in complex with CK2. AG99 was found inside the ATP pocket, consistent with its mode of inhibition competitive with respect to ATP. As in the case of luteolin, the pyrocatechol group of AG99 is critical for binding, interacting with the positive area in the deepest part of the CK2 active site.
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Affiliation(s)
- Graziano Lolli
- Venetian Institute of Molecular Medicine (VIMM), Padova, Italy, Via G. Orus 2 35129 Padova, Italy
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Lolli G, Pinna LA, Battistutta R. Structural determinants of protein kinase CK2 regulation by autoinhibitory polymerization. ACS Chem Biol 2012; 7:1158-63. [PMID: 22506723 DOI: 10.1021/cb300054n] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
CK2 is a Ser/Thr protein kinase essential for cell viability whose activity is anomalously high in several cancers. CK2 is a validated target for cancer therapy with one small molecule inhibitor in phase I clinical trials. This enzyme is not regulated by mechanisms common to other protein kinases, and how its activity is controlled is still unclear. We present a new crystal structure of the CK2 holoenzyme that supports an autoinhibitory mechanism of regulation whereby the β-subunit plays an essential role in the formation of inactive polymeric assemblies. The derived structural model of (down)regulation by aggregation contributes to the interpretation of biochemical and functional data and paves the way for new strategies in the modulation of CK2 activity and for the design of non-ATP-competitive inhibitors targeting the interaction between the α catalytic and the β regulatory subunits.
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Affiliation(s)
- Graziano Lolli
- Department of Chemical Sciences, University of Padua, via Marzolo 1, 35131 Padova, Italy
- Venetian Institute for Molecular Medicine (VIMM), via Orus 2, 35129 Padova,
Italy
| | - Lorenzo A. Pinna
- Venetian Institute for Molecular Medicine (VIMM), via Orus 2, 35129 Padova,
Italy
- Department of Biological
Chemistry, University of Padua, viale G.
Colombo 3, 35121 Padova,
Italy
| | - Roberto Battistutta
- Department of Chemical Sciences, University of Padua, via Marzolo 1, 35131 Padova, Italy
- Venetian Institute for Molecular Medicine (VIMM), via Orus 2, 35129 Padova,
Italy
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Gyenis L, Duncan JS, Turowec JP, Bretner M, Litchfield DW. Unbiased functional proteomics strategy for protein kinase inhibitor validation and identification of bona fide protein kinase substrates: application to identification of EEF1D as a substrate for CK2. J Proteome Res 2011; 10:4887-901. [PMID: 21936567 PMCID: PMC3208357 DOI: 10.1021/pr2008994] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Protein kinases have emerged as attractive targets for treatment of several diseases prompting large-scale phosphoproteomics studies to elucidate their cellular actions and the design of novel inhibitory compounds. Current limitations include extensive reliance on consensus predictions to derive kinase-substrate relationships from phosphoproteomics data and incomplete experimental validation of inhibitors. To overcome these limitations in the case of protein kinase CK2, we employed functional proteomics and chemical genetics to enable identification of physiological CK2 substrates and validation of CK2 inhibitors including TBB and derivatives. By 2D electrophoresis and mass spectrometry, we identified the translational elongation factor EEF1D as a protein exhibiting CK2 inhibitor-dependent decreases in phosphorylation in (32)P-labeled HeLa cells. Direct phosphorylation of EEF1D by CK2 was shown by performing CK2 assays with EEF1D -FLAG from HeLa cells. Dramatic increases in EEF1D phosphorylation following λ-phosphatase treatment and phospho- EEF1D antibody recognizing EEF1D pS162 indicated phosphorylation at the CK2 site in cells. Furthermore, phosphorylation of EEF1D in the presence of TBB or TBBz is restored using CK2 inhibitor-resistant mutants. Collectively, our results demonstrate that EEF1D is a bona fide physiological CK2 substrate for CK2 phosphorylation. Furthermore, this validation strategy could be adaptable to other protein kinases and readily combined with other phosphoproteomic methods.
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Affiliation(s)
- Laszlo Gyenis
- Department of Biochemistry, The University of Western Ontario , London, Ontario, N6A 5C1, Canada
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RNA polymerase III under control: repression and de-repression. Trends Biochem Sci 2011; 36:451-6. [PMID: 21816617 DOI: 10.1016/j.tibs.2011.06.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 06/17/2011] [Accepted: 06/24/2011] [Indexed: 10/17/2022]
Abstract
The synthesis of tRNA by yeast RNA polymerase III (Pol III) is regulated in response to changing environmental conditions. This control is mediated by Maf1, the global negative regulator of Pol III transcription conserved from yeast to humans. Details regarding the molecular basis of Pol III repression by Maf1 are now emerging from recently reported structural and biochemical data on Pol III and Maf1. Efficient Pol III transcription, following the shift of cells from a non-fermentable carbon source to glucose, requires phosphorylation of Maf1. One of the newly identified Maf1 kinases is the chromatin-bound casein kinase II (CK2). Current studies have allowed us to propose an innovative mechanism of Pol III regulation. We suggest that CK2-mediated phosphorylation of Maf1, occurring directly on tDNA chromatin, controls Pol III recycling.
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Casein kinase II-mediated phosphorylation of general repressor Maf1 triggers RNA polymerase III activation. Proc Natl Acad Sci U S A 2011; 108:4926-31. [PMID: 21383183 DOI: 10.1073/pnas.1010010108] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Maf1 protein is a global negative regulator of RNA polymerase (Pol) III transcription conserved from yeast to man. We report that phosphorylation of Maf1 by casein kinase II (CK2), a highly evolutionarily conserved eukaryotic kinase, is required for efficient Pol III transcription. Both recombinant human and yeast CK2 were able to phosphorylate purified human or yeast Maf1, indicating that Maf1 can be a direct substrate of CK2. Upon transfer of Saccharomyces cerevisiae from repressive to favorable growth conditions, CK2 activity is required for the release of Maf1 from Pol III bound to a tRNA gene and for subsequent activation of tRNA transcription. In a yeast strain lacking Maf1, CK2 inhibition showed no effect on tRNA synthesis, confirming that CK2 activates Pol III via Maf1. Additionally, CK2 was found to associate with tRNA genes, and this association is enhanced in absence of Maf1, especially under repressive conditions. These results corroborate the previously reported TFIIIB-CK2 interaction and indicate an important role of CK2-mediated Maf1 phosphorylation in triggering Pol III activation.
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Łebska M, Ciesielski A, Szymona L, Godecka L, Lewandowska-Gnatowska E, Szczegielniak J, Muszyńska G. Phosphorylation of maize eukaryotic translation initiation factor 5A (eIF5A) by casein kinase 2: identification of phosphorylated residue and influence on intracellular localization of eIF5A. J Biol Chem 2010; 285:6217-26. [PMID: 20018887 PMCID: PMC2825417 DOI: 10.1074/jbc.m109.018770] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 12/15/2009] [Indexed: 11/06/2022] Open
Abstract
Maize eukaryotic translation initiation factor 5A (ZmeIF5A) co-purifies with the catalytic alpha subunit of protein kinase CK2 and is phosphorylated by this enzyme. Phosphorylated ZmeIF5A was also identified after separation of maize leaf proteins by two-dimensional electrophoresis. Multiple sequence alignment of eIF5A proteins showed that in monocots, in contrast to other eukaryotes, there are two serine/threonine residues that could potentially be phosphorylated by CK2. To identify the phosphorylation site(s) of ZmeIF5A, the serine residues potentially phosphorylated by CK2 were mutated. ZmeIF5A and its mutated variants S2A and S4A were expressed in Escherichia coli and purified. Of these recombinant proteins, only ZmeIF5A-S2A was not phosphorylated by maize CK2. Also, Arabidopsis thaliana and Saccharomyces cerevisiae eIF5A-S2A mutants were not phosphorylated despite effective phosphorylation of wild-type variants. A newly developed method exploiting the specificity of thrombin cleavage was used to confirm that Ser(2) in ZmeIF5A is indeed phosphorylated. To find a role of the Ser(2) phosphorylation, ZmeIF5A and its variants mutated at Ser(2) (S2A and S2D) were transiently expressed in maize protoplasts. The expressed fluorescence labeled proteins were visualized by confocal microscopy. Although wild-type ZmeIF5A and its S2A variant were distributed evenly between the nucleus and cytoplasm, the variant with Ser(2) replaced by aspartic acid, which mimics a phosphorylated serine, was sequestered in the nucleus. These results suggests that phosphorylation of Ser(2) plays a role in regulation of nucleocytoplasmic shuttling of eIF5A in plant cells.
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Affiliation(s)
- Maja Łebska
- From the Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Arkadiusz Ciesielski
- From the Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Lidia Szymona
- From the Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Luiza Godecka
- From the Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawińskiego 5a, 02-106 Warsaw, Poland
| | | | - Jadwiga Szczegielniak
- From the Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawińskiego 5a, 02-106 Warsaw, Poland
| | - Grażyna Muszyńska
- From the Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawińskiego 5a, 02-106 Warsaw, Poland
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Uva P, Aurisicchio L, Watters J, Loboda A, Kulkarni A, Castle J, Palombo F, Viti V, Mesiti G, Zappulli V, Marconato L, Abramo F, Ciliberto G, Lahm A, La Monica N, de Rinaldis E. Comparative expression pathway analysis of human and canine mammary tumors. BMC Genomics 2009; 10:135. [PMID: 19327144 PMCID: PMC2670324 DOI: 10.1186/1471-2164-10-135] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 03/27/2009] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Spontaneous tumors in dog have been demonstrated to share many features with their human counterparts, including relevant molecular targets, histological appearance, genetics, biological behavior and response to conventional treatments. Mammary tumors in dog therefore provide an attractive alternative to more classical mouse models, such as transgenics or xenografts, where the tumour is artificially induced. To assess the extent to which dog tumors represent clinically significant human phenotypes, we performed the first genome-wide comparative analysis of transcriptional changes occurring in mammary tumors of the two species, with particular focus on the molecular pathways involved. RESULTS We analyzed human and dog gene expression data derived from both tumor and normal mammary samples. By analyzing the expression levels of about ten thousand dog/human orthologous genes we observed a significant overlap of genes deregulated in the mammary tumor samples, as compared to their normal counterparts. Pathway analysis of gene expression data revealed a great degree of similarity in the perturbation of many cancer-related pathways, including the 'PI3K/AKT', 'KRAS', 'PTEN', 'WNT-beta catenin' and 'MAPK cascade'. Moreover, we show that the transcriptional relationships between different gene signatures observed in human breast cancer are largely maintained in the canine model, suggesting a close interspecies similarity in the network of cancer signalling circuitries. CONCLUSION Our data confirm and further strengthen the value of the canine mammary cancer model and open up new perspectives for the evaluation of novel cancer therapeutics and the development of prognostic and diagnostic biomarkers to be used in clinical studies.
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Affiliation(s)
- Paolo Uva
- IRBM P Angeletti, Merck MRL-Rome, Pomezia, Italy.
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12
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The emerging CK2 interactome: insights into the regulation and functions of CK2. Mol Cell Biochem 2008; 316:5-14. [PMID: 18553055 DOI: 10.1007/s11010-008-9830-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Accepted: 05/29/2008] [Indexed: 10/22/2022]
Abstract
Protein kinase CK2 represents a small family of protein serine/threonine kinases implicated in a variety of biological processes including events relating to cell proliferation and survival. Notably, CK2 displays oncogenic activity in mice and exhibits altered expression in several types of cancer. Accordingly, a detailed understanding of the cellular functions of CK2 and elucidation of the mechanisms by which CK2 is regulated in cells is expected to contribute to understanding its role in tumorigenesis with the prospect of novel approaches to therapy. While CK2 has traditionally been viewed as a tetrameric complex composed of two catalytic and two regulatory subunits, mounting evidence suggests that its subunits may have functions independent of tetrameric CK2 complexes. In mammals, as is the case in the budding yeast Saccharomyces cerevisiae, there are two isozymic forms of CK2, adding additional heterogeneity to the CK2 family. Studies in yeast and in human cells demonstrate that the different forms of CK2 interact with a large number of cellular proteins. To reveal new insights regarding the regulation and functions of different forms of CK2, we have examined the emerging interactomes for each of the CK2 subunits. Analysis of these interactomes for both yeast and human CK2 reinforces the view that this family of enzymes participates in a broad spectrum of cellular events. Furthermore, while there is considerable overlap between the interactomes of the individual CK2 subunits, notable differences in each of the individual interactomes provides additional evidence for functional specialization for the individual forms of CK2.
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Duncan JS, Gyenis L, Lenehan J, Bretner M, Graves LM, Haystead TA, Litchfield DW. An Unbiased Evaluation of CK2 Inhibitors by Chemoproteomics. Mol Cell Proteomics 2008; 7:1077-88. [DOI: 10.1074/mcp.m700559-mcp200] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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Singh NN, Ramji DP. Protein kinase CK2, an important regulator of the inflammatory response? J Mol Med (Berl) 2008; 86:887-97. [PMID: 18437331 DOI: 10.1007/s00109-008-0352-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 03/11/2008] [Accepted: 03/12/2008] [Indexed: 01/01/2023]
Abstract
Casein kinase 2 (CK2) is a highly conserved serine-threonine kinase that uses both adenosine triphosphate and guanosine triphosphate as phosphate donors. This constitutively active and ubiquitously expressed enzyme is often present as a tetrameric holoenzyme complex of two catalytic subunits (alpha and/or alpha') and two regulatory beta subunits. The enzyme is known to phosphorylate more than 300 substrates and controls a wide range of processes, including the regulation of cell cycle, apoptosis, transformation, and circadian rhythm. Several lines of recent evidence also suggest a potentially important role for CK2 in the control of the inflammatory response. This review will give an overview of CK2 and its regulation and describe the evidence implicating its role in inflammation.
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Affiliation(s)
- Nishi N Singh
- Cardiff School of Biosciences, Cardiff University, Cardiff, UK
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