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Mudaliar D, Mansky RH, White A, Baudhuin G, Hawkinson J, Wong H, Walters MA, Gomez-Pastor R. Discovery of a CK2α'-Biased ATP-Competitive Inhibitor from a High-Throughput Screen of an Allosteric-Inhibitor-Like Compound Library. ACS Chem Neurosci 2024; 15:2703-2718. [PMID: 38908003 DOI: 10.1021/acschemneuro.4c00062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/24/2024] Open
Abstract
Protein kinase CK2 is a holoenzyme composed of two regulatory subunits (CK2β) and two catalytic subunits (CK2α and CK2α'). CK2 controls several cellular processes, including proliferation, inflammation, and cell death. However, CK2α and CK2α' possess different expression patterns and substrates and therefore impact each of these processes differently. Elevated CK2α participates in the development of cancer, while increased CK2α' has been associated with neurodegeneration, especially Huntington's disease (HD). HD is a fatal disease for which no effective therapies are available. Genetic deletion of CK2α' in HD mouse models has ameliorated neurodegeneration. Therefore, pharmacological inhibition of CK2α' presents a promising therapeutic strategy for treating HD. However, current CK2 inhibitors are unable to discriminate between CK2α and CK2α' due to their high structural homology, especially in the targeted ATP-binding site. Using computational analyses, we found a potential type IV ("D" pocket) allosteric site that contained different residues between CK2α and CK2α' and was distal from the ATP-binding pocket featured in both kinases. We decided to look for allosteric modulators that might interact in a biased fashion with the type IV pocket on both CK2α and CK2α'. We screened a commercial library containing ∼29,000 allosteric-kinase-inhibitor-like compounds using a CK2α' activity-dependent ADP-Glo Kinase assay. Obtained hits were counter-screened against CK2α using the ADP-Glo Kinase assay, revealing two CK2α'-biased compounds. These two compounds might serve as the basis for further medicinal chemistry optimization for the potential treatment of HD.
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Affiliation(s)
- Deepti Mudaliar
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Rachel H Mansky
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Angel White
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Grace Baudhuin
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | | | - Henry Wong
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Michael A Walters
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Rocio Gomez-Pastor
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, Minnesota 55414, United States
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Mudaliar D, Mansky RH, White A, Baudhuin G, Hawkinson J, Wong H, Walters MA, Gomez-Pastor R. Identification of CK2α' selective inhibitors by the screening of an allosteric-kinase-inhibitor-like compound library. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.18.576328. [PMID: 38328231 PMCID: PMC10849513 DOI: 10.1101/2024.01.18.576328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Protein Kinase CK2 is a holoenzyme composed of two regulatory subunits (CK2β) and two catalytic subunits (CK2α and CK2α'). CK2 controls several cellular processes including proliferation, inflammation, and cell death. However, CK2α and CK2α' possess different expression patterns and substrates and therefore impact each of these processes differently. Elevated CK2α participates in the development of cancer, while increased CK2α' has been associated with neurodegeneration, especially Huntington's disease (HD). HD is a fatal disease for which no effective therapies are available. Genetic deletion of CK2α' in HD mouse models has ameliorated neurodegeneration. Therefore, pharmacological inhibition of CK2α' presents a promising therapeutic strategy for treating HD. However, current CK2 inhibitors are unable to discriminate between CK2α and CK2α' due to their high structural homology, especially in the targeted ATP binding site. Using computational analyses, we found a potential Type IV ("D" pocket) allosteric site on CK2α' that contained different residues than CK2α and was distal from the ATP binding pocket featured in both kinases. With this potential allosteric site in mind, we screened a commercial library containing ~29,000 allosteric-kinase-inhibitor-like compounds using a CK2α' activity-dependent ADP-Glo™ Kinase assay. Obtained hits were counter-screened against CK2α revealing two CK2α' selective compounds. These two compounds might serve as the basis for further medicinal chemistry optimization for the potential treatment of HD.
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Affiliation(s)
- Deepti Mudaliar
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Rachel H Mansky
- Department of Neuroscience, University of Minnesota, School of Medicine, Minneapolis, Minnesota 55414, United States
| | - Angel White
- Department of Neuroscience, University of Minnesota, School of Medicine, Minneapolis, Minnesota 55414, United States
| | - Grace Baudhuin
- Department of Neuroscience, University of Minnesota, School of Medicine, Minneapolis, Minnesota 55414, United States
| | - Jon Hawkinson
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Henry Wong
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Michael A Walters
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Rocio Gomez-Pastor
- Department of Neuroscience, University of Minnesota, School of Medicine, Minneapolis, Minnesota 55414, United States
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Kim H, Gomez-Pastor R. HSF1 and Its Role in Huntington's Disease Pathology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1410:35-95. [PMID: 36396925 DOI: 10.1007/5584_2022_742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE OF REVIEW Heat shock factor 1 (HSF1) is the master transcriptional regulator of the heat shock response (HSR) in mammalian cells and is a critical element in maintaining protein homeostasis. HSF1 functions at the center of many physiological processes like embryogenesis, metabolism, immune response, aging, cancer, and neurodegeneration. However, the mechanisms that allow HSF1 to control these different biological and pathophysiological processes are not fully understood. This review focuses on Huntington's disease (HD), a neurodegenerative disease characterized by severe protein aggregation of the huntingtin (HTT) protein. The aggregation of HTT, in turn, leads to a halt in the function of HSF1. Understanding the pathways that regulate HSF1 in different contexts like HD may hold the key to understanding the pathomechanisms underlying other proteinopathies. We provide the most current information on HSF1 structure, function, and regulation, emphasizing HD, and discussing its potential as a biological target for therapy. DATA SOURCES We performed PubMed search to find established and recent reports in HSF1, heat shock proteins (Hsp), HD, Hsp inhibitors, HSF1 activators, and HSF1 in aging, inflammation, cancer, brain development, mitochondria, synaptic plasticity, polyglutamine (polyQ) diseases, and HD. STUDY SELECTIONS Research and review articles that described the mechanisms of action of HSF1 were selected based on terms used in PubMed search. RESULTS HSF1 plays a crucial role in the progression of HD and other protein-misfolding related neurodegenerative diseases. Different animal models of HD, as well as postmortem brains of patients with HD, reveal a connection between the levels of HSF1 and HSF1 dysfunction to mutant HTT (mHTT)-induced toxicity and protein aggregation, dysregulation of the ubiquitin-proteasome system (UPS), oxidative stress, mitochondrial dysfunction, and disruption of the structural and functional integrity of synaptic connections, which eventually leads to neuronal loss. These features are shared with other neurodegenerative diseases (NDs). Currently, several inhibitors against negative regulators of HSF1, as well as HSF1 activators, are developed and hold promise to prevent neurodegeneration in HD and other NDs. CONCLUSION Understanding the role of HSF1 during protein aggregation and neurodegeneration in HD may help to develop therapeutic strategies that could be effective across different NDs.
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Affiliation(s)
- Hyuck Kim
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Rocio Gomez-Pastor
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN, USA.
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White A, McGlone A, Gomez-Pastor R. Protein Kinase CK2 and Its Potential Role as a Therapeutic Target in Huntington's Disease. Biomedicines 2022; 10:1979. [PMID: 36009526 PMCID: PMC9406209 DOI: 10.3390/biomedicines10081979] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/10/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
Huntington's Disease (HD) is a devastating neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the HTT gene, for which no disease modifying therapies are currently available. Much of the recent research has focused on developing therapies to directly lower HTT expression, and while promising, these therapies have presented several challenges regarding administration and efficacy. Another promising therapeutic approach is the modulation of HTT post-translational modifications (PTMs) that are dysregulated in disease and have shown to play a key role in HTT toxicity. Among all PTMs, modulation of HTT phosphorylation has been proposed as an attractive therapeutic option due to the possibility of orally administering specific kinase effectors. One of the kinases described to participate in HTT phosphorylation is Protein Kinase CK2. CK2 has recently emerged as a target for the treatment of several neurological and psychiatric disorders, although its role in HD remains controversial. While pharmacological studies in vitro inhibiting CK2 resulted in reduced HTT phosphorylation and increased toxicity, genetic approaches in mouse models of HD have provided beneficial effects. In this review we discuss potential therapeutic approaches related to the manipulation of HTT-PTMs with special emphasis on the role of CK2 as a therapeutic target in HD.
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Affiliation(s)
| | | | - Rocio Gomez-Pastor
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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Yu D, Zarate N, White A, Coates D, Tsai W, Nanclares C, Cuccu F, Yue JS, Brown TG, Mansky RH, Jiang K, Kim H, Nichols-Meade T, Larson SN, Gundry K, Zhang Y, Tomas-Zapico C, Lucas JJ, Benneyworth M, Öz G, Cvetanovic M, Araque A, Gomez-Pastor R. CK2 alpha prime and alpha-synuclein pathogenic functional interaction mediates synaptic dysregulation in huntington's disease. Acta Neuropathol Commun 2022; 10:83. [PMID: 35659303 PMCID: PMC9164558 DOI: 10.1186/s40478-022-01379-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 05/05/2022] [Indexed: 12/26/2022] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the HTT gene for which no therapies are available. HTT mutation causes protein misfolding and aggregation, preferentially affecting medium spiny neurons (MSNs) of the basal ganglia. Transcriptional perturbations in synaptic genes and neuroinflammation are key processes that precede MSN dysfunction and motor symptom onset. Understanding the interplay between these processes is crucial to develop effective therapeutic strategies to treat HD. We investigated the role of protein kinase CK2α', a kinase upregulated in MSNs in HD and previously associated with Parkinson's disease (PD), in the regulation of neuroinflammation and synaptic function in HD. We used the heterozygous knock-in zQ175 HD mouse model and compared that to zQ175 mice lacking one allele of CK2α' (zQ175:CK2α'(±)). CK2α' haploinsufficiency in zQ175 mice resulted in decreased levels of pro-inflammatory cytokines, HTT aggregation, astrogliosis and transcriptional alterations of synaptic genes related to glutamatergic signaling. zQ175:CK2α'(±) mice also presented increased frequency of striatal miniature excitatory postsynaptic currents (mEPSCs), an indicator of synaptic activity, and improved motor coordination compared to zQ175 mice. Neuropathological and phenotypic changes mediated by CK2α' were connected to alpha-synuclein (α-syn) dysregulation and correlated with differences in α-syn serine 129 phosphorylation (pS129-α-syn), a post-translational modification involved in α-synucleinopathy and shown to be regulated by CK2 in PD. pS129-α-syn was increased in the nuclei of MSNs in zQ175 mice and in the striatum of patients with HD, and it decreased in zQ175:CK2α'(±) mice. Collectively, our data established a novel connection between CK2α', neuroinflammation and synaptic gene dysregulation with synucleinopathy in HD and suggested common molecular mechanisms of neurodegeneration between HD and PD. Our results also support CK2α' inhibition as a potential therapeutic strategy to modulate neuronal function and neuroprotection in HD.
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Affiliation(s)
- Dahyun Yu
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Nicole Zarate
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Angel White
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - De’jah Coates
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Wei Tsai
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Carmen Nanclares
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Francesco Cuccu
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
- Department of Life and Environment Sciences, University of Cagliari, Cagliari, Italy
| | - Johnny S. Yue
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
- Mounds View High School, Arden Hills, MN USA
| | - Taylor G. Brown
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Rachel H. Mansky
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Kevin Jiang
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Hyuck Kim
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
- Present Address: HK, MEPSGEN, Seoul, 05836 South Korea
- Present Address: CTZ Department of Functional Biology, Physiology, University of Oviedo, 33006 Asturias, Spain
- Present Address: Health Research Institute of the Principality of Asturias (ISPA), 33011 Asturias, Spain
| | - Tessa Nichols-Meade
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Sarah N. Larson
- Center for Magnetic Resonance Research. Department of Radiology, School of Medicine, University of Minnesota, Minneapolis, MN USA
| | - Katherine Gundry
- Center for Magnetic Resonance Research. Department of Radiology, School of Medicine, University of Minnesota, Minneapolis, MN USA
| | - Ying Zhang
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN USA
| | - Cristina Tomas-Zapico
- Centro de Biología Molecular ‘Severo Ochoa’ (CBMSO) CSIC/UAM, Madrid, Spain
- Present Address: HK, MEPSGEN, Seoul, 05836 South Korea
- Present Address: CTZ Department of Functional Biology, Physiology, University of Oviedo, 33006 Asturias, Spain
- Present Address: Health Research Institute of the Principality of Asturias (ISPA), 33011 Asturias, Spain
| | - Jose J. Lucas
- Centro de Biología Molecular ‘Severo Ochoa’ (CBMSO) CSIC/UAM, Madrid, Spain
- Networking Research Center On Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
| | - Michael Benneyworth
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Gülin Öz
- Center for Magnetic Resonance Research. Department of Radiology, School of Medicine, University of Minnesota, Minneapolis, MN USA
| | - Marija Cvetanovic
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Alfonso Araque
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
| | - Rocio Gomez-Pastor
- Department of Neuroscience, School of Medicine, University of Minnesota, 321 Church St. SE, Jackson Hall Room 6-145, Minneapolis, MN USA
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Sano K, Iwasaki Y, Yamashita Y, Irie K, Hosokawa M, Satoh K, Mishima K. Tyrosine 136 phosphorylation of α-synuclein aggregates in the Lewy body dementia brain: involvement of serine 129 phosphorylation by casein kinase 2. Acta Neuropathol Commun 2021; 9:182. [PMID: 34772466 PMCID: PMC8590312 DOI: 10.1186/s40478-021-01281-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 10/22/2021] [Indexed: 11/10/2022] Open
Abstract
Serine 129 (S129) phosphorylation of α-synuclein (αSyn) is a central feature of Lewy body (LB) disease pathology. Although the neighboring tyrosine residues Y125, Y133, and Y136 are also phosphorylation sites, little is known regarding potential roles of phosphorylation cross-talk between these sites and its involvement in the pathogenesis of LB disease. Here, we found that αSyn aggregates are predominantly phosphorylated at Y136 in the Lewy body dementia brain, which is mediated by unexpected kinase activity of Casein kinase 2 (CK2). Aggregate formation with S129 and Y136 phosphorylation of recombinant αSyn (r-αSyn) were induced by CK2 but abolished by replacement of S129 with alanine (S129A) in vitro. Mutation of Y136 to alanine (Y136A) promoted aggregate formation and S129 phosphorylation of r-αSyn by CK2 in vitro. Introduction of Y136A r-αSyn oligomers into cultured cells exhibited increased levels of aggregates with S129 phosphorylation compared to wild-type r-αSyn oligomers. In addition, aggregate formation with S129 phosphorylation induced by introduction of wild-type r-αSyn oligomers was significantly attenuated by CK2 inhibition, which resulted in an unexpected increase in Y136 phosphorylation in cultured cells. Our findings suggest the involvement of CK2-related αSyn Y136 phosphorylation in the pathogenesis of LB disease and its potential as a therapeutic target.
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Affiliation(s)
- Kazunori Sano
- Department of Physiology and Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180 Japan
| | - Yasushi Iwasaki
- Department of Neuropathology, Institute for Medical Science of Aging, Aichi Medical University, Aichi, 480-1195 Japan
| | - Yuta Yamashita
- Department of Physiology and Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180 Japan
| | - Keiichi Irie
- Department of Physiology and Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180 Japan
| | - Masato Hosokawa
- Department of Immunological and Molecular Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, 814-0180 Japan
| | - Katsuya Satoh
- Department of Health Sciences, Unit of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523 Japan
| | - Kenichi Mishima
- Department of Physiology and Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180 Japan
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Svanbergsson A, Ek F, Martinsson I, Rodo J, Liu D, Brandi E, Haikal C, Torres-Garcia L, Li W, Gouras G, Olsson R, Björklund T, Li JY. FRET-Based Screening Identifies p38 MAPK and PKC Inhibition as Targets for Prevention of Seeded α-Synuclein Aggregation. Neurotherapeutics 2021; 18:1692-1709. [PMID: 34258749 PMCID: PMC8609038 DOI: 10.1007/s13311-021-01070-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2021] [Indexed: 02/04/2023] Open
Abstract
Aggregation of α-synuclein is associated with neurodegeneration and a hallmark pathology in synucleinopathies. These aggregates are thought to function as prion-like particles where the conformation of misfolded α-synuclein determines the traits of the induced pathology, similar to prion diseases. Still, little is known about the molecular targets facilitating the conformation-specific biological effects, but their identification could form the basis for new therapeutic interventions. High-throughput screening of annotated compound libraries could facilitate mechanistic investigation by identifying targets with impact on α-synuclein aggregation. To this end, we developed a FRET-based cellular reporter in HEK293T cells, with sensitivity down to 6.5 nM α-synuclein seeds. Using this model system, we identified GF109203X, SB202190, and SB203580 as inhibitors capable of preventing induction of α-synuclein aggregation via inhibition of p38 MAPK and PKC, respectively. We further investigated the mechanisms underlying the protective effects and found alterations in the endo-lysosomal system to be likely candidates of the protection. We found the changes did not stem from a reduction in uptake but rather alteration of lysosomal abundance and degradative capacity. Our findings highlight the value high-throughput screening brings to the mechanistic investigation of α-synuclein aggregation while simultaneously identifying novel therapeutic compounds.
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Affiliation(s)
- Alexander Svanbergsson
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden
| | - Fredrik Ek
- Chemical Biology & Therapeutics, Department of Experimental Medicinal Science, Lund University, Lund, Sweden
| | - Isak Martinsson
- Experimental Dementia Research, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Jordi Rodo
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden
| | - Di Liu
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden
| | - Edoardo Brandi
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden
| | - Caroline Haikal
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden
| | - Laura Torres-Garcia
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden
- Experimental Dementia Research, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Wen Li
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden
| | - Gunnar Gouras
- Experimental Dementia Research, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Roger Olsson
- Chemical Biology & Therapeutics, Department of Experimental Medicinal Science, Lund University, Lund, Sweden
| | - Tomas Björklund
- Molecular Neuromodulation, Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Jia-Yi Li
- Department of Experimental Medicine, Neural Plasticity and Repair, Lund University, Lund, Sweden.
- Institute of Health Sciences, China Medical University, Shenyang, 110112, China.
- Lund University, Lund, Sweden.
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Liu J, Wang X, Ma R, Li T, Guo G, Ning B, Moran TH, Smith WW. AMPK signaling mediates synphilin-1-induced hyperphagia and obesity in Drosophila. J Cell Sci 2021; 134:jcs247742. [PMID: 33443093 PMCID: PMC7875497 DOI: 10.1242/jcs.247742] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 12/15/2020] [Indexed: 12/31/2022] Open
Abstract
Expression of synphilin-1 in neurons induces hyperphagia and obesity in a Drosophila model. However, the molecular pathways underlying synphilin-1-linked obesity remain unclear. Here, Drosophila models and genetic tools were used to study the synphilin-1-linked pathways in energy balance by combining molecular biology and pharmacological approaches. We found that expression of human synphilin-1 in flies increased AMP-activated kinase (AMPK) phosphorylation at Thr172 compared with that in non-transgenic flies. Knockdown of AMPK reduced AMPK phosphorylation and food intake in non-transgenic flies, and further suppressed synphilin-1-induced AMPK phosphorylation, hyperphagia, fat storage and body weight gain in transgenic flies. Expression of constitutively activated AMPK significantly increased food intake and body weight gain in non-transgenic flies, but it did not alter food intake in the synphilin-1 transgenic flies. In contrast, expression of dominant-negative AMPK reduced food intake in both non-transgenic and synphilin-1 transgenic flies. Treatment with STO-609 also suppressed synphilin-1-induced AMPK phosphorylation, hyperphagia and body weight gain. These results demonstrate that the AMPK signaling pathway plays a critical role in synphilin-1-induced hyperphagia and obesity. These findings provide new insights into the mechanisms of synphilin-1-controlled energy homeostasis.
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Affiliation(s)
- Jingnan Liu
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA
| | - Xiaobo Wang
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Rui Ma
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA
| | - Tianxia Li
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA
| | - Gongbo Guo
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Bo Ning
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Timothy H Moran
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Wanli W Smith
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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9
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Reverse engineering Lewy bodies: how far have we come and how far can we go? Nat Rev Neurosci 2021; 22:111-131. [PMID: 33432241 DOI: 10.1038/s41583-020-00416-6] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2020] [Indexed: 12/19/2022]
Abstract
Lewy bodies (LBs) are α-synuclein (α-syn)-rich intracellular inclusions that are an important pathological hallmark of Parkinson disease and several other neurodegenerative diseases. Increasing evidence suggests that the aggregation of α-syn has a central role in LB formation and is one of the key processes that drive neurodegeneration and pathology progression in Parkinson disease. However, little is known about the mechanisms underlying the formation of LBs, their biochemical composition and ultrastructural properties, how they evolve and spread with disease progression, and their role in neurodegeneration. In this Review, we discuss current knowledge of α-syn pathology, including the biochemical, structural and morphological features of LBs observed in different brain regions. We also review the most used cellular and animal models of α-syn aggregation and pathology spreading in relation to the extent to which they reproduce key features of authentic LBs. Finally, we provide important insights into molecular and cellular determinants of LB formation and spreading, and highlight the critical need for more detailed and systematic characterization of α-syn pathology, at both the biochemical and structural levels. This would advance our understanding of Parkinson disease and other neurodegenerative diseases and allow the development of more-reliable disease models and novel effective therapeutic strategies.
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10
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Synphilin-1 Interacts with AMPK and Increases AMPK Phosphorylation. Int J Mol Sci 2020; 21:ijms21124352. [PMID: 32570982 PMCID: PMC7352261 DOI: 10.3390/ijms21124352] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 01/16/2023] Open
Abstract
A role for the cytoplasmic protein synphilin-1 in regulating energy balance has been demonstrated recently. Expression of synphilin-1 increases ATP levels in cultured cells. However, the mechanism by which synphilin-1 alters cellular energy status is unknown. Here, we used cell models and biochemical approaches to investigate the cellular functions of synphilin-1 on the AMP-activated protein kinase (AMPK) signaling pathway, which may affect energy balance. Overexpression of synphilin-1 increased AMPK phosphorylation (activation). Moreover, synphilin-1 interacted with AMPK by co-immunoprecipitation and GST (glutathione S-transferase) pull-down assays. Knockdown of synphilin-1 reduced AMPK phosphorylation. Overexpression of synphilin-1 also altered AMPK downstream signaling, i.e., a decrease in acetyl CoA carboxylase (ACC) phosphorylation, and an increase in p70S6K phosphorylation. Treatment of compound C (an AMPK inhibitor) reduced synphilin-1 binding with AMPK. In addition, compound C diminished synphilin-1-induced AMPK phosphorylation, and the increase in cellular ATP (adenosine triphosphate) levels. Our results demonstrated that synphilin-1 couples with AMPK, and they exert mutual effects on each other to regulate cellular energy status. These findings not only identify novel cellular actions of synphilin-1, but also provide new insights into the roles of synphilin-1 in regulating energy currency, ATP.
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S-Nitrosylation of G protein-coupled receptor kinase 6 and Casein kinase 2 alpha modulates their kinase activity toward alpha-synuclein phosphorylation in an animal model of Parkinson's disease. PLoS One 2020; 15:e0232019. [PMID: 32343709 PMCID: PMC7188290 DOI: 10.1371/journal.pone.0232019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 04/06/2020] [Indexed: 01/02/2023] Open
Abstract
Parkinson’s disease (PD) is a common neurodegenerative disorder which is mostly sporadic but familial-linked PD (FPD) cases have also been found. The first reported gene mutation that linked to PD is α-synuclein (α-syn). Studies have shown that mutations, increased expression or abnormal processing of α-syn can contribute to PD, but it is believed that multiple mechanisms are involved. One of the contributing factors is post-translational modification (PTM), such as phosphorylation of α-syn at serine 129 by G-protein-coupled receptor kinases (GRKs) and casein kinase 2α (CK2α). Another known important contributing factor to PD pathogenesis is oxidative and nitrosative stress. In this study, we found that GRK6 and CK2α can be S-nitrosylated by nitric oxide (NO) both in vitro and in vivo. S-nitrosylation of GRK6 and CK2α enhanced their kinase activity towards the phosphorylation of α-syn at S129. In an A53T α-syn transgenic mouse model of PD, we found that increased GRK6 and CK2α S-nitrosylation were observed in an age dependent manner and it was associated with an increased level of pSer129 α-syn. Treatment of A53T α-syn transgenic mice with Nω-Nitro-L-arginine (L-NNA) significantly reduced the S-nitrosylation of GRK6 and CK2α in the brain. Finally, deletion of neuronal nitric oxide synthase (nNOS) in A53T α-syn transgenic mice reduced the levels of pSer129 α-syn and α-syn in an age dependent manner. Our results provide a novel mechanism of how NO through S-nitrosylation of GRK6 and CK2α can enhance the phosphorylation of pSer129 α-syn in an animal model of PD.
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Renani PG, Taheri F, Rostami D, Farahani N, Abdolkarimi H, Abdollahi E, Taghizadeh E, Gheibi Hayat SM. Involvement of aberrant regulation of epigenetic mechanisms in the pathogenesis of Parkinson's disease and epigenetic-based therapies. J Cell Physiol 2019; 234:19307-19319. [PMID: 30968426 DOI: 10.1002/jcp.28622] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 03/07/2019] [Accepted: 03/14/2019] [Indexed: 12/26/2022]
Abstract
Parkinson's disease (PD) is known as a progressive neurodegenerative disorder associated with the reduction of dopamine-secreting neurons and the formation of Lewy bodies in the substantia nigra and basal ganglia routes. Aging, as well as environmental and genetic factors, are considered as disease risk factors that can make PD as a complex one. Epigenetics means studying heritable changes in gene expression or function, without altering the underlying DNA sequence. Multiple studies have shown the association of epigenetic variations with onset or progression of various types of diseases. DNA methylation, posttranslational modifications of histones and presence of microRNA (miRNA) are among epigenetic processes involved in regulating pathways related to the development of PD. Unlike genetic mutations, most epigenetic variations may be reversible or preventable. Therefore, the return of aberrant epigenetic events in different cells is a growing therapeutic approach to treatment or prevention. Currently, there are several methods for treating PD patients, the most important of which are drug therapies. However, detection of genes and epigenetic mechanisms involved in the disease can develop appropriate diagnosis and treatment of the disease before the onset of disabilities and resulting complications. The main purpose of this study was to review the most important epigenetic molecular mechanisms, epigenetic variations in PD, and epigenetic-based therapies.
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Affiliation(s)
- Pedram G Renani
- Genetic Department, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Forogh Taheri
- Genetic Department, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Daryoush Rostami
- Department of School Allied, Zabol University of Medical Sciences, Zabol, Iran
| | - Najmeh Farahani
- Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hamed Abdolkarimi
- Department of Biology, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran
| | - Elahe Abdollahi
- Department of Medical Genetics, Faculty of Medicine, Tarbiat Modares University, Tehran, Iran
| | - Eskandar Taghizadeh
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.,Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Seyed Mohammad Gheibi Hayat
- Department of Medical Genetics, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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CK2 regulates 5-HT4 receptor signaling and modulates depressive-like behavior. Mol Psychiatry 2018; 23:872-882. [PMID: 29158580 DOI: 10.1038/mp.2017.240] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 07/30/2017] [Accepted: 08/03/2017] [Indexed: 12/16/2022]
Abstract
The serotonergic neurotransmitter system has been widely implicated in the pathophysiology of mood-related disorders such as anxiety and major depressive disorder (MDD). The onset of therapeutic efficacy of traditional antidepressants is delayed by several weeks. The 5-HT4 receptor has emerged as a new therapeutic target since agonists of this receptor induce rapid antidepressant-like responses in rodents. Here we show that the 5-HT4 receptor is regulated by CK2, at transcriptional and post-transcriptional levels. We present evidence, in two different CK2α knockout mouse lines, that this regulation is region-specific, with the 5-HT4 receptor upregulated in prefrontal cortex (PFC) but not striatum or hippocampus where CK2α is also ablated. 5-HT4 receptor signaling is enhanced in vitro, as evidenced by enhanced cAMP production or receptor plasma membrane localization in the presence of CK2 inhibitor or shRNA targeting CK2α. In vivo, 5-HT4 receptor signaling is also upregulated since ERK activation is elevated and sensitive to the inverse agonist, GR113808 in the PFC of CK2α KO mice. Behaviorally, KO mice as well as mice with AAV-mediated deletion of CK2α in the PFC show a robust 'anti-depressed-like' phenotype and display an enhanced response to antidepressant treatment when tested in paradigms for mood and anxiety. Importantly, it is sufficient to overexpress the 5-HT4 receptor in the mPFC to generate mice with a similar 'anti-depressed-like' phenotype. Our findings identify the mPFC as the region that mediates the effect of enhanced 5-HT4 receptor activity and CK2 as modulator of 5-HT4 receptor levels in this brain region that regulates mood-related phenotypes.
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CK2 Oppositely Modulates l-DOPA-Induced Dyskinesia via Striatal Projection Neurons Expressing D1 or D2 Receptors. J Neurosci 2017; 37:11930-11946. [PMID: 29097596 DOI: 10.1523/jneurosci.0443-17.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 07/14/2017] [Accepted: 07/19/2017] [Indexed: 01/23/2023] Open
Abstract
We have previously shown that casein kinase 2 (CK2) negatively regulates dopamine D1 and adenosine A2A receptor signaling in the striatum. Ablation of CK2 in D1 receptor-positive striatal neurons caused enhanced locomotion and exploration at baseline, whereas CK2 ablation in D2 receptor-positive neurons caused increased locomotion after treatment with A2A antagonist, caffeine. Because both, D1 and A2A receptors, play major roles in the cellular responses to l-DOPA in the striatum, these findings prompted us to examine the impact of CK2 ablation on the effects of l-DOPA treatment in the unilateral 6-OHDA lesioned mouse model of Parkinson's disease. We report here that knock-out of CK2 in striatonigral neurons reduces the severity of l-DOPA-induced dyskinesia (LID), a finding that correlates with lowered pERK but unchanged pPKA substrate levels in D1 medium spiny neurons as well as in cholinergic interneurons. In contrast, lack of CK2 in striatopallidal neurons enhances LID and ERK phosphorylation. Coadministration of caffeine with a low dose of l-DOPA reduces dyskinesia in animals with striatopallidal knock-out to wild-type levels, suggesting a dependence on adenosine receptor activity. We also detect reduced Golf levels in the striatonigral but not in the striatopallidal knock-out in response to l-DOPA treatment.Our work shows, in a rodent model of PD, that treatment-induced dyskinesia and striatal ERK activation are bidirectionally modulated by ablating CK2 in D1- or D2-positive projection neurons, in male and female mice. The results reveal that CK2 regulates signaling events critical to LID in each of the two main populations of striatal neurons.SIGNIFICANCE STATEMENT To date, l-DOPA is the most effective treatment for PD. Over time, however, its efficacy decreases, and side effects including l-DOPA-induced dyskinesia (LID) increase, affecting up to 78% of patients within 10 years of therapy (Hauser et al., 2007). It is understood that supersensitivity of the striatonigral pathway underlies LID, however, D2 agonists were also shown to induce LID (Bezard et al., 2001; Delfino et al., 2004). Our work implicates a novel player in the expression of LID, the kinase CK2: knock-out of CK2 in striatonigral and striatopallidal neurons has opposing effects on LID. The bidirectional modulation of dyskinesia reveals a central role for CK2 in striatal physiology and indicates that both pathways contribute to LID.
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Gomez-Pastor R, Burchfiel ET, Thiele DJ. Regulation of heat shock transcription factors and their roles in physiology and disease. Nat Rev Mol Cell Biol 2017; 19:4-19. [PMID: 28852220 DOI: 10.1038/nrm.2017.73] [Citation(s) in RCA: 459] [Impact Index Per Article: 65.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The heat shock transcription factors (HSFs) were discovered over 30 years ago as direct transcriptional activators of genes regulated by thermal stress, encoding heat shock proteins. The accepted paradigm posited that HSFs exclusively activate the expression of protein chaperones in response to conditions that cause protein misfolding by recognizing a simple promoter binding site referred to as a heat shock element. However, we now realize that the mammalian family of HSFs comprises proteins that independently or in concert drive combinatorial gene regulation events that activate or repress transcription in different contexts. Advances in our understanding of HSF structure, post-translational modifications and the breadth of HSF-regulated target genes have revealed exciting new mechanisms that modulate HSFs and shed new light on their roles in physiology and pathology. For example, the ability of HSF1 to protect cells from proteotoxicity and cell death is impaired in neurodegenerative diseases but can be exploited by cancer cells to support their growth, survival and metastasis. These new insights into HSF structure, function and regulation should facilitate the development tof new disease therapeutics to manipulate this transcription factor family.
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Affiliation(s)
- Rocio Gomez-Pastor
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine
| | | | - Dennis J Thiele
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine.,Department of Biochemistry, Duke University School of Medicine.,Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina 27710, USA
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16
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Duce JA, Wong BX, Durham H, Devedjian JC, Smith DP, Devos D. Post translational changes to α-synuclein control iron and dopamine trafficking; a concept for neuron vulnerability in Parkinson's disease. Mol Neurodegener 2017; 12:45. [PMID: 28592304 PMCID: PMC5463308 DOI: 10.1186/s13024-017-0186-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 06/02/2017] [Indexed: 12/21/2022] Open
Abstract
Parkinson's disease is a multifactorial neurodegenerative disorder, the aetiology of which remains elusive. The primary clinical feature of progressively impaired motor control is caused by a loss of midbrain substantia nigra dopamine neurons that have a high α-synuclein (α-syn) and iron content. α-Syn is a neuronal protein that is highly modified post-translationally and central to the Lewy body neuropathology of the disease. This review provides an overview of findings on the role post translational modifications to α-syn have in membrane binding and intracellular vesicle trafficking. Furthermore, we propose a concept in which acetylation and phosphorylation of α-syn modulate endocytic import of iron and vesicle transport of dopamine during normal physiology. Disregulated phosphorylation and oxidation of α-syn mediate iron and dopamine dependent oxidative stress through impaired cellular location and increase propensity for α-syn aggregation. The proposition highlights a connection between α-syn, iron and dopamine, three pathological components associated with disease progression in sporadic Parkinson's disease.
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Affiliation(s)
- James A Duce
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, UK. .,Oxidation Biology Unit, the Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Parkville, VIC, Australia.
| | - Bruce X Wong
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, UK.,Oxidation Biology Unit, the Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Parkville, VIC, Australia
| | - Hannah Durham
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, UK
| | | | - David P Smith
- Biomolecular Research Centre, Sheffield Hallam University, Howard Street, Sheffield, UK
| | - David Devos
- Department of Medical Pharmacology, Lille University, INSERM U1171, CHU of Lille, Lille, France
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The Development of CK2 Inhibitors: From Traditional Pharmacology to in Silico Rational Drug Design. Pharmaceuticals (Basel) 2017; 10:ph10010026. [PMID: 28230762 PMCID: PMC5374430 DOI: 10.3390/ph10010026] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/14/2017] [Indexed: 12/20/2022] Open
Abstract
Casein kinase II (CK2) is an ubiquitous and pleiotropic serine/threonine protein kinase able to phosphorylate hundreds of substrates. Being implicated in several human diseases, from neurodegeneration to cancer, the biological roles of CK2 have been intensively studied. Upregulation of CK2 has been shown to be critical to tumor progression, making this kinase an attractive target for cancer therapy. Several CK2 inhibitors have been developed so far, the first being discovered by "trial and error testing". In the last decade, the development of in silico rational drug design has prompted the discovery, de novo design and optimization of several CK2 inhibitors, active in the low nanomolar range. The screening of big chemical libraries and the optimization of hit compounds by Structure Based Drug Design (SBDD) provide telling examples of a fruitful application of rational drug design to the development of CK2 inhibitors. Ligand Based Drug Design (LBDD) models have been also applied to CK2 drug discovery, however they were mainly focused on methodology improvements rather than being critical for de novo design and optimization. This manuscript provides detailed description of in silico methodologies whose applications to the design and development of CK2 inhibitors proved successful and promising.
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18
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CK2-An Emerging Target for Neurological and Psychiatric Disorders. Pharmaceuticals (Basel) 2017; 10:ph10010007. [PMID: 28067771 PMCID: PMC5374411 DOI: 10.3390/ph10010007] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 12/20/2016] [Accepted: 12/30/2016] [Indexed: 12/16/2022] Open
Abstract
Protein kinase CK2 has received a surge of attention in recent years due to the evidence of its overexpression in a variety of solid tumors and multiple myelomas as well as its participation in cell survival pathways. CK2 is also upregulated in the most prevalent and aggressive cancer of brain tissue, glioblastoma multiforme, and in preclinical models, pharmacological inhibition of the kinase has proven successful in reducing tumor size and animal mortality. CK2 is highly expressed in the mammalian brain and has many bona fide substrates that are crucial in neuronal or glial homeostasis and signaling processes across synapses. Full and conditional CK2 knockout mice have further elucidated the importance of CK2 in brain development, neuronal activity, and behavior. This review will discuss recent advances in the field that point to CK2 as a regulator of neuronal functions and as a potential novel target to treat neurological and psychiatric disorders.
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19
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Silica-coated magnetic nanoparticles impair proteasome activity and increase the formation of cytoplasmic inclusion bodies in vitro. Sci Rep 2016; 6:29095. [PMID: 27378605 PMCID: PMC4932509 DOI: 10.1038/srep29095] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 06/15/2016] [Indexed: 12/28/2022] Open
Abstract
The potential toxicity of nanoparticles, particularly to neurons, is a major concern. In this study, we assessed the cytotoxicity of silica-coated magnetic nanoparticles containing rhodamine B isothiocyanate dye (MNPs@SiO2(RITC)) in HEK293 cells, SH-SY5Y cells, and rat primary cortical and dopaminergic neurons. In cells treated with 1.0 μg/μl MNPs@SiO2(RITC), the expression of several genes related to the proteasome pathway was altered, and proteasome activity was significantly reduced, compared with control and with 0.1 μg/μl MNPs@SiO2(RITC)-treated cells. Due to the reduction of proteasome activity, formation of cytoplasmic inclusions increased significantly in HEK293 cells over-expressing the α–synuclein interacting protein synphilin-1 as well as in primary cortical and dopaminergic neurons. Primary neurons, particularly dopaminergic neurons, were more vulnerable to MNPs@SiO2(RITC) than SH-SY5Y cells. Cellular polyamines, which are associated with protein aggregation, were significantly altered in SH-SY5Y cells treated with MNPs@SiO2(RITC). These findings highlight the mechanisms of neurotoxicity incurred by nanoparticles.
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Ganapathy K, Datta I, Sowmithra S, Joshi P, Bhonde R. Influence of 6-Hydroxydopamine Toxicity on α-Synuclein Phosphorylation, Resting Vesicle Expression, and Vesicular Dopamine Release. J Cell Biochem 2016; 117:2719-2736. [DOI: 10.1002/jcb.25570] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 04/07/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Kavina Ganapathy
- School of Regenerative Medicine; Manipal University; Bengaluru Karnataka India
| | - Indrani Datta
- Department of Biophysics; National Institute of Mental Health and Neurosciences, an Institute of National Importance; Bengaluru Karnataka India
| | - Sowmithra Sowmithra
- Department of Biophysics; National Institute of Mental Health and Neurosciences, an Institute of National Importance; Bengaluru Karnataka India
| | - Preeti Joshi
- Department of Biophysics; National Institute of Mental Health and Neurosciences, an Institute of National Importance; Bengaluru Karnataka India
| | - Ramesh Bhonde
- School of Regenerative Medicine; Manipal University; Bengaluru Karnataka India
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Samuel F, Flavin WP, Iqbal S, Pacelli C, Sri Renganathan SD, Trudeau LE, Campbell EM, Fraser PE, Tandon A. Effects of Serine 129 Phosphorylation on α-Synuclein Aggregation, Membrane Association, and Internalization. J Biol Chem 2015; 291:4374-85. [PMID: 26719332 DOI: 10.1074/jbc.m115.705095] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Indexed: 02/04/2023] Open
Abstract
Although trace levels of phosphorylated α-synuclein (α-syn) are detectable in normal brains, nearly all α-syn accumulated within Lewy bodies in Parkinson disease brains is phosphorylated on serine 129 (Ser-129). The role of the phosphoserine residue and its effects on α-syn structure, function, and intracellular accumulation are poorly understood. Here, co-expression of α-syn and polo-like kinase 2 (PLK2), a kinase that targets Ser-129, was used to generate phosphorylated α-syn for biophysical and biological characterization. Misfolding and fibril formation of phosphorylated α-syn isoforms were detected earlier, although the fibrils remained phosphatase- and protease-sensitive. Membrane binding of α-syn monomers was differentially affected by phosphorylation depending on the Parkinson disease-linked mutation. WT α-syn binding to presynaptic membranes was not affected by phosphorylation, whereas A30P α-syn binding was greatly increased, and A53T α-syn was slightly lower, implicating distal effects of the carboxyl- on amino-terminal membrane binding. Endocytic vesicle-mediated internalization of pre-formed fibrils into non-neuronal cells and dopaminergic neurons matched the efficacy of α-syn membrane binding. Finally, the disruption of internalized vesicle membranes was enhanced by the phosphorylated α-syn isoforms, a potential means for misfolded extracellular or lumenal α-syn to access cytosolic α-syn. Our results suggest that the threshold for vesicle permeabilization is evident even at low levels of α-syn internalization and are relevant to therapeutic strategies to reduce intercellular propagation of α-syn misfolding.
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Affiliation(s)
- Filsy Samuel
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada
| | | | - Sobia Iqbal
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada
| | - Consiglia Pacelli
- the Departments of Pharmacology and Neurosciences, Central Nervous System Research Group (GRSNC), Faculty of Medicine, Université de Montréal, Québec H4T 1J4, Canada, and
| | | | - Louis-Eric Trudeau
- the Departments of Pharmacology and Neurosciences, Central Nervous System Research Group (GRSNC), Faculty of Medicine, Université de Montréal, Québec H4T 1J4, Canada, and
| | - Edward M Campbell
- the Integrative Cell Biology Program, Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois 60153
| | - Paul E Fraser
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada, the Departments of Medical Biophysics and
| | - Anurag Tandon
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada, Medicine, University of Toronto, Toronto, Ontario M5T 2S8, Canada
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Larsen K, Madsen LB, Farajzadeh L, Bendixen C. Splicing variants of porcine synphilin-1. Meta Gene 2015; 5:32-42. [PMID: 26101749 PMCID: PMC4468357 DOI: 10.1016/j.mgene.2015.04.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 04/29/2015] [Accepted: 04/30/2015] [Indexed: 11/24/2022] Open
Abstract
Parkinson's disease (PD), idiopathic and familial, is characterized by degradation of dopaminergic neurons and the presence of Lewy bodies (LB) in the substantia nigra. LBs contain aggregated proteins of which α-synuclein is the major component. The protein synphilin-1 interacts and colocalizes with α-synuclein in LBs. The aim of this study was to isolate and characterize porcine synphilin-1 and isoforms hereof with the future perspective to use the pig as a model for Parkinson's disease. The porcine SNCAIP cDNA was cloned by reverse transcriptase PCR. The spatial expression of SNCAIP mRNA was investigated by RNAseq. The presented work reports the molecular cloning and characterization of the porcine (Sus scrofa) synphilin-1 cDNA (SNCAIP) and three splice variants hereof. The porcine SNCAIP cDNA codes for a protein (synphilin-1) of 919 amino acids which shows a high similarity to human (90%) and to mouse (84%) synphilin-1. Three shorter transcript variants of the synphilin-1 gene were identified, all lacking one or more exons. SNCAIP transcripts were detected in most examined organs and tissues and the highest expression was found in brain tissues and lung. Conserved splicing variants and a novel splice form of synhilin-1 were found in this study. All synphilin-1 isoforms encoded by the identified transcript variants lack functional domains important for protein degradation. The full-length porcine SNCAIP cDNA encoding synphilin-1 was cloned and characterized. Three splicing variants of synphilin-1 were identified. Both conserved and novel splicing variant were found. SNCAIP mRNA was differently expressed in analyzed tissues and organs with highest expression in brain tissue and lung.
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Affiliation(s)
- Knud Larsen
- Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, P.O. Box 50, DK-8830 Tjele, Denmark
| | - Lone Bruhn Madsen
- Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, P.O. Box 50, DK-8830 Tjele, Denmark
| | - Leila Farajzadeh
- Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, P.O. Box 50, DK-8830 Tjele, Denmark
| | - Christian Bendixen
- Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, P.O. Box 50, DK-8830 Tjele, Denmark
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Wang Y, Schachner M. The intracellular domain of L1CAM binds to casein kinase 2α and is neuroprotective via inhibition of the tumor suppressors PTEN and p53. J Neurochem 2015; 133:828-43. [PMID: 25727698 DOI: 10.1111/jnc.13083] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/05/2015] [Accepted: 02/24/2015] [Indexed: 02/05/2023]
Abstract
Cell adhesion molecule L1 promotes neuritogenesis and neuronal survival through triggering MAPK pathways. Based on the findings that L1 is associated with casein kinase 2 (CK2), and that deficiency in PTEN promotes neuritogenesis in vitro and regeneration after trauma, we examined the functional relationship between L1 and PTEN. In parallel, we investigated the tumor suppressor p53, which also regulates neuritogenesis. Here, we report that the intracellular domain of L1 binds to the subunit CK2α, and that knockdown of L1 leads to CK2 dephosphorylation and an increase in PTEN and p53 levels. Overexpression of L1, but not the L1 mutants L1 (S1181N, E1184V), which reduced binding between L1 and CK2, reduced expression levels of PTEN and p53 proteins, and enhanced levels of phosphorylated CK2α and mammalian target of rapamycin, which is a downstream effector of PTEN and p53. Treatment of neurons with a CK2 inhibitor or transfection with CK2α siRNA increased levels of PTEN and p53, and inhibited neuritogenesis. The combined observations indicate that L1 downregulates expression of PTEN and p53 via direct binding to CK2α. We suggest that L1 stimulates neuritogenesis by activating CK2α leading to decreased levels of PTEN and p53 via a novel, L1-triggered and CK2α-mediated signal transduction pathway. L1CAM (L1 cell adhesion molecule) is implicated in neural functions through the cognate src/MAP kinase signaling pathway. We now describe a novel signaling platform operating via the alpha subunit of casein kinase 2 which binds to the intracellular domain of L1. Knockdown of L1CAM leads to increased levels of tumor suppressor PTEN (phosphatase and tensin homolog) and p53, known to inhibit neuritogenesis in vitro and recovery from trauma in vivo. By activating this enzyme, L1CAM adds to its beneficial functions by decreasing the levels of PTEN and p53.
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Affiliation(s)
- Yan Wang
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong, China
| | - Melitta Schachner
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong, China
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Moussaud S, Malany S, Mehta A, Vasile S, Smith LH, McLean PJ. Targeting α-synuclein oligomers by protein-fragment complementation for drug discovery in synucleinopathies. Expert Opin Ther Targets 2015; 19:589-603. [PMID: 25785645 DOI: 10.1517/14728222.2015.1009448] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Reducing the burden of α-synuclein oligomeric species represents a promising approach for disease-modifying therapies against synucleinopathies such as Parkinson's disease and dementia with Lewy bodies. However, the lack of efficient drug discovery strategies that specifically target α-synuclein oligomers has been a limitation to drug discovery programs. RESEARCH DESIGN AND METHODS Here we describe an innovative strategy that harnesses the power of bimolecular protein-fragment complementation to monitor synuclein-synuclein interactions. We have developed two robust models to monitor α-synuclein oligomerization by generating novel stable cell lines expressing α-synuclein fusion proteins for either fluorescent or bioluminescent protein-fragment complementation under the tetracycline-controlled transcriptional activation system. MAIN OUTCOME MEASURES A pilot screen was performed resulting in the identification of two potential hits, a p38 MAPK inhibitor and a casein kinase 2 inhibitor, thereby demonstrating the suitability of our protein-fragment complementation assay for the measurement of α-synuclein oligomerization in living cells at high throughput. CONCLUSIONS The application of the strategy described herein to monitor α-synuclein oligomer formation in living cells with high throughput will facilitate drug discovery efforts for disease-modifying therapies against synucleinopathies and other proteinopathies.
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Affiliation(s)
- Simon Moussaud
- Mayo Clinic Florida, Neuroscience , 4500 San Pablo road, Jacksonville, 32224, FL , USA
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Li T, Liu J, Smith WW. Synphilin-1 binds ATP and regulates intracellular energy status. PLoS One 2014; 9:e115233. [PMID: 25545246 PMCID: PMC4278857 DOI: 10.1371/journal.pone.0115233] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 11/19/2014] [Indexed: 11/19/2022] Open
Abstract
Recent studies have suggested that synphilin-1, a cytoplasmic protein, is involved in energy homeostasis. Overexpression of synphilin-1 in neurons results in hyperphagia and obesity in animal models. However, the mechanism by which synphilin-1 alters energy homeostasis is unknown. Here, we used cell models and biochemical approaches to investigate the cellular functions of synphilin-1 that may affect energy balance. Synphilin-1 was pulled down by ATP-agarose beads, and the addition of ATP and ADP reduced this binding, indicating that synphilin-1 bound ADP and ATP. Synphilin-1 also bound GMP, GDP, and GTP but with a lower affinity than it bound ATP. In contrast, synphilin-1 did not bind with CTP. Overexpression of synphilin-1 in HEK293T cells significantly increased cellular ATP levels. Genetic alteration to abolish predicted ATP binding motifs of synphilin-1 or knockdown of synphilin-1 by siRNA reduced cellular ATP levels. Together, these data demonstrate that synphilin-1 binds and regulates the cellular energy molecule, ATP. These findings provide a molecular basis for understanding the actions of synphilin-1 in energy homeostasis.
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Affiliation(s)
- Tianxia Li
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States of America
| | - Jingnan Liu
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States of America
| | - Wanli W. Smith
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States of America
- * E-mail:
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Lussier MP, Gu X, Lu W, Roche KW. Casein kinase 2 phosphorylates GluA1 and regulates its surface expression. Eur J Neurosci 2014; 39:1148-58. [PMID: 24712994 DOI: 10.1111/ejn.12494] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/17/2013] [Accepted: 01/02/2014] [Indexed: 11/30/2022]
Abstract
Controlling the density of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) at synapses is essential for regulating the strength of excitatory neurotransmission. In particular, the phosphorylation of AMPARs is important for defining both synaptic expression and intracellular routing of receptors. Phosphorylation is a post-translational modification known to regulate many cellular events and the C-termini of glutamate receptors are important targets. Recently, the first intracellular loop1 region of the GluA1 subunit of AMPARs was reported to regulate synaptic targeting through phosphorylation of S567 by Ca2+ /calmodulin-dependent protein kinase II (CaMKII). Intriguingly, the loop1 region of all four AMPAR subunits contains many putative phosphorylation sites (S/T/Y), leaving the possibility that other kinases may regulate AMPAR surface expression via phosphorylation of the loop regions. To explore this hypothesis, we used in vitro phosphorylation assays with a small panel of purified kinases and found that casein kinase 2 (CK2) phosphorylates the GluA1 and GluA2 loop1 regions, but not GluA3 or GluA4. Interestingly, when we reduced the endogenous expression of CK2 using a specific short hairpin RNA against the regulatory subunit CK2β, we detected a reduction of GluA1 surface expression, whereas GluA2 was unchanged. Furthermore, we identified S579 of GluA1 as a substrate of CK2, and the expression of GluA1 phosphodeficient mutants in hippocampal neurons displayed reduced surface expression. Therefore, our study identifies CK2 as a regulator of GluA1 surface expression by phosphorylating the intracellular loop1 region.
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Affiliation(s)
- Marc P Lussier
- Receptor Biology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
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Swirski M, Miners JS, de Silva R, Lashley T, Ling H, Holton J, Revesz T, Love S. Evaluating the relationship between amyloid-β and α-synuclein phosphorylated at Ser129 in dementia with Lewy bodies and Parkinson's disease. ALZHEIMERS RESEARCH & THERAPY 2014; 6:77. [PMID: 25452767 PMCID: PMC4248436 DOI: 10.1186/s13195-014-0077-y] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 10/14/2014] [Indexed: 01/12/2023]
Abstract
Introduction Lewy body and Alzheimer-type pathologies often co-exist.
Several studies suggest a synergistic relationship between amyloid-β (Aβ)
and α-synuclein (α-syn) accumulation. We have explored the relationship
between Aβ accumulation and the phosphorylation of α-syn at serine-129
(pSer129 α-syn), in post-mortem human brain tissue and in SH-SY5Y
neuroblastoma cells transfected to overexpress human α-syn. Methods We measured levels of Aβ40, Aβ42, α-syn and pSer129 α-syn by
sandwich enzyme-linked immunosorbent assay, in soluble and insoluble
fractions of midfrontal, cingulate and parahippocampal cortex and
thalamus, from cases of Parkinson’s disease (PD) with (PDD; n = 12) and
without dementia (PDND; n = 23), dementia with Lewy bodies (DLB; n = 10)
and age-matched controls (n = 17). We also examined the relationship of
these measurements to cognitive decline, as measured by time-to-dementia
and the mini-mental state examination (MMSE) score in the PD patients,
and to Braak tangle stage. Results In most brain regions, the concentration of insoluble
pSer129 α-syn correlated positively, and soluble pSer129 α-syn
negatively, with the levels of soluble and insoluble Aβ. Insoluble
pSer129 α-syn also correlated positively with Braak stage. In most
regions, the levels of insoluble and soluble Aβ and the proportion of
insoluble α-syn that was phosphorylated at Ser129 were significantly
higher in the PD and DLB groups than the controls, and higher in the PDD
and DLB groups than the PDND brains. In PD, the MMSE score correlated
negatively with the level of insoluble pSer129 α-syn. Exposure of SH-SY5Y
cells to aggregated Aβ42 significantly increased the proportion of α-syn
that was phosphorylated at Ser129 (aggregated Aβ40 exposure had a
smaller, non-significant effect). Conclusions Together, these data show that the concentration of pSer129
α-syn in brain tissue homogenates is directly related to the level of Aβ
and Braak tangle stage, and predicts cognitive status in Lewy body
diseases. Electronic supplementary material The online version of this article (doi:10.1186/s13195-014-0077-y) contains supplementary material, which is available to
authorized users.
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Affiliation(s)
- Marta Swirski
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Bristol, UK
| | - J Scott Miners
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Rohan de Silva
- Department of Molecular Neuroscience, Reta Lila Weston Institute of Neurological Studies and Queen Square Brain Bank for Neurological Disorders, Institute of Neurology, University College London, London, UK
| | - Tammaryn Lashley
- Department of Molecular Neuroscience, Reta Lila Weston Institute of Neurological Studies and Queen Square Brain Bank for Neurological Disorders, Institute of Neurology, University College London, London, UK
| | - Helen Ling
- Department of Molecular Neuroscience, Reta Lila Weston Institute of Neurological Studies and Queen Square Brain Bank for Neurological Disorders, Institute of Neurology, University College London, London, UK
| | - Janice Holton
- Department of Molecular Neuroscience, Reta Lila Weston Institute of Neurological Studies and Queen Square Brain Bank for Neurological Disorders, Institute of Neurology, University College London, London, UK
| | - Tamas Revesz
- Department of Molecular Neuroscience, Reta Lila Weston Institute of Neurological Studies and Queen Square Brain Bank for Neurological Disorders, Institute of Neurology, University College London, London, UK
| | - Seth Love
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Bristol, UK
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Synphilin-1A is a phosphoprotein phosphatase 1-interacting protein and affects PPP1 sorting to subcellular compartments. J Mol Neurosci 2014; 55:385-95. [PMID: 24902662 DOI: 10.1007/s12031-014-0343-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 05/27/2014] [Indexed: 12/24/2022]
Abstract
Lewy bodies (LBs) are synphilin-1 (Sph1)-containing aggregates and histological hallmarks of Parkinson's disease. Therefore, understanding processes which modulate the aggregation of Sph1, or its isoform Sph1A, will contribute to our understanding of LBs formation. Protein phosphorylation promotes aggregation, but protein phosphatases with activity towards Sph1 have not been described. The present study documents the identification of a novel Sph1A/phosphoprotein phosphatase 1 (PPP1) complex and unravels its regulatory effect on Sph1A aggregation. Using yeast co-transformation and overlay blot assay, the interaction between Sph1A and PPP1 was mapped to the Sph1A RVTF motif. Then, Sph1A overexpression in human embryonic kidney 293 cells demonstrated that Sph1A specifically targets endogenous PPP1 isoforms to inclusion bodies and that Sph1A/PPP1 complex disruption enhances inclusion bodies formation. Finally, as Sph1A interacted with PPP1CC2, a PPP1 sperm-specific isoform, Sph1 and Sph1A expression was addressed in male germ cells by qRT-PCR, revealing high expression levels in round spermatids. Together, these observations established Sph1A as a novel PPP1-interacting protein able to affect PPP1 sorting to subcellular compartments and Sph1A/PPP1 complex as a negative modulator of LBs formation. Contrarily, in physiological conditions, Sph1 isoforms are pointed as putative participants in vesicle dynamics with implications in neurotransmission and spermiogenesis.
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Tenreiro S, Eckermann K, Outeiro TF. Protein phosphorylation in neurodegeneration: friend or foe? Front Mol Neurosci 2014; 7:42. [PMID: 24860424 PMCID: PMC4026737 DOI: 10.3389/fnmol.2014.00042] [Citation(s) in RCA: 171] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 04/22/2014] [Indexed: 12/15/2022] Open
Abstract
Protein misfolding and aggregation is a common hallmark in neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), and fronto-temporal dementia (FTD). In these disorders, the misfolding and aggregation of specific proteins occurs alongside neuronal degeneration in somewhat specific brain areas, depending on the disorder and the stage of the disease. However, we still do not fully understand the mechanisms governing protein aggregation, and whether this constitutes a protective or detrimental process. In PD, alpha-synuclein (aSyn) forms protein aggregates, known as Lewy bodies, and is phosphorylated at serine 129. Other residues have also been shown to be phosphorylated, but the significance of phosphorylation in the biology and pathophysiology of the protein is still controversial. In AD and in FTD, hyperphosphorylation of tau protein causes its misfolding and aggregation. Again, our understanding of the precise consequences of tau phosphorylation in the biology and pathophysiology of the protein is still limited. Through the use of a variety of model organisms and technical approaches, we are now gaining stronger insight into the effects of phosphorylation in the behavior of these proteins. In this review, we cover recent findings in the field and discuss how targeting phosphorylation events might be used for therapeutic intervention in these devastating diseases of the nervous system.
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Affiliation(s)
- Sandra Tenreiro
- Cell and Molecular Neuroscience Unit, Instituto de Medicina Molecular Lisboa, Portugal
| | - Katrin Eckermann
- Department of Neurology, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen Göttingen, Germany
| | - Tiago F Outeiro
- Cell and Molecular Neuroscience Unit, Instituto de Medicina Molecular Lisboa, Portugal ; Instituto de Fisiologia, Faculdade de Medicina da Universidade de Lisboa Lisboa, Portugal ; Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen Göttingen, Germany
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Rebholz H, Zhou M, Nairn AC, Greengard P, Flajolet M. Selective knockout of the casein kinase 2 in d1 medium spiny neurons controls dopaminergic function. Biol Psychiatry 2013; 74:113-21. [PMID: 23290496 PMCID: PMC3878430 DOI: 10.1016/j.biopsych.2012.11.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 11/14/2012] [Accepted: 11/15/2012] [Indexed: 12/17/2022]
Abstract
BACKGROUND Dopamine, crucial for the regulation of motor function and reward, acts through receptors mainly expressed in striatum as well as cortex. Dysregulation of dopaminergic signaling is associated with various neuropsychiatric disorders. Consequently, dopamine-regulating drugs are effectively used in treating these disorders, such as L-DOPA for Parkinson's disease, methylphenidate for attention-deficit/hyperactivity disorder, or antipsychotics for schizophrenia. As a result, there has been much interest in dissecting signaling networks in the two morphologically indistinguishable D1- and D2-receptor-expressing medium spiny neurons. Our previous results highlighted a role for casein kinase 2 (CK2) in the modulation of dopamine D1 receptor (D1R) signaling in cells. METHODS To study the importance of CK2 in vivo, we have selectively knocked out CK2, in either D1- or D2-medium spiny neurons (MSNs) and characterized the mice behaviorally and biochemically (n = 4-18). RESULTS The D1-MSN knockout mice exhibited distinct behavioral phenotypes including novelty-induced hyperlocomotion and exploratory behavior, defective motor control, and motor learning. All of these behavioral traits are indicative of dysregulated dopamine signaling and the underlying mechanism appears to be an alteration of D1R signaling. In support of this hypothesis, D1R levels were upregulated in the knockout mice, as well as phosphorylation of DARPP-32 (dopamine- and cyclic adenosine monophosphate [cAMP]-regulated phospho-protein of 32 kDa), most of the behavioral phenotypes were abolished by the D1R antagonist, SCH23390, and the D2-MSN knockout mice displayed no obvious behavioral phenotype. CONCLUSIONS A single kinase, CK2, in D1-MSNs significantly alters dopamine signaling, a finding that could have therapeutic implications for disorders characterized by dopamine imbalance such as Parkinson's disease, attention-deficit/hyperactivity disorder, and schizophrenia.
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Affiliation(s)
- Heike Rebholz
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
| | - Mingming Zhou
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
| | - Angus C. Nairn
- Department of Psychiatry, Yale University School of Medicine, Ribicoff Research Facilities, CMHC, New Haven, CT 06508, US
| | - Paul Greengard
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
| | - Marc Flajolet
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, 10065, USA
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The casein kinase 2-nrf1 axis controls the clearance of ubiquitinated proteins by regulating proteasome gene expression. Mol Cell Biol 2013; 33:3461-72. [PMID: 23816881 DOI: 10.1128/mcb.01271-12] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Impairment of the ubiquitin-proteasome system (UPS) has been implicated in the pathogenesis of human diseases, including neurodegenerative disorders. Thus, stimulating proteasome activity is a promising strategy to ameliorate these age-related diseases. Here we show that the protein kinase casein kinase 2 (CK2) regulates the transcriptional activity of Nrf1 to control the expression of the proteasome genes and thus the clearance of ubiquitinated proteins. We identify CK2 as an Nrf1-binding protein and find that the knockdown of CK2 enhances the Nrf1-dependent expression of the proteasome subunit genes. Real-time monitoring of proteasome activity reveals that CK2 knockdown alleviates the accumulation of ubiquitinated proteins upon proteasome inhibition. Furthermore, we identify Ser 497 of Nrf1 as the CK2 phosphorylation site and demonstrate that its alanine substitution (S497A) augments the transcriptional activity of Nrf1 and mitigates proteasome dysfunction and the formation of p62-positive juxtanuclear inclusion bodies upon proteasome inhibition. These results indicate that the CK2-mediated phosphorylation of Nrf1 suppresses the proteasome gene expression and activity and thus suggest that the CK2-Nrf1 axis is a potential therapeutic target for diseases associated with UPS impairment.
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Basso E, Antas P, Marijanovic Z, Gonçalves S, Tenreiro S, Outeiro TF. PLK2 modulates α-synuclein aggregation in yeast and mammalian cells. Mol Neurobiol 2013; 48:854-62. [PMID: 23677647 DOI: 10.1007/s12035-013-8473-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 05/06/2013] [Indexed: 11/24/2022]
Abstract
Phosphorylation of α-synuclein (aSyn) on serine 129 is one of the major post-translation modifications found in Lewy bodies, the typical pathological hallmark of Parkinson's disease. Here, we found that both PLK2 and PLK3 phosphorylate aSyn on serine 129 in yeast. However, only PLK2 increased aSyn cytotoxicity and the percentage of cells presenting cytoplasmic foci. Consistently, in mammalian cells, PLK2 induced aSyn phosphorylation on serine 129 and induced an increase in the size of the inclusions. Our study supports a role for PLK2 in the generation of aSyn inclusions by a mechanism that does not depend directly on serine 129 phosphorylation.
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Affiliation(s)
- Elisa Basso
- Cell and Molecular Neuroscience Unit, Instituto de Medicina Molecular, Lisbon, Portugal
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Abstract
AIMS The pathogenesis of obesity remains incompletely understood. Drosophila have conserved neuroendocrine and digestion systems with human and become an excellent system for studying energy homeostasis. Here, we reported a novel obesity Drosophila model, in which expression of human protein, synphilin-1 (SP1), in neurons fosters positive energy balance. SUBJECTS AND METHODS To further understand the actions of SP1 in energy balance control, the upstream activation sequence UAS/GAL4 system was used to generate human SP1 transgenic Drosophila. We characterized a human SP1 transgenic Drosophila by assessing SP1 expression, fat lipid deposition, food intake and fly locomotor activity to determine the major behavioral changes and their consequences in the development of the obesity-like phenotype. RESULTS Overexpression of SP1 in neurons, but not peripheral cells, increased the body weight of flies compared with that of non-transgenic controls. SP1 increased food intake but did not affect locomotor activity. SP1 increased the levels of triacylglycerol, and the size of fat body cells and lipid droplets, indicating that SP1 increased lipid-fat disposition. Survival studies showed that SP1 transgenic flies were more resistant to food deprivation. SP1 regulated lipin gene expression that may participate in SP1-induced fat deposition and starvation resistance. CONCLUSION These studies demonstrate that SP1 expression affects energy homeostasis in ways that enhance positive energy balance and provide a useful obesity model for future pathogenesis and therapeutic studies.
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Bellucci A, Zaltieri M, Navarria L, Grigoletto J, Missale C, Spano P. From α-synuclein to synaptic dysfunctions: new insights into the pathophysiology of Parkinson's disease. Brain Res 2012; 1476:183-202. [PMID: 22560500 DOI: 10.1016/j.brainres.2012.04.014] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 03/30/2012] [Accepted: 04/09/2012] [Indexed: 10/28/2022]
Abstract
Alpha-synuclein is a natively unfolded protein playing a key role in the regulation of several neuronal synaptic functions in physiological and pathological conditions. Many studies, over the past years, have shown that it is actively involved in PD pathophysiology. Alpha-synuclein is integrated in a complex network of neuronal processes through the interaction with cytosolic and synaptic proteins. Hence, it is not the sole α-synuclein pathology but its effects on diverse protein partners and specific cellular pathways in the membrane and/or cytosolic districts such as endoplasmic reticulum/Golgi, axonal and synaptic compartments of dopaminergic neurons, that may cause the onset of neuronal cell dysfunction and degeneration which are among the key pathological features of the PD brain. Here we summarize a series of experimental data supporting that α-synuclein aggregation may induce dysfunction and degeneration of synapses via these multiple mechanisms. Taken together, these data add new insights into the complex mechanisms underlying synaptic derangement in PD and other α-synucleinopathies. This article is part of a Special Issue entitled: Brain Integration.
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Affiliation(s)
- Arianna Bellucci
- Division of Pharmacology, Department of Biomedical Sciences and Biotechnologies and National Institute of Neuroscience, University of Brescia, Brescia, Italy.
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Aggresome formation and segregation of inclusions influence toxicity of α-synuclein and synphilin-1 in yeast. Biochem Soc Trans 2012; 39:1476-81. [PMID: 21936837 DOI: 10.1042/bst0391476] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PD (Parkinson's disease) is a neurodegenerative disorder, caused by a selective loss of dopaminergic neurons in the substantia nigra, which affects an increasing number of the elderly population worldwide. One of the major hallmarks of PD is the occurrence of intracellular protein deposits in the dying neurons, termed Lewy bodies, which contain different proteins, including aggregated α-synuclein and its interacting protein synphilin-1. During the last decade, a number of groups developed yeast models that reproduced important features of PD and allowed the deciphering of pathways underlying the cytotoxicity triggered by α-synuclein. Here, we review the recent contributions obtained with yeast models designed to study the presumed pathobiology of synphilin-1. These models pointed towards a crucial role of the sirtuin Sir2 and the chaperonin complex TRiC (TCP-1 ring complex)/CCT (chaperonin containing TCP-1) in handling misfolded and aggregated proteins.
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Abstract
Aggregated a-synuclein is the major component of inclusions in Parkinson's disease and other synucleinopathy brains indicating that a-syn aggregation is associated with the pathogenesis of neurodegenerative disorders. Although the mechanisms underlying a-syn aggregation and toxicity are not fully elucidated, it is clear that a-syn undergoes post-translational modifications and interacts with numerous proteins and other macromolecules, metals, hormones, neurotransmitters, drugs and poisons that can all modulate its aggregation propensity. The current and most recent findings regarding the factors modulating a-syn aggregation process are discussed in detail.
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Li X, Tamashiro KLK, Liu Z, Bello NT, Wang X, Aja S, Bi S, Ladenheim EE, Ross CA, Moran TH, Smith WW. A novel obesity model: synphilin-1-induced hyperphagia and obesity in mice. Int J Obes (Lond) 2011; 36:1215-21. [PMID: 22158267 PMCID: PMC3439552 DOI: 10.1038/ijo.2011.235] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Aims The pathogenesis of obesity remains incompletely understood and the exploration of the role of novel proteins in obesity may provide important insights into its causes and treatments. Here we report a previously unidentified role for synphilin-1 in the controls of food intake and body weight. Synphilin-1, a cytoplasmic protein, was initially identified as an interaction partner of alpha-synuclein, and has implications in Parkinson's disease pathogenesis related to protein aggregation. Subjects and methods To study the in vivo role of synphilin-1, we characterized a human synphilin-1 transgenic mouse (SP1) by assessing synphilin-1 expression, plasma parameters, food intake and spontaneous activity to determine the major behavioral changes and their consequences in the development of the obesity phenotype. Results Expression of human synphilin-1 in brain neurons in SP1 mice resulted in increased food intake, body weight and body fat. SP1 mice also displayed hyperinsulinemia, hyperleptinemia and impaired glucose tolerance. Pair-feeding SP1 mice to amounts consumed by non-transgenic mice prevented the increased body weight, adiposity, hyperinsulinemia and hyperleptinemia demonstrating that these were all the consequences of increased food intake. Transgenic expression of synphilin-1 was enriched in hypothalamic nuclei involved in feeding control, and fasting induced elevated endogenous synphilin-1 levels at these sites, suggesting that synphilin-1 is an important player in the hypothalamic energy balance regulatory system. Conclusion These studies identify a novel function of synphilin-1 in controlling food intake and body weight, and may provide a unique obesity model for future studies of obesity pathogenesis and therapeutics.
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Affiliation(s)
- X Li
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA
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Bellucci A, Navarria L, Zaltieri M, Missale C, Spano P. α-Synuclein synaptic pathology and its implications in the development of novel therapeutic approaches to cure Parkinson's disease. Brain Res 2011; 1432:95-113. [PMID: 22153624 DOI: 10.1016/j.brainres.2011.11.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 11/11/2011] [Accepted: 11/11/2011] [Indexed: 12/24/2022]
Abstract
Parkinson's disease (PD) is characterized by a progressive loss of dopamine (DA) neurons of the nigrostriatal system and by the presence of Lewy bodies (LB), proteinaceous inclusions mainly composed of filamentous α-synuclein aggregates. Alpha-synuclein is a natively unfolded protein which plays a central role in the control of dopaminergic neuronal functions and which is thought to be critically implicated in PD pathophysiology. Indeed, besides the fact that α-synuclein is the main protein component of LB, genetic studies showed that mutations and multiplications of the α-synuclein gene are responsible for the onset of familial forms of PD. A large body of evidence indicates that α-synuclein pathology at dopaminergic synapses may underlie the onset of neuronal cell dysfunction and degeneration in the PD brain. Thus, since the available therapeutic approaches to cure this disease are still limited, we hypothesized that the analysis of the α-synuclein synaptic proteome/lipidome may represent a tool to identify novel potential therapeutic targets to cure this disorder. We thus performed a critical review of studies describing α-synuclein pathophysiology at synaptic sites in experimental models of PD and in this paper we outline the most relevant findings regarding the specific modulatory effects exerted by α-synuclein in the control of synaptic functions in physiological and pathological conditions. The conclusions of these studies allow to single out novel potential therapeutic targets among the α-synuclein synaptic partners. These targets may be considered for the development of new pharmacological and gene-based strategies to cure PD.
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Affiliation(s)
- Arianna Bellucci
- Division of Pharmacology, Department of Biomedical Sciences and Biotechnology and National Institute of Neuroscience - Italy, School of Medicine, University of Brescia, Brescia, Italy.
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Predominance of CK2α over CK2α′ in the mammalian brain. Mol Cell Biochem 2011; 356:169-75. [DOI: 10.1007/s11010-011-0963-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 06/24/2011] [Indexed: 10/18/2022]
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Bi W, Zhang G, Sun Y, Zhu L, Wang C, Liang Y, Shi Q, Tao E. Serine 129 Phosphorylation of α-Synuclein Cross-Links with Tissue Transglutaminase to Form Lewy Body-Like Inclusion Bodies. ISRN NEUROLOGY 2011; 2011:732879. [PMID: 22389828 PMCID: PMC3263562 DOI: 10.5402/2011/732879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 03/16/2011] [Indexed: 02/04/2023]
Abstract
Intraneuronal depositions of α-synuclein have been implicated in the pathogenesis of Parkinsons's disease (PD). Previous reports have identified the crosslinking between α-synuclein and tTG (tissue transglutaminase) in both PD patients and the cellular model. However, no researches have been conducted to further investigate their interaction in physiological conditions. To address this question, we generated the SH-SY5Y cell line which stably expressed the wild-type or mutant (Ser129Ala) α-synuclein. After the treatment with okadaic acid, α-synuclein started forming aggregates upon the activation of tTG. Coimmunoprecipitation assays revealed a decreased interaction of the mutant α-synuclein S129A with tTG compared with the wild-type α-synuclein. Cells expressing the wild-type α-synuclein showed increased eosinophilic cytoplasmic inclusion bodies that resembled Lewy bodies compared with the mutant. Double immunofluorescence staining confirmed the colocalization of the phosphorylated α-synuclein and the tTG in the cells. The S129A mutant demonstrated a lesser degree of colocalization than the wild type.
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Affiliation(s)
- Wei Bi
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
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Büttner S, Delay C, Franssens V, Bammens T, Ruli D, Zaunschirm S, de Oliveira RM, Outeiro TF, Madeo F, Buée L, Galas MC, Winderickx J. Synphilin-1 enhances α-synuclein aggregation in yeast and contributes to cellular stress and cell death in a Sir2-dependent manner. PLoS One 2010; 5:e13700. [PMID: 21060871 PMCID: PMC2965147 DOI: 10.1371/journal.pone.0013700] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Accepted: 10/07/2010] [Indexed: 11/19/2022] Open
Abstract
Background Parkinson's disease is characterized by the presence of cytoplasmic inclusions, known as Lewy bodies, containing both aggregated α-synuclein and its interaction partner, synphilin-1. While synphilin-1 is known to accelerate inclusion formation by α-synuclein in mammalian cells, its effect on cytotoxicity remains elusive. Methodology/Principal Findings We expressed wild-type synphilin-1 or its R621C mutant either alone or in combination with α-synuclein in the yeast Saccharomyces cerevisiae and monitored the intracellular localization and inclusion formation of the proteins as well as the repercussions on growth, oxidative stress and cell death. We found that wild-type and mutant synphilin-1 formed inclusions and accelerated inclusion formation by α-synuclein in yeast cells, the latter being correlated to enhanced phosphorylation of serine-129. Synphilin-1 inclusions co-localized with lipid droplets and endomembranes. Consistently, we found that wild-type and mutant synphilin-1 interacts with detergent-resistant membrane domains, known as lipid rafts. The expression of synphilin-1 did not incite a marked growth defect in exponential cultures, which is likely due to the formation of aggresomes and the retrograde transport of inclusions from the daughter cells back to the mother cells. However, when the cultures approached stationary phase and during subsequent ageing of the yeast cells, both wild-type and mutant synphilin-1 reduced survival and triggered apoptotic and necrotic cell death, albeit to a different extent. Most interestingly, synphilin-1 did not trigger cytotoxicity in ageing cells lacking the sirtuin Sir2. This indicates that the expression of synphilin-1 in wild-type cells causes the deregulation of Sir2-dependent processes, such as the maintenance of the autophagic flux in response to nutrient starvation. Conclusions/Significance Our findings demonstrate that wild-type and mutant synphilin-1 are lipid raft interacting proteins that form inclusions and accelerate inclusion formation of α-synuclein when expressed in yeast. Synphilin-1 thereby induces cytotoxicity, an effect most pronounced for the wild-type protein and mediated via Sir2-dependent processes.
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Affiliation(s)
- Sabrina Büttner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Charlotte Delay
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
- Alzheimer & Tauopathies, Inserm U837, Lille, France
- Jean-Pierre Aubert Research Centre, Université Lille Nord de France, Lille, France
- Faculté de Médecine-Pole Recherche, Université du Droit et de la Santé de Lille, Lille, France
- Centre Hospitalier Universitaire, Lille, France
| | - Vanessa Franssens
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
| | - Tine Bammens
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
| | - Doris Ruli
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Sandra Zaunschirm
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Rita Machado de Oliveira
- Cell and Molecular Neuroscience Unit, Instituto de Medicina Molecular, Lisboa, Portugal
- Instituto de Fisiologia, Universidade de Lisboa, Lisboa, Portugal
| | - Tiago Fleming Outeiro
- Cell and Molecular Neuroscience Unit, Instituto de Medicina Molecular, Lisboa, Portugal
- Instituto de Fisiologia, Universidade de Lisboa, Lisboa, Portugal
| | - Frank Madeo
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Luc Buée
- Alzheimer & Tauopathies, Inserm U837, Lille, France
- Jean-Pierre Aubert Research Centre, Université Lille Nord de France, Lille, France
- Faculté de Médecine-Pole Recherche, Université du Droit et de la Santé de Lille, Lille, France
- Centre Hospitalier Universitaire, Lille, France
| | - Marie-Christine Galas
- Alzheimer & Tauopathies, Inserm U837, Lille, France
- Jean-Pierre Aubert Research Centre, Université Lille Nord de France, Lille, France
- Faculté de Médecine-Pole Recherche, Université du Droit et de la Santé de Lille, Lille, France
- Centre Hospitalier Universitaire, Lille, France
| | - Joris Winderickx
- Functional Biology, Katholieke Universiteit Leuven, Heverlee, Belgium
- * E-mail:
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Abstract
CK2 is a pleiotropic, ubiquitous, and constitutively active protein kinase (PK), with both cytosolic and nuclear localization in most mammalian cells. The holoenzyme is generally composed of two catalytic (alpha and/or alpha') and two regulatory (beta) subunits, but the free alpha/alpha' subunits are catalytically active by themselves and can be present in cells under some circumstances. CK2 catalyzes the phosphorylation of more than 300 substrates characterized by multiple acidic residues surrounding the phosphor-acceptor amino acid, and, consequently, it plays a key role in several physiological and pathological processes. But how can one kinase orchestrate all these tasks faithfully? How is it possible that one kinase can, despite all pleiotropic characteristics of PKs in general, be involved in so many different biochemical events? Is CK2 a druggable target? Several questions are still to be clearly answered, and this review is an occasion for a fruitful discussion.
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Affiliation(s)
- Giorgio Cozza
- Molecular Modeling Section, Dipartimento di Scienze Farmaceutiche, Università di Padova, via Marzolo 5, Padova, Italy
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Perez DI, Gil C, Martinez A. Protein kinases CK1 and CK2 as new targets for neurodegenerative diseases. Med Res Rev 2010; 31:924-54. [DOI: 10.1002/med.20207] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Lou H, Montoya SE, Alerte TNM, Wang J, Wu J, Peng X, Hong CS, Friedrich EE, Mader SA, Pedersen CJ, Marcus BS, McCormack AL, Di Monte DA, Daubner SC, Perez RG. Serine 129 phosphorylation reduces the ability of alpha-synuclein to regulate tyrosine hydroxylase and protein phosphatase 2A in vitro and in vivo. J Biol Chem 2010; 285:17648-61. [PMID: 20356833 PMCID: PMC2878529 DOI: 10.1074/jbc.m110.100867] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Revised: 03/06/2010] [Indexed: 11/22/2022] Open
Abstract
Alpha-synuclein (a-Syn), a protein implicated in Parkinson disease, contributes significantly to dopamine metabolism. a-Syn binding inhibits the activity of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine synthesis. Phosphorylation of TH stimulates its activity, an effect that is reversed by protein phosphatase 2A (PP2A). In cells, a-Syn overexpression activates PP2A. Here we demonstrate that a-Syn significantly inhibited TH activity in vitro and in vivo and that phosphorylation of a-Syn serine 129 (Ser-129) modulated this effect. In MN9D cells, a-Syn overexpression reduced TH serine 19 phosphorylation (Ser(P)-19). In dopaminergic tissues from mice overexpressing human a-Syn in catecholamine neurons only, TH-Ser-19 and TH-Ser-40 phosphorylation and activity were also reduced, whereas PP2A was more active. Cerebellum, which lacks excess a-Syn, had PP2A activity identical to controls. Conversely, a-Syn knock-out mice had elevated TH-Ser-19 phosphorylation and activity and less active PP2A in dopaminergic tissues. Using an a-Syn Ser-129 dephosphorylation mimic, with serine mutated to alanine, TH was more inhibited, whereas PP2A was more active in vitro and in vivo. Phosphorylation of a-Syn Ser-129 by Polo-like-kinase 2 in vitro reduced the ability of a-Syn to inhibit TH or activate PP2A, identifying a novel regulatory role for Ser-129 on a-Syn. These findings extend our understanding of normal a-Syn biology and have implications for the dopamine dysfunction of Parkinson disease.
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Affiliation(s)
- Haiyan Lou
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
- the Department of Pharmacology, Shandong University School of Medicine, Jinan, Shandong 250012, China
| | - Susana E. Montoya
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Tshianda N. M. Alerte
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Jian Wang
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Jianjun Wu
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Xiangmin Peng
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Chang-Sook Hong
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Emily E. Friedrich
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Samantha A. Mader
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Courtney J. Pedersen
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Brian S. Marcus
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | | | | | - S. Colette Daubner
- the Department of Biological Sciences, St. Mary's University, San Antonio, Texas 78229, and
| | - Ruth G. Perez
- From the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
- the Departments of Neurology and
- Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
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Waxman EA, Giasson BI. A novel, high-efficiency cellular model of fibrillar alpha-synuclein inclusions and the examination of mutations that inhibit amyloid formation. J Neurochem 2010; 113:374-88. [PMID: 20132485 DOI: 10.1111/j.1471-4159.2010.06592.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Intracytoplasmic alpha-synuclein (alpha-syn) amyloidogenic inclusions are a major pathological feature of Parkinson's disease, dementia with Lewy body disease and multiple systems atrophy. The mechanisms involved in the formation and inhibition of these aggregates are areas of intense investigation. The present study characterizes a novel cellular model for the study of alpha-syn aggregation, incorporating nucleation-dependent aggregation and a new function for calcium phosphate precipitation. Cultured cells were readily induced to develop large, cytoplasmic alpha-syn filamentous aggregates that were hyperphosphorylated, often ubiquitinated and thioflavin positive. These cellular aggregates formed in the majority of transfected cells and recruited approximately half of endogenously expressed alpha-syn. Using this system, we examined single-point mutations that inhibit alpha-syn amyloid formation in vitro. Three mutations (V66P, T72P and T75P) significantly hindered alpha-syn aggregation in this cell model. The T75P mutant, which could abrogate amyloid formation of wild-type alpha-syn in vitro, did not prevent wild-type alpha-syn cellular aggregates. These studies suggest that the propensity of alpha-syn to form cellular aggregates may be more pronounced than in isolated in vitro studies. This novel high-efficiency cellular model of alpha-syn aggregation is a valuable system that may be used to further understand alpha-syn aggregation and allow for the generation of future therapeutics.
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Affiliation(s)
- Elisa A Waxman
- Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104-6084, USA
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Oueslati A, Fournier M, Lashuel HA. Role of post-translational modifications in modulating the structure, function and toxicity of alpha-synuclein: implications for Parkinson's disease pathogenesis and therapies. PROGRESS IN BRAIN RESEARCH 2010; 183:115-45. [PMID: 20696318 DOI: 10.1016/s0079-6123(10)83007-9] [Citation(s) in RCA: 253] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A better understanding of the molecular and cellular determinants that influence the pathology of Parkinson's disease (PD) is essential for developing effective diagnostic, preventative and therapeutic strategies to treat this devastating disease. A number of post-translational modifications to alpha-syn are present within the Lewy bodies in the brains of affected patients and transgenic models of PD and related disorders. However, whether disease-associated alpha-syn post-translational modifications promote or inhibit alpha-syn aggregation and neurotoxicity in vivo remains unknown. Herein, we summarize and discuss the major disease-associated post-translational modifications (phosphorylation, truncation and ubiquitination) and present our current understanding of the effect of these modifications on alpha-syn aggregation and toxicity. Elucidating the molecular mechanisms underlying post-translation modifications of alpha-syn and the consequences of such modifications on the biochemical, structural, aggregation and toxic properties of the protein is essential for unravelling the molecular basis of its function(s) in health and disease. Furthermore, the identification of the natural enzymes involved in regulating the post-translational modifications of alpha-synuclein will yield novel and more tractable therapeutic targets to treat PD and related synucleinopathies.
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Affiliation(s)
- Abid Oueslati
- Laboratory of Molecular Neurobiology and Neuroproteomics, Brain Mind Institute, The Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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Abstract
We present evidence, using biochemical and cellular approaches, that the kinase, CK2, negatively controls signaling via Galpha(s) (or Galpha(olf)) coupled to dopamine D1 and adenosine A2A receptors. Pharmacological inhibition of CK2 or CK2 knockdown by RNAi lead to elevated cAMP levels in dopamine D1 receptor-activated neuroblastoma cells. Phosphorylation levels of protein kinase A substrates were increased in the presence of CK2 inhibitors in mouse striatal slices. The effect of D1 receptor and A2A receptor agonists on the phosphorylation of protein kinase A sites was potentiated upon CK2 inhibition. Furthermore, in cell lines, we observed that reduction in CK2 activity, pharmacologically or genetically, reduced the amount of D1 receptor that was internalized in response to dopamine. Finally, the beta subunit of CK2 was found to interact specifically with the Galpha(s) subunit through protein interaction analyses. Thus CK2 can inhibit G protein-coupled receptor action by enabling faster receptor internalization, possibly through a direct association with Galpha(s).
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Molecular pathology of Lewy body diseases. Int J Mol Sci 2009; 10:724-45. [PMID: 19399218 PMCID: PMC2671999 DOI: 10.3390/ijms10030724] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Revised: 02/03/2009] [Accepted: 02/23/2009] [Indexed: 11/16/2022] Open
Abstract
Lewy body diseases are characterized by the presence of Lewy bodies, alpha-synuclein(AS)-positive inclusions in the brain. Since their main component is conformationally modified AS, aggregation of the latter is thought to be a key pathogenic event in these diseases. The analysis of inclusion body constituents gives additional information about pathways also involved in the pathology of synucleinopathies. Widespread mitochondrial dysfunction is very closely related to disease development. The impairment of protein degradation pathways, including both the ubiquitin-proteasome system and the autophagy-lysosome pathway also play an important role during the development of Lewy body diseases. Finally, differential expression changes of isoforms corresponding to genes primarily involved in Lewy body formation point to alternative splicing as another important mechanism in the development of Parkinson’s disease, as well as dementia with Lewy bodies. The present paper attempts to give an overview of recent molecular findings related to the pathogenesis of Lewy body diseases.
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McCormack AL, Mak SK, Shenasa M, Langston WJ, Forno LS, Di Monte DA. Pathologic modifications of alpha-synuclein in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated squirrel monkeys. J Neuropathol Exp Neurol 2008; 67:793-802. [PMID: 18648323 PMCID: PMC2745435 DOI: 10.1097/nen.0b013e318180f0bd] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
alpha-Synuclein expression is increased in dopaminergic neurons challenged by toxic insults. Here, we assessed whether this upregulation is accompanied by pathologic accumulation of alpha-synuclein and protein modifications (i.e. nitration, phosphorylation, and aggregation) that are typically observed in Parkinson disease and in other synucleinopathies. A single injection of the neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to squirrel monkeys caused a buildup of alpha-synuclein but not of beta-synuclein or synaptophysin within nigral dopaminergic cell bodies. Immunohistochemistry and immunoelectron microscopy also revealed large numbers of dystrophic axons labeled with alpha-synuclein. Antibodies that recognize nitrated and phosphorylated (at serine 129) alpha-synuclein stained neuronal cell bodies and dystrophic axons in the midbrain of MPTP-treated animals. After toxicant exposure, alpha-synuclein deposition occurred at the level of neuronal axons in which amorphous protein aggregates were observed by immunoelectron microscopy. In a subset of these axons, immunoreactivity for alpha-synuclein was still evident after tissue digestion with proteinase K, further indicating the accumulation of insoluble protein. These data indicate that toxic injury can induce alpha-synuclein modifications that have been implicated in the pathogenesis of human synucleinopathies. The findings are also consistent with a pattern of evolution of alpha-synuclein pathology that may begin with the accumulation and aggregation of the protein within damaged axons.
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Specificity and regulation of casein kinase-mediated phosphorylation of alpha-synuclein. J Neuropathol Exp Neurol 2008. [PMID: 18451726 DOI: 10.1097/nen.0b013e3186fc995] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
alpha-Synuclein (alpha-syn) is the major component of pathologic inclusions that characterize neurodegenerative disorders such as Parkinson disease, dementia with Lewy body disease, and multiple system atrophy. The present study uses novel phospho-specific antibodies to assess the presence and regulation of phosphorylated Ser87 and Ser129 in alpha-syn in human brain samples and in a transgenic mouse model of alpha-synucleinopathies. By immunohistochemistry, alpha-syn phosphorylated at Ser129, but not at Ser87, was abundant in alpha-syn inclusions. Under normal conditions, Ser129 phosphorylation, but not Ser87 phosphorylation, was detected at low levels in the soluble biochemical fractions in human alpha-syn transgenic mice and stably transfected cultured cells. Therefore, a role for Ser87 phosphorylation in alpha-synucleinopathies is unlikely, and in vitro assays showed that phosphorylation at this site would inhibit polymerization. In vitro studies also indicated that hyperphosphorylation of Ser129 alpha-syn in pathologic inclusions may be due in part to the intrinsic properties of aggregated alpha-syn to act as substrates for kinases but not phosphatases. Further studies in transgenic mice and cultured cells suggest that cellular toxicity, including proteasomal dysfunction, increases casein kinase 2 activity, which results in elevated Ser129 alpha-syn phosphorylation. These data provide novel explanations for the presence of hyperphosphorylated Ser129 alpha-syn in pathologic inclusions.
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