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Villar-Pazos S, Thomas L, Yang Y, Chen K, Lyles JB, Deitch BJ, Ochaba J, Ling K, Powers B, Gingras S, Kordasiewicz HB, Grubisha MJ, Huang YH, Thomas G. Neural deficits in a mouse model of PACS1 syndrome are corrected with PACS1- or HDAC6-targeting therapy. Nat Commun 2023; 14:6547. [PMID: 37848409 PMCID: PMC10582149 DOI: 10.1038/s41467-023-42176-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 09/29/2023] [Indexed: 10/19/2023] Open
Abstract
PACS1 syndrome is a neurodevelopmental disorder (NDD) caused by a recurrent de novo missense mutation in PACS1 (p.Arg203Trp (PACS1R203W)). The mechanism by which PACS1R203W causes PACS1 syndrome is unknown, and no curative treatment is available. Here, we use patient cells and PACS1 syndrome mice to show that PACS1 (or PACS-1) is an HDAC6 effector and that the R203W substitution increases the PACS1/HDAC6 interaction, aberrantly potentiating deacetylase activity. Consequently, PACS1R203W reduces acetylation of α-tubulin and cortactin, causing the Golgi ribbon in hippocampal neurons and patient-derived neural progenitor cells (NPCs) to fragment and overpopulate dendrites, increasing their arborization. The dendrites, however, are beset with varicosities, diminished spine density, and fewer functional synapses, characteristic of NDDs. Treatment of PACS1 syndrome mice or patient NPCs with PACS1- or HDAC6-targeting antisense oligonucleotides, or HDAC6 inhibitors, restores neuronal structure and synaptic transmission in prefrontal cortex, suggesting that targeting PACS1R203W/HDAC6 may be an effective therapy for PACS1 syndrome.
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Affiliation(s)
- Sabrina Villar-Pazos
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter Campus (VBC), Vienna, Austria
| | - Laurel Thomas
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
| | - Yunhan Yang
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
| | - Kun Chen
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jenea B Lyles
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
| | - Bradley J Deitch
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
| | | | - Karen Ling
- Ionis Pharmaceuticals, Carlsbad, CA, USA
| | | | - Sebastien Gingras
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | | | - Melanie J Grubisha
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Translational Neuroscience Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yanhua H Huang
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Translational Neuroscience Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Gary Thomas
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA.
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2
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Nicoll RA, Schulman H. Synaptic memory and CaMKII. Physiol Rev 2023; 103:2877-2925. [PMID: 37290118 PMCID: PMC10642921 DOI: 10.1152/physrev.00034.2022] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 04/26/2023] [Accepted: 04/30/2023] [Indexed: 06/10/2023] Open
Abstract
Ca2+/calmodulin-dependent protein kinase II (CaMKII) and long-term potentiation (LTP) were discovered within a decade of each other and have been inextricably intertwined ever since. However, like many marriages, it has had its up and downs. Based on the unique biochemical properties of CaMKII, it was proposed as a memory molecule before any physiological linkage was made to LTP. However, as reviewed here, the convincing linkage of CaMKII to synaptic physiology and behavior took many decades. New technologies were critical in this journey, including in vitro brain slices, mouse genetics, single-cell molecular genetics, pharmacological reagents, protein structure, and two-photon microscopy, as were new investigators attracted by the exciting challenge. This review tracks this journey and assesses the state of this marriage 40 years on. The collective literature impels us to propose a relatively simple model for synaptic memory involving the following steps that drive the process: 1) Ca2+ entry through N-methyl-d-aspartate (NMDA) receptors activates CaMKII. 2) CaMKII undergoes autophosphorylation resulting in constitutive, Ca2+-independent activity and exposure of a binding site for the NMDA receptor subunit GluN2B. 3) Active CaMKII translocates to the postsynaptic density (PSD) and binds to the cytoplasmic C-tail of GluN2B. 4) The CaMKII-GluN2B complex initiates a structural rearrangement of the PSD that may involve liquid-liquid phase separation. 5) This rearrangement involves the PSD-95 scaffolding protein, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs), and their transmembrane AMPAR-regulatory protein (TARP) auxiliary subunits, resulting in an accumulation of AMPARs in the PSD that underlies synaptic potentiation. 6) The stability of the modified PSD is maintained by the stability of the CaMKII-GluN2B complex. 7) By a process of subunit exchange or interholoenzyme phosphorylation CaMKII maintains synaptic potentiation in the face of CaMKII protein turnover. There are many other important proteins that participate in enlargement of the synaptic spine or modulation of the steps that drive and maintain the potentiation. In this review we critically discuss the data underlying each of the steps. As will become clear, some of these steps are more firmly grounded than others, and we provide suggestions as to how the evidence supporting these steps can be strengthened or, based on the new data, be replaced. Although the journey has been a long one, the prospect of having a detailed cellular and molecular understanding of learning and memory is at hand.
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Affiliation(s)
- Roger A Nicoll
- Department of Cellular and Molecular Pharmacology, University of California at San Francisco, San Francisco, California, United States
| | - Howard Schulman
- Department of Neurobiology, Stanford University School of Medicine, Stanford, California, United States
- Panorama Research Institute, Sunnyvale, California, United States
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3
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Yamada R, Takada S. Postsynaptic protein assembly in three and two dimensions studied by mesoscopic simulations. Biophys J 2023; 122:3395-3410. [PMID: 37496268 PMCID: PMC10465727 DOI: 10.1016/j.bpj.2023.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/25/2023] [Accepted: 07/21/2023] [Indexed: 07/28/2023] Open
Abstract
Recently, cellular biomolecular condensates formed via phase separation have received considerable attention. While they can be formed either in cytosol (denoted as 3D) or beneath the membrane (2D), the underlying difference between the two has not been well clarified. To compare the phase behaviors in 3D and 2D, postsynaptic density (PSD) serves as a model system. PSD is a protein condensate located under the postsynaptic membrane that influences the localization of glutamate receptors and thus contributes to synaptic plasticity. Recent in vitro studies have revealed the formation of droplets of various soluble PSD proteins via liquid-liquid phase separation. However, it is unclear how these protein condensates are formed beneath the membrane and how they specifically affect the localization of glutamate receptors in the membrane. In this study, focusing on the mixture of a glutamate receptor complex, AMPAR-TARP, and a ubiquitous scaffolding protein, PSD-95, we constructed a mesoscopic model of protein-domain interactions in PSD and performed comparative molecular simulations. The results showed a sharp contrast in the phase behaviors of protein assemblies in 3D and those under the membrane (2D). A mixture of a soluble variant of the AMPAR-TARP complex and PSD-95 in the 3D system resulted in a phase-separated condensate, which was consistent with the experimental results. However, with identical domain interactions, AMPAR-TARP embedded in the membrane formed clusters with PSD-95, but did not form a stable separated phase. Thus, the cluster formation behaviors of PSD proteins in the 3D and 2D systems were distinct. The current study suggests that, more generally, stable phase separation can be more difficult to achieve in and beneath the membrane than in 3D systems.
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Affiliation(s)
- Risa Yamada
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Shoji Takada
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan.
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Yim YY, Nestler EJ. Cell-Type-Specific Neuroproteomics of Synapses. Biomolecules 2023; 13:998. [PMID: 37371578 PMCID: PMC10296650 DOI: 10.3390/biom13060998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/08/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
In the last two decades, our knowledge of synaptic proteomes and their relationship to normal brain function and neuropsychiatric disorders has been expanding rapidly through the use of more powerful neuroproteomic approaches. However, mass spectrometry (MS)-based neuroproteomic studies of synapses still require cell-type, spatial, and temporal proteome information. With the advancement of sample preparation and MS techniques, we have just begun to identify and understand proteomes within a given cell type, subcellular compartment, and cell-type-specific synapse. Here, we review the progress and limitations of MS-based neuroproteomics of synapses in the mammalian CNS and highlight the recent applications of these approaches in studying neuropsychiatric disorders such as major depressive disorder and substance use disorders. Combining neuroproteomic findings with other omics studies can generate an in-depth, comprehensive map of synaptic proteomes and possibly identify new therapeutic targets and biomarkers for several central nervous system disorders.
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Affiliation(s)
- Yun Young Yim
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA;
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5
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Calcium/Calmodulin-Stimulated Protein Kinase II (CaMKII): Different Functional Outcomes from Activation, Depending on the Cellular Microenvironment. Cells 2023; 12:cells12030401. [PMID: 36766743 PMCID: PMC9913510 DOI: 10.3390/cells12030401] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/20/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023] Open
Abstract
Calcium/calmodulin-stimulated protein kinase II (CaMKII) is a family of broad substrate specificity serine (Ser)/threonine (Thr) protein kinases widely expressed in many tissues that is capable of mediating diverse functional responses depending on its cellular and molecular microenvironment. This review briefly summarises current knowledge on the structure and regulation of CaMKII and focuses on how the molecular environment, and interaction with binding partner proteins, can produce different populations of CaMKII in different cells, or in different subcellular locations within the same cell, and how these different populations of CaMKII can produce diverse functional responses to activation following an increase in intracellular calcium concentration. This review also explores the possibility that identifying and characterising the molecular interactions responsible for the molecular targeting of CaMKII in different cells in vivo, and identifying the sites on CaMKII and/or the binding proteins through which these interactions occur, could lead to the development of highly selective inhibitors of specific CaMKII-mediated functional responses in specific cells that would not affect CaMKII-mediated responses in other cells. This may result in the development of new pharmacological agents with therapeutic potential for many clinical conditions.
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Bai Y, Wang H, Li C. SAPAP Scaffold Proteins: From Synaptic Function to Neuropsychiatric Disorders. Cells 2022; 11:cells11233815. [PMID: 36497075 PMCID: PMC9740047 DOI: 10.3390/cells11233815] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/24/2022] [Accepted: 11/25/2022] [Indexed: 11/30/2022] Open
Abstract
Excitatory (glutamatergic) synaptic transmission underlies many aspects of brain activity and the genesis of normal human behavior. The postsynaptic scaffolding proteins SAP90/PSD-95-associated proteins (SAPAPs), which are abundant components of the postsynaptic density (PSD) at excitatory synapses, play critical roles in synaptic structure, formation, development, plasticity, and signaling. The convergence of human genetic data with recent in vitro and in vivo animal model data indicates that mutations in the genes encoding SAPAP1-4 are associated with neurological and psychiatric disorders, and that dysfunction of SAPAP scaffolding proteins may contribute to the pathogenesis of various neuropsychiatric disorders, such as schizophrenia, autism spectrum disorders, obsessive compulsive disorders, Alzheimer's disease, and bipolar disorder. Here, we review recent major genetic, epigenetic, molecular, behavioral, electrophysiological, and circuitry studies that have advanced our knowledge by clarifying the roles of SAPAP proteins at the synapses, providing new insights into the mechanistic links to neurodevelopmental and neuropsychiatric disorders.
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Affiliation(s)
- Yunxia Bai
- Key Laboratory of Brain Functional Genomics (STCSM & MOE), Affiliated Mental Health Center (ECNU), School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China
- Shanghai Changning Mental Health Center, Shanghai 200335, China
| | - Huimin Wang
- Key Laboratory of Brain Functional Genomics (STCSM & MOE), Affiliated Mental Health Center (ECNU), School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China
- Shanghai Changning Mental Health Center, Shanghai 200335, China
- NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai, Shanghai 200062, China
| | - Chunxia Li
- Key Laboratory of Brain Functional Genomics (STCSM & MOE), Affiliated Mental Health Center (ECNU), School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China
- Shanghai Changning Mental Health Center, Shanghai 200335, China
- Correspondence:
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Phosphoproteome profiling of hippocampal synaptic plasticity. Biochem Biophys Res Commun 2022; 626:92-99. [DOI: 10.1016/j.bbrc.2022.07.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 06/26/2022] [Accepted: 07/14/2022] [Indexed: 11/17/2022]
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Ahammad RU, Nishioka T, Yoshimoto J, Kannon T, Amano M, Funahashi Y, Tsuboi D, Faruk MO, Yamahashi Y, Yamada K, Nagai T, Kaibuchi K. KANPHOS: A Database of Kinase-Associated Neural Protein Phosphorylation in the Brain. Cells 2021; 11:47. [PMID: 35011609 PMCID: PMC8750479 DOI: 10.3390/cells11010047] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/19/2021] [Accepted: 12/21/2021] [Indexed: 12/15/2022] Open
Abstract
Protein phosphorylation plays critical roles in a variety of intracellular signaling pathways and physiological functions that are controlled by neurotransmitters and neuromodulators in the brain. Dysregulation of these signaling pathways has been implicated in neurodevelopmental disorders, including autism spectrum disorder, attention deficit hyperactivity disorder and schizophrenia. While recent advances in mass spectrometry-based proteomics have allowed us to identify approximately 280,000 phosphorylation sites, it remains largely unknown which sites are phosphorylated by which kinases. To overcome this issue, previously, we developed methods for comprehensive screening of the target substrates of given kinases, such as PKA and Rho-kinase, upon stimulation by extracellular signals and identified many candidate substrates for specific kinases and their phosphorylation sites. Here, we developed a novel online database to provide information about the phosphorylation signals identified by our methods, as well as those previously reported in the literature. The "KANPHOS" (Kinase-Associated Neural Phospho-Signaling) database and its web portal were built based on a next-generation XooNIps neuroinformatics tool. To explore the functionality of the KANPHOS database, we obtained phosphoproteomics data for adenosine-A2A-receptor signaling and its downstream MAPK-mediated signaling in the striatum/nucleus accumbens, registered them in KANPHOS, and analyzed the related pathways.
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Grants
- JP18dm0207005, JP21dm0207075, JP21wm0425017 and JP21wm0425008 Japan Agency for Medical Research and Development
- JP16K18393, JP17H01380, JP17K07383, JP17H02220, JP17K19483, JP18K14849, JP19K16370, JP21K06428 and JP21K06427 Japan Society for the Promotion of Science
- JP17H05561, JP19H05209 and JP21H00196 Ministry of Education, Culture, Sports, Science and Technology
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Affiliation(s)
- Rijwan Uddin Ahammad
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsurumai, Nagoya 466-8550, Japan
| | - Tomoki Nishioka
- Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Japan
| | - Junichiro Yoshimoto
- Division of Information Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Takayuki Kannon
- Department of Bioinformatics and Genomics, Graduate School of Advanced Preventive Medical Science, Kanazawa University, Kanazawa 920-8640, Japan
| | - Mutsuki Amano
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsurumai, Nagoya 466-8550, Japan
| | - Yasuhiro Funahashi
- Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Japan
| | - Daisuke Tsuboi
- Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Japan
| | - Md Omar Faruk
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsurumai, Nagoya 466-8550, Japan
| | - Yukie Yamahashi
- Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Japan
| | - Kiyofumi Yamada
- Department of Neuropsychopharmacology and Hospital Pharmacy, Graduate School of Medicine, Nagoya University, 65 Tsurumai, Nagoya 466-8550, Japan
| | - Taku Nagai
- Division of Behavioral Neuropharmacology, International Center for Brain Science (ICBS), Fujita Health University, Toyoake 470-1192, Japan
| | - Kozo Kaibuchi
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsurumai, Nagoya 466-8550, Japan
- Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Japan
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A phosphoproteomics study reveals a defined genetic program for neural lineage commitment of neural stem cells induced by olfactory ensheathing cell-conditioned medium. Pharmacol Res 2021; 172:105797. [PMID: 34352399 DOI: 10.1016/j.phrs.2021.105797] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/26/2021] [Accepted: 07/30/2021] [Indexed: 11/23/2022]
Abstract
Since both Olfactory ensheathing cells (OECs) and neural stem cells (NSCs) have shown certain efficacy in the cellular therapy of nerve injury and disease, there have been a series of investigations in recent years looking at the co-culture of NSCs and OECs. Protein phosphorylation forms the basis for identifying a variety of cellular signaling pathways responsible for regulating the self-renewal and differentiation of NSCs induced by OECs. To better understand the signaling cascades in the early phases of OEC-induced NSC differentiation, changes in the NSC proteome and phosphoproteome during the first 24 h were determined using dimethyl labeling and TiO2 phosphorylation enrichment coupled with Liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 565 proteins and 2511 phosphorylation sites were identified. According to quantitative phosphoproteomics analyses of NSC differentiation induced by OECs during the first 12 and 24 h, it was speculated that there were at least two different signal waves: one peaking within 12 h after stimulation and the second upsurge after 24 h. In addition to understanding the dynamics of the proteome and phosphoproteome in the early stages of NSC differentiation, our analyses identified a key role of the TGF-β3 protein secreted by OECs, which may be an initiating factor that promotes differentiation of NSCs into neurons induced by OECs. These findings not only redemonstrated a OECs-based therapeutic strategy in cell therapy, but also added a node to the regulatory network for the neural lineage commitment of NSCs induced by OECs.
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Proteomic Analysis Unveils Expressional Changes in Cytoskeleton- and Synaptic Plasticity-Associated Proteins in Rat Brain Six Months after Withdrawal from Morphine. Life (Basel) 2021; 11:life11070683. [PMID: 34357055 PMCID: PMC8304287 DOI: 10.3390/life11070683] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/28/2021] [Accepted: 07/10/2021] [Indexed: 11/17/2022] Open
Abstract
Drug withdrawal is associated with abstinence symptoms including deficits in cognitive functions that may persist even after prolonged discontinuation of drug intake. Cognitive deficits are, at least partially, caused by alterations in synaptic plasticity but the precise molecular mechanisms have not yet been fully identified. In the present study, changes in proteomic and phosphoproteomic profiles of selected brain regions (cortex, hippocampus, striatum, and cerebellum) from rats abstaining for six months after cessation of chronic treatment with morphine were determined by label-free quantitative (LFQ) proteomic analysis. Interestingly, prolonged morphine withdrawal was found to be associated especially with alterations in protein phosphorylation and to a lesser extent in protein expression. Gene ontology (GO) term analysis revealed enrichment in biological processes related to synaptic plasticity, cytoskeleton organization, and GTPase activity. More specifically, significant changes were observed in proteins localized in synaptic vesicles (e.g., synapsin-1, SV2a, Rab3a), in the active zone of the presynaptic nerve terminal (e.g., Bassoon, Piccolo, Rims1), and in the postsynaptic density (e.g., cadherin 13, catenins, Arhgap35, Shank3, Arhgef7). Other differentially phosphorylated proteins were associated with microtubule dynamics (microtubule-associated proteins, Tppp, collapsin response mediator proteins) and the actin–spectrin network (e.g., spectrins, adducins, band 4.1-like protein 1). Taken together, a six-month morphine withdrawal was manifested by significant alterations in the phosphorylation of synaptic proteins. The altered phosphorylation patterns modulating the function of synaptic proteins may contribute to long-term neuroadaptations induced by drug use and withdrawal.
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Lukinović V, Biggar KK. Deconvoluting complex protein interaction networks through reductionist strategies in peptide biochemistry: Modern approaches and research questions. Comp Biochem Physiol B Biochem Mol Biol 2021; 256:110616. [PMID: 34000427 DOI: 10.1016/j.cbpb.2021.110616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 05/06/2021] [Accepted: 05/12/2021] [Indexed: 12/12/2022]
Abstract
Following the decoding of the first human genome, researchers have vastly improved their understanding of cell biology and its regulation. As a result, it has become clear that it is not merely genetic information, but the aberrant changes in the functionality and connectivity of its encoded proteins that drive cell response to periods of stress and external cues. Therefore, proper utilization of refined methods that help to describe protein signalling or regulatory networks (i.e., functional connectivity), can help us understand how change in the signalling landscape effects the cell. However, given the vast complexity in 'how and when' proteins communicate or interact with each other, it is extremely difficult to define, characterize, and understand these interaction networks in a tangible manner. Herein lies the challenge of tackling the functional proteome; its regulation is encoded in multiple layers of interaction, chemical modification and cell compartmentalization. To address and refine simple research questions, modern reductionist strategies in protein biochemistry have successfully used peptide-based experiments; their summation helping to simplify the overall complexity of these protein interaction networks. In this way, peptides are powerful tools used in fundamental research that can be readily applied to comparative biochemical research. Understanding and defining how proteins interact is one of the key aspects towards understanding how the proteome functions. To date, reductionist peptide-based research has helped to address a wide range of proteome-related research questions, including the prediction of enzymes substrates, identification of posttranslational modifications, and the annotation of protein interaction partners. Peptide arrays have been used to identify the binding specificity of reader domains, which are able to recognise the posttranslational modifications; forming dynamic protein interactions that are dependent on modification state. Finally, representing one of the fastest growing classes of inhibitor molecules, peptides are now begin explored as "disruptors" of protein-protein interactions or enzyme activity. Collectively, this review will discuss the use of peptides, peptide arrays, peptide-oriented computational biochemistry as modern reductionist strategies in deconvoluting the functional proteome.
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Affiliation(s)
- Valentina Lukinović
- Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Kyle K Biggar
- Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.
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Serine/Threonine Phosphatases in LTP: Two B or Not to Be the Protein Synthesis Blocker-Induced Impairment of Early Phase. Int J Mol Sci 2021; 22:ijms22094857. [PMID: 34064311 PMCID: PMC8125358 DOI: 10.3390/ijms22094857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 04/27/2021] [Accepted: 04/30/2021] [Indexed: 11/25/2022] Open
Abstract
Dephosphorylation of target proteins at serine/threonine residues is one of the most crucial mechanisms regulating their activity and, consequently, the cellular functions. The role of phosphatases in synaptic plasticity, especially in long-term depression or depotentiation, has been reported. We studied serine/threonine phosphatase activity during the protein synthesis blocker (PSB)-induced impairment of long-term potentiation (LTP). Established protein phosphatase 2B (PP2B, calcineurin) inhibitor cyclosporin A prevented the LTP early phase (E-LTP) decline produced by pretreatment of hippocampal slices with cycloheximide or anisomycin. For the first time, we directly measured serine/threonine phosphatase activity during E-LTP, and its significant increase in PSB-treated slices was demonstrated. Nitric oxide (NO) donor SNAP also heightened phosphatase activity in the same manner as PSB, and simultaneous application of anisomycin + SNAP had no synergistic effect. Direct measurement of the NO production in hippocampal slices by the NO-specific fluorescent probe DAF-FM revealed that PSBs strongly stimulate the NO concentration in all studied brain areas: CA1, CA3, and dentate gyrus (DG). Cyclosporin A fully abolished the PSB-induced NO production in the hippocampus, suggesting a close relationship between nNOS and PP2B activity. Surprisingly, cyclosporin A alone impaired short-term plasticity in CA1 by decreasing paired-pulse facilitation, which suggests bi-directionality of the influences of PP2B in the hippocampus. In conclusion, we proposed a minimal model of signaling events that occur during LTP induction in normal conditions and the PSB-treated slices.
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van Gelder CAGH, Altelaar M. Neuroproteomics of the Synapse: Subcellular Quantification of Protein Networks and Signaling Dynamics. Mol Cell Proteomics 2021; 20:100087. [PMID: 33933679 PMCID: PMC8167277 DOI: 10.1016/j.mcpro.2021.100087] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/21/2021] [Accepted: 04/26/2021] [Indexed: 01/21/2023] Open
Abstract
One of the most fascinating features of the brain is its ability to adapt to its surroundings. Synaptic plasticity, the dynamic mechanism of functional and structural alterations in synaptic strength, is essential for brain functioning and underlies a variety of processes such as learning and memory. Although the molecular mechanisms underlying such rapid plasticity are not fully understood, a consensus exists on the important role of proteins. The study of these neuronal proteins using neuroproteomics has increased rapidly in the last decades, and advancements in MS-based proteomics have broadened our understanding of neuroplasticity exponentially. In this review, we discuss the trends in MS-based neuroproteomics for the study of synaptic protein-protein interactions and protein signaling dynamics, with a focus on sample types, different labeling and enrichment approaches, and data analysis and interpretation. We highlight studies from the last 5 years, with a focus on synapse structure, composition, functioning, or signaling and finally discuss some recent developments that could further advance the field of neuroproteomics.
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Affiliation(s)
- Charlotte A G H van Gelder
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands; Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Maarten Altelaar
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands; Netherlands Proteomics Center, Utrecht, The Netherlands.
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Farahi N, Lazar T, Wodak SJ, Tompa P, Pancsa R. Integration of Data from Liquid-Liquid Phase Separation Databases Highlights Concentration and Dosage Sensitivity of LLPS Drivers. Int J Mol Sci 2021; 22:ijms22063017. [PMID: 33809541 PMCID: PMC8002189 DOI: 10.3390/ijms22063017] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 12/13/2022] Open
Abstract
Liquid–liquid phase separation (LLPS) is a molecular process that leads to the formation of membraneless organelles, representing functionally specialized liquid-like cellular condensates formed by proteins and nucleic acids. Integrating the data on LLPS-associated proteins from dedicated databases revealed only modest agreement between them and yielded a high-confidence dataset of 89 human LLPS drivers. Analysis of the supporting evidence for our dataset uncovered a systematic and potentially concerning difference between protein concentrations used in a good fraction of the in vitro LLPS experiments, a key parameter that governs the phase behavior, and the proteomics-derived cellular abundance levels of the corresponding proteins. Closer scrutiny of the underlying experimental data enabled us to offer a sound rationale for this systematic difference, which draws on our current understanding of the cellular organization of the proteome and the LLPS process. In support of this rationale, we find that genes coding for our human LLPS drivers tend to be dosage-sensitive, suggesting that their cellular availability is tightly regulated to preserve their functional role in direct or indirect relation to condensate formation. Our analysis offers guideposts for increasing agreement between in vitro and in vivo studies, probing the roles of proteins in LLPS.
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Affiliation(s)
- Nazanin Farahi
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
- Department of Biology, Technical University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Tamas Lazar
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Shoshana J. Wodak
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Peter Tompa
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
- Institute of Enzymology, Research Centre for Natural Sciences, 1117 Budapest, Hungary
- Correspondence: (P.T.); (R.P.)
| | - Rita Pancsa
- Institute of Enzymology, Research Centre for Natural Sciences, 1117 Budapest, Hungary
- Correspondence: (P.T.); (R.P.)
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15
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Xu Y, Song X, Wang D, Wang Y, Li P, Li J. Proteomic insights into synaptic signaling in the brain: the past, present and future. Mol Brain 2021; 14:37. [PMID: 33596935 PMCID: PMC7888154 DOI: 10.1186/s13041-021-00750-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 02/09/2021] [Indexed: 12/29/2022] Open
Abstract
Chemical synapses in the brain connect neurons to form neural circuits, providing the structural and functional bases for neural communication. Disrupted synaptic signaling is closely related to a variety of neurological and psychiatric disorders. In the past two decades, proteomics has blossomed as a versatile tool in biological and biomedical research, rendering a wealth of information toward decoding the molecular machinery of life. There is enormous interest in employing proteomic approaches for the study of synapses, and substantial progress has been made. Here, we review the findings of proteomic studies of chemical synapses in the brain, with special attention paid to the key players in synaptic signaling, i.e., the synaptic protein complexes and their post-translational modifications. Looking toward the future, we discuss the technological advances in proteomics such as data-independent acquisition mass spectrometry (DIA-MS), cross-linking in combination with mass spectrometry (CXMS), and proximity proteomics, along with their potential to untangle the mystery of how the brain functions at the molecular level. Last but not least, we introduce the newly developed synaptomic methods. These methods and their successful applications marked the beginnings of the synaptomics era.
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Affiliation(s)
- Yalan Xu
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Xiuyue Song
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Dong Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Yin Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China
| | - Jing Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Medical College, Qingdao University, Qingdao, 266021, China.
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16
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Molecular Diversity of Glutamatergic and GABAergic Synapses from Multiplexed Fluorescence Imaging. eNeuro 2021; 8:ENEURO.0286-20.2020. [PMID: 33355295 PMCID: PMC7877457 DOI: 10.1523/eneuro.0286-20.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 11/25/2020] [Accepted: 12/07/2020] [Indexed: 01/01/2023] Open
Abstract
Neuronal synapses contain hundreds of different protein species important for regulating signal transmission. Characterizing differential expression profiles of proteins within synapses in distinct regions of the brain has revealed a high degree of synaptic diversity defined by unique molecular organization. Multiplexed imaging of in vitro rat primary hippocampal culture models at single synapse resolution offers new opportunities for exploring synaptic reorganization in response to chemical and genetic perturbations. Here, we combine 12-color multiplexed fluorescence imaging with quantitative image analysis and machine learning to identify novel synaptic subtypes within excitatory and inhibitory synapses based on the expression profiles of major synaptic components. We characterize differences in the correlated expression of proteins within these subtypes and we examine how the distribution of these synapses is modified following induction of synaptic plasticity. Under chronic suppression of neuronal activity, phenotypic characterization revealed coordinated increases in both excitatory and inhibitory protein levels without changes in the distribution of synaptic subtypes, suggesting concerted events targeting glutamatergic and GABAergic synapses. Our results offer molecular insight into the mechanisms of synaptic plasticity.
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17
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Energetics of stochastic BCM type synaptic plasticity and storing of accurate information. J Comput Neurosci 2021; 49:71-106. [PMID: 33528721 PMCID: PMC8046702 DOI: 10.1007/s10827-020-00775-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/04/2020] [Accepted: 12/13/2020] [Indexed: 11/10/2022]
Abstract
Excitatory synaptic signaling in cortical circuits is thought to be metabolically expensive. Two fundamental brain functions, learning and memory, are associated with long-term synaptic plasticity, but we know very little about energetics of these slow biophysical processes. This study investigates the energy requirement of information storing in plastic synapses for an extended version of BCM plasticity with a decay term, stochastic noise, and nonlinear dependence of neuron’s firing rate on synaptic current (adaptation). It is shown that synaptic weights in this model exhibit bistability. In order to analyze the system analytically, it is reduced to a simple dynamic mean-field for a population averaged plastic synaptic current. Next, using the concepts of nonequilibrium thermodynamics, we derive the energy rate (entropy production rate) for plastic synapses and a corresponding Fisher information for coding presynaptic input. That energy, which is of chemical origin, is primarily used for battling fluctuations in the synaptic weights and presynaptic firing rates, and it increases steeply with synaptic weights, and more uniformly though nonlinearly with presynaptic firing. At the onset of synaptic bistability, Fisher information and memory lifetime both increase sharply, by a few orders of magnitude, but the plasticity energy rate changes only mildly. This implies that a huge gain in the precision of stored information does not have to cost large amounts of metabolic energy, which suggests that synaptic information is not directly limited by energy consumption. Interestingly, for very weak synaptic noise, such a limit on synaptic coding accuracy is imposed instead by a derivative of the plasticity energy rate with respect to the mean presynaptic firing, and this relationship has a general character that is independent of the plasticity type. An estimate for primate neocortex reveals that a relative metabolic cost of BCM type synaptic plasticity, as a fraction of neuronal cost related to fast synaptic transmission and spiking, can vary from negligible to substantial, depending on the synaptic noise level and presynaptic firing.
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18
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Agarwal M, Alam MR, Haider MK, Malik MZ, Kim DK. Alzheimer's Disease: An Overview of Major Hypotheses and Therapeutic Options in Nanotechnology. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 11:E59. [PMID: 33383712 PMCID: PMC7823376 DOI: 10.3390/nano11010059] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/18/2020] [Accepted: 12/24/2020] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD), a progressively fatal neurodegenerative disorder, is the most prominent form of dementia found today. Patients suffering from Alzheimer's begin to show the signs and symptoms, like decline in memory and cognition, long after the cellular damage has been initiated in their brain. There are several hypothesis for the neurodegeneration process; however, the lack of availability of in vivo models makes the recapitulation of AD in humans impossible. Moreover, the drugs currently available in the market serve to alleviate the symptoms and there is no cure for the disease. There have been two major hurdles in the process of finding the same-the inefficiency in cracking the complexity of the disease pathogenesis and the inefficiency in delivery of drugs targeted for AD. This review discusses the different drugs that have been designed over the recent years and the drug delivery options in the field of nanotechnology that have been found most feasible in surpassing the blood-brain barrier (BBB) and reaching the brain.
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Affiliation(s)
- Mugdha Agarwal
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida 201309, India;
| | - Mohammad Rizwan Alam
- Department of Medical Genetics, School of Medicine, Keimyung University, Daegu 42601, Korea;
| | | | - Md. Zubbair Malik
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Dae-Kwang Kim
- Department of Medical Genetics, School of Medicine, Keimyung University, Daegu 42601, Korea;
- Hanvit Institute for Medical Genetics, Daegu 42601, Korea
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19
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Cai Q, Zeng M, Wu X, Wu H, Zhan Y, Tian R, Zhang M. CaMKIIα-driven, phosphatase-checked postsynaptic plasticity via phase separation. Cell Res 2020; 31:37-51. [PMID: 33235361 DOI: 10.1038/s41422-020-00439-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 10/27/2020] [Indexed: 11/09/2022] Open
Abstract
Ca2+/calmodulin-dependent kinase IIα (CaMKIIα) is essential for synaptic plasticity and learning by decoding synaptic Ca2+ oscillations. Despite decades of extensive research, new mechanisms underlying CaMKIIα's function in synapses are still being discovered. Here, we discover that Shank3 is a specific binding partner for autoinhibited CaMKIIα. We demonstrate that Shank3 and GluN2B, via combined actions of Ca2+ and phosphatases, reciprocally bind to CaMKIIα. Under basal condition, CaMKIIα is recruited to the Shank3 subcompartment of postsynaptic density (PSD) via phase separation. Rise of Ca2+ concentration induces GluN2B-mediated recruitment of active CaMKIIα and formation of the CaMKIIα/GluN2B/PSD-95 condensates, which are autonomously dispersed upon Ca2+ removal. Protein phosphatases control the Ca2+-dependent shuttling of CaMKIIα between the two PSD subcompartments and PSD condensate formation. Activation of CaMKIIα further enlarges the PSD assembly and induces structural LTP. Thus, Ca2+-induced and phosphatase-checked shuttling of CaMKIIα between distinct PSD nano-domains can regulate phase separation-mediated PSD assembly and synaptic plasticity.
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Affiliation(s)
- Qixu Cai
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Menglong Zeng
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.,McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Xiandeng Wu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Haowei Wu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Yumeng Zhan
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Ruijun Tian
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China. .,Center of Systems Biology and Human Health, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
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20
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Murtaza N, Uy J, Singh KK. Emerging proteomic approaches to identify the underlying pathophysiology of neurodevelopmental and neurodegenerative disorders. Mol Autism 2020; 11:27. [PMID: 32317014 PMCID: PMC7171839 DOI: 10.1186/s13229-020-00334-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/06/2020] [Indexed: 12/18/2022] Open
Abstract
Proteomics is the large-scale study of the total protein content and their overall function within a cell through multiple facets of research. Advancements in proteomic methods have moved past the simple quantification of proteins to the identification of post-translational modifications (PTMs) and the ability to probe interactions between these proteins, spatially and temporally. Increased sensitivity and resolution of mass spectrometers and sample preparation protocols have drastically reduced the large amount of cells required and the experimental variability that had previously hindered its use in studying human neurological disorders. Proteomics offers a new perspective to study the altered molecular pathways and networks that are associated with autism spectrum disorders (ASD). The differences between the transcriptome and proteome, combined with the various types of post-translation modifications that regulate protein function and localization, highlight a novel level of research that has not been appropriately investigated. In this review, we will discuss strategies using proteomics to study ASD and other neurological disorders, with a focus on how these approaches can be combined with induced pluripotent stem cell (iPSC) studies. Proteomic analysis of iPSC-derived neurons have already been used to measure changes in the proteome caused by patient mutations, analyze changes in PTMs that resulted in altered biological pathways, and identify potential biomarkers. Further advancements in both proteomic techniques and human iPSC differentiation protocols will continue to push the field towards better understanding ASD disease pathophysiology. Proteomics using iPSC-derived neurons from individuals with ASD offers a window for observing the altered proteome, which is necessary in the future development of therapeutics against specific targets.
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Affiliation(s)
- Nadeem Murtaza
- Stem Cell and Cancer Research Institute, Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Jarryll Uy
- Stem Cell and Cancer Research Institute, Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Karun K Singh
- Stem Cell and Cancer Research Institute, Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, ON, L8N 3Z5, Canada.
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21
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Classen J, Saarloos I, Meijer M, Sullivan PF, Verhage M. A Munc18-1 mutant mimicking phosphorylation by Down Syndrome-related kinase Dyrk1a supports normal synaptic transmission and promotes recovery after intense activity. Sci Rep 2020; 10:3181. [PMID: 32081899 PMCID: PMC7035266 DOI: 10.1038/s41598-020-59757-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 01/31/2020] [Indexed: 11/24/2022] Open
Abstract
Phosphorylation of Munc18-1 (Stxbp1), a presynaptic organizer of synaptic vesicle fusion, is a powerful mechanism to regulate synaptic strength. Munc18-1 is a proposed substrate for the Down Syndrome-related kinase dual-specificity tyrosine phosphorylation-regulate kinase 1a (Dyrk1a) and mutations in both genes cause intellectual disability. However, the functional consequences of Dyrk1a-dependent phosphorylation of Munc18-1 for synapse function are unknown. Here, we show that the proposed Munc18-1 phosphorylation site, T479, is among the highly constrained phosphorylation sites in the coding regions of the gene and is also located within a larger constrained coding region. We confirm that Dyrk1a phosphorylates Munc18-1 at T479. Patch-clamp physiology in conditional null mutant hippocampal neurons expressing Cre and either wildtype, or mutants mimicking or preventing phosphorylation, revealed that synaptic transmission is similar among the three groups: frequency/amplitude of mEPSCs, evoked EPSCs, paired pulse plasticity, rundown kinetics upon intense activity and the readily releasable pool. However, synapses expressing the phosphomimic mutant responded to intense activity with more pronounced facilitation. These data indicate that Dyrk1a-dependent Munc18-1 phosphorylation has a minor impact on synaptic transmission, only after intense activity, and that the role of genetic variation in both genes in intellectual disability may be through different mechanisms.
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Affiliation(s)
- Jessica Classen
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, VU University, 1081, HV, Amsterdam, The Netherlands
| | - Ingrid Saarloos
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, VU University, 1081, HV, Amsterdam, The Netherlands
| | - Marieke Meijer
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, VU University, 1081, HV, Amsterdam, The Netherlands
| | - Patrick F Sullivan
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Nobels väg 12A, PO Box 281, 171 77, Stockholm, Sweden
- Departments of Genetics and Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Matthijs Verhage
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, VU University, 1081, HV, Amsterdam, The Netherlands.
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22
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Regulation of Multifunctional Calcium/Calmodulin Stimulated Protein Kinases by Molecular Targeting. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:649-679. [PMID: 31646529 DOI: 10.1007/978-3-030-12457-1_26] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Multifunctional calcium/calmodulin-stimulated protein kinases control a broad range of cellular functions in a multitude of cell types. This family of kinases contain several structural similarities and all are regulated by phosphorylation, which either activates, inhibits or modulates their kinase activity. As these protein kinases are widely or ubiquitously expressed, and yet regulate a broad range of different cellular functions, additional levels of regulation exist that control these cell-specific functions. Of particular importance for this specificity of function for multifunctional kinases is the expression of specific binding proteins that mediate molecular targeting. These molecular targeting mechanisms allow pools of kinase in different cells, or parts of a cell, to respond differently to activation and produce different functional outcomes.
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23
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Grant SGN. Synapse diversity and synaptome architecture in human genetic disorders. Hum Mol Genet 2019; 28:R219-R225. [PMID: 31348488 PMCID: PMC6872429 DOI: 10.1093/hmg/ddz178] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/18/2019] [Accepted: 07/18/2019] [Indexed: 12/03/2022] Open
Abstract
Over 130 brain diseases are caused by mutations that disrupt genes encoding the proteome of excitatory synapses. These include neurological and psychiatric disorders with early and late onset such as autism, schizophrenia and depression and many other rarer conditions. The proteome of synapses is highly complex with over 1000 conserved proteins which are differentially expressed generating a vast, potentially unlimited, number of synapse types. The diversity of synapses and their location in the brain are described by the synaptome. A recent study has mapped the synaptome across the mouse brain, revealing that synapse diversity is distributed into an anatomical architecture observed at scales from individual dendrites to the whole systems level. The synaptome architecture is built from the hierarchical expression and assembly of proteins into complexes and supercomplexes which are distributed into different synapses. Mutations in synapse proteins change the synaptome architecture leading to behavioral phenotypes. Mutations in the mechanisms regulating the hierarchical assembly of the synaptome, including transcription and proteostasis, may also change synapse diversity and synaptome architecture. The logic of synaptome hierarchical assembly provides a mechanistic framework that explains how diverse genetic disorders can converge on synapses in different brain circuits to produce behavioral phenotypes.
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Affiliation(s)
- Seth G N Grant
- Centre for Clinical Brain Science, Edinburgh University, Edinburgh, UK
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24
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Kumar A, Narayanan V, Sekhar A. Characterizing Post-Translational Modifications and Their Effects on Protein Conformation Using NMR Spectroscopy. Biochemistry 2019; 59:57-73. [PMID: 31682116 DOI: 10.1021/acs.biochem.9b00827] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The diversity of the cellular proteome substantially exceeds the number of genes coded by the DNA of an organism because one or more residues in a majority of eukaryotic proteins are post-translationally modified (PTM) by the covalent conjugation of specific chemical groups. We now know that PTMs alter protein conformation and function in ways that are not entirely understood at the molecular level. NMR spectroscopy has been particularly successful as an analytical tool in elucidating the themes underlying the structural role of PTMs. In this Perspective, we focus on the NMR-based characterization of three abundant PTMs: phosphorylation, acetylation, and glycosylation. We detail NMR methods that have found success in detecting these modifications at a site-specific level. We also highlight NMR studies that have mapped the conformational changes ensuing from these PTMs as well as evaluated their relation to function. The NMR toolbox is expanding rapidly with experiments available to probe not only the average structure of biomolecules but also how this structure changes with time on time scales ranging from picoseconds to seconds. The atomic resolution insights into the biomolecular structure, dynamics, and mechanism accessible from NMR spectroscopy ensure that NMR will continue to be at the forefront of research in the structural biology of PTMs.
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Affiliation(s)
- Ajith Kumar
- Molecular Biophysics Unit , Indian Institute of Science , Bangalore 560 012 , India
| | - Vaishali Narayanan
- Molecular Biophysics Unit , Indian Institute of Science , Bangalore 560 012 , India
| | - Ashok Sekhar
- Molecular Biophysics Unit , Indian Institute of Science , Bangalore 560 012 , India
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25
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Velasco L, Dublang L, Moro F, Muga A. The Complex Phosphorylation Patterns that Regulate the Activity of Hsp70 and Its Cochaperones. Int J Mol Sci 2019; 20:ijms20174122. [PMID: 31450862 PMCID: PMC6747476 DOI: 10.3390/ijms20174122] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 08/21/2019] [Accepted: 08/22/2019] [Indexed: 12/26/2022] Open
Abstract
Proteins must fold into their native structure and maintain it during their lifespan to display the desired activity. To ensure proper folding and stability, and avoid generation of misfolded conformations that can be potentially cytotoxic, cells synthesize a wide variety of molecular chaperones that assist folding of other proteins and avoid their aggregation, which unfortunately is unavoidable under acute stress conditions. A protein machinery in metazoa, composed of representatives of the Hsp70, Hsp40, and Hsp110 chaperone families, can reactivate protein aggregates. We revised herein the phosphorylation sites found so far in members of these chaperone families and the functional consequences associated with some of them. We also discuss how phosphorylation might regulate the chaperone activity and the interaction of human Hsp70 with its accessory and client proteins. Finally, we present the information that would be necessary to decrypt the effect that post-translational modifications, and especially phosphorylation, could have on the biological activity of the Hsp70 system, known as the “chaperone code”.
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Affiliation(s)
- Lorea Velasco
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain
| | - Leire Dublang
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain
| | - Fernando Moro
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain.
| | - Arturo Muga
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain.
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26
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Karbowski J. Metabolic constraints on synaptic learning and memory. J Neurophysiol 2019; 122:1473-1490. [PMID: 31365284 DOI: 10.1152/jn.00092.2019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Dendritic spines, the carriers of long-term memory, occupy a small fraction of cortical space, and yet they are the major consumers of brain metabolic energy. What fraction of this energy goes for synaptic plasticity, correlated with learning and memory? It is estimated here based on neurophysiological and proteomic data for rat brain that, depending on the level of protein phosphorylation, the energy cost of synaptic plasticity constitutes a small fraction of the energy used for fast excitatory synaptic transmission, typically 4.0-11.2%. Next, this study analyzes a metabolic cost of new learning and its memory trace in relation to the cost of prior memories, using a class of cascade models of synaptic plasticity. It is argued that these models must contain bidirectional cyclic motifs, related to protein phosphorylation, to be compatible with basic thermodynamic principles. For most investigated parameters longer memories generally require proportionally more energy to store. The exceptions are the parameters controlling the speed of molecular transitions (e.g., ATP-driven phosphorylation rate), for which memory lifetime per invested energy can increase progressively for longer memories. Furthermore, in general, a memory trace decouples dynamically from a corresponding synaptic metabolic rate such that the energy expended on new learning and its memory trace constitutes in most cases only a small fraction of the baseline energy associated with prior memories. Taken together, these empirical and theoretical results suggest a metabolic efficiency of synaptically stored information.NEW & NOTEWORTHY Learning and memory involve a sequence of molecular events in dendritic spines called synaptic plasticity. These events are physical in nature and require energy, which has to be supplied by ATP molecules. However, our knowledge of the energetics of these processes is very poor. This study estimates the empirical energy cost of synaptic plasticity and considers theoretically a metabolic rate of learning and its memory trace in a class of cascade models of synaptic plasticity.
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Affiliation(s)
- Jan Karbowski
- Institute of Applied Mathematics and Mechanics, University of Warsaw, Warsaw, Poland.,Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Warsaw, Poland
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27
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Grant SGN. The Synaptomic Theory of Behavior and Brain Disease. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2019; 83:45-56. [PMID: 30886054 DOI: 10.1101/sqb.2018.83.037887] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The purpose of this article is to outline a new molecular and synaptic theory of behavior called the "synaptomic theory," named because it is centered on the synaptome-the complement of synapses in the brain. Synaptomic theory posits that synapses are structures of high molecular complexity and vast diversity that are observable in maps of the brain and that these synaptome maps are fundamental to behavior. Synaptome maps are a means of writing or storing information that can be retrieved by the patterns of activity that stimulate synapses. Synaptome maps have the capacity to store large amounts of information, including multiple representations within the same map. The dynamic properties of synapses allow synaptome maps to store dynamic sequences of representations that could serve to program behavioral sequences. Synaptome maps are genetically programmed and experience-dependent, thereby storing innate and learned behaviors, respectively. Although learning occurs by modification of the synapse proteome, it does not require long-term potentiation (LTP) of synaptic weight or growth of new synapses, and the theory predicts that LTP modulates information recall. The spatial architecture of synaptome maps arise from an underlying molecular hierarchy linking the genome to the supramolecular assembly of proteins into complexes and supercomplexes. This molecular hierarchy can explain how genome evolution results in the behavioral repertoire of the organism. Mutations disrupting this molecular hierarchy change the architecture of synaptome maps, potentially accounting for the behavioral phenotypes associated with neurological and psychiatric disorders.
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Affiliation(s)
- Seth G N Grant
- Genes to Cognition Program, Centre for Clinical Brain Sciences, Edinburgh University, Edinburgh BioQuarter, Edinburgh EH16 4SB, United Kingdom
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Coba MP. Regulatory mechanisms in postsynaptic phosphorylation networks. Curr Opin Struct Biol 2019; 54:86-94. [PMID: 30807903 PMCID: PMC7018365 DOI: 10.1016/j.sbi.2019.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 12/19/2018] [Accepted: 01/06/2019] [Indexed: 12/11/2022]
Abstract
The modulation of the postsynaptic signaling machinery by protein phosphorylation has attracted much interest since it is key for the understanding of the regulation of a variety of synaptic functions. While advances in mass spectrometry have allowed us to begin performing large-scale analysis of protein phosphorylation in components of the PSD, the systematic collection of datasets and their functional significance within the context of regulatory signaling networks is in its infancy. Here, we will focus on the composition of the PSD phosphoproteome describing kinase, phosphatase, and protein domain modules involved in the regulation of phosphorylation signaling. We will discuss the impact of synaptic plasticity mechanisms such as long-term potentiation (LTP) in mammalian kinomes and describe the general rules of signaling organization in the PSD phosphoproteome.
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Affiliation(s)
- Marcelo P Coba
- Zilkha Neurogenetic Institute, Department of Psychiatry and Behavioral Sciences, University of Southern California, Los Angeles, CA, United States.
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Brzozowski JS, Skelding KA. The Multi-Functional Calcium/Calmodulin Stimulated Protein Kinase (CaMK) Family: Emerging Targets for Anti-Cancer Therapeutic Intervention. Pharmaceuticals (Basel) 2019; 12:ph12010008. [PMID: 30621060 PMCID: PMC6469190 DOI: 10.3390/ph12010008] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/02/2019] [Accepted: 01/04/2019] [Indexed: 01/25/2023] Open
Abstract
The importance of Ca2+ signalling in key events of cancer cell function and tumour progression, such as proliferation, migration, invasion and survival, has recently begun to be appreciated. Many cellular Ca2+-stimulated signalling cascades utilise the intermediate, calmodulin (CaM). The Ca2+/CaM complex binds and activates a variety of enzymes, including members of the multifunctional Ca2+/calmodulin-stimulated protein kinase (CaMK) family. These enzymes control a broad range of cancer-related functions in a multitude of tumour types. Herein, we explore the cancer-related functions of these kinases and discuss their potential as targets for therapeutic intervention.
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Affiliation(s)
- Joshua S Brzozowski
- Priority Research Centre for Cancer Research, Innovation and Translation, School of Biomedical Sciences and Pharmacy, Hunter Medical Research Institute (HMRI) and University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Kathryn A Skelding
- Priority Research Centre for Cancer Research, Innovation and Translation, School of Biomedical Sciences and Pharmacy, Hunter Medical Research Institute (HMRI) and University of Newcastle, Callaghan, NSW 2308, Australia.
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Phosphoproteomic identification and functional characterization of protein kinase substrates by 2D-DIGE and Phos-tag PAGE. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:57-61. [DOI: 10.1016/j.bbapap.2018.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 05/30/2018] [Accepted: 06/01/2018] [Indexed: 12/22/2022]
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Grant SGN. Synapse molecular complexity and the plasticity behaviour problem. Brain Neurosci Adv 2018; 2:2398212818810685. [PMID: 32166154 PMCID: PMC7058196 DOI: 10.1177/2398212818810685] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Indexed: 01/06/2023] Open
Abstract
Synapses are the hallmark of brain complexity and have long been thought of as simple connectors between neurons. We are now in an era in which we know the full complement of synapse proteins and this has created an existential crisis because the molecular complexity far exceeds the requirements of most simple models of synaptic function. Studies of the organisation of proteome complexity and its evolution provide surprising new insights that challenge existing dogma and promote the development of new theories about the origins and role of synapses in behaviour. The postsynaptic proteome of excitatory synapses is a structure with high molecular complexity and sophisticated computational properties that is disrupted in over 130 brain diseases. A key goal of 21st-century neuroscience is to develop comprehensive molecular datasets on the brain and develop theories that explain the molecular basis of behaviour.
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Affiliation(s)
- Seth G N Grant
- Genes to Cognition Programme, Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, UK
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Zhu F, Cizeron M, Qiu Z, Benavides-Piccione R, Kopanitsa MV, Skene NG, Koniaris B, DeFelipe J, Fransén E, Komiyama NH, Grant SGN. Architecture of the Mouse Brain Synaptome. Neuron 2018; 99:781-799.e10. [PMID: 30078578 PMCID: PMC6117470 DOI: 10.1016/j.neuron.2018.07.007] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 06/22/2018] [Accepted: 07/03/2018] [Indexed: 12/11/2022]
Abstract
Synapses are found in vast numbers in the brain and contain complex proteomes. We developed genetic labeling and imaging methods to examine synaptic proteins in individual excitatory synapses across all regions of the mouse brain. Synapse catalogs were generated from the molecular and morphological features of a billion synapses. Each synapse subtype showed a unique anatomical distribution, and each brain region showed a distinct signature of synapse subtypes. Whole-brain synaptome cartography revealed spatial architecture from dendritic to global systems levels and previously unknown anatomical features. Synaptome mapping of circuits showed correspondence between synapse diversity and structural and functional connectomes. Behaviorally relevant patterns of neuronal activity trigger spatiotemporal postsynaptic responses sensitive to the structure of synaptome maps. Areas controlling higher cognitive function contain the greatest synapse diversity, and mutations causing cognitive disorders reorganized synaptome maps. Synaptome technology and resources have wide-ranging application in studies of the normal and diseased brain.
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Affiliation(s)
- Fei Zhu
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK; UCL Institute of Neurology, Queen Square, WC1N 3BG London, UK
| | - Mélissa Cizeron
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK; Institut NeuroMyoGène, Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR-5310, INSERM U-1217, 69008 Lyon, France
| | - Zhen Qiu
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Ruth Benavides-Piccione
- Instituto Cajal (CSIC) 28002 Madrid, Centro de Tecnología Biomédica (UPM) 28223 Madrid; CIBERNED, ISCIII, 28031 Madrid, Spain
| | - Maksym V Kopanitsa
- Synome Ltd, Babraham Research Campus, Cambridge CB22 3AT, UK; UK Dementia Research Institute, Imperial College London, London W12 0NN, UK
| | - Nathan G Skene
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK; UCL Institute of Neurology, Queen Square, WC1N 3BG London, UK; Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Babis Koniaris
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Javier DeFelipe
- Instituto Cajal (CSIC) 28002 Madrid, Centro de Tecnología Biomédica (UPM) 28223 Madrid; CIBERNED, ISCIII, 28031 Madrid, Spain
| | - Erik Fransén
- Department of Computational Science and Technology, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, 10044 Stockholm, Sweden
| | - Noboru H Komiyama
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Seth G N Grant
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK.
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Feng Z, Zeng M, Chen X, Zhang M. Neuronal Synapses: Microscale Signal Processing Machineries Formed by Phase Separation? Biochemistry 2018; 57:2530-2539. [DOI: 10.1021/acs.biochem.8b00313] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zhe Feng
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Menglong Zeng
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xudong Chen
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
- Center of Systems Biology and Human Health, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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Coba MP, Ramaker MJ, Ho EV, Thompson SL, Komiyama NH, Grant SGN, Knowles JA, Dulawa SC. Dlgap1 knockout mice exhibit alterations of the postsynaptic density and selective reductions in sociability. Sci Rep 2018; 8:2281. [PMID: 29396406 PMCID: PMC5797244 DOI: 10.1038/s41598-018-20610-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 01/16/2018] [Indexed: 11/09/2022] Open
Abstract
The scaffold protein DLGAP1 is localized at the post-synaptic density (PSD) of glutamatergic neurons and is a component of supramolecular protein complexes organized by PSD95. Gain-of-function variants of DLGAP1 have been associated with obsessive-compulsive disorder (OCD), while haploinsufficient variants have been linked to autism spectrum disorder (ASD) and schizophrenia in human genetic studies. We tested male and female Dlgap1 wild type (WT), heterozygous (HT), and knockout (KO) mice in a battery of behavioral tests: open field, dig, splash, prepulse inhibition, forced swim, nest building, social approach, and sucrose preference. We also used biochemical approaches to examine the role of DLGAP1 in the organization of PSD protein complexes. Dlgap1 KO mice were most notable for disruption of protein interactions in the PSD, and deficits in sociability. Other behavioral measures were largely unaffected. Our data suggest that Dlgap1 knockout leads to PSD disruption and reduced sociability, consistent with reports of DLGAP1 haploinsufficient variants in schizophrenia and ASD.
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Affiliation(s)
- M P Coba
- Department of Psychiatry and the Behavioral Sciences, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, USA
| | - M J Ramaker
- Department of Psychiatry, University of California, San Diego, USA
| | - E V Ho
- Department of Psychiatry, University of California, San Diego, USA
| | - S L Thompson
- Department of Psychiatry, University of California, San Diego, USA
- Committee on Neurobiology, The University of Chicago, Chicago, USA
| | - N H Komiyama
- Genes to Cognition Program, Centre for Clinical Brain Sciences, Edinburgh University, Edinburgh, Scotland
| | - S G N Grant
- Genes to Cognition Program, Centre for Clinical Brain Sciences, Edinburgh University, Edinburgh, Scotland
| | - J A Knowles
- Department of Psychiatry and the Behavioral Sciences, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, USA
| | - S C Dulawa
- Department of Psychiatry, University of California, San Diego, USA.
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Zhu J, Zhou Q, Shang Y, Li H, Peng M, Ke X, Weng Z, Zhang R, Huang X, Li SS, Feng G, Lu Y, Zhang M. Synaptic Targeting and Function of SAPAPs Mediated by Phosphorylation-Dependent Binding to PSD-95 MAGUKs. Cell Rep 2017; 21:3781-3793. [DOI: 10.1016/j.celrep.2017.11.107] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 11/13/2017] [Accepted: 11/29/2017] [Indexed: 10/18/2022] Open
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Meijer M, Dörr B, Lammertse HC, Blithikioti C, van Weering JR, Toonen RF, Söllner TH, Verhage M. Tyrosine phosphorylation of Munc18-1 inhibits synaptic transmission by preventing SNARE assembly. EMBO J 2017; 37:300-320. [PMID: 29150433 PMCID: PMC5770875 DOI: 10.15252/embj.201796484] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 10/12/2017] [Accepted: 10/16/2017] [Indexed: 11/17/2022] Open
Abstract
Tyrosine kinases are important regulators of synaptic strength. Here, we describe a key component of the synaptic vesicle release machinery, Munc18‐1, as a phosphorylation target for neuronal Src family kinases (SFKs). Phosphomimetic Y473D mutation of a SFK phosphorylation site previously identified by brain phospho‐proteomics abolished the stimulatory effect of Munc18‐1 on SNARE complex formation (“SNARE‐templating”) and membrane fusion in vitro. Furthermore, priming but not docking of synaptic vesicles was disrupted in hippocampal munc18‐1‐null neurons expressing Munc18‐1Y473D. Synaptic transmission was temporarily restored by high‐frequency stimulation, as well as by a Munc18‐1 mutation that results in helix 12 extension, a critical conformational step in vesicle priming. On the other hand, expression of non‐phosphorylatable Munc18‐1 supported normal synaptic transmission. We propose that SFK‐dependent Munc18‐1 phosphorylation may constitute a potent, previously unknown mechanism to shut down synaptic transmission, via direct occlusion of a Synaptobrevin/VAMP2 binding groove and subsequent hindrance of conformational changes in domain 3a responsible for vesicle priming. This would strongly interfere with the essential post‐docking SNARE‐templating role of Munc18‐1, resulting in a largely abolished pool of releasable synaptic vesicles.
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Affiliation(s)
- Marieke Meijer
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA) VU University Medical Center, Amsterdam, The Netherlands
| | - Bernhard Dörr
- Heidelberg University Biochemistry Center (BZH), Heidelberg, Germany
| | - Hanna Ca Lammertse
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA) VU University Amsterdam, Amsterdam, The Netherlands
| | - Chrysanthi Blithikioti
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA) VU University Amsterdam, Amsterdam, The Netherlands
| | - Jan Rt van Weering
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA) VU University Medical Center, Amsterdam, The Netherlands
| | - Ruud Fg Toonen
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA) VU University Amsterdam, Amsterdam, The Netherlands
| | - Thomas H Söllner
- Heidelberg University Biochemistry Center (BZH), Heidelberg, Germany
| | - Matthijs Verhage
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA) VU University Medical Center, Amsterdam, The Netherlands .,Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA) VU University Amsterdam, Amsterdam, The Netherlands
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Mast N, Lin JB, Anderson KW, Bjorkhem I, Pikuleva IA. Transcriptional and post-translational changes in the brain of mice deficient in cholesterol removal mediated by cytochrome P450 46A1 (CYP46A1). PLoS One 2017; 12:e0187168. [PMID: 29073233 PMCID: PMC5658173 DOI: 10.1371/journal.pone.0187168] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 10/13/2017] [Indexed: 01/12/2023] Open
Abstract
Cytochrome P450 46A1 (CYP46A1) converts cholesterol to 24-hydroxycholesterol and thereby controls the major pathways of cholesterol removal from the brain. Cyp46a1-/- mice have a reduction in the rate of cholesterol biosynthesis in the brain and significant impairments to memory and learning. To gain insights into the mechanisms underlying Cyp46a1-/- phenotype, we used Cyp46a1-/- mice and quantified their brain sterol levels and the expression of the genes pertinent to cholesterol homeostasis. We also compared the Cyp46a1-/- and wild type brains for protein phosphorylation and ubiquitination. The data obtained enable the following inferences. First, there seems to be a compensatory upregulation in the Cyp46a1-/- brain of the pathways of cholesterol storage and CYP46A1-independent removal. Second, transcriptional regulation of the brain cholesterol biosynthesis via sterol regulatory element binding transcription factors is not significantly activated in the Cyp46a1-/- brain to explain a compensatory decrease in cholesterol biosynthesis. Third, some of the liver X receptor target genes (Abca1) are paradoxically upregulated in the Cyp46a1-/- brain, possibly due to a reduced activation of the small GTPases RAB8, CDC42, and RAC as a result of a reduced phosphorylation of RAB3IP and PAK1. Fourth, the phosphorylation of many other proteins (a total of 146) is altered in the Cyp46a1-/- brain, including microtubule associated and neurofilament proteins (the MAP and NEF families) along with proteins related to synaptic vesicles and synaptic neurotransmission (e.g., SLCs, SHANKs, and BSN). Fifth, the extent of protein ubiquitination is increased in the Cyp46a1-/- brain, and the affected proteins pertain to ubiquitination (UBE2N), cognition (STX1B and ATP1A2), cytoskeleton function (TUBA1A and YWHAZ), and energy production (ATP1A2 and ALDOA). The present study demonstrates the diverse potential effects of CYP46A1 deficiency on brain functions and identifies important proteins that could be affected by this deficiency.
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Affiliation(s)
- Natalia Mast
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Joseph B. Lin
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Kyle W. Anderson
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, United States of America
- Institute for Bioscience and Biotechnology Research, Rockville, Maryland, United States of America
| | - Ingemar Bjorkhem
- Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska Institute, Huddinge, Sweden
| | - Irina A. Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
- * E-mail:
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Spatiotemporal profile of postsynaptic interactomes integrates components of complex brain disorders. Nat Neurosci 2017; 20:1150-1161. [PMID: 28671696 DOI: 10.1038/nn.4594] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 05/17/2017] [Indexed: 12/30/2022]
Abstract
The postsynaptic density (PSD) contains a collection of scaffold proteins used for assembling synaptic signaling complexes. However, it is not known how the core-scaffold machinery associates in protein-interaction networks or how proteins encoded by genes involved in complex brain disorders are distributed through spatiotemporal protein complexes. Here using immunopurification, proteomics and bioinformatics, we isolated 2,876 proteins across 41 in vivo interactomes and determined their protein domain composition, correlation to gene expression levels and developmental integration to the PSD. We defined clusters for enrichment of schizophrenia, autism spectrum disorders, developmental delay and intellectual disability risk factors at embryonic day 14 and adult PSD in mice. Mutations in highly connected nodes alter protein-protein interactions modulating macromolecular complexes enriched in disease risk candidates. These results were integrated into a software platform, Synaptic Protein/Pathways Resource (SyPPRes), enabling the prioritization of disease risk factors and their placement within synaptic protein interaction networks.
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Ganguly A, Han X, Das U, Wang L, Loi J, Sun J, Gitler D, Caillol G, Leterrier C, Yates JR, Roy S. Hsc70 chaperone activity is required for the cytosolic slow axonal transport of synapsin. J Cell Biol 2017; 216:2059-2074. [PMID: 28559423 PMCID: PMC5496608 DOI: 10.1083/jcb.201604028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 08/22/2016] [Accepted: 04/17/2017] [Indexed: 12/19/2022] Open
Abstract
Using proteomics, live microscopy, and superresolution microscopy, Ganguly et al. offer insight into the molecular composition of cytosolic cargo complexes conveyed in slow axonal transport, identifying the heat shock protein Hsc70 as a major regulator of this transport. Soluble cytosolic proteins vital to axonal and presynaptic function are synthesized in the neuronal soma and conveyed via slow axonal transport. Our previous studies suggest that the overall slow transport of synapsin is mediated by dynamic assembly/disassembly of cargo complexes followed by short-range vectorial transit (the “dynamic recruitment” model). However, neither the composition of these complexes nor the mechanistic basis for the dynamic behavior is understood. In this study, we first examined putative cargo complexes associated with synapsin using coimmunoprecipitation and multidimensional protein identification technology mass spectrometry (MS). MS data indicate that synapsin is part of a multiprotein complex enriched in chaperones/cochaperones including Hsc70. Axonal synapsin–Hsc70 coclusters are also visualized by two-color superresolution microscopy. Inhibition of Hsc70 ATPase activity blocked the slow transport of synapsin, disrupted axonal synapsin organization, and attenuated Hsc70–synapsin associations, advocating a model where Hsc70 activity dynamically clusters cytosolic proteins into cargo complexes, allowing transport. Collectively, our study offers insight into the molecular organization of cytosolic transport complexes and identifies a novel regulator of slow transport.
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Affiliation(s)
- Archan Ganguly
- Department of Pathology, University of California, San Diego, La Jolla, CA
| | - Xuemei Han
- Department of Cell Biology, The Scripps Research Institute, La Jolla, CA
| | - Utpal Das
- Department of Pathology, University of California, San Diego, La Jolla, CA
| | - Lina Wang
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI
| | - Jonathan Loi
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI
| | - Jichao Sun
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI
| | - Daniel Gitler
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev and Zlotowski Center for Neuroscience, Beer-Sheva, Israel
| | - Ghislaine Caillol
- Aix Marseille Université, Centre National de la Recherche Scientifique, NICN UMR7259, Marseille, France
| | - Christophe Leterrier
- Aix Marseille Université, Centre National de la Recherche Scientifique, NICN UMR7259, Marseille, France
| | - John R Yates
- Department of Cell Biology, The Scripps Research Institute, La Jolla, CA
| | - Subhojit Roy
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI .,Department of Neuroscience, University of Wisconsin-Madison, Madison, WI
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Phosphorylation of Drebrin and Its Role in Neuritogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1006:49-60. [PMID: 28865014 DOI: 10.1007/978-4-431-56550-5_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Neuritogenesis is an early event in neuronal development in which newborn neurons first form growth cones, as a prerequisite for the formation of axons and dendrites. Growth cones emerge from segmented regions of the lamellipodium of embryonic neurons and grow away from the cell body leaving behind a neurite that will eventually polarise into an axon or dendrite. Growth cones also function to navigate precise routes through the embryo to locate an appropriate synaptic partner. Dynamic interactions between two components of the neuronal cytoskeleton, actin filaments and microtubules, are known to be essential for growth cone formation and hence neuritogenesis. The molecular mechanisms that coordinate interactions between actin filaments and dynamic microtubules during neuritogenesis are beginning to be understood. One candidate pathway coupling actin filaments to microtubules consists of the actin filament-binding protein drebrin and the microtubule-binding +TIP protein EB3. This pathway is regulated proximally by cyclin-dependent kinase 5 phosphorylation of drebrin but the upstream elements in the pathway have yet to be identified.
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Posada-Duque RA, Ramirez O, Härtel S, Inestrosa NC, Bodaleo F, González-Billault C, Kirkwood A, Cardona-Gómez GP. CDK5 downregulation enhances synaptic plasticity. Cell Mol Life Sci 2017; 74:153-172. [PMID: 27506619 PMCID: PMC11107552 DOI: 10.1007/s00018-016-2333-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 08/02/2016] [Accepted: 08/04/2016] [Indexed: 01/06/2023]
Abstract
CDK5 is a serine/threonine kinase that is involved in the normal function of the adult brain and plays a role in neurotransmission and synaptic plasticity. However, its over-regulation has been associated with Tau hyperphosphorylation and cognitive deficits. Our previous studies have demonstrated that CDK5 targeting using shRNA-miR provides neuroprotection and prevents cognitive deficits. Dendritic spine morphogenesis and forms of long-term synaptic plasticity-such as long-term potentiation (LTP)-have been proposed as essential processes of neuroplasticity. However, whether CDK5 participates in these processes remains controversial and depends on the experimental model. Using wild-type mice that received injections of CDK5 shRNA-miR in CA1 showed an increased LTP and recovered the PPF in deficient LTP of APPswe/PS1Δ9 transgenic mice. On mature hippocampal neurons CDK5, shRNA-miR for 12 days induced increased dendritic protrusion morphogenesis, which was dependent on Rac activity. In addition, silencing of CDK5 increased BDNF expression, temporarily increased phosphorylation of CaMKII, ERK, and CREB; and facilitated calcium signaling in neurites. Together, our data suggest that CDK5 downregulation induces synaptic plasticity in mature neurons involving Ca2+ signaling and BDNF/CREB activation.
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Affiliation(s)
- Rafael Andrés Posada-Duque
- Cellular and Molecular Neurobiology Area, Group of Neuroscience of Antioquia, Faculty of Medicine, SIU, University of Antioquia, Calle 62 # 52-59, Torre 1, Piso 4, Laboratorio 412, Medellín, Colombia
| | - Omar Ramirez
- Laboratory for Scientific Image Analysis (SCIAN-Lab), Center for Medical Informatics and Telemedicine (CIMT), Biomedical Neuroscience Institute BNI, ICBM, Universidad de Chile, Santiago, Chile
| | - Steffen Härtel
- Laboratory for Scientific Image Analysis (SCIAN-Lab), Center for Medical Informatics and Telemedicine (CIMT), Biomedical Neuroscience Institute BNI, ICBM, Universidad de Chile, Santiago, Chile
| | - Nibaldo C Inestrosa
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Centro de Envejecimiento y Regeneración, Pontificia Universidad Católica de Chile, 8331150, Santiago, Chile
| | - Felipe Bodaleo
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago, Chile
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile
| | - Christian González-Billault
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago, Chile
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile
| | - Alfredo Kirkwood
- Solomon H. Snyder Department of Neuroscience, Zanvyl-Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, USA
| | - Gloria Patricia Cardona-Gómez
- Cellular and Molecular Neurobiology Area, Group of Neuroscience of Antioquia, Faculty of Medicine, SIU, University of Antioquia, Calle 62 # 52-59, Torre 1, Piso 4, Laboratorio 412, Medellín, Colombia.
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Tenreiro P, Rebelo S, Martins F, Santos M, Coelho ED, Almeida M, Alves de Matos AP, da Cruz E Silva OAB. Comparison of simple sucrose and percoll based methodologies for synaptosome enrichment. Anal Biochem 2016; 517:1-8. [PMID: 27771393 DOI: 10.1016/j.ab.2016.10.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 09/16/2016] [Accepted: 10/18/2016] [Indexed: 01/20/2023]
Abstract
Synaptosomes are isolated nerve terminals. They represent an extremely attractive in vitro model system to study synaptic physiology since they preserve morphological and functional characteristics of the synapse. As such they have been used to investigate synaptic dysfunctions associated with neuropathologies like Alzheimer's disease. In the present work two simple methodologies for isolating synaptosomal-enriched fractions were compared for the first time. The starting points of both protocols were rat cortical or hippocampal homogenized tissues that underwent several differential centrifugation steps followed by a final purification of synaptosomal-enriched fractions using either a Percoll gradient or a Sucrose gradient. Comparison of the fractions obtained was carried out, using both biochemical and electron microscopy approaches. In the biochemical analysis the protein levels of pre-synaptic, post-synaptic, nuclear and mitochondrial markers were evaluated. Additional characterization of the synaptosomal-enriched fractions was performed using transmission electron microscopy. In summary, the results indicate that under the conditions tested the Sucrose based protocol is more efficient for the isolation of synaptosomal-enriched fractions from both neuronal tissues, being particularly efficient for hippocampus that is a less abundant brain tissue. Further, the sucrose protocol apparently results in a higher yield of viable synaptosomes suitable for further assays, including structural and functional studies of synapses; making this an attractive procedure to study processes associated with neuropathologies.
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Affiliation(s)
- P Tenreiro
- Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal
| | - S Rebelo
- Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal.
| | - F Martins
- Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal
| | - M Santos
- Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal
| | - E D Coelho
- Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal
| | - M Almeida
- Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal
| | - A P Alves de Matos
- Centro de Estudos do Ambiente e do Mar, Faculdade de Ciências da Universidade de Lisboa, Portugal; Centro de Investigação Interdisciplinar Egas Moniz, Monte de Caparica, Lisboa, Portugal
| | - O A B da Cruz E Silva
- Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal
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43
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Paradoxical signaling regulates structural plasticity in dendritic spines. Proc Natl Acad Sci U S A 2016; 113:E5298-307. [PMID: 27551076 DOI: 10.1073/pnas.1610391113] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Transient spine enlargement (3- to 5-min timescale) is an important event associated with the structural plasticity of dendritic spines. Many of the molecular mechanisms associated with transient spine enlargement have been identified experimentally. Here, we use a systems biology approach to construct a mathematical model of biochemical signaling and actin-mediated transient spine expansion in response to calcium influx caused by NMDA receptor activation. We have identified that a key feature of this signaling network is the paradoxical signaling loop. Paradoxical components act bifunctionally in signaling networks, and their role is to control both the activation and the inhibition of a desired response function (protein activity or spine volume). Using ordinary differential equation (ODE)-based modeling, we show that the dynamics of different regulators of transient spine expansion, including calmodulin-dependent protein kinase II (CaMKII), RhoA, and Cdc42, and the spine volume can be described using paradoxical signaling loops. Our model is able to capture the experimentally observed dynamics of transient spine volume. Furthermore, we show that actin remodeling events provide a robustness to spine volume dynamics. We also generate experimentally testable predictions about the role of different components and parameters of the network on spine dynamics.
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44
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Li J, Wilkinson B, Clementel VA, Hou J, O'Dell TJ, Coba MP. Long-term potentiation modulates synaptic phosphorylation networks and reshapes the structure of the postsynaptic interactome. Sci Signal 2016; 9:rs8. [PMID: 27507650 DOI: 10.1126/scisignal.aaf6716] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The postsynaptic site of neurons is composed of more than 1500 proteins arranged in protein-protein interaction complexes, the composition of which is modulated by protein phosphorylation through the actions of complex signaling networks. Components of these networks function as key regulators of synaptic plasticity, in particular hippocampal long-term potentiation (LTP). The postsynaptic density (PSD) is a complex multicomponent structure that includes receptors, enzymes, scaffold proteins, and structural proteins. We triggered LTP in the mouse hippocampus CA1 region and then performed large-scale analyses to identify phosphorylation-mediated events in the PSD and changes in the protein-protein interactome of the PSD that were associated with LTP induction. Our data indicated LTP-induced reorganization of the PSD. The dynamic reorganization of the PSD links glutamate receptor signaling to kinases (writers) and phosphatases (erasers), as well as the target proteins that are modulated by protein phosphorylation and the proteins that recognize the phosphorylation status of their binding partners (readers). Protein phosphorylation and protein interaction networks converged at highly connected nodes within the PSD network. Furthermore, the LTP-regulated phosphoproteins, which included the scaffold proteins Shank3, Syngap1, Dlgap1, and Dlg4, represented the "PSD risk" for schizophrenia and autism spectrum disorder, such that without these proteins in the analysis, the association with the PSD and these two psychiatric diseases was not present. These data are a rich resource for future studies of LTP and suggest that the PSD holds the keys to understanding the molecular events that contribute to complex neurological disorders that affect synaptic plasticity.
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Affiliation(s)
- Jing Li
- Zilkha Neurogenetic Institute, Los Angeles, CA, 90089, USA
| | | | | | - Junjie Hou
- National Laboratory of Bio-Macromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Thomas J O'Dell
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90024, USA
| | - Marcelo P Coba
- Zilkha Neurogenetic Institute, Los Angeles, CA, 90089, USA. Department of Psychiatry and Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
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45
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Patel P, Prescott GR, Burgoyne RD, Lian LY, Morgan A. Phosphorylation of Cysteine String Protein Triggers a Major Conformational Switch. Structure 2016; 24:1380-1386. [PMID: 27452402 PMCID: PMC4975591 DOI: 10.1016/j.str.2016.06.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 05/17/2016] [Accepted: 06/02/2016] [Indexed: 12/11/2022]
Abstract
Cysteine string protein (CSP) is a member of the DnaJ/Hsp40 chaperone family that localizes to neuronal synaptic vesicles. Impaired CSP function leads to neurodegeneration in humans and model organisms as a result of misfolding of client proteins involved in neurotransmission. Mammalian CSP is phosphorylated in vivo on Ser10, and this modulates its protein interactions and effects on neurotransmitter release. However, there are no data on the structural consequences of CSP phosphorylation to explain these functional effects. We show that Ser10 phosphorylation causes an order-to-disorder transition that disrupts CSP's extreme N-terminal α helix. This triggers the concomitant formation of a hairpin loop stabilized by ionic interactions between phosphoSer10 and the highly conserved J-domain residue, Lys58. These phosphorylation-induced effects result in significant changes to CSP conformation and surface charge distribution. The phospho-switch revealed here provides structural insight into how Ser10 phosphorylation modulates CSP function and also has potential implications for other DnaJ phosphoproteins. First structure of a phosphorylated DnaJ/Hsp40 protein Phosphorylation destabilizes CSP's N-terminal α helix Newly disordered, phosphorylated N-terminal loop binds to the J domain Phosphorylation causes significant changes to CSP conformation and surface charge
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Affiliation(s)
- Pryank Patel
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool L69 3BX, UK; NMR Centre for Structural Biology, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 3BX, UK; Department of Biological and Environmental Sciences, University of Hertfordshire, Hatfield AL10 9AB, UK
| | - Gerald R Prescott
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool L69 3BX, UK
| | - Robert D Burgoyne
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool L69 3BX, UK
| | - Lu-Yun Lian
- NMR Centre for Structural Biology, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 3BX, UK.
| | - Alan Morgan
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool L69 3BX, UK.
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46
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Microtubule-associated protein 1B (MAP1B)-deficient neurons show structural presynaptic deficiencies in vitro and altered presynaptic physiology. Sci Rep 2016; 6:30069. [PMID: 27425640 PMCID: PMC4948024 DOI: 10.1038/srep30069] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 06/28/2016] [Indexed: 11/20/2022] Open
Abstract
Microtubule-associated protein 1B (MAP1B) is expressed predominantly during the early stages of development of the nervous system, where it regulates processes such as axonal guidance and elongation. Nevertheless, MAP1B expression in the brain persists in adult stages, where it participates in the regulation of the structure and physiology of dendritic spines in glutamatergic synapses. Moreover, MAP1B expression is also found in presynaptic synaptosomal preparations. In this work, we describe a presynaptic phenotype in mature neurons derived from MAP1B knockout (MAP1B KO) mice. Mature neurons express MAP1B, and its deficiency does not alter the expression levels of a subgroup of other synaptic proteins. MAP1B KO neurons display a decrease in the density of presynaptic and postsynaptic terminals, which involves a reduction in the density of synaptic contacts, and an increased proportion of orphan presynaptic terminals. Accordingly, MAP1B KO neurons present altered synaptic vesicle fusion events, as shown by FM4-64 release assay, and a decrease in the density of both synaptic vesicles and dense core vesicles at presynaptic terminals. Finally, an increased proportion of excitatory immature symmetrical synaptic contacts in MAP1B KO neurons was detected. Altogether these results suggest a novel role for MAP1B in presynaptic structure and physiology regulation in vitro.
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47
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Dieterich DC, Kreutz MR. Proteomics of the Synapse--A Quantitative Approach to Neuronal Plasticity. Mol Cell Proteomics 2016; 15:368-81. [PMID: 26307175 PMCID: PMC4739661 DOI: 10.1074/mcp.r115.051482] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 07/29/2015] [Indexed: 11/06/2022] Open
Abstract
The advances in mass spectrometry based proteomics in the past 15 years have contributed to a deeper appreciation of protein networks and the composition of functional synaptic protein complexes. However, research on protein dynamics underlying core mechanisms of synaptic plasticity in brain lag far behind. In this review, we provide a synopsis on proteomic research addressing various aspects of synaptic function. We discuss the major topics in the study of protein dynamics of the chemical synapse and the limitations of current methodology. We highlight recent developments and the future importance of multidimensional proteomics and metabolic labeling. Finally, emphasis is given on the conceptual framework of modern proteomics and its current shortcomings in the quest to gain a deeper understanding of synaptic plasticity.
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Affiliation(s)
- Daniela C Dieterich
- From the ‡Institute for Pharmacology and Toxicology, Otto-von-Guericke University Magdeburg, Germany; Research Group Neuralomics, Leibniz Institute for Neurobiology Magdeburg, Germany; ¶Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany.
| | - Michael R Kreutz
- §RG Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany; ¶Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany.
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48
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Wang Q, Amato SP, Rubitski DM, Hayward MM, Kormos BL, Verhoest PR, Xu L, Brandon NJ, Ehlers MD. Identification of Phosphorylation Consensus Sequences and Endogenous Neuronal Substrates of the Psychiatric Risk Kinase TNIK. J Pharmacol Exp Ther 2015; 356:410-23. [PMID: 26645429 DOI: 10.1124/jpet.115.229880] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 12/01/2015] [Indexed: 12/28/2022] Open
Abstract
Traf2- and Nck-interacting kinase (TNIK) is a serine/threonine kinase highly expressed in the brain and enriched in the postsynaptic density of glutamatergic synapses in the mammalian brain. Accumulating genetic evidence and functional data have implicated TNIK as a risk factor for psychiatric disorders. However, the endogenous substrates of TNIK in neurons are unknown. Here, we describe a novel selective small molecule inhibitor of the TNIK kinase family. Using this inhibitor, we report the identification of endogenous neuronal TNIK substrates by immunoprecipitation with a phosphomotif antibody followed by mass spectrometry. Phosphorylation consensus sequences were defined by phosphopeptide sequence analysis. Among the identified substrates were members of the delta-catenin family including p120-catenin, δ-catenin, and armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF), each of which is linked to psychiatric or neurologic disorders. Using p120-catenin as a representative substrate, we show TNIK-induced p120-catenin phosphorylation in cells requires intact kinase activity and phosphorylation of TNIK at T181 and T187 in the activation loop. Addition of the small molecule TNIK inhibitor or knocking down TNIK by two shRNAs reduced endogenous p120-catenin phosphorylation in cells. Together, using a TNIK inhibitor and phosphomotif antibody, we identify endogenous substrates of TNIK in neurons, define consensus sequences for TNIK, and suggest signaling pathways by which TNIK influences synaptic development and function linked to psychiatric and neurologic disorders.
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Affiliation(s)
- Qi Wang
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - Stephen P Amato
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - David M Rubitski
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - Matthew M Hayward
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - Bethany L Kormos
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - Patrick R Verhoest
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - Lan Xu
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - Nicholas J Brandon
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
| | - Michael D Ehlers
- Neuroscience & Pain Research Unit, BioTherapeutics Research and Development, Pfizer Inc. Cambridge, Massachusetts (Q.W., S.P.A., D.M.R., N.J.B., M.D.E.); Center of Chemistry Innovation and Excellence, Pfizer Inc., Groton, Connecticut (M.M.H.); Neuroscience Medicinal Chemistry, Pfizer Inc., Cambridge, Massachusetts (B.L.K., P.R.V.);and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts (L.X.)
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49
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Ando H, Hirose M, Gainche L, Kawaai K, Bonneau B, Ijuin T, Itoh T, Takenawa T, Mikoshiba K. IRBIT Interacts with the Catalytic Core of Phosphatidylinositol Phosphate Kinase Type Iα and IIα through Conserved Catalytic Aspartate Residues. PLoS One 2015; 10:e0141569. [PMID: 26509711 PMCID: PMC4624786 DOI: 10.1371/journal.pone.0141569] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 10/10/2015] [Indexed: 11/18/2022] Open
Abstract
Phosphatidylinositol phosphate kinases (PIPKs) are lipid kinases that generate phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a critical lipid signaling molecule that regulates diverse cellular functions, including the activities of membrane channels and transporters. IRBIT (IP3R-binding protein released with inositol 1,4,5-trisphosphate) is a multifunctional protein that regulates diverse target proteins. Here, we report that IRBIT forms signaling complexes with members of the PIPK family. IRBIT bound to all PIPK isoforms in heterologous expression systems and specifically interacted with PIPK type Iα (PIPKIα) and type IIα (PIPKIIα) in mouse cerebellum. Site-directed mutagenesis revealed that two conserved catalytic aspartate residues of PIPKIα and PIPKIIα are involved in the interaction with IRBIT. Furthermore, phosphatidylinositol 4-phosphate, Mg2+, and/or ATP interfered with the interaction, suggesting that IRBIT interacts with catalytic cores of PIPKs. Mutations of phosphorylation sites in the serine-rich region of IRBIT affected the selectivity of its interaction with PIPKIα and PIPKIIα. The structural flexibility of the serine-rich region, located in the intrinsically disordered protein region, is assumed to underlie the mechanism of this interaction. Furthermore, in vitro binding experiments and immunocytochemistry suggest that IRBIT and PIPKIα interact with the Na+/HCO3− cotransporter NBCe1-B. These results suggest that IRBIT forms signaling complexes with PIPKIα and NBCe1-B, whose activity is regulated by PI(4,5)P2.
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Affiliation(s)
- Hideaki Ando
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
- * E-mail: (HA); (KM)
| | - Matsumi Hirose
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Laura Gainche
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Katsuhiro Kawaai
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Benjamin Bonneau
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Takeshi Ijuin
- Division of Biochemistry, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Toshiki Itoh
- Biosignal Research Center, Organization of Advanced Science and Technology, Kobe University, Kobe, Hyogo, Japan
| | - Tadaomi Takenawa
- Biosignal Research Center, Organization of Advanced Science and Technology, Kobe University, Kobe, Hyogo, Japan
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
- * E-mail: (HA); (KM)
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50
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Rasband MN. Glial Contributions to Neural Function and Disease. Mol Cell Proteomics 2015; 15:355-61. [PMID: 26342039 DOI: 10.1074/mcp.r115.053744] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Indexed: 12/31/2022] Open
Abstract
The nervous system consists of neurons and glial cells. Neurons generate and propagate electrical and chemical signals, whereas glia function mainly to modulate neuron function and signaling. Just as there are many different kinds of neurons with different roles, there are also many types of glia that perform diverse functions. For example, glia make myelin; modulate synapse formation, function, and elimination; regulate blood flow and metabolism; and maintain ionic and water homeostasis to name only a few. Although proteomic approaches have been used extensively to understand neurons, the same cannot be said for glia. Importantly, like neurons, glial cells have unique protein compositions that reflect their diverse functions, and these compositions can change depending on activity or disease. Here, I discuss the major classes and functions of glial cells in the central and peripheral nervous systems. I describe proteomic approaches that have been used to investigate glial cell function and composition and the experimental limitations faced by investigators working with glia.
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Affiliation(s)
- Matthew N Rasband
- From the Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030
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