1
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Pullara F, Forsmann MC, General IJ, Ayoob JC, Furbee E, Castro SL, Hu X, Greenamyre JT, Di Maio R. NADPH oxidase 2 activity disrupts Calmodulin/CaMKIIα complex via redox modifications of CaMKIIα-contained Cys30 and Cys289: Implications in Parkinson's disease. Redox Biol 2024; 75:103254. [PMID: 38968922 PMCID: PMC11278932 DOI: 10.1016/j.redox.2024.103254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 06/12/2024] [Accepted: 06/22/2024] [Indexed: 07/07/2024] Open
Abstract
Ca2+/calmodulin-dependent protein kinase II α (CaMKIIα) signaling in the brain plays a critical role in regulating neuronal Ca2+ homeostasis. Its dysfunctional activity is associated with various neurological and neurodegenerative disorders, including Parkinson's disease (PD). Using computational modeling analysis, we predicted that, two essential cysteine residues contained in CaMKIIα, Cys30 and Cys289, may undergo redox modifications impacting the proper functioning of the CaMKIIα docking site for Ca2+/CaM, thus impeding the formation of the CaMKIIα:Ca2+/CaM complex, essential for a proper modulation of CaMKIIα kinase activity. Our subsequent in vitro investigations confirmed the computational predictions, specifically implicating Cys30 and Cys289 residues in impairing CaMKIIα:Ca2+/CaM interaction. We observed CaMKIIα:Ca2+/CaM complex disruption in dopamine (DA) nigrostriatal neurons of post-mortem Parkinson's disease (PD) patients' specimens, addressing the high relevance of this event in the disease. CaMKIIα:Ca2+/CaM complex disruption was also observed in both in vitro and in vivo rotenone models of PD, where this phenomenon was associated with CaMKIIα kinase hyperactivity. Moreover, we observed that, NADPH oxidase 2 (NOX2), a major enzymatic generator of superoxide anion (O2●-) and hydrogen peroxide (H2O2) in the brain with implications in PD pathogenesis, is responsible for CaMKIIα:Ca2+/CaM complex disruption associated to a stable Ca2+CAM-independent CaMKIIα kinase activity and intracellular Ca2+ accumulation. The present study highlights the importance of oxidative stress, in disturbing the delicate balance of CaMKIIα signaling in calcium dysregulation, offering novel insights into PD pathogenesis.
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Affiliation(s)
| | - Madison C Forsmann
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA; Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh, PA, 15213, USA
| | - Ignacio J General
- School of Science and Technology, Universidad Nacional de San Martin, San Martín, 1650, Buenos Aires, Argentina
| | - Joseph C Ayoob
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Emily Furbee
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Sandra L Castro
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA; Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh, PA, 15213, USA
| | - Xiaoping Hu
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA; Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh, PA, 15213, USA
| | - J Timothy Greenamyre
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA; Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh, PA, 15213, USA
| | - Roberto Di Maio
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, 15213, USA; Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh, PA, 15213, USA.
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2
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Brown CN, Bayer KU. Studying CaMKII: Tools and standards. Cell Rep 2024; 43:113982. [PMID: 38517893 PMCID: PMC11088445 DOI: 10.1016/j.celrep.2024.113982] [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: 01/09/2024] [Revised: 02/19/2024] [Accepted: 03/06/2024] [Indexed: 03/24/2024] Open
Abstract
The Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) is a ubiquitous mediator of cellular Ca2+ signals with both enzymatic and structural functions. Here, we briefly introduce the complex regulation of CaMKII and then provide a comprehensive overview of the expanding toolbox to study CaMKII. Beyond a variety of distinct mutants, these tools now include optical methods for measurement and manipulation, with the latter including light-induced inhibition, stimulation, and sequestration. Perhaps most importantly, there are now three mechanistically distinct classes of specific CaMKII inhibitors, and their combined use enables the interrogation of CaMKII functions in a manner that is powerful and sophisticated yet also accessible. This review aims to provide guidelines for the interpretation of the results obtained with these tools, with careful consideration of their direct and indirect effects.
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Affiliation(s)
- Carolyn Nicole Brown
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Karl Ulrich Bayer
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
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3
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Xu J, Liang S, Wang Q, Zheng Q, Wang M, Qian J, Yu T, Lou S, Luo W, Zhou H, Liang G. JOSD2 mediates isoprenaline-induced heart failure by deubiquitinating CaMKIIδ in cardiomyocytes. Cell Mol Life Sci 2024; 81:18. [PMID: 38195959 PMCID: PMC11072575 DOI: 10.1007/s00018-023-05037-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 10/01/2023] [Accepted: 10/03/2023] [Indexed: 01/11/2024]
Abstract
Prolonged stimulation of β-adrenergic receptor (β-AR) can lead to sympathetic overactivity that causes pathologic cardiac hypertrophy and fibrosis, ultimately resulting in heart failure. Recent studies suggest that abnormal protein ubiquitylation may contribute to the pathogenesis of cardiac hypertrophy and remodeling. In this study, we demonstrated that deficiency of a deubiquitinase, Josephin domain-containing protein 2 (JOSD2), ameliorated isoprenaline (ISO)- and myocardial infarction (MI)-induced cardiac hypertrophy, fibrosis, and dysfunction both in vitro and in vivo. Conversely, JOSD2 overexpression aggravated ISO-induced cardiac pathology. Through comprehensive mass spectrometry analysis, we identified that JOSD2 interacts with Calcium-calmodulin-dependent protein kinase II (CaMKIIδ). JOSD2 directly hydrolyzes the K63-linked polyubiquitin chains on CaMKIIδ, thereby increasing the phosphorylation of CaMKIIδ and resulting in calcium mishandling, hypertrophy, and fibrosis in cardiomyocytes. In vivo experiments showed that the cardiac remodeling induced by JOSD2 overexpression could be reversed by the CaMKIIδ inhibitor KN-93. In conclusion, our study highlights the role of JOSD2 in mediating ISO-induced cardiac remodeling through the regulation of CaMKIIδ ubiquitination, and suggests its potential as a therapeutic target for combating the disease. Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary. All have been checked.
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Affiliation(s)
- Jiachen Xu
- Department of Cardiology, Medical Research Center, the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Shiqi Liang
- Department of Cardiology, Medical Research Center, the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Qinyan Wang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Qingsong Zheng
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Mengyang Wang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
- Department of Pharmacology, College of Pharmacy, Beihua University, Jilin, 132013, Jilin, China
| | - Jinfu Qian
- Department of Cardiology, Medical Research Center, the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Tianxiang Yu
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Shuaijie Lou
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China
| | - Wu Luo
- Department of Cardiology, Medical Research Center, the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.
| | - Hao Zhou
- Department of Cardiology, Medical Research Center, the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.
| | - Guang Liang
- Department of Cardiology, Medical Research Center, the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.
- School of Pharmaceutical Sciences, Hangzhou Medical College, Hangzhou, 311399, Zhejiang, China.
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4
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Abd Alla J, Langer A, Wolf S, Fu X, Rageh MA, Quitterer U. BBLN triggers CAMK2D pathology in mice under cardiac pressure overload and potentially in unrepaired hearts with tetralogy of Fallot. NATURE CARDIOVASCULAR RESEARCH 2023; 2:1044-1059. [PMID: 38666071 PMCID: PMC11041739 DOI: 10.1038/s44161-023-00351-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 09/21/2023] [Indexed: 04/28/2024]
Abstract
Tetralogy of Fallot (TOF) is one of the most prevalent congenital heart defects, with adverse cardiac remodeling and long-term cardiac complications. Here, searching for pathomechanisms, we find upregulated bublin coiled-coil protein (BBLN) in heart specimens of TOF patients with cyanosis, which positively correlates with cardiac remodeling pathways. Human BBLN, a protein with largely unknown function, promoted heart failure features, with increased mortality when overexpressed in mice, in a protein dosage-dependent manner. BBLN enhanced cardiac inflammation, fibrosis and necroptosis by calcium/calmodulin-dependent protein kinase II delta (CAMK2D) activation, whereas a BBLN mutant with impaired CAMK2D binding was inert. Downregulation of CAMK2D by an interfering RNA retarded BBLN-induced symptoms of heart failure. Endogenous BBLN was induced by hypoxia as a major TOF feature in human patients and by chronic pressure overload in mice, and its downregulation decreased CAMK2D hyperactivity, necroptosis and cardiovascular dysfunction. Thus, BBLN promotes CAMK2D-induced pathways to pathological cardiac remodeling, which are triggered by hypoxia in TOF.
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Affiliation(s)
- Joshua Abd Alla
- Molecular Pharmacology, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Andreas Langer
- Molecular Pharmacology, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Stefan Wolf
- Molecular Pharmacology, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Xuebin Fu
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL USA
- Department of Cardiovascular–Thoracic Surgery, Ann & Robert H. Lurie Children’s Hospital, Chicago, IL USA
| | - Mohamed Abdelfattah Rageh
- Ain Shams University Hospitals, Cairo, Egypt
- Present Address: Dalhousie University of Canada, Halifax, Nova Scotia Canada
| | - Ursula Quitterer
- Molecular Pharmacology, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
- Department of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
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5
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Tullis JE, Larsen ME, Rumian NL, Freund RK, Boxer EE, Brown CN, Coultrap SJ, Schulman H, Aoto J, Dell'Acqua ML, Bayer KU. LTP induction by structural rather than enzymatic functions of CaMKII. Nature 2023; 621:146-153. [PMID: 37648853 PMCID: PMC10482691 DOI: 10.1038/s41586-023-06465-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 07/20/2023] [Indexed: 09/01/2023]
Abstract
Learning and memory are thought to require hippocampal long-term potentiation (LTP), and one of the few central dogmas of molecular neuroscience that has stood undisputed for more than three decades is that LTP induction requires enzymatic activity of the Ca2+/calmodulin-dependent protein kinase II (CaMKII)1-3. However, as we delineate here, the experimental evidence is surprisingly far from conclusive. All previous interventions inhibiting enzymatic CaMKII activity and LTP4-8 also interfere with structural CaMKII roles, in particular binding to the NMDA-type glutamate receptor subunit GluN2B9-14. Thus, we here characterized and utilized complementary sets of new opto-/pharmaco-genetic tools to distinguish between enzymatic and structural CaMKII functions. Several independent lines of evidence demonstrated LTP induction by a structural function of CaMKII rather than by its enzymatic activity. The sole contribution of kinase activity was autoregulation of this structural role via T286 autophosphorylation, which explains why this distinction has been elusive for decades. Directly initiating the structural function in a manner that circumvented this T286 role was sufficient to elicit robust LTP, even when enzymatic CaMKII activity was blocked.
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Affiliation(s)
- Jonathan E Tullis
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Matthew E Larsen
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Nicole L Rumian
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Ronald K Freund
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Emma E Boxer
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Carolyn Nicole Brown
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Steven J Coultrap
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Howard Schulman
- Department of Neurobiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Jason Aoto
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Mark L Dell'Acqua
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - K Ulrich Bayer
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
- Program in Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
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6
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Tone D, Ode KL, Zhang Q, Fujishima H, Yamada RG, Nagashima Y, Matsumoto K, Wen Z, Yoshida SY, Mitani TT, Arisato Y, Ohno RI, Ukai-Tadenuma M, Yoshida Garçon J, Kaneko M, Shi S, Ukai H, Miyamichi K, Okada T, Sumiyama K, Kiyonari H, Ueda HR. Distinct phosphorylation states of mammalian CaMKIIβ control the induction and maintenance of sleep. PLoS Biol 2022; 20:e3001813. [PMID: 36194579 PMCID: PMC9531794 DOI: 10.1371/journal.pbio.3001813] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022] Open
Abstract
The reduced sleep duration previously observed in Camk2b knockout mice revealed a role for Ca2+/calmodulin-dependent protein kinase II (CaMKII)β as a sleep-promoting kinase. However, the underlying mechanism by which CaMKIIβ supports sleep regulation is largely unknown. Here, we demonstrate that activation or inhibition of CaMKIIβ can increase or decrease sleep duration in mice by almost 2-fold, supporting the role of CaMKIIβ as a core sleep regulator in mammals. Importantly, we show that this sleep regulation depends on the kinase activity of CaMKIIβ. A CaMKIIβ mutant mimicking the constitutive-active (auto)phosphorylation state promotes the transition from awake state to sleep state, while mutants mimicking subsequent multisite (auto)phosphorylation states suppress the transition from sleep state to awake state. These results suggest that the phosphorylation states of CaMKIIβ differently control sleep induction and maintenance processes, leading us to propose a "phosphorylation hypothesis of sleep" for the molecular control of sleep in mammals.
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Affiliation(s)
- Daisuke Tone
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Koji L. Ode
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Qianhui Zhang
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Hiroshi Fujishima
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
| | - Rikuhiro G. Yamada
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
| | - Yoshiki Nagashima
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- Thermo Fisher Scientific K.K., Yokohama, Kanagawa, Japan
| | - Katsuhiko Matsumoto
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
| | - Zhiqing Wen
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Shota Y. Yoshida
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
- Graduate school of Medicine, Osaka University, Suita, Osaka, Japan
| | - Tomoki T. Mitani
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
- Graduate school of Medicine, Osaka University, Suita, Osaka, Japan
| | - Yuki Arisato
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Rei-ichiro Ohno
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Maki Ukai-Tadenuma
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
| | - Junko Yoshida Garçon
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
| | - Mari Kaneko
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Chuo-ku, Kobe, Hyogo, Japan
| | - Shoi Shi
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Hideki Ukai
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
| | - Kazunari Miyamichi
- Laboratory for Comparative Connections, RIKEN Center for Biosystems Dynamics Research, Chuo-ku, Kobe, Hyogo, Japan
| | - Takashi Okada
- Division of Molecular and Medical Genetics, Center for Gene and Cell Therapy, The Institute of Medical Science, the University of Tokyo, Minato-city, Tokyo, Japan
| | - Kenta Sumiyama
- Laboratory for Mouse Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
| | - Hiroshi Kiyonari
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Chuo-ku, Kobe, Hyogo, Japan
| | - Hiroki R. Ueda
- Laboratory for Synthetic Biology, RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan
- Department of Systems Pharmacology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- * E-mail:
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7
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Buonarati OR, Miller AP, Coultrap SJ, Bayer KU, Reichow SL. Conserved and divergent features of neuronal CaMKII holoenzyme structure, function, and high-order assembly. Cell Rep 2021; 37:110168. [PMID: 34965414 PMCID: PMC8985225 DOI: 10.1016/j.celrep.2021.110168] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 08/30/2021] [Accepted: 12/03/2021] [Indexed: 11/23/2022] Open
Abstract
Neuronal CaMKII holoenzymes (α and β isoforms) enable molecular signal computation underlying learning and memory but also mediate excitotoxic neuronal death. Here, we provide a comparative analysis of these signaling devices, using single-particle electron microscopy (EM) in combination with biochemical and live-cell imaging studies. In the basal state, both isoforms assemble mainly as 12-mers (but also 14-mers and even 16-mers for the β isoform). CaMKIIα and β isoforms adopt an ensemble of extended activatable states (with average radius of 12.6 versus 16.8 nm, respectively), characterized by multiple transient intra- and inter-holoenzyme interactions associated with distinct functional properties. The extended state of CaMKIIβ allows direct resolution of intra-holoenzyme kinase domain dimers. These dimers could enable cooperative activation by calmodulin, which is observed for both isoforms. High-order CaMKII clustering mediated by inter-holoenzyme kinase domain dimerization is reduced for the β isoform for both basal and excitotoxicity-induced clusters, both in vitro and in neurons. The CaMKII holoenzyme enables neuronal signal computation. In a comparative structure-function analysis of the neuronal α and β isoforms, Buonarati et al. find evidence for kinase domain dimers within the holoenzyme that enable a cooperative activation mechanism in both isoforms and inter-holoenzyme interactions that enable high-order aggregate formation under ischemic conditions.
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Affiliation(s)
- Olivia R Buonarati
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Adam P Miller
- Department of Chemistry, Portland State University, Portland, OR 97201, USA
| | - Steven J Coultrap
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - K Ulrich Bayer
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
| | - Steve L Reichow
- Department of Chemistry, Portland State University, Portland, OR 97201, USA.
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8
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Cook SG, Buonarati OR, Coultrap SJ, Bayer KU. CaMKII holoenzyme mechanisms that govern the LTP versus LTD decision. SCIENCE ADVANCES 2021; 7:7/16/eabe2300. [PMID: 33853773 PMCID: PMC8046365 DOI: 10.1126/sciadv.abe2300] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 02/24/2021] [Indexed: 05/30/2023]
Abstract
Higher brain functions are thought to require synaptic frequency decoding that can lead to long-term potentiation (LTP) or depression (LTD). We show that the LTP versus LTD decision is determined by complex cross-regulation of T286 and T305/306 autophosphorylation within the 12meric CaMKII holoenzyme, which enabled molecular computation of stimulus frequency, amplitude, and duration. Both LTP and LTD require T286 phosphorylation, but T305/306 phosphorylation selectively promoted LTD. In response to excitatory LTP versus LTD stimuli, the differential T305/306 phosphorylation directed CaMKII movement to either excitatory or inhibitory synapses, thereby coordinating plasticity at both synapse types. Fast T305/306 phosphorylation required prior T286 phosphorylation and then curbed CaMKII activity by two mechanisms: (i) a cis-subunit reaction reduced both Ca2+ stimulation and autonomous activity and (ii) a trans-subunit reaction enabled complete activity shutdown and feed-forward inhibition of further T286 phosphorylation. These are fundamental additions to the long-studied CaMKII regulation and function in neuronal plasticity.
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Affiliation(s)
- Sarah G Cook
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Olivia R Buonarati
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Steven J Coultrap
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - K Ulrich Bayer
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
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9
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Asciutto EK, Pantano S, General IJ. Physical interactions driving the activation/inhibition of calcium/calmodulin dependent protein kinase II. J Mol Graph Model 2021; 105:107875. [PMID: 33711790 DOI: 10.1016/j.jmgm.2021.107875] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 01/29/2021] [Accepted: 02/18/2021] [Indexed: 12/15/2022]
Abstract
CaMKII is a protein kinase whose function is regulated by the binding of the Calcium/Calmodulin complex (Ca2+/CaM). It is a major player in the Long Term Potentiation process where it acts as a molecular switch, oscillating between inhibited and active conformations. The mechanism for the switching is thought to be initiated by Ca2+/CaM binding, which allows the trans-phosphorylation of a subunit of CaMKII by a neighboring kinase, leading to the active state of the system. A combination of all-atom and coarse-grained MD simulations with free energy calculations, led us to reveal an interplay of electrostatic forces exerted by Ca2+/CaM on CaMKII, which initiate the activation process. The highly electrically charged Ca2+/CaM neutralizes basic regions in the linker domain of CaMKII, facilitating its opening and consequent activation. The emerging picture of CaMKII's behavior highlights the preponderance of electrostatic interactions, which are modulated by the presence of Ca2+/CaM and the phosphorylation of key sites.
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Affiliation(s)
- Eliana K Asciutto
- School of Science and Technology, Universidad Nacional de San Martin, ICIFI and CONICET, 25 de Mayo y Francia, San Martín, 1650, Buenos Aires, Argentina
| | - Sergio Pantano
- Biomolecular Simulations Group, Institut Pasteur de Montevideo, Mataojo 2020, CP 11400, Montevideo, Uruguay
| | - Ignacio J General
- School of Science and Technology, Universidad Nacional de San Martin, ICIFI and CONICET, 25 de Mayo y Francia, San Martín, 1650, Buenos Aires, Argentina.
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10
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Konstantinidis K, Bezzerides VJ, Lai L, Isbell HM, Wei AC, Wu Y, Viswanathan MC, Blum ID, Granger JM, Heims-Waldron D, Zhang D, Luczak ED, Murphy KR, Lu F, Gratz DH, Manta B, Wang Q, Wang Q, Kolodkin AL, Gladyshev VN, Hund TJ, Pu WT, Wu MN, Cammarato A, Bianchet MA, Shea MA, Levine RL, Anderson ME. MICAL1 constrains cardiac stress responses and protects against disease by oxidizing CaMKII. J Clin Invest 2021; 130:4663-4678. [PMID: 32749237 PMCID: PMC7456244 DOI: 10.1172/jci133181] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 05/29/2020] [Indexed: 01/22/2023] Open
Abstract
Oxidant stress can contribute to health and disease. Here we show that invertebrates and vertebrates share a common stereospecific redox pathway that protects against pathological responses to stress, at the cost of reduced physiological performance, by constraining Ca2+/calmodulin-dependent protein kinase II (CaMKII) activity. MICAL1, a methionine monooxygenase thought to exclusively target actin, and MSRB, a methionine reductase, control the stereospecific redox status of M308, a highly conserved residue in the calmodulin-binding (CaM-binding) domain of CaMKII. Oxidized or mutant M308 (M308V) decreased CaM binding and CaMKII activity, while absence of MICAL1 in mice caused cardiac arrhythmias and premature death due to CaMKII hyperactivation. Mimicking the effects of M308 oxidation decreased fight-or-flight responses in mice, strikingly impaired heart function in Drosophila melanogaster, and caused disease protection in human induced pluripotent stem cell-derived cardiomyocytes with catecholaminergic polymorphic ventricular tachycardia, a CaMKII-sensitive genetic arrhythmia syndrome. Our studies identify a stereospecific redox pathway that regulates cardiac physiological and pathological responses to stress across species.
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Affiliation(s)
- Klitos Konstantinidis
- Division of Cardiology.,Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Lo Lai
- Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA
| | - Holly M Isbell
- Department of Biochemistry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - An-Chi Wei
- Department of Electrical Engineering, Graduate Institute of Biomedical and Bioinformatics, National Taiwan University, Taipei City, Taiwan
| | - Yuejin Wu
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Meera C Viswanathan
- Division of Cardiology.,Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Ian D Blum
- Department of Neurology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jonathan M Granger
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Donghui Zhang
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, USA.,State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Science, Hubei University, Wuhan, China
| | - Elizabeth D Luczak
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Kevin R Murphy
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Fujian Lu
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Daniel H Gratz
- Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.,Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Bruno Manta
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Qiang Wang
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qinchuan Wang
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Alex L Kolodkin
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, Maryland, USA
| | - Vadim N Gladyshev
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Thomas J Hund
- Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.,Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio, USA
| | - William T Pu
- Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, USA.,Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
| | - Mark N Wu
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.,Department of Neurology, Johns Hopkins University, Baltimore, Maryland, USA.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, Maryland, USA.,Department of Genetic Medicine
| | - Anthony Cammarato
- Division of Cardiology.,Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.,Department of Physiology, and
| | - Mario A Bianchet
- Department of Neurology, Johns Hopkins University, Baltimore, Maryland, USA.,Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, Maryland, USA
| | - Madeline A Shea
- Department of Biochemistry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Rodney L Levine
- Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA
| | - Mark E Anderson
- Division of Cardiology.,Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.,Department of Physiology, and
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11
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Karandur D, Bhattacharyya M, Xia Z, Lee YK, Muratcioglu S, McAffee D, McSpadden ED, Qiu B, Groves JT, Williams ER, Kuriyan J. Breakage of the oligomeric CaMKII hub by the regulatory segment of the kinase. eLife 2020; 9:57784. [PMID: 32902386 PMCID: PMC7538161 DOI: 10.7554/elife.57784] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 09/08/2020] [Indexed: 01/02/2023] Open
Abstract
Ca2+/calmodulin-dependent protein kinase II (CaMKII) is an oligomeric enzyme with crucial roles in neuronal signaling and cardiac function. Previously, we showed that activation of CaMKII triggers the exchange of subunits between holoenzymes, potentially increasing the spread of the active state (Stratton et al., 2014; Bhattacharyya et al., 2016). Using mass spectrometry, we show now that unphosphorylated and phosphorylated peptides derived from the CaMKII-α regulatory segment bind to the CaMKII-α hub and break it into smaller oligomers. Molecular dynamics simulations show that the regulatory segments dock spontaneously at the interface between hub subunits, trapping large fluctuations in hub structure. Single-molecule fluorescence intensity analysis of CaMKII-α expressed in mammalian cells shows that activation of CaMKII-α results in the destabilization of the holoenzyme. Our results suggest that release of the regulatory segment by activation and phosphorylation allows it to destabilize the hub, producing smaller assemblies that might reassemble to form new holoenzymes.
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Affiliation(s)
- Deepti Karandur
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
| | - Moitrayee Bhattacharyya
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
| | - Zijie Xia
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Young Kwang Lee
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Serena Muratcioglu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
| | - Darren McAffee
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Ethan D McSpadden
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
| | - Baiyu Qiu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
| | - Jay T Groves
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Department of Chemistry, University of California, Berkeley, Berkeley, United States.,Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, United States
| | - Evan R Williams
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - John Kuriyan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States.,Department of Chemistry, University of California, Berkeley, Berkeley, United States.,Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, United States
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12
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Bhattacharyya M, Lee YK, Muratcioglu S, Qiu B, Nyayapati P, Schulman H, Groves JT, Kuriyan J. Flexible linkers in CaMKII control the balance between activating and inhibitory autophosphorylation. eLife 2020; 9:e53670. [PMID: 32149607 PMCID: PMC7141811 DOI: 10.7554/elife.53670] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/06/2020] [Indexed: 12/24/2022] Open
Abstract
The many variants of human Ca2+/calmodulin-dependent protein kinase II (CaMKII) differ in the lengths and sequences of disordered linkers connecting the kinase domains to the oligomeric hubs of the holoenzyme. CaMKII activity depends on the balance between activating and inhibitory autophosphorylation (on Thr 286 and Thr 305/306, respectively, in the human α isoform). Variation in the linkers could alter transphosphorylation rates within a holoenzyme and the balance of autophosphorylation outcomes. We show, using mammalian cell expression and a single-molecule assay, that the balance of autophosphorylation is flipped between CaMKII variants with longer and shorter linkers. For the principal isoforms in the brain, CaMKII-α, with a ~30 residue linker, readily acquires activating autophosphorylation, while CaMKII-β, with a ~200 residue linker, is biased towards inhibitory autophosphorylation. Our results show how the responsiveness of CaMKII holoenzymes to calcium signals can be tuned by varying the relative levels of isoforms with long and short linkers.
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Affiliation(s)
- Moitrayee Bhattacharyya
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
| | - Young Kwang Lee
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Department of Chemistry, University of California, BerkeleyBerkeleyUnited States
| | - Serena Muratcioglu
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
| | - Baiyu Qiu
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
| | - Priya Nyayapati
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
| | - Howard Schulman
- Panorama Institute of Molecular MedicineSunnyvaleUnited States
| | - Jay T Groves
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Department of Chemistry, University of California, BerkeleyBerkeleyUnited States
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, BerkeleyBerkeleyUnited States
| | - John Kuriyan
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- California Institute for Quantitative Biosciences (QB3), University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California, BerkeleyBerkeleyUnited States
- Department of Chemistry, University of California, BerkeleyBerkeleyUnited States
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, BerkeleyBerkeleyUnited States
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13
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Bayer KU, Schulman H. CaM Kinase: Still Inspiring at 40. Neuron 2019; 103:380-394. [PMID: 31394063 DOI: 10.1016/j.neuron.2019.05.033] [Citation(s) in RCA: 198] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 02/12/2019] [Accepted: 05/21/2019] [Indexed: 01/07/2023]
Abstract
The Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) was touted as a memory molecule, even before its involvement in long-term potentiation (LTP) was shown. The enzyme has not disappointed, with subsequent demonstrations of remarkable structural and regulatory properties. Its neuronal functions now extend to long-term depression (LTD), and last year saw the first direct evidence for memory storage by CaMKII. Although CaMKII may have taken the spotlight, it is a member of a large family of diverse and interesting CaM kinases. Our aim is to place CaMKII in context of the other CaM kinases and then review certain aspects of this kinase that are of current interest.
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Affiliation(s)
- K Ulrich Bayer
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
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14
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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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15
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Chang JY, Nakahata Y, Hayano Y, Yasuda R. Mechanisms of Ca 2+/calmodulin-dependent kinase II activation in single dendritic spines. Nat Commun 2019; 10:2784. [PMID: 31239443 PMCID: PMC6592955 DOI: 10.1038/s41467-019-10694-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 05/22/2019] [Indexed: 11/09/2022] Open
Abstract
CaMKIIα plays an essential role in decoding Ca2+ signaling in spines by acting as a leaky Ca2+ integrator with the time constant of several seconds. However, the mechanism by which CaMKIIα integrates Ca2+ signals remains elusive. Here, we imaged CaMKIIα-CaM association in single dendritic spines using a new FRET sensor and two-photon fluorescence lifetime imaging. In response to a glutamate uncaging pulse, CaMKIIα-CaM association increases in ~0.1 s and decays over ~3 s. During repetitive glutamate uncaging, which induces spine structural plasticity, CaMKIIα-CaM association did not show further increase but sustained at a constant level. Since CaMKIIα activity integrates Ca2+ signals over ~10 s under this condition, the integration of Ca2+ signal by CaMKIIα during spine structural plasticity is largely due to Ca2+/CaM-independent, autonomous activity. Based on these results, we propose a simple kinetic model of CaMKIIα activation in dendritic spines.
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Affiliation(s)
- Jui-Yun Chang
- Department of Biochemistry, Duke University, Durham, NC, 27707, USA.,Neuronal Signal Transduction Group, Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
| | - Yoshihisa Nakahata
- Neuronal Signal Transduction Group, Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
| | - Yuki Hayano
- Neuronal Signal Transduction Group, Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
| | - Ryohei Yasuda
- Neuronal Signal Transduction Group, Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA.
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16
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Yamashita M, Sueyoshi N, Yamada H, Katayama S, Senga Y, Takenaka Y, Ishida A, Kameshita I, Shigeri Y. Characterization of CoPK02, a Ca 2+/calmodulin-dependent protein kinase in mushroom Coprinopsis cinerea. Biosci Biotechnol Biochem 2018; 82:1335-1343. [PMID: 29673297 DOI: 10.1080/09168451.2018.1462692] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We surveyed genome sequences from the basidiomycetous mushroom Coprinopsis cinerea and isolated a cDNA homologous to CMKA, a calmodulin-dependent protein kinase (CaMK) in Aspergillus nidulans. We designated this sequence, encoding 580 amino acids with a molecular weight of 63,987, as CoPK02. CoPK02 possessed twelve subdomains specific to protein kinases and exhibited 43, 35, 40% identity with rat CaMKI, CaMKII, CaMKIV, respectively, and 40% identity with CoPK12, one of the CaMK orthologs in C. cinerea. CoPK02 showed significant autophosphorylation activity and phosphorylated exogenous proteins in the presence of Ca2+/CaM. By the CaM-overlay assay we confirmed that the C-terminal sequence (Trp346-Arg358) was the calmodulin-binding site, and that the binding of Ca2+/CaM to CoPK02 was reduced by the autophosphorylation of CoPK02. Since CoPK02 evolved in a different clade from CoPK12, and showed different gene expression compared to that of CoPK32, which is homologous to mitogen-activated protein kinase-activated protein kinase, CoPK02 and CoPK12 might cooperatively regulate Ca2+-signaling in C. cinerea.
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Affiliation(s)
- Masashi Yamashita
- a Faculty of Agriculture, Department of Life Sciences , Kagawa University , Miki-Cho , Japan
| | - Noriyuki Sueyoshi
- a Faculty of Agriculture, Department of Life Sciences , Kagawa University , Miki-Cho , Japan
| | - Hiroki Yamada
- a Faculty of Agriculture, Department of Life Sciences , Kagawa University , Miki-Cho , Japan
| | - Syouichi Katayama
- a Faculty of Agriculture, Department of Life Sciences , Kagawa University , Miki-Cho , Japan
| | - Yukako Senga
- a Faculty of Agriculture, Department of Life Sciences , Kagawa University , Miki-Cho , Japan.,b Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba , Japan
| | - Yasuhiro Takenaka
- c Department of Physiology , Nippon Medical School , Bunkyo-ku, Japan
| | - Atsuhiko Ishida
- d Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences , Hiroshima University , Higashi-Hiroshima , Japan
| | - Isamu Kameshita
- a Faculty of Agriculture, Department of Life Sciences , Kagawa University , Miki-Cho , Japan
| | - Yasushi Shigeri
- e Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Takamatsu , Japan
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17
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Item-Place Encoding Through Hippocampal Long-Term Depression. HANDBOOK OF OBJECT NOVELTY RECOGNITION 2018. [DOI: 10.1016/b978-0-12-812012-5.00019-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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18
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Activation State-Dependent Substrate Gating in Ca 2+/Calmodulin-Dependent Protein Kinase II. Neural Plast 2017; 2017:9601046. [PMID: 29391954 PMCID: PMC5748111 DOI: 10.1155/2017/9601046] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Accepted: 10/23/2017] [Indexed: 12/15/2022] Open
Abstract
Calcium/calmodulin-dependent protein kinase II (CaMKII) is highly concentrated in the brain where its activation by the Ca2+ sensor CaM, multivalent structure, and complex autoregulatory features make it an ideal translator of Ca2+ signals created by different patterns of neuronal activity. We provide direct evidence that graded levels of kinase activity and extent of T287 (T286 α isoform) autophosphorylation drive changes in catalytic output and substrate selectivity. The catalytic domains of CaMKII phosphorylate purified PSDs much more effectively when tethered together in the holoenzyme versus individual subunits. Using multisubstrate SPOT arrays, high-affinity substrates are preferentially phosphorylated with limited subunit activity per holoenzyme, whereas multiple subunits or maximal subunit activation is required for intermediate- and low-affinity, weak substrates, respectively. Using a monomeric form of CaMKII to control T287 autophosphorylation, we demonstrate that increased Ca2+/CaM-dependent activity for all substrates tested, with the extent of weak, low-affinity substrate phosphorylation governed by the extent of T287 autophosphorylation. Our data suggest T287 autophosphorylation regulates substrate gating, an intrinsic property of the catalytic domain, which is amplified within the multivalent architecture of the CaMKII holoenzyme.
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19
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Woolfrey KM, O'Leary H, Goodell DJ, Robertson HR, Horne EA, Coultrap SJ, Dell'Acqua ML, Bayer KU. CaMKII regulates the depalmitoylation and synaptic removal of the scaffold protein AKAP79/150 to mediate structural long-term depression. J Biol Chem 2017; 293:1551-1567. [PMID: 29196604 DOI: 10.1074/jbc.m117.813808] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 11/21/2017] [Indexed: 11/06/2022] Open
Abstract
Both long-term potentiation (LTP) and depression (LTD) of excitatory synapse strength require the Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) and its autonomous activity generated by Thr-286 autophosphorylation. Additionally, LTP and LTD are correlated with dendritic spine enlargement and shrinkage that are accompanied by the synaptic accumulation or removal, respectively, of the AMPA-receptor regulatory scaffold protein A-kinase anchoring protein (AKAP) 79/150. We show here that the spine shrinkage associated with LTD indeed requires synaptic AKAP79/150 removal, which in turn requires CaMKII activity. In contrast to normal CaMKII substrates, the substrate sites within the AKAP79/150 N-terminal polybasic membrane-cytoskeletal targeting domain were phosphorylated more efficiently by autonomous compared with Ca2+/CaM-stimulated CaMKII activity. This unusual regulation was mediated by Ca2+/CaM binding to the substrate sites resulting in protection from phosphorylation in the presence of Ca2+/CaM, a mechanism that favors phosphorylation by prolonged, weak LTD stimuli versus brief, strong LTP stimuli. Phosphorylation by CaMKII inhibited AKAP79/150 association with F-actin; it also facilitated AKAP79/150 removal from spines but was not required for it. By contrast, LTD-induced spine removal of AKAP79/150 required its depalmitoylation on two Cys residues within the N-terminal targeting domain. Notably, such LTD-induced depalmitoylation was also blocked by CaMKII inhibition. These results provide a mechanism how CaMKII can indeed mediate not only LTP but also LTD through regulated substrate selection; however, in the case of AKAP79/150, indirect CaMKII effects on palmitoylation are more important than the effects of direct phosphorylation. Additionally, our results provide the first direct evidence for a function of the well-described AKAP79/150 trafficking in regulating LTD-induced spine shrinkage.
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Affiliation(s)
- Kevin M Woolfrey
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Heather O'Leary
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Dayton J Goodell
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Holly R Robertson
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Eric A Horne
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Steven J Coultrap
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Mark L Dell'Acqua
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - K Ulrich Bayer
- From the Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado 80045
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20
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Pullara F, Asciutto EK, General IJ. Mechanisms of Activation and Subunit Release in Ca2+/Calmodulin-Dependent Protein Kinase II. J Phys Chem B 2017; 121:10344-10352. [DOI: 10.1021/acs.jpcb.7b09214] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Filippo Pullara
- Department
of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Eliana K. Asciutto
- School
of Science and Technology, Universidad Nacional de San Martin, and CONICET, 25 de Mayo y Francia, San Martín, 1650 Buenos Aires, Argentina
| | - Ignacio J. General
- School
of Science and Technology, Universidad Nacional de San Martin, and CONICET, 25 de Mayo y Francia, San Martín, 1650 Buenos Aires, Argentina
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21
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Novel Roles for Peroxynitrite in Angiotensin II and CaMKII Signaling. Sci Rep 2016; 6:23416. [PMID: 27079272 PMCID: PMC4832198 DOI: 10.1038/srep23416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 03/07/2016] [Indexed: 12/28/2022] Open
Abstract
Ca2+/calmodulin-dependent protein kinase II (CaMKII) oxidation controls excitability and viability. While hydrogen peroxide (H2O2) affects Ca2+-activated CaMKII in vitro, Angiotensin II (Ang II)-induced CaMKIIδ signaling in cardiomyocytes is Ca2+ independent and requires NADPH oxidase-derived superoxide, but not its dismutation product H2O2. To better define the biological regulation of CaMKII activation and signaling by Ang II, we evaluated the potential for peroxynitrite (ONOO−) to mediate CaMKII activation and downstream Kv4.3 channel mRNA destabilization by Ang II. In vitro experiments show that ONOO− oxidizes and modestly activates pure CaMKII in the absence of Ca2+/CaM. Remarkably, this apokinase stimulation persists after mutating known oxidation targets (M281, M282, C290), suggesting a novel mechanism for increasing baseline Ca2+-independent CaMKII activity. The role of ONOO− in cardiac and neuronal responses to Ang II was then tested by scavenging ONOO− and preventing its formation by inhibiting nitric oxide synthase. Both treatments blocked Ang II effects on Kv4.3, tyrosine nitration and CaMKIIδ oxidation and activation. Together, these data show that ONOO− participates in Ang II-CaMKII signaling. The requirement for ONOO− in transducing Ang II signaling identifies ONOO−, which has been viewed as a reactive damaging byproduct of superoxide and nitric oxide, as a mediator of GPCR-CaMKII signaling.
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22
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Nguyen TA, Sarkar P, Veetil JV, Davis KA, Puhl HL, Vogel SS. Covert Changes in CaMKII Holoenzyme Structure Identified for Activation and Subsequent Interactions. Biophys J 2016; 108:2158-70. [PMID: 25954874 DOI: 10.1016/j.bpj.2015.03.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/18/2015] [Accepted: 03/10/2015] [Indexed: 11/29/2022] Open
Abstract
Between 8 to 14 calcium-calmodulin (Ca(2+)/CaM) dependent protein kinase-II (CaMKII) subunits form a complex that modulates synaptic activity. In living cells, the autoinhibited holoenzyme is organized as catalytic-domain pairs distributed around a central oligomerization-domain core. The functional significance of catalytic-domain pairing is not known. In a provocative model, catalytic-domain pairing was hypothesized to prevent ATP access to catalytic sites. If correct, kinase-activity would require catalytic-domain pair separation. Simultaneous homo-FRET and fluorescence correlation spectroscopy was used to detect structural changes correlated with kinase activation under physiological conditions. Saturating Ca(2+)/CaM triggered Threonine-286 autophosphorylation and a large increase in CaMKII holoenzyme hydrodynamic volume without any appreciable change in catalytic-domain pair proximity or subunit stoichiometry. An alternative hypothesis is that two appropriately positioned Threonine-286 interaction-sites (T-sites), each located on the catalytic-domain of a pair, are required for holoenzyme interactions with target proteins. Addition of a T-site ligand, in the presence of Ca(2+)/CaM, elicited a large decrease in catalytic-domain homo-FRET, which was blocked by mutating the T-site (I205K). Apparently catalytic-domain pairing is altered to allow T-site interactions.
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Affiliation(s)
- Tuan A Nguyen
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Pabak Sarkar
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Jithesh V Veetil
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Kaitlin A Davis
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Henry L Puhl
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland
| | - Steven S Vogel
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland.
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Mesubi OO, Anderson ME. Atrial remodelling in atrial fibrillation: CaMKII as a nodal proarrhythmic signal. Cardiovasc Res 2016; 109:542-57. [PMID: 26762270 DOI: 10.1093/cvr/cvw002] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/05/2016] [Indexed: 01/10/2023] Open
Abstract
CaMKII is a serine-threonine protein kinase that is abundant in myocardium. Emergent evidence suggests that CaMKII may play an important role in promoting atrial fibrillation (AF) by targeting a diverse array of proteins involved in membrane excitability, cell survival, calcium homeostasis, matrix remodelling, inflammation, and metabolism. Furthermore, CaMKII inhibition appears to protect against AF in animal models and correct proarrhythmic, defective intracellular Ca(2+) homeostasis in fibrillating human atrial cells. This review considers current concepts and evidence from animal and human studies on the role of CaMKII in AF.
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Affiliation(s)
- Olurotimi O Mesubi
- Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA Department of Medicine, The Johns Hopkins University School of Medicine, 1830 E. Monument Street, Suite 9026, Baltimore, MD 21287, USA
| | - Mark E Anderson
- Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA Department of Medicine, The Johns Hopkins University School of Medicine, 1830 E. Monument Street, Suite 9026, Baltimore, MD 21287, USA Department of Physiology and the Program in Cellular and Molecular Medicine, The Johns Hopkins School of Medicine, Baltimore, MD, USA
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24
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Wei Y, Han C, Wang Y, Wu B, Su T, Liu Y, He R. Ribosylation triggering Alzheimer's disease-like Tau hyperphosphorylation via activation of CaMKII. Aging Cell 2015; 14:754-63. [PMID: 26095350 PMCID: PMC4568963 DOI: 10.1111/acel.12355] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2015] [Indexed: 12/22/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is regarded as one of the serious risk factors for age-related cognitive impairment; however, a causal link between these two diseases has so far not been established. It was recently discovered that, apart from high D-glucose levels, T2DM patients also display abnormally high concentrations of uric D-ribose. Here, we show for the first time that the administration of D-ribose, the most active glycator among monosaccharides, produces high levels of advanced glycation end products (AGEs) and, importantly, triggers hyperphosphorylation of Tau in the brain of C57BL/6 mouse and neuroblastoma N2a cells. However, the administration of D-glucose showed no significant changes in Tau phosphorylation under the same experimental conditions. Crucially, suppression of AGE formation using an AGEs inhibitor (aminoguanidine) effectively prevents hyperphosphorylation of Tau protein. Further study shows AGEs resulted from ribosylation activate calcium-/calmodulin-dependent protein kinase type II (CaMKII), a key kinase responsible for Tau hyperphosphorylation. These data suggest that there is indeed a mechanistic link between ribosylation and Tau hyperphosphorylation. Targeting ribosylation by inhibiting AGE formation may be a promising therapeutic strategy to prevent Alzheimer’s disease-like Tau hyperphosphorylation and diabetic encephalopathies.
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Affiliation(s)
- Yan Wei
- State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101China
| | - Chanshuai Han
- State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101China
| | - Yujing Wang
- State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101China
- University of Chinese Academy of Sciences Beijing 100049China
| | - Beibei Wu
- State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101China
- University of Chinese Academy of Sciences Beijing 100049China
| | - Tao Su
- State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101China
| | - Ying Liu
- State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101China
- Alzheimer's Disease Center Beijing Institute for Brain Disorders Capital Medical University Beijing China
| | - Rongqiao He
- State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101China
- Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101China
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25
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Erickson JR, Nichols CB, Uchinoumi H, Stein ML, Bossuyt J, Bers DM. S-Nitrosylation Induces Both Autonomous Activation and Inhibition of Calcium/Calmodulin-dependent Protein Kinase II δ. J Biol Chem 2015; 290:25646-56. [PMID: 26316536 DOI: 10.1074/jbc.m115.650234] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Indexed: 01/15/2023] Open
Abstract
NO is known to modulate calcium handling and cellular signaling in the myocardium, but key targets for NO in the heart remain unidentified. Recent reports have implied that NO can activate calcium/calmodulin (Ca(2+)/CaM)-dependent protein kinase II (CaMKII) in neurons and the heart. Here we use our novel sensor of CaMKII activation, Camui, to monitor changes in the conformation and activation of cardiac CaMKII (CaMKIIδ) activity after treatment with the NO donor S-nitrosoglutathione (GSNO). We demonstrate that exposure to NO after Ca(2+)/CaM binding to CaMKIIδ results in autonomous kinase activation, which is abolished by mutation of the Cys-290 site. However, exposure of CaMKIIδ to GSNO prior to Ca(2+)/CaM exposure strongly suppresses kinase activation and conformational change by Ca(2+)/CaM. This NO-induced inhibition was ablated by mutation of the Cys-273 site. We found parallel effects of GSNO on CaM/CaMKIIδ binding and CaMKIIδ-dependent ryanodine receptor activation in adult cardiac myocytes. We conclude that NO can play a dual role in regulating cardiac CaMKIIδ activity.
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Affiliation(s)
- Jeffrey R Erickson
- From the Department of Physiology, University of Otago, Dunedin 9016, New Zealand and
| | - C Blake Nichols
- the Department of Pharmacology, University of California, Davis, CA 95616
| | - Hitoshi Uchinoumi
- the Department of Pharmacology, University of California, Davis, CA 95616
| | - Matthew L Stein
- the Department of Pharmacology, University of California, Davis, CA 95616
| | - Julie Bossuyt
- the Department of Pharmacology, University of California, Davis, CA 95616
| | - Donald M Bers
- the Department of Pharmacology, University of California, Davis, CA 95616
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26
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Differential expression of CaMKII isoforms and overall kinase activity in rat dorsal root ganglia after injury. Neuroscience 2015; 300:116-27. [PMID: 25982557 DOI: 10.1016/j.neuroscience.2015.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 05/01/2015] [Accepted: 05/06/2015] [Indexed: 11/21/2022]
Abstract
Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) decodes neuronal activity by translating cytoplasmic Ca(2+) signals into kinase activity that regulates neuronal functions including excitability, gene expression, and synaptic transmission. Four genes lead to developmental and differential expression of CaMKII isoforms (α, β, γ, δ). We determined mRNA levels of these isoforms in the dorsal root ganglia (DRG) of adult rats with and without nerve injury in order to determine if differential expression of CaMKII isoforms may contribute to functional differences that follow injury. DRG neurons express mRNA for all four isoforms, and the relative abundance of CaMKII isoforms was γ>α>β=δ, based on the CT values. Following ligation of the 5th lumbar (L5) spinal nerve (SNL), the β isoform did not change, but mRNA levels of both the γ and α isoforms were reduced in the directly injured L5 neurons, and the α isoform was reduced in L4 neurons, compared to their contemporary controls. In contrast, expression of the δ isoform mRNA increased in L5 neurons. CaMKII protein decreased following nerve injury in both L4 and L5 populations. Total CaMKII activity measured under saturating Ca(2+)/CaM conditions was decreased in both L4 and L5 populations, while autonomous CaMKII activity determined in the absence of Ca(2+) was selectively reduced in axotomized L5 neurons 21days after injury. Thus, loss of CaMKII signaling in sensory neurons after peripheral nerve injury may contribute to neuronal dysfunction and pain.
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27
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Simon B, Huart AS, Wilmanns M. Molecular mechanisms of protein kinase regulation by calcium/calmodulin. Bioorg Med Chem 2015; 23:2749-60. [PMID: 25963826 DOI: 10.1016/j.bmc.2015.04.051] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 04/13/2015] [Accepted: 04/15/2015] [Indexed: 01/02/2023]
Abstract
Many human protein kinases are regulated by the calcium-sensor protein calmodulin, which binds to a short flexible segment C-terminal to the enzyme's catalytic kinase domain. Our understanding of the molecular mechanism of kinase activity regulation by calcium/calmodulin has been advanced by the structures of two protein kinases-calmodulin kinase II and death-associated protein kinase 1-bound to calcium/calmodulin. Comparison of these two structures reveals a surprising level of diversity in the overall kinase-calcium/calmodulin arrangement and functional readout of activity, as well as complementary mechanisms of kinase regulation such as phosphorylation.
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Affiliation(s)
- Bertrand Simon
- EMBL Hamburg, c/o DESY, Building 25A, Notkestraße 85, 22603 Hamburg, Germany
| | - Anne-Sophie Huart
- EMBL Hamburg, c/o DESY, Building 25A, Notkestraße 85, 22603 Hamburg, Germany
| | - Matthias Wilmanns
- EMBL Hamburg, c/o DESY, Building 25A, Notkestraße 85, 22603 Hamburg, Germany.
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28
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Baucum AJ, Shonesy BC, Rose KL, Colbran RJ. Quantitative proteomics analysis of CaMKII phosphorylation and the CaMKII interactome in the mouse forebrain. ACS Chem Neurosci 2015; 6:615-31. [PMID: 25650780 PMCID: PMC4609176 DOI: 10.1021/cn500337u] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Ca(2+)/calmodulin-dependent protein kinase IIα (CaMKIIα) autophosphorylation at Thr286 and Thr305/Thr306 regulates kinase activity and modulates subcellular targeting and is critical for normal synaptic plasticity and learning and memory. Here, a mass spectrometry-based approach was used to identify Ca(2+)-dependent and -independent in vitro autophosphorylation sites in recombinant CaMKIIα and CaMKIIβ. CaMKII holoenzymes were then immunoprecipitated from subcellular fractions of forebrains isolated from either wild-type (WT) mice or mice with a Thr286 to Ala knock-in mutation of CaMKIIα (T286A-KI mice) and analyzed using the same approach in order to characterize in vivo phosphorylation sites in both CaMKII isoforms and identify CaMKII-associated proteins (CaMKAPs). A total of six and seven autophosphorylation sites in CaMKIIα and CaMKIIβ, respectively, were detected in WT mice. Thr286-phosphorylated CaMKIIα and Thr287-phosphorylated CaMKIIβ were selectively enriched in WT Triton-insoluble (synaptic) fractions compared to Triton-soluble (membrane) and cytosolic fractions. In contrast, Thr306-phosphorylated CaMKIIα and Ser315- and Thr320/Thr321-phosphorylated CaMKIIβ were selectively enriched in WT cytosolic fractions. The T286A-KI mutation significantly reduced levels of phosphorylation of CaMKIIα at Ser275 across all subcellular fractions and of cytosolic CaMKIIβ at Ser315 and Thr320/Thr321. Significantly more CaMKAPs coprecipitated with WT CaMKII holoenzymes in the synaptic fraction compared to that in the membrane fraction, with functions including scaffolding, microtubule organization, actin organization, ribosomal function, vesicle trafficking, and others. The T286A-KI mutation altered the interactions of multiple CaMKAPs with CaMKII, including several proteins linked to autism spectrum disorders. These data identify CaMKII isoform phosphorylation sites and a network of synaptic protein interactions that are sensitive to the abrogation of Thr286 autophosphorylation of CaMKIIα, likely contributing to the diverse synaptic and behavioral deficits of T286A-KI mice.
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Affiliation(s)
- Anthony J Baucum
- ⊥Department of Biology and Stark Neurosciences Research Institute, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
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IRBIT regulates CaMKIIα activity and contributes to catecholamine homeostasis through tyrosine hydroxylase phosphorylation. Proc Natl Acad Sci U S A 2015; 112:5515-20. [PMID: 25922519 DOI: 10.1073/pnas.1503310112] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Inositol 1,4,5-trisphosphate receptor (IP3R) binding protein released with IP3 (IRBIT) contributes to various physiological events (electrolyte transport and fluid secretion, mRNA polyadenylation, and the maintenance of genomic integrity) through its interaction with multiple targets. However, little is known about the physiological role of IRBIT in the brain. Here we identified calcium calmodulin-dependent kinase II alpha (CaMKIIα) as an IRBIT-interacting molecule in the central nervous system. IRBIT binds to and suppresses CaMKIIα kinase activity by inhibiting the binding of calmodulin to CaMKIIα. In addition, we show that mice lacking IRBIT present with elevated catecholamine levels, increased locomotor activity, and social abnormalities. The level of tyrosine hydroxylase (TH) phosphorylation by CaMKIIα, which affects TH activity, was significantly increased in the ventral tegmental area of IRBIT-deficient mice. We concluded that IRBIT suppresses CaMKIIα activity and contributes to catecholamine homeostasis through TH phosphorylation.
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30
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Coultrap SJ, Bayer KU. Nitric oxide induces Ca2+-independent activity of the Ca2+/calmodulin-dependent protein kinase II (CaMKII). J Biol Chem 2014; 289:19458-65. [PMID: 24855644 DOI: 10.1074/jbc.m114.558254] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Both signaling by nitric oxide (NO) and by the Ca(2+)/calmodulin (CaM)-dependent protein kinase II α isoform (CaMKIIα) are implicated in two opposing forms of synaptic plasticity underlying learning and memory, as well as in excitotoxic/ischemic neuronal cell death. For CaMKIIα, these functions specifically involve also Ca(2+)-independent autonomous activity, traditionally generated by Thr-286 autophosphorylation. Here, we demonstrate that NO-induced S-nitrosylation of CaMKIIα also directly generated autonomous activity, and that CaMKII inhibition protected from NO-induced neuronal cell death. NO induced S-nitrosylation at Cys-280/289, and mutation of either site abolished autonomy, indicating that simultaneous nitrosylation at both sites was required. Additionally, autonomy was generated only when Ca(2+)/CaM was present during NO exposure. Thus, generation of this form of CaMKIIα autonomy requires simultaneous signaling by NO and Ca(2+). Nitrosylation also significantly reduced subsequent CaMKIIα autophosphorylation specifically at Thr-286, but not at Thr-305. A previously described reduction of CaMKII activity by S-nitrosylation at Cys-6 was also observed here, but only after prolonged (>5 min) exposure to NO donors. These results demonstrate a novel regulation of CaMKII by another second messenger system and indicate its involvement in excitotoxic neuronal cell death.
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Affiliation(s)
- Steven J Coultrap
- From the Department of Pharmacology, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - K Ulrich Bayer
- From the Department of Pharmacology, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, Colorado 80045
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31
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Barcomb K, Buard I, Coultrap SJ, Kulbe JR, O'Leary H, Benke TA, Bayer KU. Autonomous CaMKII requires further stimulation by Ca2+/calmodulin for enhancing synaptic strength. FASEB J 2014; 28:3810-9. [PMID: 24843070 DOI: 10.1096/fj.14-250407] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A hallmark feature of Ca(2+)/calmodulin (CaM)-dependent protein kinase II (CaMKII) is generation of autonomous (Ca(2+)-independent) activity by T286 autophosphorylation. Biochemical studies have shown that "autonomous" CaMKII is ∼5-fold further stimulated by Ca(2+)/CaM, but demonstration of a physiological function for such regulation within cells has remained elusive. In this study, CaMKII-induced enhancement of synaptic strength in rat hippocampal neurons required both autonomous activity and further stimulation. Synaptic strength was decreased by CaMKIIα knockdown and rescued by reexpression, but not by mutants impaired for autonomy (T286A) or binding to NMDA-type glutamate receptor subunit 2B (GluN2B; formerly NR2B; I205K). Full rescue was seen with constitutively autonomous mutants (T286D), but only if they could be further stimulated (additional T305/306A mutation), and not with two other mutations that additionally impair Ca(2+)/CaM binding. Compared to rescue with wild-type CaMKII, the CaM-binding-impaired mutants even had reduced synaptic strength. One of these mutants (T305/306D) mimicked an inhibitory autophosphorylation of CaMKII, whereas the other one (Δstim) abolished CaM binding without introducing charged residues. Inhibitory T305/306 autophosphorylation also reduced GluN2B binding, but this effect was independent of reduced Ca(2+)/CaM binding and was not mimicked by T305/306D mutation. Thus, even autonomous CaMKII activity must be further stimulated by Ca(2+)/CaM for enhancement of synaptic strength.
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Affiliation(s)
| | | | | | | | - Heather O'Leary
- Department of Pharmacology and Department of Pediatrics, Section of Neurology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Timothy A Benke
- Department of Pharmacology and Department of Pediatrics, Section of Neurology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
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32
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Michalski PJ. The delicate bistability of CaMKII. Biophys J 2014; 105:794-806. [PMID: 23931327 DOI: 10.1016/j.bpj.2013.06.038] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 06/13/2013] [Accepted: 06/25/2013] [Indexed: 01/08/2023] Open
Abstract
Calcium/calmodulin-dependent protein kinase II (CaMKII) is a synaptic, autophosphorylating kinase that is essential for learning and memory. Previous models have suggested that CaMKII functions as a bistable switch that could be the molecular correlate of long-term memory, but experiments have failed to validate these predictions. These models involved significant approximations to overcome the combinatorial complexity inherent in a multisubunit, multistate system. Here, we develop a stochastic particle-based model of CaMKII activation and dynamics that overcomes combinatorial complexity without significant approximations. We report four major findings. First, the CaMKII model system is never bistable at resting calcium concentrations, which suggests that CaMKII activity does not function as the biochemical switch underlying long-term memory. Second, the steady-state activation curves are either laserlike or steplike. Both are characterized by a well-defined threshold for activation, which suggests that thresholding is a robust feature of this system. Third, transiently activated CaMKII can maintain its activity over the time course of many experiments, and such slow deactivation may account for the few reports of bistability in the literature. And fourth, under in vivo conditions, increases in phosphatase activity can increase CaMKII activity. This is a surprising and counterintuitive effect, as dephosphorylation is generally associated with CaMKII deactivation.
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Affiliation(s)
- P J Michalski
- Richard D. Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, Connecticut, USA.
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33
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Heijman J, Voigt N, Wehrens XHT, Dobrev D. Calcium dysregulation in atrial fibrillation: the role of CaMKII. Front Pharmacol 2014; 5:30. [PMID: 24624086 PMCID: PMC3940963 DOI: 10.3389/fphar.2014.00030] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 02/15/2014] [Indexed: 12/19/2022] Open
Abstract
Atrial fibrillation (AF) is the most frequently encountered clinical arrhythmia and is associated with increased morbidity and mortality. Ectopic activity and reentry are considered major arrhythmogenic mechanisms contributing to the initiation and maintenance of AF. In addition, AF is self-reinforcing through progressive electrical and structural remodeling which stabilize the arrhythmia and make it more difficult to treat. Recent research has suggested an important role for Ca(2+)-dysregulation in AF. Ca(2+)-handling abnormalities may promote ectopic activity, conduction abnormalities facilitating reentry, and AF-related remodeling. In this review article, we summarize the Ca(2+)-handling derangements occurring in AF and discuss their impact on fundamental arrhythmogenic mechanisms. We focus in particular on the role of the multifunctional Ca(2+)/calmodulin-dependent protein kinase type-II (CaMKII), which acts as a major link between Ca(2+)-dysregulation and arrhythmogenesis. CaMKII expression and activity are increased in AF and promote arrhythmogenesis through phosphorylation of various targets involved in cardiac electrophysiology and excitation-contraction coupling. We discuss the implications for potential novel therapeutic strategies for AF based on CaMKII and Ca(2+)-handling abnormalities.
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Affiliation(s)
- Jordi Heijman
- Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen Essen, Germany
| | - Niels Voigt
- Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen Essen, Germany
| | - Xander H T Wehrens
- Cardiovascular Research Institute, Departments of Molecular Physiology and Biophysics, and Medicine-Cardiology, Baylor College of Medicine Houston, TX, USA
| | - Dobromir Dobrev
- Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen Essen, Germany
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34
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Stratton M, Lee IH, Bhattacharyya M, Christensen SM, Chao LH, Schulman H, Groves JT, Kuriyan J. Activation-triggered subunit exchange between CaMKII holoenzymes facilitates the spread of kinase activity. eLife 2014; 3:e01610. [PMID: 24473075 PMCID: PMC3901001 DOI: 10.7554/elife.01610] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The activation of the dodecameric Ca(2+)/calmodulin dependent kinase II (CaMKII) holoenzyme is critical for memory formation. We now report that CaMKII has a remarkable property, which is that activation of the holoenzyme triggers the exchange of subunits between holoenzymes, including unactivated ones, enabling the calcium-independent phosphorylation of new subunits. We show, using a single-molecule TIRF microscopy technique, that the exchange process is triggered by the activation of CaMKII, and that exchange is modulated by phosphorylation of two residues in the calmodulin-binding segment, Thr 305 and Thr 306. Based on these results, and on the analysis of molecular dynamics simulations, we suggest that the phosphorylated regulatory segment of CaMKII interacts with the central hub of the holoenzyme and weakens its integrity, thereby promoting exchange. Our results have implications for an earlier idea that subunit exchange in CaMKII may have relevance for information storage resulting from brief coincident stimuli during neuronal signaling. DOI: http://dx.doi.org/10.7554/eLife.01610.001.
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Affiliation(s)
- Margaret Stratton
- Department of Molecular and Cell Biology, Berkeley, Berkeley, United States
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35
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Goh JJ, Manahan-Vaughan D. Role of inhibitory autophosphorylation of calcium/calmodulin-dependent kinase II (αCAMKII) in persistent (>24 h) hippocampal LTP and in LTD facilitated by novel object-place learning and recognition in mice. Behav Brain Res 2014; 285:79-88. [PMID: 24480420 DOI: 10.1016/j.bbr.2014.01.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/07/2014] [Accepted: 01/17/2014] [Indexed: 11/16/2022]
Abstract
Experience-dependent synaptic plasticity is widely expressed in the mammalian brain and is believed to underlie memory formation. Persistent forms of synaptic plasticity in the hippocampus, such as long-term potentiation (LTP) and long-term depression (LTD) are particularly of interest, as evidence is accumulating that they are expressed as a consequence of, or at the very least in association with, hippocampus-dependent novel learning events. Learning-facilitated plasticity describes the property of hippocampal synapses to express persistent synaptic plasticity when novel spatial learning is combined with afferent stimulation that is subthreshold for induction of changes in synaptic strength. In mice it occurs following novel object recognition and novel object-place recognition. Calmodulin-dependent kinase II (CAMKII) is strongly expressed in synapses and has been shown to be required for hippocampal LTP in vitro and for spatial learning in the water maze. Here, we show that in mice that undergo persistent inhibitory autophosphorylation of αCAMKII, object-place learning is intact. Furthermore, these animals demonstrate a higher threshold for induction of persistent (>24 h) hippocampal LTP in the hippocampal CA1 region during unrestrained behaviour. The transgenic mice also express short-term depression in response to afferent stimulation frequencies that are ineffective in controls. Furthermore, they express stronger LTD in response to novel learning of spatial configurations compared to controls. These findings support that modulation of αCAMKII activity via autophosphorylation at the Thr305/306 site comprises a key mechanism for the maintenance of synaptic plasticity within a dynamic range. They also indicate that a functional differentiation occurs in the way spatial information is encoded: whereas LTP is likely to be critically involved in the encoding of space per se, LTD appears to play a special role in the encoding of the content or features of space.
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Affiliation(s)
- Jinzhong Jeremy Goh
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Universitaetsstr. 150, MA 4/150, 44780 Bochum, Germany
| | - Denise Manahan-Vaughan
- Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Universitaetsstr. 150, MA 4/150, 44780 Bochum, Germany.
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Miller JB, Pratap A, Miyahara A, Zhou L, Bornemann S, Morris RJ, Oldroyd GE. Calcium/Calmodulin-dependent protein kinase is negatively and positively regulated by calcium, providing a mechanism for decoding calcium responses during symbiosis signaling. THE PLANT CELL 2013; 25:5053-66. [PMID: 24368786 PMCID: PMC3904005 DOI: 10.1105/tpc.113.116921] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The establishment of symbiotic associations in plants requires calcium oscillations that must be decoded to invoke downstream developmental programs. In animal systems, comparable calcium oscillations are decoded by calmodulin (CaM)-dependent protein kinases, but symbiotic signaling involves a calcium/CaM-dependent protein kinase (CCaMK) that is unique to plants. CCaMK differs from the animal CaM kinases by its dual ability to bind free calcium, via calcium binding EF-hand domains on the protein, or to bind calcium complexed with CaM, via a CaM binding domain. In this study, we dissect this dual regulation of CCaMK by calcium. We find that calcium binding to the EF-hand domains promotes autophosphorylation, which negatively regulates CCaMK by stabilizing the inactive state of the protein. By contrast, calcium-dependent CaM binding overrides the effects of autophosphorylation and activates the protein. The differential calcium binding affinities of the EF-hand domains compared with those of CaM suggest that CCaMK is maintained in the inactive state at basal calcium concentrations and is activated via CaM binding during calcium oscillations. This work provides a model for decoding calcium oscillations that uses differential calcium binding affinities to create a robust molecular switch that is responsive to calcium concentrations associated with both the basal state and with oscillations.
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Westenbrink BD, Edwards AG, McCulloch AD, Brown JH. The promise of CaMKII inhibition for heart disease: preventing heart failure and arrhythmias. Expert Opin Ther Targets 2013; 17:889-903. [PMID: 23789646 DOI: 10.1517/14728222.2013.809064] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Calcium-calmodulin-dependent protein kinase II (CaMKII) has emerged as a central mediator of cardiac stress responses which may serve several critical roles in the regulation of cardiac rhythm, cardiac contractility and growth. Sustained and excessive activation of CaMKII during cardiac disease has, however, been linked to arrhythmias, and maladaptive cardiac remodeling, eventually leading to heart failure (HF) and sudden cardiac death. AREAS COVERED In the current review, the authors describe the unique structural and biochemical properties of CaMKII and focus on its physiological effects in cardiomyocytes. Furthermore, they provide evidence for a role of CaMKII in cardiac pathologies, including arrhythmogenesis, myocardial ischemia and HF development. The authors conclude by discussing the potential for CaMKII as a target for inhibition in heart disease. EXPERT OPINION CaMKII provides a promising nodal point for intervention that may allow simultaneous prevention of HF progression and development of arrhythmias. For future studies and drug development there is a strong rationale for the development of more specific CaMKII inhibitors. In addition, an improved understanding of the differential roles of CaMKII subtypes is required.
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Affiliation(s)
- B Daan Westenbrink
- University of California, Department of Pharmacology, San Diego, La Jolla, CA, USA
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Stratton MM, Chao LH, Schulman H, Kuriyan J. Structural studies on the regulation of Ca2+/calmodulin dependent protein kinase II. Curr Opin Struct Biol 2013; 23:292-301. [PMID: 23632248 DOI: 10.1016/j.sbi.2013.04.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 03/24/2013] [Accepted: 04/02/2013] [Indexed: 11/15/2022]
Abstract
Ca(2+)/calmodulin dependent protein kinase II (CaMKII) is a broadly distributed metazoan Ser/Thr protein kinase that is important in neuronal and cardiac signaling. CaMKII forms oligomeric assemblies, typically dodecameric, in which the calcium-responsive kinase domains are organized around a central hub. We review the results of crystallographic analyses of CaMKII, including the recently determined structure of a full-length and autoinhibited form of the holoenzyme. These structures, when combined with other data, allow informed speculation about how CaMKII escapes calcium-dependence when calcium spikes exceed threshold frequencies.
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Affiliation(s)
- Margaret M Stratton
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
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40
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Ashpole NM, Chawla AR, Martin MP, Brustovetsky T, Brustovetsky N, Hudmon A. Loss of calcium/calmodulin-dependent protein kinase II activity in cortical astrocytes decreases glutamate uptake and induces neurotoxic release of ATP. J Biol Chem 2013; 288:14599-14611. [PMID: 23543737 DOI: 10.1074/jbc.m113.466235] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The extent of calcium/calmodulin-dependent protein kinase II (CaMKII) inactivation in the brain after ischemia correlates with the extent of damage. We have previously shown that a loss of CaMKII activity in neurons is detrimental to neuronal viability by inducing excitotoxic glutamate release. In the current study we extend these findings to show that the ability of astrocytes to buffer extracellular glutamate is reduced when CaMKII is inhibited. Furthermore, CaMKII inhibition in astrocytes is associated with the rapid onset of intracellular calcium oscillations. Surprisingly, this rapid calcium influx is blocked by the N-type calcium channel antagonist, ω-conotoxin. Although the function of N-type calcium channels within astrocytes is controversial, these voltage-gated calcium channels have been linked to calcium-dependent vesicular gliotransmitter release. When extracellular glutamate and ATP levels are measured after CaMKII inhibition within our enriched astrocyte cultures, no alterations in glutamate levels are observed, whereas ATP levels in the extracellular environment significantly increase. Extracellular ATP accumulation associated with CaMKII inhibition contributes both to calcium oscillations within astrocytes and ultimately cortical neuron toxicity. Thus, a loss of CaMKII signaling within astrocytes dysregulates glutamate uptake and supports ATP release, two processes that would compromise neuronal survival after ischemic/excitotoxic insults.
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Affiliation(s)
- Nicole M Ashpole
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Aarti R Chawla
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Matthew P Martin
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Tatiana Brustovetsky
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Nickolay Brustovetsky
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Andy Hudmon
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202; Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
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41
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Swaminathan PD, Purohit A, Hund TJ, Anderson ME. Calmodulin-dependent protein kinase II: linking heart failure and arrhythmias. Circ Res 2012; 110:1661-77. [PMID: 22679140 DOI: 10.1161/circresaha.111.243956] [Citation(s) in RCA: 215] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Understanding relationships between heart failure and arrhythmias, important causes of suffering and sudden death, remains an unmet goal for biomedical researchers and physicians. Evidence assembled over the past decade supports a view that activation of the multifunctional Ca(2+) and calmodulin-dependent protein kinase II (CaMKII) favors myocardial dysfunction and cell membrane electrical instability. CaMKII activation follows increases in intracellular Ca(2+) or oxidation, upstream signals with the capacity to transition CaMKII into a Ca(2+) and calmodulin-independent constitutively active enzyme. Constitutively active CaMKII appears poised to participate in disease pathways by catalyzing the phosphorylation of classes of protein targets important for excitation-contraction coupling and cell survival, including ion channels and Ca(2+) homeostatic proteins, and transcription factors that drive hypertrophic and inflammatory gene expression. This rich diversity of downstream targets helps to explain the potential for CaMKII to simultaneously affect mechanical and electrical properties of heart muscle cells. Proof-of-concept studies from a growing number of investigators show that CaMKII inhibition is beneficial for improving myocardial performance and for reducing arrhythmias. We review the molecular physiology of CaMKII and discuss CaMKII actions at key cellular targets and results of animal models of myocardial hypertrophy, dysfunction, and arrhythmias that suggest CaMKII inhibition may benefit myocardial function while reducing arrhythmias.
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Affiliation(s)
- Paari Dominic Swaminathan
- Division of Cardiovascular Medicine, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
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42
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Cui ZJ, Han ZQ, Li ZY. Modulating protein activity and cellular function by methionine residue oxidation. Amino Acids 2012; 43:505-17. [PMID: 22146868 DOI: 10.1007/s00726-011-1175-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 11/21/2011] [Indexed: 02/07/2023]
Abstract
The sulfur-containing amino acid residue methionine (Met) in a peptide/protein is readily oxidized to methionine sulfoxide [Met(O)] by reactive oxygen species both in vitro and in vivo. Methionine residue oxidation by oxidants is found in an accumulating number of important proteins. Met sulfoxidation activates calcium/calmodulin-dependent protein kinase II and the large conductance calcium-activated potassium channels, delays inactivation of the Shaker potassium channel ShC/B and L-type voltage-dependent calcium channels. Sulfoxidation at critical Met residues inhibits fibrillation of atherosclerosis-related apolipoproteins and multiple neurodegenerative disease-related proteins, such as amyloid beta, α-synuclein, prion, and others. Methionine residue oxidation is also correlated with marked changes in cellular activities. Controlled key methionine residue oxidation may be used as an oxi-genetics tool to dissect specific protein function in situ.
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Affiliation(s)
- Zong Jie Cui
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China.
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43
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Rosa AO, Movafagh S, Cleemann L, Morad M. Hypoxic regulation of cardiac Ca2+ channel: possible role of haem oxygenase. J Physiol 2012; 590:4223-37. [PMID: 22753548 DOI: 10.1113/jphysiol.2012.236570] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Acute and chronic hypoxias are common cardiac diseases that lead often to arrhythmia and impaired contractility. At the cellular level it is unclear whether the suppression of cardiac Ca(2+) channels (Ca(V)1.2) results directly from oxygen deprivation on the channel protein or is mediated by intermediary proteins affecting the channel. To address this question we measured the early effects of hypoxia (5-60 s, P(O(2)) < 5 mmHg) on Ca(2+) current (I(Ca)) and tested the involvement of protein kinase A (PKA) phosphorylation, Ca(2+)/calmodulin-mediated signalling and the haem oxygenase (HO) pathway in the hypoxic regulation of Ca(V)1.2 in rat and cat ventricular myocytes and HEK-293 cells. Hypoxic suppression of ICa) and Ca(2+) transients was significant within 5 s and intensified in the following 50 s, and was reversible. Phosphorylation by cAMP or the phosphatase inhibitor okadaic acid desensitized I(Ca) to hypoxia, while PKA inhibition by H-89 restored the sensitivity of I(Ca) to hypoxia. This phosphorylation effect was specific to Ca(2+), but not Ba(2+) or Na(+), permeating through the channel. CaMKII inhibitory peptide and Bay K8644 reversed the phosphorylation-induced desensitization to hypoxia. Mutation of CAM/CaMKII-binding motifs of the α(1c) subunit of Ca(V)1.2 fully desensitized the Ca(2+) channel to hypoxia. Rapid application of HO inhibitors (zinc protoporphyrin (ZnPP) and tin protoporphyrin (SnPP)) suppressed the channel in a manner similar to acute hypoxia such that: (1) I(Ca) and I(Ba) were suppressed within 5 s of ZnPP application; (2) PKA activation and CaMKII inhibitors desensitized I(Ca), but not I(Ba), to ZnPP; and (3) hypoxia failed to further suppress I(Ca) and I(Ba) in ZnPP-treated myocytes. We propose that the binding of HO to the CaM/CaMKII-specific motifs on Ca(2+) channel may mediate the rapid response of the channel to hypoxia.
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Affiliation(s)
- Angelo O Rosa
- Cardiac Signaling Center of University of South Carolina, Medical University of South Carolina and Clemson University, Charleston, SC 29245, USA
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44
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Coultrap SJ, Bayer KU. CaMKII regulation in information processing and storage. Trends Neurosci 2012; 35:607-18. [PMID: 22717267 DOI: 10.1016/j.tins.2012.05.003] [Citation(s) in RCA: 246] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 05/07/2012] [Accepted: 05/11/2012] [Indexed: 11/29/2022]
Abstract
The Ca(2+)/Calmodulin(CaM)-dependent protein kinase II (CaMKII) is activated by Ca(2+)/CaM, but becomes partially autonomous (Ca(2+)-independent) upon autophosphorylation at T286. This hallmark feature of CaMKII regulation provides a form of molecular memory and is indeed important in long-term potentiation (LTP) of excitatory synapse strength and memory formation. However, emerging evidence supports a direct role in information processing, while storage of synaptic information may instead be mediated by regulated interaction of CaMKII with the NMDA receptor (NMDAR) complex. These and other CaMKII regulation mechanisms are discussed here in the context of the kinase structure and their impact on postsynaptic functions. Recent findings also implicate CaMKII in long-term depression (LTD), as well as functional roles at inhibitory synapses, lending renewed emphasis on better understanding the spatiotemporal control of CaMKII regulation.
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Affiliation(s)
- Steven J Coultrap
- Department of Pharmacology, University of Colorado Denver School of Medicine, Aurora, CO 80045, USA
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45
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Michalski PJ, Loew LM. CaMKII activation and dynamics are independent of the holoenzyme structure: an infinite subunit holoenzyme approximation. Phys Biol 2012; 9:036010. [PMID: 22683827 DOI: 10.1088/1478-3975/9/3/036010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The combinatorial explosion produced by the multi-state, multi-subunit character of CaMKII has made analysis and modeling of this key signaling protein a significant challenge. Using rule-based and particle-based approaches, we construct exact models of CaMKII holoenzyme dynamics and study these models as a function of the number of subunits per holoenzyme, N. Without phosphatases the dynamics of activation are independent of the holoenzyme structure unless phosphorylation significantly alters the kinase activity of a subunit. With phosphatases the model is independent of holoenzyme size for N > 6. We introduce an infinite subunit holoenzyme approximation (ISHA), which simplifies the modeling by eliminating the combinatorial complexities encountered in any finite holoenzyme model. The ISHA is an excellent approximation to the full system over a broad range of physiologically relevant parameters. Finally, we demonstrate that the ISHA reproduces the behavior of exact models during synaptic plasticity protocols, which justifies its use as a module in large models of synaptic plasticity.
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Affiliation(s)
- P J Michalski
- Richard D Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, CT 06030, USA.
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46
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Coultrap SJ, Barcomb K, Bayer KU. A significant but rather mild contribution of T286 autophosphorylation to Ca2+/CaM-stimulated CaMKII activity. PLoS One 2012; 7:e37176. [PMID: 22615928 PMCID: PMC3353915 DOI: 10.1371/journal.pone.0037176] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 04/17/2012] [Indexed: 01/13/2023] Open
Abstract
Background Autophosphorylation of the Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) at T286 generates partially Ca2+/CaM-independent “autonomous” activity, which is thought to be required for long-term potentiation (LTP), a form of synaptic plasticity thought to underlie learning and memory. A requirement for T286 autophosphorylation also for efficient Ca2+/CaM-stimulated CaMKII activity has been described, but remains controversial. Methodology/Principal Findings In order to determine the contribution of T286 autophosphorylation to Ca2+/CaM-stimulated CaMKII activity, the activity of CaMKII wild type and its phosphorylation-incompetent T286A mutant was compared. As the absolute activity can vary between individual kinase preparations, the activity was measured in six different extracts for each kinase (expressed in HEK-293 cells). Consistent with measurements on purified kinase (from a baculovirus/Sf9 cell expression system), CaMKII T286A showed a mildly but significantly reduced rate of Ca2+/CaM-stimulated phosphorylation for two different peptide substrates (to ∼75–84% of wild type). Additional slower CaMKII autophosphorylation at T305/306 inhibits stimulation by Ca2+/CaM, but occurs only minimally for CaMKII wild type during CaM-stimulated activity assays. Thus, we tested if the T286A mutant may show more extensive inhibitory autophosphorylation, which could explain its reduced stimulated activity. By contrast, inhibitory autophosphorylation was instead found to be even further reduced for the T286A mutant under our assay conditions. On a side note, the phospho-T305 antibody showed some basal background immuno-reactivity also with non-phosphorylated CaMKII, as indicated by T305/306A mutants. Conclusions/Significance These results indicate that Ca2+/CaM-stimulated CaMKII activity is mildly (∼1.2–1.3fold) further increased by additional T286 autophosphorylation, but that this autophosphorylation is not required for the major part of the stimulated activity. This indicates that the phenotype of CaMKII T286A mutant mice is indeed due to the lack of autonomous activity, as the T286A mutant showed no dramatic reduction in stimulated activity.
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Affiliation(s)
- Steven J. Coultrap
- Department of Pharmacology, University of Colorado Denver – School of Medicine, Aurora, Colorado, United States of America
| | - Kelsey Barcomb
- Department of Pharmacology, University of Colorado Denver – School of Medicine, Aurora, Colorado, United States of America
| | - K. Ulrich Bayer
- Department of Pharmacology, University of Colorado Denver – School of Medicine, Aurora, Colorado, United States of America
- * E-mail:
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47
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Jalan-Sakrikar N, Bartlett RK, Baucum AJ, Colbran RJ. Substrate-selective and calcium-independent activation of CaMKII by α-actinin. J Biol Chem 2012; 287:15275-83. [PMID: 22427672 PMCID: PMC3346149 DOI: 10.1074/jbc.m112.351817] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 03/14/2012] [Indexed: 11/06/2022] Open
Abstract
Protein-protein interactions are thought to modulate the efficiency and specificity of Ca(2+)/calmodulin (CaM)-dependent protein kinase II (CaMKII) signaling in specific subcellular compartments. Here we show that the F-actin-binding protein α-actinin targets CaMKIIα to F-actin in cells by binding to the CaMKII regulatory domain, mimicking CaM. The interaction with α-actinin is blocked by CaMKII autophosphorylation at Thr-306, but not by autophosphorylation at Thr-305, whereas autophosphorylation at either site blocks Ca(2+)/CaM binding. The binding of α-actinin to CaMKII is Ca(2+)-independent and activates the phosphorylation of a subset of substrates in vitro. In intact cells, α-actinin selectively stabilizes CaMKII association with GluN2B-containing glutamate receptors and enhances phosphorylation of Ser-1303 in GluN2B, but inhibits CaMKII phosphorylation of Ser-831 in glutamate receptor GluA1 subunits by competing for activation by Ca(2+)/CaM. These data show that Ca(2+)-independent binding of α-actinin to CaMKII differentially modulates the phosphorylation of physiological targets that play key roles in long-term synaptic plasticity.
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Affiliation(s)
| | | | | | - Roger J. Colbran
- From the Department of Molecular Physiology and Biophysics
- Vanderbilt Brain Institute, and
- Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
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48
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Christian DT, Alexander NJ, Diaz MR, Robinson S, McCool BA. Chronic intermittent ethanol and withdrawal differentially modulate basolateral amygdala AMPA-type glutamate receptor function and trafficking. Neuropharmacology 2012; 62:2430-9. [PMID: 22387532 DOI: 10.1016/j.neuropharm.2012.02.017] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 02/15/2012] [Accepted: 02/16/2012] [Indexed: 12/19/2022]
Abstract
The amygdala plays a critical role in the generation and expression of anxiety-like behaviors including those expressed following withdrawal (WD) from chronic intermittent ethanol (CIE) exposure. In particular, the BLA glutamatergic system controls the expression of both innate and pathological anxiety. Recent data suggests that CIE and WD may functionally alter this system in a manner that closely parallels memory-related phenomena like long-term potentiation (LTP). We therefore specifically dissected CIE/WD-induced changes in glutamatergic signaling using electrophysiological and biochemical approaches with a particular focus on the plasticity-related components of this neurotransmitter system. Our results indicate that cortical glutamatergic inputs arriving at BLA principal via the external capsule undergo predominantly post-synaptic alterations in AMPA receptor function following CIE and WD. Biochemical analysis revealed treatment-dependent changes in AMPA receptor surface expression and subunit phosphorylation that are complemented by changes in total protein levels and/or phosphorylation status of several key, plasticity-associated protein kinases such as calcium/calmodulin-dependent protein kinase II (CaMKII) and protein kinase C (PKC). Together, these data show that CIE- and WD-induced changes in BLA glutamatergic function both functionally and biochemically mimic plasticity-related states. These mechanisms likely contribute to long-term increases in anxiety-like behavior following chronic ethanol exposure.
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Affiliation(s)
- Daniel T Christian
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
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49
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Chao LH, Stratton MM, Lee IH, Rosenberg OS, Levitz J, Mandell DJ, Kortemme T, Groves JT, Schulman H, Kuriyan J. A mechanism for tunable autoinhibition in the structure of a human Ca2+/calmodulin- dependent kinase II holoenzyme. Cell 2011; 146:732-45. [PMID: 21884935 DOI: 10.1016/j.cell.2011.07.038] [Citation(s) in RCA: 190] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 05/11/2011] [Accepted: 07/29/2011] [Indexed: 01/16/2023]
Abstract
Calcium/calmodulin-dependent kinase II (CaMKII) forms a highly conserved dodecameric assembly that is sensitive to the frequency of calcium pulse trains. Neither the structure of the dodecameric assembly nor how it regulates CaMKII are known. We present the crystal structure of an autoinhibited full-length human CaMKII holoenzyme, revealing an unexpected compact arrangement of kinase domains docked against a central hub, with the calmodulin-binding sites completely inaccessible. We show that this compact docking is important for the autoinhibition of the kinase domains and for setting the calcium response of the holoenzyme. Comparison of CaMKII isoforms, which differ in the length of the linker between the kinase domain and the hub, demonstrates that these interactions can be strengthened or weakened by changes in linker length. This equilibrium between autoinhibited states provides a simple mechanism for tuning the calcium response without changes in either the hub or the kinase domains.
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Affiliation(s)
- Luke H Chao
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
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50
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Coultrap SJ, Bayer KU. Improving a natural CaMKII inhibitor by random and rational design. PLoS One 2011; 6:e25245. [PMID: 21984908 PMCID: PMC3184957 DOI: 10.1371/journal.pone.0025245] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 08/30/2011] [Indexed: 11/18/2022] Open
Abstract
Background CaM-KIIN has evolved to inhibit stimulated and autonomous activity of the Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) efficiently, selectively, and potently (IC50 ∼100 nM). The CN class of peptides, derived from the inhibitory region of CaM-KIIN, provides powerful new tools to study CaMKII functions. The goal of this study was to identify the residues required for CaMKII inhibition, and to assess if artificial mutations could further improve the potency achieved during evolution. Methodology/Principal Findings First, the minimal region with full inhibitory potency was identified (CN19) by determining the effect of truncated peptides on CaMKII activity in biochemical assays. Then, individual residues of CN19 were mutated. Most individual Ala substitutions decreased potency of CaMKII inhibition, however, P3A, K13A, and R14A increased potency. Importantly, this initial Ala scan suggested a specific interaction of the region around R11 with the CaMKII substrate binding site, which was exploited for further rational mutagenesis to generate an optimized pseudo-substrate sequence. Indeed, the potency of the optimized peptide CN19o was >250fold improved (IC50 <0.4 nM), and CN19o has characteristics of a tight-binding inhibitor. The selectivity for CaMKII versus CaMKI was similarly improved (to almost 100,000fold for CN19o). A phospho-mimetic S12D mutation decreased potency, indicating potential for regulation by cellular signaling. Consistent with importance of this residue in inhibition, most other S12 mutations also significantly decreased potency, however, mutation to V or Q did not. Conlusions/Significance These results provide improved research tools for studying CaMKII function, and indicate that evolution fine-tuned CaM-KIIN not for maximal potency of CaMKII inhibition, but for lower potency that may be optimal for dynamic regulation of signal transduction.
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Affiliation(s)
- Steven J. Coultrap
- Department of Pharmacology, University of Colorado Denver - School of Medicine, Aurora, Colorado, United States of America
| | - K. Ulrich Bayer
- Department of Pharmacology, University of Colorado Denver - School of Medicine, Aurora, Colorado, United States of America
- * E-mail:
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