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Ohtsuka S, Miyai Y, Mima H, Magari M, Chiba Y, Suizu F, Sakagami H, Ueno M, Tokumitsu H. Transcriptional, biochemical, and immunohistochemical analyses of CaMKKβ/2 splice variants that co-localize with CaMKIV in spermatids. Cell Calcium 2024; 117:102820. [PMID: 37979343 DOI: 10.1016/j.ceca.2023.102820] [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: 07/28/2023] [Revised: 10/18/2023] [Accepted: 10/29/2023] [Indexed: 11/20/2023]
Abstract
Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) phosphorylates and activates downstream protein kinases, including CaMKI, CaMKIV, PKB/Akt, and AMPK; thus, regulates various Ca2+-dependent physiological and pathophysiological pathways. Further, CaMKKβ/2 in mammalian species comprises multiple alternatively spliced variants; however, their functional differences or redundancy remain unclear. In this study, we aimed to characterize mouse CaMKKβ/2 splice variants (CaMKKβ-3 and β-3x). RT-PCR analyses revealed that mouse CaMKKβ-1, consisting of 17 exons, was predominantly expressed in the brain; whereas, mouse CaMKKβ-3 and β-3x, lacking exon 16 and exons 14/16, respectively, were primarily expressed in peripheral tissues. At the protein level, the CaMKKβ-3 or β-3x variants showed high expression levels in mouse cerebrum and testes. This was consistent with the localization of CaMKKβ-3/-3x in spermatids in seminiferous tubules, but not the localization of CaMKKβ-1. We also observed the co-localization of CaMKKβ-3/-3x with a target kinase, CaMKIV, in elongating spermatids. Biochemical characterization further revealed that CaMKKβ-3 exhibited Ca2+/CaM-induced kinase activity similar to CaMKKβ-1. Conversely, we noted that CaMKKβ-3x impaired Ca2+/CaM-binding ability, but exhibited significantly weak autonomous activity (approximately 500-fold lower than CaMKKβ-1 or β-3) due to the absence of C-terminal of the catalytic domain and a putative residue (Ile478) responsible for the kinase autoinhibition. Nevertheless, CaMKKβ-3x showed the ability to phosphorylate downstream kinases, including CaMKIα, CaMKIV, and AMPKα in transfected cells comparable to CaMKKβ-1 and β-3. Collectively, CaMKKβ-3/-3x were identified as functionally active and could be bona fide CaMKIV-kinases in testes involved in the activation of the CaMKIV cascade in spermatids, resulting in the regulation of spermiogenesis.
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Affiliation(s)
- Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Yumi Miyai
- Inflammation Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Hiroyuki Mima
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Yoichi Chiba
- Inflammation Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Futoshi Suizu
- Oncology Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Kanagawa, 252-0374, Japan
| | - Masaki Ueno
- Inflammation Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan.
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Yoshida A, Ito A, Yasui N, Yamashita A. Direct binding of calmodulin to the cytosolic C-terminal regions of sweet/umami taste receptors. J Biochem 2023; 174:451-459. [PMID: 37527916 PMCID: PMC11033526 DOI: 10.1093/jb/mvad060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/15/2023] [Accepted: 07/26/2023] [Indexed: 08/03/2023] Open
Abstract
Sweet and umami taste receptors recognize chemicals such as sugars and amino acids on their extracellular side and transmit signals into the cytosol of the taste cell. In contrast to ligands that act on the extracellular side of these receptors, little is known regarding the molecules that regulate receptor functions within the cytosol. In this study, we analysed the interaction between sweet and umami taste receptors and calmodulin, a representative Ca2+-dependent cytosolic regulatory protein. High prediction scores for calmodulin binding were observed on the C-terminal cytosolic side of mouse taste receptor type 1 subunit 3 (T1r3), a subunit that is common to both sweet and umami taste receptors. Pull-down assay and surface plasmon resonance analyses showed different affinities of calmodulin to the C-terminal tails of distinct T1r subtypes. Furthermore, we found that T1r3 and T1r2 showed the highest and considerable binding to calmodulin, whereas T1r1 showed weaker binding affinity. Finally, the binding of calmodulin to T1rs was consistently higher in the presence of Ca2+ than in its absence. The results suggested a possibility of the Ca2+-dependent feedback regulation process of sweet and umami taste receptor signaling by calmodulin.
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Affiliation(s)
- Atsuki Yoshida
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Ayumi Ito
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Norihisa Yasui
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Atsuko Yamashita
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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3
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Nakamura KN, Yamauchi H, Mima H, Yerun C, Ohtsuka S, Magari M, Morishita R, Tokumitsu H. Rapid detection of calmodulin/target interaction via the proximity biotinylation method. Biochem Biophys Res Commun 2023; 659:29-33. [PMID: 37031591 DOI: 10.1016/j.bbrc.2023.03.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 03/29/2023] [Indexed: 04/04/2023]
Abstract
Calmodulin (CaM) is known to function as a central signal transducer in calcium-mediated intracellular pathways. In this study, a fusion molecule of a recently developed proximity biotinylation enzyme (AirID) with rat CaM (AirID-CaM) was expressed and purified to near homogeneity using an E. coli expression system to examine the physical interactions between CaM and its target proteins by converting the interaction to biotinylation of CaM targets under nondenatured conditions. AirID-CaM catalyzed a Ca2+-dependent biotinylation of a target protein kinase (Ca2+/CaM-dependent protein kinase kinase α/1, CaMKKα/1) in vitro, which was suppressed by the addition of excess amounts of CaM, and AirID alone did not catalyze the biotinylation of CaMKKα/1, indicating that the biotinylation of CaMKKα/1 by AirID-CaM likely occurs in an interaction-dependent manner. Furthermore, we also observed the Ca2+-dependent biotinylation of GST-CaMKIα and GST-CaMKIV by AirID-CaM, suggesting that AirID-CaM can be useful for the rapid detection of CaM/target interactions with relatively high sensitivity.
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Kaneshige R, Ohtsuka S, Harada Y, Kawamata I, Magari M, Kanayama N, Hatano N, Sakagami H, Tokumitsu H. Substrate recognition by Arg/Pro-rich insert domain in calcium/calmodulin-dependent protein kinase kinase for target protein kinases. FEBS J 2022; 289:5971-5984. [PMID: 35490408 DOI: 10.1111/febs.16467] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/14/2022] [Accepted: 04/28/2022] [Indexed: 02/01/2023]
Abstract
Calcium/calmodulin-dependent protein kinase kinases (CaMKKs) activate CaMKI, CaMKIV, protein kinase B/Akt, and AMP-activated protein kinase (AMPK) by phosphorylating Thr residues in activation loops to mediate various Ca2+ -signaling pathways. Mammalian cells expressing CaMKKα and CaMKKβ lacking Arg/Pro-rich insert domain (RP-domain) sequences showed impaired phosphorylation of AMPKα, CaMKIα, and CaMKIV, whereas the autophosphorylation activities of CaMKK mutants remained intact and were similar to those of wild-type CaMKKs. Liver kinase B1 (LKB1, an AMPK kinase) complexed with STRAD and MO25 and was unable to phosphorylate CaMKIα and CaMKIV; however, mutant LKB1 with the RP-domain sequences of CaMKKα and CaMKKβ inserted between kinase subdomains II and III acquired CaMKIα and CaMKIV phosphorylating activity in vitro and in transfected cultured cells. Furthermore, ionomycin-induced phosphorylation of hemagglutinin (HA)-CaMKIα at Thr177, HA-CaMKIV at Thr196, and HA-AMPKα at Thr172 in transfected cells was significantly suppressed by cotransfection of kinase-dead mutants of CaMKK isoforms, but these dominant-negative effects were abrogated with RP-deletion mutants, suggesting that sequestration of substrate kinases by loss-of-function CaMKK mutants requires the RP-domain. This was confirmed by pulldown experiments that showed that dominant-negative mutants of CaMKKα and CaMKKβ interact with target kinases but not RP-deletion mutants. Taken together, these results clearly indicate that both CaMKK isoforms require the RP-domain to recognize downstream kinases to interact with and phosphorylate Thr residues in their activation loops. Thus, the RP-domain may be a promising target for specific CaMKK inhibitors.
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Affiliation(s)
- Riku Kaneshige
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Japan
| | - Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Japan
| | - Yuhei Harada
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Japan
| | - Issei Kawamata
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama University, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Japan
| | - Naoki Kanayama
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Japan
| | - Naoya Hatano
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Japan
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Japan
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Ohtsuka S, Okumura T, Τabuchi Y, Miyagawa T, Kanayama N, Magari M, Hatano N, Sakagami H, Suizu F, Ishikawa T, Tokumitsu H. Conformation-Dependent Reversible Interaction of Ca 2+/Calmodulin-Dependent Protein Kinase Kinase with an Inhibitor, TIM-063. Biochemistry 2022; 61:545-553. [PMID: 35274528 DOI: 10.1021/acs.biochem.1c00796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ca2+/calmodulin-dependent protein kinase kinase (CaMKK), a Ca2+/CaM-dependent enzyme that phosphorylates and activates multifunctional kinases, including CaMKI, CaMKIV, protein kinase B/Akt, and 5'AMP-activated protein kinase, is involved in various Ca2+-signaling pathways in cells. Recently, we developed an ATP-competitive CaMKK inhibitor, TIM-063 (2-hydroxy-3-nitro-7H-benzo[de]benzo[4,5]imidazo[2,1-a]isoquinolin-7-one, Ohtsuka et al. Biochemistry 2020, 59, 1701-1710). To gain mechanistic insights into the interaction of CaMKK with TIM-063, we prepared TIM-063-coupled sepharose (TIM-127-sepharose) for association/dissociation analysis of the enzyme/inhibitor complex. CaMKKα/β in transfected COS-7 cells and in mouse brain extracts specifically bound to TIM-127-sepharose and dissociated following the addition of TIM-063 in a manner similar to that of recombinant GST-CaMKKα/β, which could bind to TIM-127-sepharose in a Ca2+/CaM-dependent fashion and dissociate from the sepharose following the addition of TIM-063 in a dose-dependent manner. In contrast to GST-CaMKKα, GST-CaMKKβ was able to weakly bind to TIM-127-sepharose in the presence of EGTA, probably due to the partially active conformation of recombinant GST-CaMKKβ without Ca2+/CaM-binding. These results suggested that the regulatory domain of CaMKKα prevented the inhibitor from interacting with the catalytic domain as the GST-CaMKKα mutant (residues 126-434) lacking the regulatory domain (residues 438-463) interacted with TIM-127-sepharose regardless of the presence or absence of Ca2+/CaM. Furthermore, CaMKKα bound to TIM-127-sepharose in the presence of Ca2+/CaM completely dissociated from TIM-127-sepharose following the addition of excess EGTA. These results indicated that TIM-063 interacted with and inhibited CaMKK in its active state but not in its autoinhibited state and that this interaction is likely reversible, depending on the concentration of intracellular Ca2+.
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Affiliation(s)
- Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Taisei Okumura
- Department of Science Education, Graduate School of Education, Okayama University, Okayama 700-8530, Japan
| | - Yuna Τabuchi
- Department of Science Education, Graduate School of Education, Okayama University, Okayama 700-8530, Japan
| | - Tomoyuki Miyagawa
- Department of Science Education, Graduate School of Education, Okayama University, Okayama 700-8530, Japan
| | - Naoki Kanayama
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Naoya Hatano
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Futoshi Suizu
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo 060-0815, Japan
| | - Teruhiko Ishikawa
- Department of Science Education, Graduate School of Education, Okayama University, Okayama 700-8530, Japan
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
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6
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Fukumoto Y, Harada Y, Ohtsuka S, Kanayama N, Magari M, Hatano N, Sakagami H, Tokumitsu H. Oligomerization of Ca 2+/calmodulin-dependent protein kinase kinase. Biochem Biophys Res Commun 2022; 587:160-165. [PMID: 34875535 DOI: 10.1016/j.bbrc.2021.11.105] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 11/30/2021] [Indexed: 11/28/2022]
Abstract
Ca2+/calmodulin-dependent protein kinase kinases (CaMKKα and β) are regulatory kinases for multiple downstream kinases, including CaMKI, CaMKIV, PKB/Akt, and AMP-activated protein kinase (AMPK) through phosphorylation of each activation-loop Thr residue. In this report, we biochemically characterize the oligomeric structure of CaMKK isoforms through a heterologous expression system using COS-7 cells. Oligomerization of CaMKK isoforms was readily observed by treating CaMKK transfected cells with cell membrane permeable crosslinkers. In addition, His-tagged CaMKKα (His-CaMKKα) pulled down with FLAG-tagged CaMKKα (FLAG-CaMKKα) in transfected cells. The oligomerization of CaMKKα was confirmed by the fact that GST-CaMKKα/His-CaMKKα complex from transiently expressed COS-7 cells extracts was purified to near homogeneity by the sequential chromatography using glutathione-sepharose/Ni-sepharose and was observed in a Ca2+/CaM-independent manner by reciprocal pulldown assay, suggesting the direct interaction between monomeric CaMKKα. Furthermore, the His-CaMKKα kinase-dead mutant (D293A) complexed with FLAG-CaMKKα exhibited significant CaMKK activity, indicating the active CaMKKα multimeric complex. Collectively, these results suggest that CaMKKα can self-associate in the cells, constituting a catalytically active oligomer that might be important for the efficient activation of CaMKK-mediated intracellular signaling.
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Affiliation(s)
- Yusei Fukumoto
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Yuhei Harada
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Naoki Kanayama
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Naoya Hatano
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Kanagawa, 252-0374, Japan
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan.
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7
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Akizuki K, Ono A, Xue H, Kameshita I, Ishida A, Sueyoshi N. Biochemical characterization of four splice variants of mouse Ca2+/calmodulin-dependent protein kinase Iδ. J Biochem 2021; 169:445-458. [PMID: 33417706 DOI: 10.1093/jb/mvaa117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/14/2020] [Indexed: 11/12/2022] Open
Abstract
Ca2+/calmodulin (CaM)-dependent protein kinase Iδ (CaMKIδ) is a Ser/Thr kinase that plays pivotal roles in Ca2+ signalling. CaMKIδ is activated by Ca2+/CaM-binding and phosphorylation at Thr180 by CaMK kinase (CaMKK). In this study, we characterized four splice variants of mouse CaMKIδ (mCaMKIδs: a, b, c and d) found by in silico analysis. Recombinant mCaMKIδs expressed in Escherichia coli were phosphorylated by CaMKK; however, only mCaMKIδ-a and c showed protein kinase activities towards myelin basic protein in vitro, with mCaMKIδ-b and mCaMKIδ-d being inactive. Although mCaMKIδ-a and mCaMKIδ-c underwent autophosphorylation in vitro, only mCaMKIδ-c underwent autophosphorylation in 293T cells. Site-directed mutagenesis showed that the autophosphorylation site is Ser349, which is found in the C-terminal region of only variants c and b (Ser324). Furthermore, phosphorylation of these sites (Ser324 and Ser349) in mCaMKIδ-b and c was more efficiently catalyzed by cAMP-dependent protein kinase in vitro and in cellulo as compared to the autophosphorylation of mCaMKIδ-c. Thus, variants of mCaMKIδ possess distinct properties in terms of kinase activities, autophosphorylation and phosphorylation by another kinase, suggesting that they play physiologically different roles in murine cells.
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Affiliation(s)
- Kazutoshi Akizuki
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kagawa 761-0795, Japan.,Research Fellow of Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083, Japan.,Laboratory of Molecular Brain Science, Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Ayaka Ono
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kagawa 761-0795, Japan
| | - Houcheng Xue
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kagawa 761-0795, Japan
| | - Isamu Kameshita
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kagawa 761-0795, Japan
| | - Atsuhiko Ishida
- Laboratory of Molecular Brain Science, Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Noriyuki Sueyoshi
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kagawa 761-0795, Japan
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Yamamoto M, Kondo R, Hozumi H, Doi S, Denda M, Magari M, Kanayama N, Hatano N, Morishita R, Tokumitsu H. Identification and Biochemical Characterization of High Mobility Group Protein 20A as a Novel Ca 2+/S100A6 Target. Biomolecules 2021; 11:biom11040510. [PMID: 33808200 PMCID: PMC8103281 DOI: 10.3390/biom11040510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/17/2021] [Accepted: 03/23/2021] [Indexed: 12/30/2022] Open
Abstract
During screening of protein-protein interactions, using human protein arrays carrying 19,676 recombinant glutathione s-transferase (GST)-fused human proteins, we identified the high-mobility protein group 20A (HMG20A) as a novel S100A6 binding partner. We confirmed the Ca2+-dependent interaction of HMG20A with S100A6 by the protein array method, biotinylated S100A6 overlay, and GST-pulldown assay in vitro and in transfected COS-7 cells. Co-immunoprecipitation of S100A6 with HMG20A from HeLa cells in a Ca2+-dependent manner revealed the physiological relevance of the S100A6/HMG20A interaction. In addition, HMG20A has the ability to interact with S100A1, S100A2, and S100B in a Ca2+-dependent manner, but not with S100A4, A11, A12, and calmodulin. S100A6 binding experiments using various HMG20A mutants revealed that Ca2+/S100A6 interacts with the C-terminal region (residues 311–342) of HMG20A with stoichiometric binding (HMG20A:S100A6 dimer = 1:1). This was confirmed by the fact that a GST-HMG20A mutant lacking the S100A6 binding region (residues 311–347, HMG20A-ΔC) failed to interact with endogenous S100A6 in transfected COS-7 cells, unlike wild-type HMG20A. Taken together, these results identify, for the first time, HMG20A as a target of Ca2+/S100 proteins, and may suggest a novel linkage between Ca2+/S100 protein signaling and HMG20A function, including in the regulation of neural differentiation.
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Affiliation(s)
- Maho Yamamoto
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan; (M.Y.); (R.K.); (S.D.); (M.M.); (N.K.); (N.H.)
| | - Rina Kondo
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan; (M.Y.); (R.K.); (S.D.); (M.M.); (N.K.); (N.H.)
| | - Haruka Hozumi
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Okayama University, Okayama 700-8530, Japan;
| | - Seita Doi
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan; (M.Y.); (R.K.); (S.D.); (M.M.); (N.K.); (N.H.)
| | - Miwako Denda
- Cell Free Sciences Co., Ltd., Matsuyama 790-8577, Japan; (M.D.); (R.M.)
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan; (M.Y.); (R.K.); (S.D.); (M.M.); (N.K.); (N.H.)
| | - Naoki Kanayama
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan; (M.Y.); (R.K.); (S.D.); (M.M.); (N.K.); (N.H.)
| | - Naoya Hatano
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan; (M.Y.); (R.K.); (S.D.); (M.M.); (N.K.); (N.H.)
| | - Ryo Morishita
- Cell Free Sciences Co., Ltd., Matsuyama 790-8577, Japan; (M.D.); (R.M.)
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan; (M.Y.); (R.K.); (S.D.); (M.M.); (N.K.); (N.H.)
- Correspondence: ; Tel.: +81-86-251-8197
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Zheng L, Chenavas S, Kieken F, Trease A, Brownell S, Anbanandam A, Sorgen PL, Spagnol G. Calmodulin Directly Interacts with the Cx43 Carboxyl-Terminus and Cytoplasmic Loop Containing Three ODDD-Linked Mutants (M147T, R148Q, and T154A) that Retain α-Helical Structure, but Exhibit Loss-of-Function and Cellular Trafficking Defects. Biomolecules 2020; 10:biom10101452. [PMID: 33080786 PMCID: PMC7602980 DOI: 10.3390/biom10101452] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/13/2020] [Accepted: 10/14/2020] [Indexed: 12/14/2022] Open
Abstract
The autosomal-dominant pleiotropic disorder called oculodentodigital dysplasia (ODDD) is caused by mutations in the gap junction protein Cx43. Of the 73 mutations identified to date, over one-third are localized in the cytoplasmic loop (Cx43CL) domain. Here, we determined the mechanism by which three ODDD mutations (M147T, R148Q, and T154A), all of which localize within the predicted 1-5-10 calmodulin-binding motif of the Cx43CL, manifest the disease. Nuclear magnetic resonance (NMR) and circular dichroism revealed that the three ODDD mutations had little-to-no effect on the ability of the Cx43CL to form α-helical structure as well as bind calmodulin. Combination of microscopy and a dye-transfer assay uncovered these mutations increased the intracellular level of Cx43 and those that trafficked to the plasma membrane did not form functional channels. NMR also identify that CaM can directly interact with the Cx43CT domain. The Cx43CT residues involved in the CaM interaction overlap with tyrosines phosphorylated by Pyk2 and Src. In vitro and in cyto data provide evidence that the importance of the CaM interaction with the Cx43CT may lie in restricting Pyk2 and Src phosphorylation, and their subsequent downstream effects.
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Affiliation(s)
- Li Zheng
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (L.Z.); (S.C.); (F.K.); (A.T.); (S.B.)
| | - Sylvie Chenavas
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (L.Z.); (S.C.); (F.K.); (A.T.); (S.B.)
| | - Fabien Kieken
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (L.Z.); (S.C.); (F.K.); (A.T.); (S.B.)
| | - Andrew Trease
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (L.Z.); (S.C.); (F.K.); (A.T.); (S.B.)
| | - Sarah Brownell
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (L.Z.); (S.C.); (F.K.); (A.T.); (S.B.)
| | - Asokan Anbanandam
- Biomolecular NMR Core Facility, University of Kansas, Lawrence, KS 66045, USA;
| | - Paul L. Sorgen
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (L.Z.); (S.C.); (F.K.); (A.T.); (S.B.)
- Correspondence: (P.L.S.); (G.S.)
| | - Gaelle Spagnol
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (L.Z.); (S.C.); (F.K.); (A.T.); (S.B.)
- Correspondence: (P.L.S.); (G.S.)
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10
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Juhász T, Kardos J, Dürvanger Z, Harmat V, Liliom K. Comparison of ligand binding and conformational stability of human calmodulin with its homolog from the malaria parasite Plasmodium falciparum. FASEB Bioadv 2020; 2:489-505. [PMID: 32821880 PMCID: PMC7429351 DOI: 10.1096/fba.2020-00013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 03/24/2020] [Accepted: 06/16/2020] [Indexed: 11/11/2022] Open
Abstract
Calmodulin (CaM), the key calcium sensor of eukaryotic cells regulating a great number of target proteins, belongs to the most conserved proteins. We compared function and properties of CaMs from two evolutionarily distant species, the human (Homo sapiens) representing vertebrates, and the malaria parasite Plasmodium falciparum (Pf). The biophysical characterization revealed higher stability of Pf CaM attributed to the more stable C-terminal domain in both Ca2+ free and saturated states. In vitro binding and functional assays demonstrated that human and Pf CaM exhibit similar biochemical features involving small molecule inhibitor binding and target enzyme activation as illustrated by comparable affinities differing only within a factor of three. It has been reported that CaM antagonists proved to be antimalarials, so Pf CaM could be a potential target to combat malaria parasites. Indeed, we observed that phenotypically active compounds from the Malaria Box could show inhibitory action on Pf CaM, among them the most potent exhibited comparable inhibition to known antagonists of vertebrate CaM. However, based on the minor binding differences in Pf CaM to human CaM, we conclude that CaM is an unsuited target for human intervention against malaria, due to the likely interference with the host protein.
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Affiliation(s)
- Tünde Juhász
- Institute of Materials and Environmental ChemistryResearch Centre for Natural SciencesBudapestHungary
| | - József Kardos
- Department of BiochemistryInstitute of BiologyELTE Eötvös Loránd UniversityBudapestHungary
| | - Zsolt Dürvanger
- Laboratory of Structural Chemistry and BiologyInstitute of ChemistryEötvös Loránd UniversityBudapestHungary
| | - Veronika Harmat
- Laboratory of Structural Chemistry and BiologyInstitute of ChemistryEötvös Loránd UniversityBudapestHungary
- MTA‐ELTE Protein Modelling Research GroupBudapestHungary
| | - Károly Liliom
- Department of Biophysics and Radiation BiologyFaculty of MedicineSemmelweis UniversityBudapestHungary
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11
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Osawa J, Akizuki K, Kashimura A, Ueta S, Nakatani M, Inui Y, Shigeri Y, Ishida A, Kameshita I, Sueyoshi N. Dual phosphorylation of protein phosphatase PPM1H promotes dephosphorylation of Smad1 in cellulo. Biochem Biophys Res Commun 2020; 530:513-519. [PMID: 32600616 DOI: 10.1016/j.bbrc.2020.05.082] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 05/13/2020] [Indexed: 01/08/2023]
Abstract
Protein phosphatase PPM1H is known to participate in various biological or pathophysiological mechanisms. However, little is known about the molecular mechanisms of its regulation. In this study, we investigated the protein kinases that directly phosphorylate PPM1H, identifying them as cAMP-dependent protein kinase (PKA) and Ca2+/calmodulin-dependent protein kinase I (CaMKI). In vitro and in silico analyses showed that the phosphorylation sites of PPM1H by PKA and CaMKI were Ser-123 and Ser-210, respectively. The phosphorylation state of PPM1H in cells exhibited the kinase activator- and inhibitor-dependent changes. In mouse neuroblastoma Neuro2a cells, phosphorylation of Ser-210 was much higher in the phospho-mimetic mutant (S123D) than in the non-phosphorylatable mutant (S123A) when they were treated with ionomycin. This suggests that a hierarchical phosphorylation, with initial phosphorylation of Ser-123 promoting subsequent phosphorylation of Ser-210, occurs in these neuron-like cells. Moreover, in cell-based assay a PPM1H(S123A/S210A) double mutant barely dephosphorylated Smad1, a transcription factor known as an endogenous substrate of PPM1H. These results suggest that cAMP and Ca2+/calmodulin regulate dephosphorylation of Smad1 through the dual phosphorylation of PPM1H at Ser-123 and Ser-210.
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Affiliation(s)
- Jin Osawa
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan
| | - Kazutoshi Akizuki
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan; Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739-8521, Japan
| | - Akari Kashimura
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan
| | - Saki Ueta
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan
| | - Misato Nakatani
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan
| | - Yuiko Inui
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan
| | - Yasushi Shigeri
- Department of Chemistry, Wakayama Medical University, 580 Mikazura, Wakayama, 641-0011, Japan
| | - Atsuhiko Ishida
- Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739-8521, Japan.
| | - Isamu Kameshita
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan
| | - Noriyuki Sueyoshi
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795, Japan.
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12
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Millana Fañanás E, Todesca S, Sicorello A, Masino L, Pompach P, Magnani F, Pastore A, Mattevi A. On the mechanism of calcium-dependent activation of NADPH oxidase 5 (NOX5). FEBS J 2020; 287:2486-2503. [PMID: 31785178 PMCID: PMC7317449 DOI: 10.1111/febs.15160] [Citation(s) in RCA: 17] [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: 10/14/2019] [Accepted: 11/27/2019] [Indexed: 12/15/2022]
Abstract
It is now accepted that reactive oxygen species (ROS) are not only dangerous oxidative agents but also chemical mediators of the redox cell signaling and innate immune response. A central role in ROS-controlled production is played by the NADPH oxidases (NOXs), a group of seven membrane-bound enzymes (NOX1-5 and DUOX1-2) whose unique function is to produce ROS. Here, we describe the regulation of NOX5, a widespread family member present in cyanobacteria, protists, plants, fungi, and the animal kingdom. We show that the calmodulin-like regulatory EF-domain of NOX5 is partially unfolded and detached from the rest of the protein in the absence of calcium. In the presence of calcium, the C-terminal lobe of the EF-domain acquires an ordered and more compact structure that enables its binding to the enzyme dehydrogenase (DH) domain. Our spectroscopic and mutagenesis studies further identified a set of conserved aspartate residues in the DH domain that are essential for NOX5 activation. Altogether, our work shows that calcium induces an unfolded-to-folded transition of the EF-domain that promotes direct interaction with a conserved regulatory region, resulting in NOX5 activation.
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Affiliation(s)
- Elisa Millana Fañanás
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
| | - Sofia Todesca
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
| | - Alessandro Sicorello
- UK Dementia Research Institute at King's College LondonUK
- The Wohl Institute at King's College LondonUK
| | | | - Petr Pompach
- Institute of BiotechnologyCzech Academy of SciencesVestecCzech Republic
- Institute of MicrobiologyCzech Academy of SciencesPragueCzech Republic
| | - Francesca Magnani
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
| | - Annalisa Pastore
- UK Dementia Research Institute at King's College LondonUK
- The Wohl Institute at King's College LondonUK
| | - Andrea Mattevi
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
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13
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Grb7-derived calmodulin-binding peptides inhibit proliferation, migration and invasiveness of tumor cells while they enhance attachment to the substrate. Heliyon 2020; 6:e03922. [PMID: 32420488 PMCID: PMC7215194 DOI: 10.1016/j.heliyon.2020.e03922] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 02/05/2020] [Accepted: 04/30/2020] [Indexed: 12/28/2022] Open
Abstract
The growth factor receptor bound protein 7 (Grb7) is a Ca2+-dependent calmodulin (CaM)-binding adaptor protein implicated, among other functions, in cell proliferation, migration and tumor-associated angiogenesis. The goal of this study was to determine whether a peptide based on the CaM binding site of Grb7 disrupts cellular processes, relevant for the malignancy of tumor cells, in which this adaptor protein is implicated. We designed synthetic myristoylated and non-myristoylated peptides corresponding to the CaM-binding domain of human Grb7 with the sequence 243RKLWKRFFCFLRRS256 and a variant peptide with the mutated sequence RKLERFFCFLRRE (W246E-ΔK247-S256E). The two non-myristoylated peptides bind dansyl-CaM with higher efficiency in the presence than in the absence of Ca2+ and they enter into the cell, as tested with 5(6)-carboxytetramethylrhodamine (TAMRA)-labeled peptides. The myristoylated and non-myristoylated peptides inhibit the proliferation, migration and invasiveness of A431 tumor cells while they enhance their adhesion to the substrate. The myristoylated peptides have stronger inhibitory effect than the non-myristoylated counterparts, in agreement with their expected higher cell-permeant capacity. The myristoylated and non-myristoylated W246E-ΔK247-S256E mutant peptide has a lesser inhibitory effect on cell proliferation as compared to the wild-type peptide. We also demonstrated that the myristoylated peptides were more efficient than the CaM antagonist N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) inhibiting cell migration and equally efficient inhibiting cell proliferation.
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14
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Ohtsuka S, Ozeki Y, Fujiwara M, Miyagawa T, Kanayama N, Magari M, Hatano N, Suizu F, Ishikawa T, Tokumitsu H. Development and Characterization of Novel Molecular Probes for Ca 2+/Calmodulin-Dependent Protein Kinase Kinase, Derived from STO-609. Biochemistry 2020; 59:1701-1710. [PMID: 32298102 DOI: 10.1021/acs.biochem.0c00149] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) activates particular multifunctional kinases, including CaMKI, CaMKIV, and 5'AMP-activated protein kinase (AMPK), resulting in the regulation of various Ca2+-dependent cellular processes, including neuronal, metabolic, and pathophysiological pathways. We developed and characterized a novel pan-CaMKK inhibitor, TIM-063 (2-hydroxy-3-nitro-7H-benzo[de]benzo[4,5]imidazo[2,1-a]isoquinolin-7-one) derived from STO-609 (7H-benzimidazo[2,1-a]benz[de]isoquinoline-7-one-3-carboxylic acid), and an inactive analogue (TIM-062) as molecular probes for the analysis of CaMKK-mediated cellular responses. Unlike STO-609, TIM-063 had an inhibitory activity against CaMKK isoforms (CaMKKα and CaMKKβ) with a similar potency (Ki = 0.35 μM for CaMKKα, and Ki = 0.2 μM for CaMKKβ) in vitro. Two TIM-063 analogues lacking a nitro group (TIM-062) or a hydroxy group (TIM-064) completely impaired CaMKK inhibitory activities, indicating that both substituents are necessary for the CaMKK inhibitory activity of TIM-063. Enzymatic analysis revealed that TIM-063 is an ATP-competitive inhibitor that directly targets the catalytic domain of CaMKK, similar to STO-609. TIM-063 suppressed the ionomycin-induced phosphorylation of exogenously expressed CaMKI, CaMKIV, and endogenous AMPKα in HeLa cells with an IC50 of ∼0.3 μM, and it suppressed CaMKK isoform-mediated CaMKIV phosphorylation in transfected COS-7 cells. Thus, TIM-063, but not the inactive analogue (TIM-062), displayed cell permeability and the ability to inhibit CaMKK activity in cells. Taken together, these results indicate that TIM-063 could be a useful tool for the precise analysis of CaMKK-mediated signaling pathways and may be a promising lead compound for the development of therapeutic agents for the treatment of CaMKK-related diseases.
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Affiliation(s)
- Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | | | | | | | - Naoki Kanayama
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Naoya Hatano
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Futoshi Suizu
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo 060-0815, Japan
| | | | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science & Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
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15
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Watson GM, Wilce JA. Direct Interaction between Calmodulin and the Grb7 RA-PH Domain. Int J Mol Sci 2020; 21:ijms21041336. [PMID: 32079204 PMCID: PMC7073000 DOI: 10.3390/ijms21041336] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/11/2020] [Accepted: 02/15/2020] [Indexed: 01/18/2023] Open
Abstract
Grb7 is a signalling adapter protein that engages activated receptor tyrosine kinases at cellular membranes to effect downstream pathways of cell migration, proliferation and survival. Grb7’s cellular location was shown to be regulated by the small calcium binding protein calmodulin (CaM). While evidence for a Grb7/CaM interaction is compelling, a direct interaction between CaM and purified Grb7 has not been demonstrated and quantitated. In this study we sought to determine this, and prepared pure full-length Grb7, as well as its RA-PH and SH2 subdomains, and tested for CaM binding using surface plasmon resonance. We report a direct interaction between full-length Grb7 and CaM that occurs in a calcium dependent manner. While no binding was observed to the SH2 domain alone, we observed a high micromolar affinity interaction between the Grb7 RA-PH domain and CaM, suggesting that the Grb7/CaM interaction is mediated through this region of Grb7. Together, our data support the model of a CaM interaction with Grb7 via its RA-PH domain.
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16
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Akizuki K, Kinumi T, Ono A, Senga Y, Osawa J, Shigeri Y, Ishida A, Kameshita I, Sueyoshi N. Autoactivation of C-terminally truncated Ca2+/calmodulin-dependent protein kinase (CaMK) Iδ via CaMK kinase-independent autophosphorylation. Arch Biochem Biophys 2019; 668:29-38. [DOI: 10.1016/j.abb.2019.05.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/25/2019] [Accepted: 05/05/2019] [Indexed: 01/01/2023]
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17
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Levin A, Cinar S, Paulus M, Nase J, Winter R, Czeslik C. Analyzing protein-ligand and protein-interface interactions using high pressure. Biophys Chem 2019; 252:106194. [PMID: 31177023 DOI: 10.1016/j.bpc.2019.106194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 05/29/2019] [Accepted: 05/29/2019] [Indexed: 01/06/2023]
Abstract
All protein function is based on interactions with the environment. Proteins can bind molecules for their transport, their catalytic conversion, or for signal transduction. They can bind to each other, and they adsorb at interfaces, such as lipid membranes or material surfaces. An experimental characterization is needed to understand the underlying mechanisms, but also to make use of proteins in biotechnology or biomedicine. When protein interactions are studied under high pressure, volume changes are revealed that directly describe spatial contributions to these interactions. Moreover, the strength of protein interactions with ligands or interfaces can be tuned in a smooth way by pressure modulation, which can be utilized in the design of drugs and bio-responsive interfaces. In this short review, selected studies of protein-ligand and protein-interface interactions are presented that were carried out under high pressure. Furthermore, a perspective on bio-responsive interfaces is given where protein-ligand binding is applied to create functional interfacial structures.
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Affiliation(s)
- Artem Levin
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
| | - Süleyman Cinar
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
| | - Michael Paulus
- Technische Universität Dortmund, Fakultät Physik/Delta, D-44221 Dortmund, Germany
| | - Julia Nase
- Technische Universität Dortmund, Fakultät Physik/Delta, D-44221 Dortmund, Germany
| | - Roland Winter
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
| | - Claus Czeslik
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany.
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18
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Takata T, Tsukuda A, Tsuchiya Y, Akaike T, Watanabe Y. The active-site cysteine residue of Ca 2+/calmodulin-dependent protein kinase I is protected from irreversible modification via generation of polysulfidation. Nitric Oxide 2019; 86:68-75. [PMID: 30844494 DOI: 10.1016/j.niox.2019.02.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/14/2019] [Accepted: 02/21/2019] [Indexed: 11/30/2022]
Abstract
Ca2+/calmodulin (CaM)-dependent protein kinase (CaMK) I is activated by the phosphorylation of a crucial activation loop Thr177 by upstream kinases, CaMK kinase (CaMKK), and regulates axonal or dendritic extension and branching. Reactive sulfur species (RSS) modulate protein functions via polysulfidation of the reactive Cys residues. Here, we report that the activity of CaMKI was reversibly inhibited via its polysulfidation at Cys179 by RSS. In vitro incubation of CaMKI with the exogenous RSS donor Na2S3 resulted in a dose-dependent inhibition of the phosphorylation at Thr177 by CaMKK and inactivation of the enzymatic activity. Dithiothreitol (DTT), a small molecule reducing reagent, rescued these inhibitions. Conversely, mutated CaMKI (C179V) was resistant to the Na2S3-induced inactivation. In transfected cells expressing CaMKI, ionomycin-induced CaMKI activity was decreased upon treatment with Na2S4, whereas cells expressing mutant CaMKI (C179V) proved resistant to this treatment. A biotin-polyethylene glycol-conjugated maleimide capture assay revealed that CaMKI was a target for polysulfidation in cells. Furthermore, the polysulfidation of CaMKI protected Cys179 from its irreversible modification, known as protein succination. Thus, we propose that CaMKI was reversibly inhibited via polysulfidation of Cys179 by RSS, thereby protecting it from irreversible modification.
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Affiliation(s)
- Tsuyoshi Takata
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo, 194-8543, Japan
| | - Ayaka Tsukuda
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo, 194-8543, Japan
| | - Yukihiro Tsuchiya
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo, 194-8543, Japan
| | - Takaaki Akaike
- Department of Environmental Health Sciences and Molecular Toxicology, Graduate School of Medicine, Tohoku University, Miyagi, 980-8575, Japan
| | - Yasuo Watanabe
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo, 194-8543, Japan.
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19
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Takabatake S, Ohtsuka S, Sugawara T, Hatano N, Kanayama N, Magari M, Sakagami H, Tokumitsu H. Regulation of Ca 2+/calmodulin-dependent protein kinase kinase β by cAMP signaling. Biochim Biophys Acta Gen Subj 2019; 1863:672-680. [PMID: 30660766 DOI: 10.1016/j.bbagen.2018.12.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/03/2018] [Accepted: 12/18/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) is a pivotal activator of CaMKI, CaMKIV and 5'-AMP-activated protein kinase (AMPK), controlling Ca2+-dependent intracellular signaling including various neuronal, metabolic and pathophysiological responses. Recently, we demonstrated that CaMKKβ is feedback phosphorylated at Thr144 by the downstream AMPK, resulting in the conversion of CaMKKβ into Ca2+/CaM-dependent enzyme. However, the regulatory phosphorylation of CaMKKβ at Thr144 in intact cells and in vivo remains unclear. METHODS Anti-phosphoThr144 antibody was used to characterize the site-specific phosphorylation of CaMKKβ in immunoprecipitated samples from mouse cerebellum and in transfected mammalian cells that were treated with various agonists and protein kinase inhibitors. CaMKK activity assay and LC-MS/MS analysis were used for biochemical characterization of phosphorylated CaMKKβ. RESULTS Our data suggest that the phosphorylation of Thr144 in CaMKKβ is rapidly induced by cAMP/cAMP-dependent protein kinase (PKA) signaling in CaMKKβ-transfected HeLa cells, that is physiologically relevant in mouse cerebellum. We confirmed that the catalytic subunit of PKA was capable of directly phosphorylating CaMKKβ at Thr144 in vitro and in transfected cells. In addition, the basal phosphorylation of CaMKKβ at Thr144 in transfected HeLa cells was suppressed by AMPK inhibitor (compound C). PKA-catalyzed phosphorylation reduced the autonomous activity of CaMKKβ in vitro without significant effect on the Ca2+/CaM-dependent activity, resulting in the conversion of CaMKKβ into Ca2+/CaM-dependent enzyme. CONCLUSION cAMP/PKA signaling may confer Ca2+-dependency to the CaMKKβ-mediated signaling pathway through direct phosphorylation of Thr144 in intact cells. GENERAL SIGNIFICANCE Our results suggest a novel cross-talk between cAMP/PKA and Ca2+/CaM/CaMKKβ signaling through regulatory phosphorylation.
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Affiliation(s)
- Shota Takabatake
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Takeyuki Sugawara
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Naoya Hatano
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Naoki Kanayama
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan.
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20
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Araki S, Takata T, Tsuchiya Y, Watanabe Y. Reactive sulfur species impair Ca2+/calmodulin-dependent protein kinase II via polysulfidation. Biochem Biophys Res Commun 2019; 508:550-555. [DOI: 10.1016/j.bbrc.2018.11.134] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 11/20/2018] [Indexed: 11/30/2022]
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21
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Takata T, Kimura J, Ihara H, Hatano N, Tsuchiya Y, Watanabe Y. Redox regulation of Ca 2+/calmodulin-dependent protein kinase IV via oxidation of its active-site cysteine residue. Free Radic Biol Med 2019; 130:99-106. [PMID: 30394289 DOI: 10.1016/j.freeradbiomed.2018.10.440] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 09/15/2018] [Accepted: 10/24/2018] [Indexed: 11/15/2022]
Abstract
We have recently reported that Ca2+/calmodulin (CaM)-dependent protein kinase IV (CaMKIV) is inactivated by reactive sulfur species via polysulfidation of the active-site Cys residue. Here, we show that hydrogen peroxide (H2O2) limit CaMKIV activity at the same active-site Cys residue through oxidation and downstream signaling in cells. CaMKIV is phosphorylated at Thr196 by its upstream CaMK kinase (CaMKK), which induces its full activity. In vitro incubation of CaMKIV with H2O2 resulted in reversible inhibition of CaMKK-induced phospho-Thr196 and the consequent inactivation of CaMKIV. In contrast, mutated CaMKIV (C198V) was refractory to the H2O2-induced enzyme inhibition. In transfected cells expressing CaMKIV, Ca2+ ionophore-induced CaMKIV phosphorylation at Thr196 was decreased upon treatment with H2O2, whereas cells expressing mutant CaMKIV (C198V) were resistant to H2O2 treatment. Modification of free thiol with N-ethylmaleimide revealed that Cys198 in CaMKIV is a target for S-oxidation. Additionally, the Ca2+ influx-induced phospho-Thr196 of endogenous CaMKIV was also inhibited upon treatment with H2O2 in Jurkat T-lymphocytes and cerebellar granule cells. Phosphorylation of cyclic AMP response element-binding protein (CREB) at Ser133, which is downstream of CaMKIV, was also decreased upon treatment with H2O2. Thus, our results indicate that oxidation stress regulates cellular function by decreasing the activity of CaMKIV through Cys198 oxidation.
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Affiliation(s)
- Tsuyoshi Takata
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | - Jun Kimura
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | - Hideshi Ihara
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai 599-8531, Osaka, Japan
| | - Naoya Hatano
- The Integrated Center for Mass Spectrometry, Kobe University, Graduate School of Medicine, Kobe 650-0017, Japan
| | - Yukihiro Tsuchiya
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | - Yasuo Watanabe
- Department of Pharmacology, High Technology Research Center, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan.
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Khan S, Downing KH, Molloy JE. Architectural Dynamics of CaMKII-Actin Networks. Biophys J 2018; 116:104-119. [PMID: 30527447 PMCID: PMC6341221 DOI: 10.1016/j.bpj.2018.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 11/02/2018] [Accepted: 11/06/2018] [Indexed: 11/24/2022] Open
Abstract
Calcium-calmodulin-dependent kinase II (CaMKII) has an important role in dendritic spine remodeling upon synaptic stimulation. Using fluorescence video microscopy and image analysis, we investigated the architectural dynamics of rhodamine-phalloidin stabilized filamentous actin (F-actin) networks cross-linked by CaMKII. We used automated image analysis to identify F-actin bundles and crossover junctions and developed a dimensionless metric to characterize network architecture. Similar networks were formed by three different CaMKII species with a 10-fold length difference in the linker region between the kinase domain and holoenzyme hub, implying linker length is not a primary determinant of F-actin cross-linking. Electron micrographs showed that at physiological molar ratios, single CaMKII holoenzymes cross-linked multiple F-actin filaments at random, whereas at higher CaMKII/F-actin ratios, filaments bundled. Light microscopy established that the random network architecture resisted macromolecular crowding with polyethylene glycol and blocked ATP-powered compaction by myosin-II miniature filaments. Importantly, the networks disassembled after the addition of calcium-calmodulin and were then spaced within 3 min into compacted foci by myosin motors or more slowly (30 min) aggregated by crowding. Single-molecule total internal reflection fluorescence microscopy showed CaMKII dissociation from surface-immobilized globular actin exhibited a monoexponential dwell-time distribution, whereas CaMKII bound to F-actin networks had a long-lived fraction, trapped at crossover junctions. Release of CaMKII from F-actin, triggered by calcium-calmodulin, was too rapid to measure with flow-cell exchange (<20 s). The residual bound fraction was reduced substantially upon addition of an N-methyl-D-aspartate receptor peptide analog but not ATP. These results provide mechanistic insights to CaMKII-actin interactions at the collective network and single-molecule level. Our findings argue that CaMKII-actin networks in dendritic spines maintain spine size against physical stress. Upon synaptic stimulation, CaMKII is disengaged by calcium-calmodulin, triggering network disassembly, expansion, and subsequent compaction by myosin motors with kinetics compatible with the times recorded for the poststimulus changes in spine volume.
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Affiliation(s)
- Shahid Khan
- Molecular Biology Consortium, Lawrence Berkeley National Laboratory, Berkeley, California; The Francis Crick Institute, London, United Kingdom.
| | - Kenneth H Downing
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, California
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Levin A, Czeslik C. Interaction of calmodulin with poly(acrylic acid) brushes: Effects of high pressure, pH-value and ligand binding. Colloids Surf B Biointerfaces 2018; 171:478-484. [DOI: 10.1016/j.colsurfb.2018.07.073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/26/2018] [Accepted: 07/30/2018] [Indexed: 12/12/2022]
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Ueno S, Miyoshi H, Maruyama Y, Morita M, Maekawa S. Interaction of dynamin I with NAP-22, a neuronal protein enriched in the presynaptic region. Neurosci Lett 2018; 675:59-63. [PMID: 29604406 DOI: 10.1016/j.neulet.2018.03.061] [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] [Received: 02/27/2018] [Revised: 03/24/2018] [Accepted: 03/28/2018] [Indexed: 10/17/2022]
Abstract
Neurons have well-developed membrane microdomains called "rafts" that are recovered as a detergent-resistant low-density membrane microdomain fraction (DRM). NAP-22 is one of the major protein components of neuronal DRM and localizes in the presynaptic region. In order to know the role of NAP-22 in the synaptic transmission, NAP-22 binding proteins in the cytosol were searched with an affinity screening with NAP-22 as a bait and several protein bands were detected. Using mass-analysis and western blotting, one of the main band of ∼90 kDa was identified as dynamin I. The GTPase activity of dynamin I was partly inhibited by NAP-22 expressed in bacteria and this inhibition was recovered by the addition of calmodulin, a NAP-22 binding protein. The GTPase activity of dynamin was known to be activated with acidic membrane lipids such as phosphatidylserine and the addition of NAP-22, a phosphatidylserine binding protein, inhibited the activation of the GTPase by this lipid. Since NAP-22 localizes on the presynaptic plasma membrane and on synaptic vesicles, these results suggest the participation of NAP-22 in the membrane cycling through binding to dynamin and acidic membrane lipids at the presynaptic region.
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Affiliation(s)
- Satoko Ueno
- Department of Biology, Graduate School of Science, Kobe-University, Kobe, 657-8501, Japan
| | - Hiroshi Miyoshi
- Department of Microbiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae, Kawasaki, 216-8511, Japan
| | - Yoko Maruyama
- Department of Biology, Graduate School of Science, Kobe-University, Kobe, 657-8501, Japan
| | - Mitsuhiro Morita
- Department of Biology, Graduate School of Science, Kobe-University, Kobe, 657-8501, Japan
| | - Shohei Maekawa
- Department of Biology, Graduate School of Science, Kobe-University, Kobe, 657-8501, Japan.
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25
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Cinar S, Czeslik C. Inhibitor and peptide binding to calmodulin characterized by high pressure Fourier transform infrared spectroscopy and Förster resonance energy transfer. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:617-623. [DOI: 10.1016/j.bbapap.2018.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/09/2018] [Accepted: 03/15/2018] [Indexed: 10/17/2022]
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26
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Maruyama Y, Ueno S, Morita M, Hayashi F, Maekawa S. Inhibitory effect of several sphingolipid metabolites on calcineurin. Neurosci Lett 2018. [PMID: 29524645 DOI: 10.1016/j.neulet.2018.03.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Neurons have well-developed membrane microdomains called "rafts" that are recovered as a detergent-resistant membrane microdomain fraction (DRM). NAP-22 is one of the major protein components of neuronal DRM. In a previous study, we showed that DRM-derived NAP-22 binds ganglioside and the inhibitory effect of ganglioside to calcineurin (CaN), a neuron-enriched calmodulin-regulated phosphoprotein phosphatase. Considering the important roles of CaN in neurons, identification of other cellular regulators of CaN could be a good clue to understand the molecular background of neuronal function. In this study, we screened the effect of several membrane lipid-derived molecules on the CaN activity and found sphingosine and some sphingosine-derived metabolites such as sphingosylphosphorylcholine, galactosylsphingosine (psychosine), and glucosylsphingosine, have inhibitory effect on CaN through the interaction with calmodulin.
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Affiliation(s)
- Yoko Maruyama
- Department of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan
| | - Satoko Ueno
- Department of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan
| | - Mitsuhiro Morita
- Department of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan
| | - Fumio Hayashi
- Department of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan
| | - Shohei Maekawa
- Department of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan.
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27
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Cinar S, Al-Ayoubi S, Sternemann C, Peters J, Winter R, Czeslik C. A high pressure study of calmodulin-ligand interactions using small-angle X-ray and elastic incoherent neutron scattering. Phys Chem Chem Phys 2018; 20:3514-3522. [PMID: 29336441 DOI: 10.1039/c7cp07399b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calmodulin (CaM) is a Ca2+ sensor and mediates Ca2+ signaling through binding of numerous target ligands. The binding of ligands by Ca2+-saturated CaM (holo-CaM) is governed by attractive hydrophobic and electrostatic interactions that are weakened under high pressure in aqueous solutions. Moreover, the potential formation of void volumes upon ligand binding creates a further source of pressure sensitivity. Hence, high pressure is a suitable thermodynamic variable to probe protein-ligand interactions. In this study, we compare the binding of two different ligands to holo-CaM as a function of pressure by using X-ray and neutron scattering techniques. The two ligands are the farnesylated hypervariable region (HVR) of the K-Ras4B protein, which is a natural binding partner of holo-CaM, and the antagonist trifluoperazine (TFP), which is known to inhibit holo-CaM activity. From small-angle X-ray scattering experiments performed up to 3000 bar, we observe a pressure-induced partial unfolding of the free holo-CaM in the absence of ligands, where the two lobes of the dumbbell-shaped protein are slightly swelled. In contrast, upon binding TFP, holo-CaM forms a closed globular conformation, which is pressure stable at least up to 3000 bar. The HVR of K-Ras4B shows a different binding behavior, and the data suggest the dissociation of the holo-CaM/HVR complex under high pressure, probably due to a less dense protein contact of the HVR as compared to TFP. The elastic incoherent neutron scattering experiments corroborate these findings. Below 2000 bar, pressure induces enhanced atomic fluctuations in both holo-CaM/ligand complexes, but those of the holo-CaM/HVR complex seem to be larger. Thus, the inhibition of holo-CaM by TFP is supported by a low-volume ligand binding, albeit this is not associated with a rigidification of the complex structure on the sub-ns Å-scale.
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Affiliation(s)
- Süleyman Cinar
- Department of Chemistry and Chemical Biology, TU Dortmund University, D-44221 Dortmund, Germany.
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Nakanishi A, Hatano N, Fujiwara Y, Sha'ri A, Takabatake S, Akano H, Kanayama N, Magari M, Nozaki N, Tokumitsu H. AMP-activated protein kinase-mediated feedback phosphorylation controls the Ca 2+/calmodulin (CaM) dependence of Ca 2+/CaM-dependent protein kinase kinase β. J Biol Chem 2017; 292:19804-19813. [PMID: 28974582 DOI: 10.1074/jbc.m117.805085] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 09/18/2017] [Indexed: 11/06/2022] Open
Abstract
The Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ)/5'-AMP-activated protein kinase (AMPK) phosphorylation cascade affects various Ca2+-dependent metabolic pathways and cancer growth. Unlike recombinant CaMKKβ that exhibits higher basal activity (autonomous activity), activation of the CaMKKβ/AMPK signaling pathway requires increased intracellular Ca2+ concentrations. Moreover, the Ca2+/CaM dependence of CaMKKβ appears to arise from multiple phosphorylation events, including autophosphorylation and activities furnished by other protein kinases. However, the effects of proximal downstream kinases on CaMKKβ activity have not yet been evaluated. Here, we demonstrate feedback phosphorylation of CaMKKβ at multiple residues by CaMKKβ-activated AMPK in addition to autophosphorylation in vitro, leading to reduced autonomous, but not Ca2+/CaM-activated, CaMKKβ activity. MS analysis and site-directed mutagenesis of AMPK phosphorylation sites in CaMKKβ indicated that Thr144 phosphorylation by activated AMPK converts CaMKKβ into a Ca2+/CaM-dependent enzyme as shown by completely Ca2+/CaM-dependent CaMKK activity of a phosphomimetic T144E CaMKKβ mutant. CaMKKβ mutant analysis indicated that the C-terminal domain (residues 471-587), including the autoinhibitory region, plays an important role in stabilizing an inactive conformation in a Thr144 phosphorylation-dependent manner. Furthermore, immunoblot analysis with anti-phospho-Thr144 antibody revealed phosphorylation of Thr144 in CaMKKβ in transfected COS-7 cells that was further enhanced by exogenous expression of AMPKα. These results indicate that AMPK-mediated feedback phosphorylation of CaMKKβ regulates the CaMKKβ/AMPK signaling cascade and may be physiologically important for intracellular maintenance of Ca2+-dependent AMPK activation by CaMKKβ.
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Affiliation(s)
- Akihiro Nakanishi
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Naoya Hatano
- The Integrated Center for Mass Spectrometry, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan, and
| | - Yuya Fujiwara
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Arian Sha'ri
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Shota Takabatake
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Hiroki Akano
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Naoki Kanayama
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Masaki Magari
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | | | - Hiroshi Tokumitsu
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan,
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Cinar S, Czeslik C. Bioresponsive interfaces composed of calmodulin and poly(ethylene glycol): Toggling the interfacial film thickness by protein-ligand binding. Colloids Surf B Biointerfaces 2017; 158:9-15. [PMID: 28658645 DOI: 10.1016/j.colsurfb.2017.06.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 06/14/2017] [Accepted: 06/20/2017] [Indexed: 11/25/2022]
Abstract
Responsive interfaces are often realized by polymer films that change their structure and properties upon changing the pH-value, ionic strength or temperature. Here, we present a bioresponsive interfacial structure that is based on a protein, calmodulin (CaM), which undergoes a huge conformational change upon ligand binding. At first, we characterize the conformational functionality of a double Cys mutant of CaM by small-angle X-ray scattering (SAXS) and Fourier transform infrared (FTIR) spectroscopy. The CaM mutant is then used to cross-link poly(ethylene glycol) (PEG) chains, which are bound covalently to a supporting planar Si surface. These films are characterized by X-ray reflectometry (XR) in a humidity chamber providing full hydration. It is well known that Ca2+-saturated holo-CaM binds trifluoperazine (TFP) and changes its conformation from an open, dumbbell-shaped to a closed, globular one in solution. At the interface, we observe an increase of the PEG-CaM film thickness, when TFP is binding and inducing the closed conformation, whereas the removal of Ca2+-ions and a concomitant release of TFP is associated with a decrease of the film thickness. This toggling of the film thickness is largely reversible. In this way, a structural change of the interface is achieved via protein functionality which has the advantage of being selective for ligand molecules without changing the environmental conditions in a harsh way via physico-chemical parameters.
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Affiliation(s)
- Süleyman Cinar
- TU Dortmund University, Department of Chemistry and Chemical Biology, D-44221 Dortmund, Germany
| | - Claus Czeslik
- TU Dortmund University, Department of Chemistry and Chemical Biology, D-44221 Dortmund, Germany.
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30
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Reactive sulfur species inactivate Ca 2+/calmodulin-dependent protein kinase IV via S-polysulfidation of its active-site cysteine residue. Biochem J 2017. [PMID: 28637792 DOI: 10.1042/bcj20170092] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Reactive sulfur species (RSS) modulate protein functions via S-polysulfidation of reactive Cys residues. Here, we report that Ca2+/calmodulin (CaM)-dependent protein kinase IV (CaMKIV) was reversibly inactivated by RSS via polysulfidation of the active-site Cys residue. CaMKIV is phosphorylated at Thr196 by its upstream CaMK kinase (CaMKK), resulting in the induction of its full activity. In vitro incubation of CaMKIV with the exogenous RSS donors Na2S n (n = 2-4) resulted in dose-dependent inhibition of the CaMKK-induced phospho-Thr196 and consequent inactivation of the enzyme activity. Conversely, mutated CaMKIV (C198V) was refractory to the Na2S n -induced enzyme inhibition. A biotin-polyethylene glycol-conjugated maleimide capture assay revealed that Cys198 in CaMKIV represents a target for S-polysulfidation. Furthermore, phosho-Thr196 and CaMKIV activity were inhibited by incubation with cysteine hydropersulfide, a newly identified RSS that is generated from cystine by cystathionine-γ-lyase. In transfected cells expressing CaMKIV, ionomycin-induced CaMKIV phosphorylation at Thr196 was decreased upon treatment with either Na2S4 or the endoplasmic reticulum (ER) stress inducer thapsigargin, whereas cells expressing mutant CaMKIV (C198V) were resistant to this treatment. In addition, the ionomycin-induced phospho-Thr196 of endogenous CaMKIV was also inhibited by treatment either with Na2S4 or thapsigargin in Jurkat T lymphocytes. Taken together, these data define a novel signaling function for intracellular RSS in inhibiting CaMKIV activity via S-polysulfidation of its Cys198 during the response to ER stress.
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31
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Cinar S, Möbitz S, Al-Ayoubi S, Seidlhofer BK, Czeslik C. Building Polyelectrolyte Multilayers with Calmodulin: A Neutron and X-ray Reflectivity Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3982-3990. [PMID: 28379700 DOI: 10.1021/acs.langmuir.7b00651] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We have studied the formation and functional properties of polyelectrolyte multilayers where calmodulin (CaM) is used as a polyanion. CaM is known to populate distinct conformational states upon binding Ca2+ and small ligand molecules. Therefore, we have also probed the effects of Ca2+ ions and trifluoperazine (TFP) as ligand molecule on the interfacial structures. Multilayers with the maximum sequence PEI-(PSS-PAH)x-CaM-PAH-CaM-PAH have been deposited on silicon wafers and characterized by X-ray and neutron reflectometry. From the analysis of all data, several remarkable conclusions can be drawn. When CaM is deposited for the second time, a much thicker sublayer is produced than in the first CaM deposition step. However, upon rinsing with PAH, very thin CaM-PAH sublayers remain. There are no indications that ligand TFP can be involved in the multilayer buildup due to strong CaM-PAH interactions. However, there is a significant increase in the multilayer thickness upon removal of Ca2+ ions from holo-CaM and an equivalent decrease in the multilayer thickness upon subsequent saturation of apo-CaM with Ca2+ ions. Presumably, CaM can still be toggled between an apo and a holo state, when it is embedded in polyelectrolyte multilayers, providing an approach to design bioresponsive interfaces.
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Affiliation(s)
- Süleyman Cinar
- Department of Chemistry and Chemical Biology, TU Dortmund University , D-44221 Dortmund, Germany
| | - Simone Möbitz
- Department of Chemistry and Chemical Biology, TU Dortmund University , D-44221 Dortmund, Germany
| | - Samy Al-Ayoubi
- Department of Chemistry and Chemical Biology, TU Dortmund University , D-44221 Dortmund, Germany
| | | | - Claus Czeslik
- Department of Chemistry and Chemical Biology, TU Dortmund University , D-44221 Dortmund, Germany
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32
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Interactions of in vitro selected fluorogenic peptide aptamers with calmodulin. Biotechnol Lett 2016; 39:375-382. [DOI: 10.1007/s10529-016-2257-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/10/2016] [Indexed: 10/20/2022]
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33
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Ziemba BP, Swisher GH, Masson G, Burke JE, Williams RL, Falke JJ. Regulation of a Coupled MARCKS-PI3K Lipid Kinase Circuit by Calmodulin: Single-Molecule Analysis of a Membrane-Bound Signaling Module. Biochemistry 2016; 55:6395-6405. [PMID: 27933776 DOI: 10.1021/acs.biochem.6b00908] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Amoeboid cells that employ chemotaxis to travel up an attractant gradient possess a signaling network assembled on the leading edge of the plasma membrane that senses the gradient and remodels the actin mesh and cell membrane to drive movement in the appropriate direction. In leukocytes such as macrophages and neutrophils, and perhaps in other amoeboid cells as well, the leading edge network includes a positive feedback loop in which the signaling of multiple pathway components is cooperatively coupled. Cytoplasmic Ca2+ is a recently recognized component of the feedback loop at the leading edge where it stimulates phosphoinositide-3-kinase (PI3K) and the production of its product signaling lipid phosphatidylinositol 3,4,5-trisphosphate (PIP3). A previous study implicated Ca2+-activated protein kinase C (PKC) and the phosphatidylinositol 4,5-bisphosphate (PIP2) binding protein MARCKS as two important players in this signaling, because PKC phosphorylation of MARCKS releases free PIP2 that serves as the membrane binding target and substrate for PI3K. This study asks whether calmodulin (CaM), which is known to directly bind MARCKS, also stimulates PIP3 production by releasing free PIP2. Single-molecule fluorescence microscopy is used to quantify the surface density and enzyme activity of key protein components of the hypothesized Ca2+-CaM-MARCKS-PIP2-PI3K-PIP3 circuit. The findings show that CaM does stimulate PI3K lipid kinase activity by binding MARCKS and displacing it from PIP2 headgroups, thereby releasing free PIP2 that recruits active PI3K to the membrane and serves as the substrate for the generation of PIP3. The resulting CaM-triggered activation of PI3K is complete in seconds and is much faster than PKC-triggered activation, which takes minutes. Overall, the available evidence implicates both PKC and CaM in the coupling of Ca2+ and PIP3 signals and suggests these two different pathways have slow and fast activation kinetics, respectively.
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Affiliation(s)
- Brian P Ziemba
- Molecular Biophysics Program and Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309-0215, United States
| | - G Hayden Swisher
- Molecular Biophysics Program and Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309-0215, United States
| | - Glenn Masson
- Laboratory of Molecular Biology, Medical Research Council , Cambridge CB2 0QH, U.K
| | - John E Burke
- Laboratory of Molecular Biology, Medical Research Council , Cambridge CB2 0QH, U.K
| | - Roger L Williams
- Laboratory of Molecular Biology, Medical Research Council , Cambridge CB2 0QH, U.K
| | - Joseph J Falke
- Molecular Biophysics Program and Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309-0215, United States
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34
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Senga Y, Akizuki K, Katayama S, Shigeri Y, Kameshita I, Ishida A, Sueyoshi N. High-performance CaMKI: A highly active and stable form of CaMKIδ produced by high-level soluble expression in Escherichia coli. Biochem Biophys Res Commun 2016; 475:277-82. [DOI: 10.1016/j.bbrc.2016.05.060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Accepted: 05/11/2016] [Indexed: 10/21/2022]
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35
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Fujiwara Y, Kawaguchi Y, Fujimoto T, Kanayama N, Magari M, Tokumitsu H. Differential AMP-activated Protein Kinase (AMPK) Recognition Mechanism of Ca2+/Calmodulin-dependent Protein Kinase Kinase Isoforms. J Biol Chem 2016; 291:13802-8. [PMID: 27151216 DOI: 10.1074/jbc.m116.727867] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Indexed: 11/06/2022] Open
Abstract
Ca(2+)/calmodulin-dependent protein kinase kinase β (CaMKKβ) is a known activating kinase for AMP-activated protein kinase (AMPK). In vitro, CaMKKβ phosphorylates Thr(172) in the AMPKα subunit more efficiently than CaMKKα, with a lower Km (∼2 μm) for AMPK, whereas the CaMKIα phosphorylation efficiencies by both CaMKKs are indistinguishable. Here we found that subdomain VIII of CaMKK is involved in the discrimination of AMPK as a native substrate by measuring the activities of various CaMKKα/CaMKKβ chimera mutants. Site-directed mutagenesis analysis revealed that Leu(358) in CaMKKβ/Ile(322) in CaMKKα confer, at least in part, a distinct recognition of AMPK but not of CaMKIα.
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Affiliation(s)
- Yuya Fujiwara
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan and
| | - Yoshinori Kawaguchi
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan and
| | | | - Naoki Kanayama
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan and
| | - Masaki Magari
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan and
| | - Hiroshi Tokumitsu
- From the Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan and
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36
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Furuya Y, Denda M, Sakane K, Ogusu T, Takahashi S, Magari M, Kanayama N, Morishita R, Tokumitsu H. Identification of striated muscle activator of Rho signaling (STARS) as a novel calmodulin target by a newly developed genome-wide screen. Cell Calcium 2016; 60:32-40. [PMID: 27132186 DOI: 10.1016/j.ceca.2016.04.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/13/2016] [Accepted: 04/13/2016] [Indexed: 02/07/2023]
Abstract
To search for novel target(s) of the Ca(2+)-signaling transducer, calmodulin (CaM), we performed a newly developed genome-wide CaM interaction screening of 19,676 GST-fused proteins expressed in human. We identified striated muscle activator of Rho signaling (STARS) as a novel CaM target and characterized its CaM binding ability and found that the Ca(2+)/CaM complex interacted stoichiometrically with the N-terminal region (Ala13-Gln35) of STARS in vitro as well as in living cells. Mutagenesis studies identified Ile20 and Trp33 as the essential hydrophobic residues in CaM anchoring. Furthermore, the CaM binding deficient mutant (Ile20Ala, Trp33Ala) of STARS further enhanced its stimulatory effect on SRF-dependent transcriptional activation. These results suggest a connection between Ca(2+)-signaling via excitation-contraction coupling and the regulation of STARS-mediated gene expression in muscles.
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Affiliation(s)
- Yusui Furuya
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Miwako Denda
- CellFree Sciences Co., Ltd., Matsuyama, 790-8577, Japan
| | - Kyohei Sakane
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Tomoko Ogusu
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Sumio Takahashi
- Department of Biology, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Masaki Magari
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Naoki Kanayama
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - Ryo Morishita
- CellFree Sciences Co., Ltd., Matsuyama, 790-8577, Japan
| | - Hiroshi Tokumitsu
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
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37
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The activating role of phospho-(Tyr)-calmodulin on the epidermal growth factor receptor. Biochem J 2015; 472:195-204. [DOI: 10.1042/bj20150851] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/22/2015] [Indexed: 02/06/2023]
Abstract
The existence of a calmodulin (CaM)/phospho-(Tyr)-CaM cycle involved in the regulation of the epidermal growth factor receptor could have important consequences for the control of cell proliferation, as its alteration could potentially result in uncontrolled tumour growth.
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Human adenosine A2A receptor binds calmodulin with high affinity in a calcium-dependent manner. Biophys J 2015; 108:903-917. [PMID: 25692595 DOI: 10.1016/j.bpj.2014.12.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 12/02/2014] [Accepted: 12/16/2014] [Indexed: 12/22/2022] Open
Abstract
Understanding how ligands bind to G-protein-coupled receptors and how binding changes receptor structure to affect signaling is critical for developing a complete picture of the signal transduction process. The adenosine A2A receptor (A2AR) is a particularly interesting example, as it has an exceptionally long intracellular carboxyl terminus, which is predicted to be mainly disordered. Experimental data on the structure of the A2AR C-terminus is lacking, because published structures of A2AR do not include the C-terminus. Calmodulin has been reported to bind to the A2AR C-terminus, with a possible binding site on helix 8, next to the membrane. The biological meaning of the interaction as well as its calcium dependence, thermodynamic parameters, and organization of the proteins in the complex are unclear. Here, we characterized the structure of the A2AR C-terminus and the A2AR C-terminus-calmodulin complex using different biophysical methods, including native gel and analytical gel filtration, isothermal titration calorimetry, NMR spectroscopy, and small-angle X-ray scattering. We found that the C-terminus is disordered and flexible, and it binds with high affinity (Kd = 98 nM) to calmodulin without major conformational changes in the domain. Calmodulin binds to helix 8 of the A2AR in a calcium-dependent manner that can displace binding of A2AR to lipid vesicles. We also predicted and classified putative calmodulin-binding sites in a larger group of G-protein-coupled receptors.
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Onouchi T, Kishino-Kaneko Y, Kameshita I, Ishida A, Sueyoshi N. Regulation of Ca(2+)/calmodulin-dependent protein kinase phosphatase (CaMKP/PPM1F) by protocadherin-γC5 (Pcdh-γC5). Arch Biochem Biophys 2015; 585:109-120. [PMID: 26386307 DOI: 10.1016/j.abb.2015.09.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/15/2015] [Accepted: 09/15/2015] [Indexed: 01/14/2023]
Abstract
Ca(2+)/calmodulin-dependent protein kinase phosphatase (CaMKP/PPM1F) is a Ser/Thr protein phosphatase that belongs to the PPM family. It is important to identify an endogenous regulator of CaMKP. Using an Escherichia coli two-hybrid screening method, we identified the C-terminal cytoplasmic fragment of protocadherin γ subfamily C5 (Pcdh-γC5), which was generated by intracellular processing, as a CaMKP-binding protein. Dephosphorylation of phosphorylated Ca(2+)/calmodulin-dependent protein kinase I (CaMKI) by CaMKP was significantly activated by the C-terminal cytoplasmic fragment, Pcdh-γC5(715-944), both in vitro and in cells, suggesting that the C-terminal fragment functions as an endogenous activator of CaMKP. The nuclear translocation of the fragment was blocked by its binding to cytoplasmic CaMKP to form a ternary complex with CaMKI. Taken together, these results strongly suggest that the C-terminal cytoplasmic fragment of Pcdh-γC5 acts as a scaffold for CaMKP and CaMKI to regulate CaMKP activity. These findings may provide new insights into the reversible regulation of CaMKP in cells.
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Affiliation(s)
- Takashi Onouchi
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa 761-0795, Japan
| | - Yoshimi Kishino-Kaneko
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa 761-0795, Japan
| | - Isamu Kameshita
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa 761-0795, Japan
| | - Atsuhiko Ishida
- Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan.
| | - Noriyuki Sueyoshi
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa 761-0795, Japan.
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40
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Fujiwara Y, Hiraoka Y, Fujimoto T, Kanayama N, Magari M, Tokumitsu H. Analysis of Distinct Roles of CaMKK Isoforms Using STO-609-Resistant Mutants in Living Cells. Biochemistry 2015; 54:3969-77. [DOI: 10.1021/acs.biochem.5b00149] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuya Fujiwara
- Division
of Medical Bioengineering, Graduate School of Natural Science and
Technology, Okayama University, Okayama 700-8530, Japan
| | - Yuri Hiraoka
- Division
of Medical Bioengineering, Graduate School of Natural Science and
Technology, Okayama University, Okayama 700-8530, Japan
| | | | - Naoki Kanayama
- Division
of Medical Bioengineering, Graduate School of Natural Science and
Technology, Okayama University, Okayama 700-8530, Japan
| | - Masaki Magari
- Division
of Medical Bioengineering, Graduate School of Natural Science and
Technology, Okayama University, Okayama 700-8530, Japan
| | - Hiroshi Tokumitsu
- Division
of Medical Bioengineering, Graduate School of Natural Science and
Technology, Okayama University, Okayama 700-8530, Japan
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41
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The Phosphatase-Resistant Isoform of CaMKI, Ca²⁺/Calmodulin-Dependent Protein Kinase Iδ (CaMKIδ), Remains in Its "Primed" Form without Ca²⁺ Stimulation. Biochemistry 2015; 54:3617-30. [PMID: 25994484 DOI: 10.1021/bi5012139] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ca²⁺/calmodulin-dependent protein kinase I (CaMKI) is known to play pivotal roles in Ca²⁺ signaling pathways. Four isoforms of CaMKI (α, β, γ, and δ) have been reported so far. CaMKI is activated through phosphorylation by the upstream kinase, CaMK kinase (CaMKK), and phosphorylates downstream targets. When CaMKI was transiently expressed in 293T cells, CaMKIα was not phosphorylated at all under low-Ca²⁺ conditions in the cells. In contrast, we found that CaMKIδ was significantly phosphorylated and activated to phosphorylate cAMP response element-binding protein (CREB) under the same conditions. Herein, we report that the sustained activation of CaMKIδ is ascribed to its phosphatase resistance resulting from the structure of its N-terminal region. First, we examined whether CaMKIδ is more readily phosphorylated by CaMKK than CaMKIα, but no significant difference was observed. Next, to compare the phosphatase resistance between CaMKIα and CaMKIδ, we assessed the dephosphorylation of the phosphorylated CaMKIs by CaMK phosphatase (CaMKP/PPM1F). Surprisingly, CaMKIδ was hardly dephosphorylated by CaMKP, whereas CaMKIα was significantly dephosphorylated under the same conditions. To date, there have been no detailed reports concerning dephosphorylation of CaMKI. Through extensive analysis of CaMKP-catalyzed dephosphorylation of various chimeric and point mutants of CaMKIδ and CaMKIα, we identified the amino acid residues responsible for the phosphatase resistance of CaMKIδ (Pro-57, Lys-62, Ser-66, Ile-68, and Arg-76). These results also indicate that the phosphatase resistance of CaMKI is largely affected by only several amino acids in its N-terminal region. The phosphatase-resistant CaMKI isoform may play a physiological role under low-Ca²⁺ conditions in the cells.
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Kobayashi Y, da Silva R, Kumanogoh H, Miyata S, Sato C, Kitajima K, Nakamura S, Morita M, Hayashi F, Maekawa S. Ganglioside contained in the neuronal tissue-enriched acidic protein of 22 kDa (NAP-22) fraction prepared from the detergent-resistant membrane microdomain of rat brain inhibits the phosphatase activity of calcineurin. J Neurosci Res 2015; 93:1462-70. [PMID: 25981177 DOI: 10.1002/jnr.23599] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 11/05/2022]
Abstract
Neurons have well-developed membrane microdomains called "rafts" that are recovered as a detergent-resistant membrane microdomain fraction (DRM). Neuronal tissue-enriched acidic protein of 22 kDa (NAP-22) is one of the major protein components of neuronal DRM. To determine the cellular function of NAP-22, interacting proteins were screened with an immunoprecipitation assay, and calcineurin (CaN) was detected. Further studies with NAP-22 prepared from DRM and CaN expressed in bacteria showed the binding of these proteins and a dose-dependent inhibitory effect of the NAP-22 fraction on the phosphatase activity of CaN. On the other hand, NAP-22 expressed in bacteria showed low binding to CaN and a weak inhibitory effect on phosphatase activity. To solve this discrepancy, identification of a nonprotein component that modulates CaN activity in the DRM-derived NAP-22 fraction was attempted. After lyophilization, a lipid fraction was extracted with chloroform/methanol. The lipid fraction showed an inhibitory effect on CaN without NAP-22, and further fractionation of the extract with thin-layer chromatography showed the presence of several lipid bands having an inhibitory effect on CaN. The mobility of these bands coincided with that of authentic ganglioside (GM1a, GD1a, GD1b, and GT1b), and authentic ganglioside showed an inhibitory effect on CaN. Treatment of lipid with endoglycoceramidase, which degrades ganglioside to glycochain and ceramide, caused a diminution of the inhibitory effect. These results show that DRM-derived NAP-22 binds several lipids, including ganglioside, and that ganglioside inhibits the phosphatase activity of CaN.
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Affiliation(s)
- Yuumi Kobayashi
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Ronan da Silva
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Haruko Kumanogoh
- Division of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Shinji Miyata
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | - Chihiro Sato
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | - Ken Kitajima
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | - Shun Nakamura
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Japan
| | - Mistuhiro Morita
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Fumio Hayashi
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Shohei Maekawa
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
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43
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Fu C, Zhang J, Zheng Y, Xu H, Yu S. Binding of calmodulin changes the calcineurin regulatory region to a less dynamic conformation. Int J Biol Macromol 2015; 79:235-9. [PMID: 25956027 DOI: 10.1016/j.ijbiomac.2015.04.069] [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: 04/02/2015] [Revised: 04/28/2015] [Accepted: 04/29/2015] [Indexed: 12/24/2022]
Abstract
Calcineurin (CN) is a Ca(2+)/calmodulin (CaM) activated serine/threonine phosphatase, and its regulatory region (CNRR) plays a critical role in the coupling of Ca(2+) signals to cellular responses. Ca(2+)/CaM binds to the CNRR, resulting in a conformational change that removes an autoinhibitory domain (CN467-486) from the active site of the phosphatase and activates the enzyme. However, almost the entire regulatory region (CN374-521) is not visible in the electron density maps of reported structures. In this study, we produced separate CN fragments corresponding to the CNRR (CNRR381-521, CN residues 381-521) and determined the binding affinity of CNRR381-521 for Ca(2+)/CaM using isothermal titration calorimetry (ITC). The structural change in CNRR381-521 induced by Ca(2+)/CaM binding was also investigated by Fourier transform infrared spectroscopy (FT-IR). The results indicate that Ca(2+)/CaM binding to CNRR381-521 is an exothermic reaction with a dissociation constant of 2.0×10(-6) M. Binding of calmodulin changes the calcineurin regulatory region to a less dynamic conformation.
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Affiliation(s)
- Cuiping Fu
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Junting Zhang
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Ye Zheng
- Shanghai Pinghe Bilingual School, China
| | - Hongbing Xu
- Department of Clinical Pharmacy, Shanghai First People's Hospital, Shanghai Jiaotong University, Shanghai 200080, China.
| | - Shaoning Yu
- Department of Chemistry, Fudan University, Shanghai 200433, China.
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44
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Stateva SR, Salas V, Benaim G, Menéndez M, Solís D, Villalobo A. Characterization of phospho-(tyrosine)-mimetic calmodulin mutants. PLoS One 2015; 10:e0120798. [PMID: 25830911 PMCID: PMC4382182 DOI: 10.1371/journal.pone.0120798] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 02/06/2015] [Indexed: 11/18/2022] Open
Abstract
Calmodulin (CaM) phosphorylated at different serine/threonine and tyrosine residues is known to exert differential regulatory effects on a variety of CaM-binding enzymes as compared to non-phosphorylated CaM. In this report we describe the preparation and characterization of a series of phospho-(Y)-mimetic CaM mutants in which either one or the two tyrosine residues present in CaM (Y99 and Y138) were substituted to aspartic acid or glutamic acid. It was expected that the negative charge of the respective carboxyl group of these amino acids mimics the negative charge of phosphate and reproduce the effects that distinct phospho-(Y)-CaM species may have on target proteins. We describe some physicochemical properties of these CaM mutants as compared to wild type CaM, after their expression in Escherichia coli and purification to homogeneity, including: i) changes in their electrophoretic mobility in the absence and presence of Ca2+; ii) ultraviolet (UV) light absorption spectra, far- and near-UV circular dichroism data; iii) thermal stability in the absence and presence of Ca2+; and iv) Tb3+-emitted fluorescence upon tyrosine excitation. We also describe some biochemical properties of these CaM mutants, such as their differential phosphorylation by the tyrosine kinase c-Src, and their action as compared to wild type CaM, on the activity of two CaM-dependent enzymes: cyclic nucleotide phosphodiesterase 1 (PDE1) and endothelial nitric oxide synthase (eNOS) assayed in vitro.
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Affiliation(s)
- Silviya R. Stateva
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Valentina Salas
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
- Universidad Central de Venezuela, Facultad de Ciencias, Instituto de Biología Experimental, Caracas, Venezuela
| | - Gustavo Benaim
- Universidad Central de Venezuela, Facultad de Ciencias, Instituto de Biología Experimental, Caracas, Venezuela
- Instituto de Estudios Avanzados (IDEA), Caracas, Venezuela
| | - Margarita Menéndez
- Instituto de Química Física Rocasolano, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Dolores Solís
- Instituto de Química Física Rocasolano, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Antonio Villalobo
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
- * E-mail:
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45
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The unexpected role of polyubiquitin chains in the formation of fibrillar aggregates. Nat Commun 2015; 6:6116. [PMID: 25600778 PMCID: PMC4309437 DOI: 10.1038/ncomms7116] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 12/18/2014] [Indexed: 12/16/2022] Open
Abstract
Ubiquitin is known to be one of the most soluble and stably folded intracellular proteins, but it is often found in inclusion bodies associated with various diseases including neurodegenerative disorders and cancer. To gain insight into this contradictory behaviour, we have examined the physicochemical properties of ubiquitin and its polymeric chains that lead to aggregate formation. We find that the folding stability of ubiquitin chains unexpectedly decreases with increasing chain length, resulting in the formation of amyloid-like fibrils. Furthermore, when expressed in cells, polyubiquitin chains covalently linked to EGFP also form aggregates depending on chain length. Notably, these aggregates are selectively degraded by autophagy. We propose a novel model in which the physical and chemical instability of polyubiquitin chains drives the formation of fibrils, which then serve as an initiation signal for autophagy.
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46
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A new calmodulin-binding motif for inositol 1,4,5-trisphosphate 3-kinase regulation. Biochem J 2014; 463:319-28. [DOI: 10.1042/bj20140757] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Inositol 1,4,5-trisphosphate 3-kinase regulation by Ca2+/calmodulin involves multiple protein–protein interactions, which form a highly hydrophobic interface and defines a new calmodulin-binding motif. The structural data support that calmodulin binds to an autoinhibitory segment facilitating the kinase activity.
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47
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Kopanic JL, Al-mugotir MH, Kieken F, Zach S, Trease AJ, Sorgen PL. Characterization of the connexin45 carboxyl-terminal domain structure and interactions with molecular partners. Biophys J 2014; 106:2184-95. [PMID: 24853747 PMCID: PMC4052358 DOI: 10.1016/j.bpj.2014.03.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 03/19/2014] [Accepted: 03/31/2014] [Indexed: 02/02/2023] Open
Abstract
Mechanisms underlying the initiation and persistence of lethal cardiac rhythms are of significant clinical and scientific interests. Gap junctions are principally involved in forming the electrical connections between myocytes, and changes in distribution, density, and properties are consistent characteristics in arrhythmic heart disease. Therefore, understanding the structure and function of gap junctions during normal and abnormal impulse propagation are essential in the control of arrhythmias. For example, Cx45 is predominately expressed in the specialized myocytes of the impulse generation and conduction system. In both ventricular and atrial human working myocytes, Cx45 is present in very low quantities. However, a reduction in Cx43 coupled with an increased Cx45 protein levels within the ventricles have been observed after myocardial infarction and end-stage heart failure. Cx45 may influence electrical and/or metabolic coupling as a result of pathophysiological overexpression. Our goal was to identify mechanisms that could cause cellular coupling to be different between the cardiac connexins. Based upon the conserved transmembrane and extracellular loop segments, our focus was on identifying features within the divergent cytoplasmic portions. Here, we biophysically characterize the carboxyl-terminal domain of Cx45 (Cx45CT). Purification revealed the possibility of oligomeric species, which was confirmed by analytical ultracentrifugation experiments. Sedimentation equilibrium and circular dichroism studies of different Cx45CT constructs identified one region of α-helical structure (A333-N361) that mediates CT dimerization through hydrophobic contacts. Interestingly, the binding affinity of Cx45CT dimerization is 1000-fold stronger than Cx43CT dimerization. Cx45CT resonance assignments were also used to identify the binding sites and affinities of molecular partners involved in the Cx45 regulation; although none disrupted dimerization, many of these proteins interacted within one intrinsically disordered region (P278-P285). This domain has similarities with other cardiac connexins, and we propose they constitute a master regulatory domain, which contains overlapping molecular partner binding, cis-trans proline isomerization, and phosphorylation sites.
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Affiliation(s)
- Jennifer L Kopanic
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Mona H Al-mugotir
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Fabien Kieken
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Sydney Zach
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Andrew J Trease
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Paul L Sorgen
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska.
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48
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Kaneko K, Tabuchi M, Sueyoshi N, Ishida A, Utsumi T, Kameshita I. Cellular localization of CoPK12, a Ca(2+)/calmodulin-dependent protein kinase in mushroom Coprinopsis cinerea, is regulated by N-myristoylation. J Biochem 2014; 156:51-61. [PMID: 24659342 DOI: 10.1093/jb/mvu018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Multifunctional Ca(2+)/calmodulin-dependent protein kinases (CaMKs) have been extensively studied in mammals, whereas fungus CaMKs still remain largely uncharacterized. We previously obtained CaMK homolog in Coprinopsis cinerea, designated CoPK12, and revealed its unique catalytic properties in comparison with the mammalian CaMKs. To further clarify the regulatory mechanisms of CoPK12, we investigated post-translational modification and subcellular localization of CoPK12 in this study. In C. cinerea, full-length CoPK12 (65 kDa) was fractionated in the membrane fraction, while the catalytically active fragment (46 kDa) of CoPK12 was solely detected in the soluble fraction by differential centrifugation. Expressed CoPK12-GFP was localized on the cytoplasmic and vacuolar membranes as visualized by green fluorescence in yeast cells. In vitro N-myristoylation assay revealed that CoPK12 is N-myristoylated at Gly-2 in the N-terminal position. Furthermore, calmodulin could bind not only to CaM-binding domain but also to the N-terminal myristoyl moiety of CoPK12. These results, taken together, suggest that the cellular localization and function of CoPK12 are regulated by protein N-myristoylation and limited proteolysis.
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Affiliation(s)
- Keisuke Kaneko
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-Cho, Kagawa 761-0795; Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521; and Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Mitsuaki Tabuchi
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-Cho, Kagawa 761-0795; Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521; and Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Noriyuki Sueyoshi
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-Cho, Kagawa 761-0795; Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521; and Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Atsuhiko Ishida
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-Cho, Kagawa 761-0795; Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521; and Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Toshihiko Utsumi
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-Cho, Kagawa 761-0795; Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521; and Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Isamu Kameshita
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-Cho, Kagawa 761-0795; Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521; and Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
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49
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Zhao Y, Yang H, Meng K, Yu S. Probing the Ca2+/CaM-induced secondary structural and conformational changes in calcineurin. Int J Biol Macromol 2014; 64:453-7. [DOI: 10.1016/j.ijbiomac.2013.12.036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 12/24/2013] [Accepted: 12/27/2013] [Indexed: 10/25/2022]
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50
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Alaimo A, Alberdi A, Gomis-Perez C, Fernández-Orth J, Bernardo-Seisdedos G, Malo C, Millet O, Areso P, Villarroel A. Pivoting between calmodulin lobes triggered by calcium in the Kv7.2/calmodulin complex. PLoS One 2014; 9:e86711. [PMID: 24489773 PMCID: PMC3904923 DOI: 10.1371/journal.pone.0086711] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/12/2013] [Indexed: 11/25/2022] Open
Abstract
Kv7.2 (KCNQ2) is the principal molecular component of the slow voltage gated M-channel, which strongly influences neuronal excitability. Calmodulin (CaM) binds to two intracellular C-terminal segments of Kv7.2 channels, helices A and B, and it is required for exit from the endoplasmic reticulum. However, the molecular mechanisms by which CaM controls channel trafficking are currently unknown. Here we used two complementary approaches to explore the molecular events underlying the association between CaM and Kv7.2 and their regulation by Ca2+. First, we performed a fluorometric assay using dansylated calmodulin (D-CaM) to characterize the interaction of its individual lobes to the Kv7.2 CaM binding site (Q2AB). Second, we explored the association of Q2AB with CaM by NMR spectroscopy, using 15N-labeled CaM as a reporter. The combined data highlight the interdependency of the N- and C-lobes of CaM in the interaction with Q2AB, suggesting that when CaM binds Ca2+ the binding interface pivots between the N-lobe whose interactions are dominated by helix B and the C-lobe where the predominant interaction is with helix A. In addition, Ca2+ makes CaM binding to Q2AB more difficult and, reciprocally, the channel weakens the association of CaM with Ca2+.
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Affiliation(s)
- Alessandro Alaimo
- Unidad de Biofísica, CSIC, UPV/EHU, Universidad del País Vasco, Leioa, Spain
| | - Araitz Alberdi
- Unidad de Biofísica, CSIC, UPV/EHU, Universidad del País Vasco, Leioa, Spain
| | | | | | | | - Covadonga Malo
- Unidad de Biofísica, CSIC, UPV/EHU, Universidad del País Vasco, Leioa, Spain
| | - Oscar Millet
- Structural Biology Unit, CICbioGUNE, Bizkaia Technology Park, Derio, Spain
| | - Pilar Areso
- Departamento de Farmacología, UPV/EHU, Universidad del País Vasco, Leioa, Spain
| | - Alvaro Villarroel
- Unidad de Biofísica, CSIC, UPV/EHU, Universidad del País Vasco, Leioa, Spain
- * E-mail:
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