1
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Fenwick M, Reers AR, Liu Y, Zigweid R, Sankaran B, Shin J, Hulverson MA, Hammerson B, Fernández Álvaro E, Myler PJ, Kaushansky A, Van Voorhis WC, Fan E, Staker BL. Identification of and Structural Insights into Hit Compounds Targeting N-Myristoyltransferase for Cryptosporidium Drug Development. ACS Infect Dis 2023; 9:1821-1833. [PMID: 37722671 PMCID: PMC10580320 DOI: 10.1021/acsinfecdis.3c00151] [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: 03/29/2023] [Indexed: 09/20/2023]
Abstract
Each year, approximately 50,000 children under 5 die as a result of diarrhea caused by Cryptosporidium parvum, a protozoan parasite. There are currently no effective drugs or vaccines available to cure or prevent Cryptosporidium infection, and there are limited tools for identifying and validating targets for drug or vaccine development. We previously reported a high throughput screening (HTS) of a large compound library against Plasmodium N-myristoyltransferase (NMT), a validated drug target in multiple protozoan parasite species. To identify molecules that could be effective against Cryptosporidium, we counter-screened hits from the Plasmodium NMT HTS against Cryptosporidium NMT. We identified two potential hit compounds and validated them against CpNMT to determine if NMT might be an attractive drug target also for Cryptosporidium. We tested the compounds against Cryptosporidium using both cell-based and NMT enzymatic assays. We then determined the crystal structure of CpNMT bound to Myristoyl-Coenzyme A (MyrCoA) and structures of ternary complexes with MyrCoA and the hit compounds to identify the ligand binding modes. The binding site architectures display different conformational states in the presence of the two inhibitors and provide a basis for rational design of selective inhibitors.
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Affiliation(s)
- Michael
K. Fenwick
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
| | - Alexandra R. Reers
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
| | - Yi Liu
- Department
of Biochemistry, University of Washington, Seattle, Washington 98195, United States
| | - Rachael Zigweid
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
| | - Banumathi Sankaran
- Berkeley
Center for Structural Biology, Advanced Light Source, Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Janis Shin
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
| | - Matthew A. Hulverson
- Center
for Emerging and Re-emerging Infectious Diseases, Division of Allergy
and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington 98109, United States
| | - Bradley Hammerson
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
| | | | - Peter J. Myler
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
- Department
of Global Health, University of Washington, Seattle, Washington 98195, United States
- Department
of Pediatrics, University of Washington, Seattle, Washington 98195, United States
| | - Alexis Kaushansky
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
- Center
for Emerging and Re-emerging Infectious Diseases, Division of Allergy
and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington 98109, United States
- Department
of Global Health, University of Washington, Seattle, Washington 98195, United States
| | - Wesley C. Van Voorhis
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center
for Emerging and Re-emerging Infectious Diseases, Division of Allergy
and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington 98109, United States
| | - Erkang Fan
- Department
of Biochemistry, University of Washington, Seattle, Washington 98195, United States
| | - Bart L. Staker
- Seattle
Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington 98109, United States
- Center
for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98109, United States
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2
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Pedretti M, Favretto F, Troilo F, Giovannoni M, Conter C, Mattei B, Dominici P, Travaglini-Allocatelli C, Di Matteo A, Astegno A. Role of myristoylation in modulating PCaP1 interaction with calmodulin. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 203:108003. [PMID: 37717348 DOI: 10.1016/j.plaphy.2023.108003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 08/09/2023] [Accepted: 09/04/2023] [Indexed: 09/19/2023]
Abstract
Plasma membrane-associated Cation-binding Protein 1 (PCaP1) belongs to the plant-unique DREPP protein family with largely unknown biological functions but ascertained roles in plant development and calcium (Ca2+) signaling. PCaP1 is anchored to the plasma membrane via N-myristoylation and a polybasic cluster, and its N-terminal region can bind Ca2+/calmodulin (CaM). However, the molecular determinants of PCaP1-Ca2+-CaM interaction and the functional impact of myristoylation in the complex formation and Ca2+ sensitivity of CaM remained to be elucidated. Herein, we investigated the direct interaction between Arabidopsis PCaP1 (AtPCaP1) and CaM1 (AtCaM1) using both myristoylated and non-myristoylated peptides corresponding to the N-terminal region of AtPCaP1. ITC analysis showed that AtCaM1 forms a high affinity 1:1 complex with AtPCaP1 peptides and the interaction is strictly Ca2+-dependent. Spectroscopic and kinetic Ca2+ binding studies showed that the myristoylated peptide dramatically increased the Ca2+-binding affinity of AtCaM1 and slowed the Ca2+ dissociation rates from both the C- and N-lobes, thus suggesting that the myristoylation modulates the mechanism of AtPCaP1 recognition by AtCaM1. Furthermore, NMR and CD spectroscopy revealed that the structure of both the N- and C-lobes of Ca2+-AtCaM1 changes markedly in the presence of the myristoylated AtPCaP1 peptide, which assumes a helical structure in the final complex. Overall, our results indicate that AtPCaP1 biological function is strictly related to the presence of multiple ligands, i.e., the myristoyl moiety, Ca2+ ions and AtCaM1 and only a full characterization of their equilibria will allow for a complete molecular understanding of the putative role of PCaP1 as signal protein.
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Affiliation(s)
- Marco Pedretti
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | - Filippo Favretto
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | - Francesca Troilo
- CNR Institute of Molecular Biology and Pathology, P.le Aldo Moro 5, 00185, Rome, Italy
| | - Moira Giovannoni
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100, L'Aquila, Italy
| | - Carolina Conter
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | - Benedetta Mattei
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100, L'Aquila, Italy
| | - Paola Dominici
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | | | - Adele Di Matteo
- CNR Institute of Molecular Biology and Pathology, P.le Aldo Moro 5, 00185, Rome, Italy.
| | - Alessandra Astegno
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
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3
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Rodríguez-Hernández D, Vijayan K, Zigweid R, Fenwick MK, Sankaran B, Roobsoong W, Sattabongkot J, Glennon EKK, Myler PJ, Sunnerhagen P, Staker BL, Kaushansky A, Grøtli M. Identification of potent and selective N-myristoyltransferase inhibitors of Plasmodium vivax liver stage hypnozoites and schizonts. Nat Commun 2023; 14:5408. [PMID: 37669940 PMCID: PMC10480161 DOI: 10.1038/s41467-023-41119-7] [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: 04/07/2023] [Accepted: 08/22/2023] [Indexed: 09/07/2023] Open
Abstract
Drugs targeting multiple stages of the Plasmodium vivax life cycle are needed to reduce the health and economic burdens caused by malaria worldwide. N-myristoyltransferase (NMT) is an essential eukaryotic enzyme and a validated drug target for combating malaria. However, previous PvNMT inhibitors have failed due to their low selectivity over human NMTs. Herein, we apply a structure-guided hybridization approach combining chemical moieties of previously reported NMT inhibitors to develop the next generation of PvNMT inhibitors. A high-resolution crystal structure of PvNMT bound to a representative selective hybrid compound reveals a unique binding site architecture that includes a selective conformation of a key tyrosine residue. The hybridized compounds significantly decrease P. falciparum blood-stage parasite load and consistently exhibit dose-dependent inhibition of P. vivax liver stage schizonts and hypnozoites. Our data demonstrate that hybridized NMT inhibitors can be multistage antimalarials, targeting dormant and developing forms of liver and blood stage.
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Affiliation(s)
- Diego Rodríguez-Hernández
- Department of Chemistry and Molecular Biology, University of Gothenburg; S-405 30, Gothenburg, Sweden
- Department of Chemistry, University of Bergen, Allegaten 41, NO-5007, Bergen, Norway
| | - Kamalakannan Vijayan
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, 98109, USA
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, 695551, India
| | - Rachael Zigweid
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, 98109, USA
- Seattle Structural Genomics Center for Infectious Disease, Seattle, WA, 98109, USA
| | - Michael K Fenwick
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, 98109, USA
- Seattle Structural Genomics Center for Infectious Disease, Seattle, WA, 98109, USA
| | - Banumathi Sankaran
- Molecular Biophysics and Integrated Bioimaging, Berkeley Center for Structural Biology, Advanced Light Source; Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Wanlapa Roobsoong
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Elizabeth K K Glennon
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, 98109, USA
| | - Peter J Myler
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, 98109, USA
- Seattle Structural Genomics Center for Infectious Disease, Seattle, WA, 98109, USA
- Department of Pediatrics, University of Washington, Seattle, WA, 98195, USA
| | - Per Sunnerhagen
- Department of Chemistry and Molecular Biology, University of Gothenburg; S-405 30, Gothenburg, Sweden
| | - Bart L Staker
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, 98109, USA
- Seattle Structural Genomics Center for Infectious Disease, Seattle, WA, 98109, USA
| | - Alexis Kaushansky
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, 98109, USA.
- Department of Pediatrics, University of Washington, Seattle, WA, 98195, USA.
| | - Morten Grøtli
- Department of Chemistry and Molecular Biology, University of Gothenburg; S-405 30, Gothenburg, Sweden.
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4
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Hanashima S, Mito K, Umegawa Y, Murata M, Hojo H. Lipid chain-driven interaction of a lipidated Src-family kinase Lyn with the bilayer membrane. Org Biomol Chem 2022; 20:6436-6444. [PMID: 35880995 DOI: 10.1039/d2ob01079h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
N-Myristoylation is a process of ubiquitous protein modification, which promotes the interaction of lipidated proteins on cell surfaces, in conjunction with reversible S-palmitoylation. We report the cooperative lipid-lipid interaction of two acyl chains of proteins, which increases the protein-membrane interaction and facilitates selective targeting of membranes containing anionic lipids. Lyn is a member of the Src family kinases distributed on the membrane surface by N-myristoyl and neighbouring S-palmitoyl chain anchors at the unique N-terminus domain. We prepared N-terminal short segments of lipidated Lyn to investigate the behaviour of each acyl chain in the lipid composition-dependent membrane interaction by solid-state nuclear magnetic resonance (NMR) analysis. Solid-state 31P-NMR studies revealed that S-palmitoylation of N-myristoylated Lyn peptides increased the interaction between peptides and phospholipid head groups, particularly with the anionic phosphatidylserine-containing bilayers. The solid-state 2H-NMR of Lyn peptides with a perdeutero N-myristoyl chain indicated an increase (0.6-0.8 Å) in the extent of the N-myristoyl chain in the presence of nearby S-palmitoyl chains, probably through the interaction via the acyl chains. The cooperative hydrocarbon chain interaction of the two acyl chains of Lyn increased membrane binding by extending the hydrocarbon chains deeper into the membrane interior, thereby promoting the peptide-membrane surface interaction between the cationic peptide side chains and the anionic lipid head groups. This lipid-driven mechanism by S-palmitoylation promotes the partition of the lipidated proteins to the cytoplasmic surface of the cell membranes and may be involved in recruiting Lyn at the signalling domains rich in anionic lipids.
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Affiliation(s)
- Shinya Hanashima
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
| | - Kanako Mito
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
| | - Yuichi Umegawa
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan. .,Forefront Research Center, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Hironobu Hojo
- Forefront Research Center, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.,Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita 565-0871, Japan
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5
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A high-affinity cocaine binding site associated with the brain acid soluble protein 1. Proc Natl Acad Sci U S A 2022; 119:e2200545119. [PMID: 35412917 PMCID: PMC9169839 DOI: 10.1073/pnas.2200545119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Cocaine is a monoamine transport inhibitor. Current models attributing pharmacologic actions of cocaine to inhibiting the activity of the amine transporters alone failed to translate to the clinic. Cocaine inhibition of the dopamine, serotonin, and norepinephrine transporters is relatively weak, suggesting that blockade of the amine transporters alone cannot account for the actions of cocaine, especially at low doses. There is evidence for significantly more potent actions of cocaine, suggesting the existence of a high-affinity receptor(s) for the drug. Identifying and characterizing such receptors will deepen our understanding of cocaine pharmacologic actions and pave the way for therapeutic development. Here we identify a high-affinity cocaine binding site associated with BASP1 that is involved in mediating the drug’s psychotropic actions. Cocaine exerts its stimulant effect by inhibiting dopamine (DA) reuptake, leading to increased dopamine signaling. This action is thought to reflect the binding of cocaine to the dopamine transporter (DAT) to inhibit its function. However, cocaine is a relatively weak inhibitor of DAT, and many DAT inhibitors do not share cocaine’s behavioral actions. Further, recent reports show more potent actions of the drug, implying the existence of a high-affinity receptor for cocaine. We now report high-affinity binding of cocaine associated with the brain acid soluble protein 1 (BASP1) with a dissociation constant (Kd) of 7 nM. Knocking down BASP1 in the striatum inhibits [3H]cocaine binding to striatal synaptosomes. Depleting BASP1 in the nucleus accumbens but not the dorsal striatum diminishes locomotor stimulation in mice. Our findings imply that BASP1 is a pharmacologically relevant receptor for cocaine.
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6
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Li W, Li F, Zhang X, Lin HK, Xu C. Insights into the post-translational modification and its emerging role in shaping the tumor microenvironment. Signal Transduct Target Ther 2021; 6:422. [PMID: 34924561 PMCID: PMC8685280 DOI: 10.1038/s41392-021-00825-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 11/02/2021] [Accepted: 11/05/2021] [Indexed: 12/11/2022] Open
Abstract
More and more in-depth studies have revealed that the occurrence and development of tumors depend on gene mutation and tumor heterogeneity. The most important manifestation of tumor heterogeneity is the dynamic change of tumor microenvironment (TME) heterogeneity. This depends not only on the tumor cells themselves in the microenvironment where the infiltrating immune cells and matrix together forming an antitumor and/or pro-tumor network. TME has resulted in novel therapeutic interventions as a place beyond tumor beds. The malignant cancer cells, tumor infiltrate immune cells, angiogenic vascular cells, lymphatic endothelial cells, cancer-associated fibroblastic cells, and the released factors including intracellular metabolites, hormonal signals and inflammatory mediators all contribute actively to cancer progression. Protein post-translational modification (PTM) is often regarded as a degradative mechanism in protein destruction or turnover to maintain physiological homeostasis. Advances in quantitative transcriptomics, proteomics, and nuclease-based gene editing are now paving the global ways for exploring PTMs. In this review, we focus on recent developments in the PTM area and speculate on their importance as a critical functional readout for the regulation of TME. A wealth of information has been emerging to prove useful in the search for conventional therapies and the development of global therapeutic strategies.
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Affiliation(s)
- Wen Li
- grid.54549.390000 0004 0369 4060Integrative Cancer Center & Cancer Clinical Research Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610042 Chengdu, P. R. China
| | - Feifei Li
- grid.54549.390000 0004 0369 4060Integrative Cancer Center & Cancer Clinical Research Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610042 Chengdu, P. R. China ,grid.256607.00000 0004 1798 2653Guangxi Collaborative Innovation Center for Biomedicine (Guangxi-ASEAN Collaborative Innovation Center for Major Disease Prevention and Treatment), Guangxi Medical University, 530021 Nanning, Guangxi China
| | - Xia Zhang
- grid.410570.70000 0004 1760 6682Institute of Pathology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Hui-Kuan Lin
- grid.241167.70000 0001 2185 3318Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston Salem, NC 27101 USA
| | - Chuan Xu
- Integrative Cancer Center & Cancer Clinical Research Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, 610042, Chengdu, P. R. China. .,Department of Cancer Biology, Wake Forest Baptist Medical Center, Wake Forest University, Winston Salem, NC, 27101, USA.
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7
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Chung D, Shum A, Caraveo G. GAP-43 and BASP1 in Axon Regeneration: Implications for the Treatment of Neurodegenerative Diseases. Front Cell Dev Biol 2020; 8:567537. [PMID: 33015061 PMCID: PMC7494789 DOI: 10.3389/fcell.2020.567537] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 08/14/2020] [Indexed: 01/06/2023] Open
Abstract
Growth-associated protein-43 (GAP-43) and brain acid-soluble protein 1 (BASP1) regulate actin dynamics and presynaptic vesicle cycling at axon terminals, thereby facilitating axonal growth, regeneration, and plasticity. These functions highly depend on changes in GAP-43 and BASP1 expression levels and post-translational modifications such as phosphorylation. Interestingly, examinations of GAP-43 and BASP1 in neurodegenerative diseases reveal alterations in their expression and phosphorylation profiles. This review provides an overview of the structural properties, regulations, and functions of GAP-43 and BASP1, highlighting their involvement in neural injury response and regeneration. By discussing GAP-43 and BASP1 in the context of neurodegenerative diseases, we also explore the therapeutic potential of modulating their activities to compensate for neuron loss in neurodegenerative diseases.
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Affiliation(s)
- Daayun Chung
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Andrew Shum
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Gabriela Caraveo
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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8
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Yuan M, Song ZH, Ying MD, Zhu H, He QJ, Yang B, Cao J. N-myristoylation: from cell biology to translational medicine. Acta Pharmacol Sin 2020; 41:1005-1015. [PMID: 32203082 PMCID: PMC7468318 DOI: 10.1038/s41401-020-0388-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 02/20/2020] [Indexed: 02/07/2023] Open
Abstract
Various lipids and lipid metabolites are bound to and modify the proteins in eukaryotic cells, which are known as ‘protein lipidation’. There are four major types of the protein lipidation, i.e. myristoylation, palmitoylation, prenylation, and glycosylphosphatidylinositol anchor. N-myristoylation refers to the attachment of 14-carbon fatty acid myristates to the N-terminal glycine of proteins by N-myristoyltransferases (NMT) and affects their physiology such as plasma targeting, subcellular tracking and localization, thereby influencing the function of proteins. With more novel pathogenic N-myristoylated proteins are identified, the N-myristoylation will attract great attentions in various human diseases including infectious diseases, parasitic diseases, and cancers. In this review, we summarize the current understanding of N-myristoylation in physiological processes and discuss the hitherto implication of crosstalk between N-myristoylation and other protein modification. Furthermore, we mention several well-studied NMT inhibitors mainly in infectious diseases and cancers and generalize the relation of NMT and cancer progression by browsing the clinic database. This review also aims to highlight the further investigation into the dynamic crosstalk of N-myristoylation in physiological processes as well as the potential application of protein N-myristoylation in translational medicine.
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9
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A Non-Canonical Calmodulin Target Motif Comprising a Polybasic Region and Lipidated Terminal Residue Regulates Localization. Int J Mol Sci 2020; 21:ijms21082751. [PMID: 32326637 PMCID: PMC7216078 DOI: 10.3390/ijms21082751] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/10/2020] [Accepted: 04/13/2020] [Indexed: 12/12/2022] Open
Abstract
Calmodulin (CaM) is a Ca2+-sensor that regulates a wide variety of target proteins, many of which interact through short basic helical motifs bearing two hydrophobic ‘anchor’ residues. CaM comprises two globular lobes, each containing a pair of EF-hand Ca2+-binding motifs that form a Ca2+-induced hydrophobic pocket that binds an anchor residue. A central flexible linker allows CaM to accommodate diverse targets. Several reported CaM interactors lack these anchors but contain Lys/Arg-rich polybasic sequences adjacent to a lipidated N- or C-terminus. Ca2+-CaM binds the myristoylated N-terminus of CAP23/NAP22 with intimate interactions between the lipid and a surface comprised of the hydrophobic pockets of both lobes, while the basic residues make electrostatic interactions with the negatively charged surface of CaM. Ca2+-CaM binds farnesylcysteine, derived from the farnesylated polybasic C-terminus of KRAS4b, with the lipid inserted into the C-terminal lobe hydrophobic pocket. CaM sequestration of the KRAS4b farnesyl moiety disrupts KRAS4b membrane association and downstream signaling. Phosphorylation of basic regions of N-/C-terminal lipidated CaM targets can reduce affinity for both CaM and the membrane. Since both N-terminal myristoylated and C-terminal prenylated proteins use a Singly Lipidated Polybasic Terminus (SLIPT) for CaM binding, we propose these polybasic lipopeptide elements comprise a non-canonical CaM-binding motif.
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10
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Grant BMM, Enomoto M, Back SI, Lee KY, Gebregiworgis T, Ishiyama N, Ikura M, Marshall CB. Calmodulin disrupts plasma membrane localization of farnesylated KRAS4b by sequestering its lipid moiety. Sci Signal 2020; 13:13/625/eaaz0344. [PMID: 32234958 DOI: 10.1126/scisignal.aaz0344] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
KRAS4b is a small guanosine triphosphatase (GTPase) protein that regulates several signal transduction pathways that underlie cell proliferation, differentiation, and survival. KRAS4b function requires prenylation of its C terminus and recruitment to the plasma membrane, where KRAS4b activates effector proteins including the RAF family of kinases. The Ca2+-sensing protein calmodulin (CaM) has been suggested to regulate the localization of KRAS4b through direct, Ca2+-dependent interaction, but how CaM and KRAS4b functionally interact is controversial. Here, we determined a crystal structure, which was supported by solution nuclear magnetic resonance (NMR), that revealed the sequestration of the prenyl moiety of KRAS4b in the hydrophobic pocket of the C-terminal lobe of Ca2+-bound CaM. Our engineered fluorescence resonance energy transfer (FRET)-based biosensor probes (CaMeRAS) showed that, upon stimulation of Ca2+ influx by extracellular ligands, KRAS4b reversibly translocated in a Ca2+-CaM-dependent manner from the plasma membrane to the cytoplasm in live HeLa and HEK293 cells. These results reveal a mechanism underlying the inhibition of KRAS4b activity by Ca2+ signaling pathways.
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Affiliation(s)
- Benjamin M M Grant
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Masahiro Enomoto
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Sung-In Back
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Ki-Young Lee
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Teklab Gebregiworgis
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Noboru Ishiyama
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Mitsuhiko Ikura
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada. .,Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Christopher B Marshall
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario M5G 1L7, Canada.
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11
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Hartl M, Puglisi K, Nist A, Raffeiner P, Bister K. The brain acid-soluble protein 1 (BASP1) interferes with the oncogenic capacity of MYC and its binding to calmodulin. Mol Oncol 2020; 14:625-644. [PMID: 31944520 PMCID: PMC7053243 DOI: 10.1002/1878-0261.12636] [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: 06/29/2019] [Revised: 12/16/2019] [Accepted: 01/09/2020] [Indexed: 12/13/2022] Open
Abstract
The MYC protein is a transcription factor with oncogenic potential controlling fundamental cellular processes such as cell proliferation, metabolism, differentiation, and apoptosis. The MYC gene is a major cancer driver, and elevated MYC protein levels are a hallmark of most human cancers. We have previously shown that the brain acid-soluble protein 1 gene (BASP1) is specifically downregulated by the v-myc oncogene and that ectopic BASP1 expression inhibits v-myc-induced cell transformation. The 11-amino acid effector domain of the BASP1 protein interacts with the calcium sensor calmodulin (CaM) and is mainly responsible for this inhibitory function. We also reported recently that CaM interacts with all MYC variant proteins and that ectopic CaM increases the transactivation and transformation potential of the v-Myc protein. Here, we show that the presence of excess BASP1 or of a synthetic BASP1 effector domain peptide leads to displacement of v-Myc from CaM. The protein stability of v-Myc is decreased in cells co-expressing v-Myc and BASP1, which may account for the inhibition of v-Myc. Furthermore, suppression of v-Myc-triggered transcriptional activation and cell transformation is compensated by ectopic CaM, suggesting that BASP1-mediated withdrawal of CaM from v-Myc is a crucial event in the inhibition. In view of the tumor-suppressive role of BASP1 which was recently also reported for human cancer, small compounds or peptides based on the BASP1 effector domain could be used in drug development strategies aimed at tumors with high MYC expression.
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Affiliation(s)
- Markus Hartl
- Institute of Biochemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Austria
| | - Kane Puglisi
- Institute of Biochemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Austria
| | - Andrea Nist
- Institute of Biochemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Austria
| | - Philipp Raffeiner
- Institute of Biochemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Austria
| | - Klaus Bister
- Institute of Biochemistry and Center for Molecular Biosciences (CMBI), University of Innsbruck, Austria
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12
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Jang H, Banerjee A, Marcus K, Makowski L, Mattos C, Gaponenko V, Nussinov R. The Structural Basis of the Farnesylated and Methylated KRas4B Interaction with Calmodulin. Structure 2019; 27:1647-1659.e4. [PMID: 31495533 DOI: 10.1016/j.str.2019.08.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 07/31/2019] [Accepted: 08/16/2019] [Indexed: 02/07/2023]
Abstract
Ca2+-calmodulin (CaM) extracts KRas4B from the plasma membrane, suggesting that KRas4B/CaM interaction plays a role in regulating Ras signaling. To gain mechanistic insight, we provide a computational model, supported by experimental structural data, of farnesylated/methylated KRas4B1-185 interacting with CaM in solution and at anionic membranes including signaling lipids. Due to multiple interaction modes, we observe diverse conformational ensembles of the KRas4B-CaM complex. A highly populated conformation reveals the catalytic domain interacting with the N-lobe and the hypervariable region (HVR) wrapping around the linker with the farnesyl docking to the extended CaM's C-lobe pocket. Alternatively, KRas4B can interact with collapsed CaM with the farnesyl penetrating CaM's center. At anionic membranes, CaM interacts with the catalytic domain with large fluctuations, drawing the HVR. Signaling lipids establishing strong salt bridges with CaM prevent membrane departure. Membrane-interacting KRas4B-CaM complex can productively recruit phosphatidylinositol 3-kinase α (PI3Kα) to the plasma membrane, serving as a coagent in activating PI3Kα/Akt signaling.
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Affiliation(s)
- Hyunbum Jang
- Computational Structural Biology Section, Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Avik Banerjee
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Kendra Marcus
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA
| | - Lee Makowski
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA
| | - Carla Mattos
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USA
| | - Vadim Gaponenko
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Ruth Nussinov
- Computational Structural Biology Section, Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA; Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
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13
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Hartl M, Schneider R. A Unique Family of Neuronal Signaling Proteins Implicated in Oncogenesis and Tumor Suppression. Front Oncol 2019; 9:289. [PMID: 31058089 PMCID: PMC6478813 DOI: 10.3389/fonc.2019.00289] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 03/29/2019] [Indexed: 12/20/2022] Open
Abstract
The neuronal proteins GAP43 (neuromodulin), MARCKS, and BASP1 are highly expressed in the growth cones of nerve cells where they are involved in signal transmission and cytoskeleton organization. Although their primary structures are unrelated, these signaling proteins share several structural properties like fatty acid modification, and the presence of cationic effector domains. GAP43, MARCKS, and BASP1 bind to cell membrane phospholipids, a process reversibly regulated by protein kinase C-phosphorylation or by binding to the calcium sensor calmodulin (CaM). GAP43, MARCKS, and BASP1 are also expressed in non-neuronal cells, where they may have important functions to manage cytoskeleton architecture, and in case of MARCKS and BASP1 to act as cofactors in transcriptional regulation. During neoplastic cell transformation, the proteins reveal differential expression in normal vs. tumor cells, and display intrinsic tumor promoting or tumor suppressive activities. Whereas GAP43 and MARCKS are oncogenic, tumor suppressive functions have been ascribed to BASP1 and in part to MARCKS depending on the cell type. Like MARCKS, the myristoylated BASP1 protein is localized both in the cytoplasm and in the cell nucleus. Nuclear BASP1 participates in gene regulation converting the Wilms tumor transcription factor WT1 from an oncoprotein into a tumor suppressor. The BASP1 gene is downregulated in many human tumor cell lines particularly in those derived from leukemias, which display elevated levels of WT1 and of the major cancer driver MYC. BASP1 specifically inhibits MYC-induced cell transformation in cultured cells. The tumor suppressive functions of BASP1 and MARCKS could be exploited to expand the spectrum of future innovative therapeutic approaches to inhibit growth and viability of susceptible human tumors.
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Affiliation(s)
- Markus Hartl
- Center of Molecular Biosciences (CMBI), Institute of Biochemistry, University of Innsbruck, Innsbruck, Austria
| | - Rainer Schneider
- Center of Molecular Biosciences (CMBI), Institute of Biochemistry, University of Innsbruck, Innsbruck, Austria
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14
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Agamasu C, Ghirlando R, Taylor T, Messing S, Tran TH, Bindu L, Tonelli M, Nissley DV, McCormick F, Stephen AG. KRAS Prenylation Is Required for Bivalent Binding with Calmodulin in a Nucleotide-Independent Manner. Biophys J 2019; 116:1049-1063. [PMID: 30846362 PMCID: PMC6428923 DOI: 10.1016/j.bpj.2019.02.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/30/2019] [Accepted: 02/04/2019] [Indexed: 12/11/2022] Open
Abstract
Deregulation of KRAS4b signaling pathway has been implicated in 30% of all cancers. Membrane localization of KRAS4b is an essential step for the initiation of the downstream signaling cascades that guide various cellular mechanisms. KRAS4b plasma membrane (PM) binding is mediated by the insertion of a prenylated moiety that is attached to the terminal carboxy-methylated cysteine, in addition to electrostatic interactions of its positively charged hypervariable region with anionic lipids. Calmodulin (CaM) has been suggested to selectively bind KRAS4b to act as a negative regulator of the RAS/mitogen-activated protein kinase (MAPK) signaling pathway by displacing KRAS4b from the membrane. However, the mechanism by which CaM can recognize and displace KRAS4b from the membrane is not well understood. In this study, we employed biophysical and structural techniques to characterize this mechanism in detail. We show that KRAS4b prenylation is required for binding to CaM and that the hydrophobic pockets of CaM can accommodate the prenylated region of KRAS4b, which might represent a novel CaM-binding motif. Remarkably, prenylated KRAS4b forms a 2:1 stoichiometric complex with CaM in a nucleotide-independent manner. The interaction between prenylated KRAS4b and CaM is enthalpically driven, and electrostatic interactions also contribute to the formation of the complex. The prenylated KRAS4b terminal KSKTKC-farnesylation and carboxy-methylation is sufficient for binding and defines the minimal CaM-binding motif. This is the same region implicated in membrane and phosphodiesterase6-δ binding. Finally, we provide a structure-based docking model by which CaM binds to prenylated KRAS4b. Our data provide new insights into the KRAS4b-CaM interaction and suggest a possible mechanism whereby CaM can regulate KRAS4b membrane localization.
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Affiliation(s)
- Constance Agamasu
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Troy Taylor
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland
| | - Simon Messing
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland
| | - Timothy H Tran
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland
| | - Lakshman Bindu
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland
| | - Marco Tonelli
- National Magnetic Resource Facility at Madison, Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin
| | - Dwight V Nissley
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland
| | - Frank McCormick
- Diller Family Comprehensive Cancer Center, University of California, San Francisco, California
| | - Andrew G Stephen
- NCI RAS Initiative, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland.
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15
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Ghazarian H, Hu W, Mao A, Nguyen T, Vaidehi N, Sligar S, Shively JE. NMR analysis of free and lipid nanodisc anchored CEACAM1 membrane proximal peptides with Ca 2+/CaM. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:787-797. [PMID: 30639287 DOI: 10.1016/j.bbamem.2019.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/16/2018] [Accepted: 01/08/2019] [Indexed: 11/28/2022]
Abstract
CEACAM1, a homotypic transmembrane receptor with 12 or 72 amino acid cytosolic domain isoforms, is converted from inactive cis-dimers to active trans-dimers by calcium-calmodulin (Ca2+/CaM). Previously, the weak binding of Ca2+/CaM to the human 12 AA cytosolic domain was studied using C-terminal anchored peptides. We now show the binding of 15N labeled Phe-454 cytosolic domain peptides in solution or membrane anchored using NMR demonstrates a significant role for the lipid bilayer. Although binding is increased by the mutation Phe454Ala, this mutation was previously shown to abrogate actin binding. On the other hand, Ca2+/CaM binding is abrogated by phosphorylation of nearby Thr-457, a post-translation modification required for actin binding and subsequent in vitro lumen formation. Binding of Ca2+/CaM to a membrane proximal peptide from the long 72 AA cytosolic domain anchored to lipid nanodiscs was very weak compared to lipid free conditions, suggesting membrane specific effects between the two isoforms. NMR analysis of 15N labeled Ca2+/CaM with unlabeled peptides showed the C-lobe of Ca2+/CaM is involved in peptide interactions, and hydrophobic residues such as Met-109, Val-142 and Met-144 play important roles in binding peptide. This information was incorporated into transmembrane models of CEACAM1 binding to Ca2+/CaM. The lack of Ca2+/CaM binding to phosphorylated Thr-457, a residue we have previously shown to be phosphorylated by CaMK2D, also dependent on Ca2+/CaM, suggests stepwise binding of the cytosolic domain first to Ca2+/CaM and then to actin.
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Affiliation(s)
- Haike Ghazarian
- Department of Molecular Imaging and Therapy, Diabetes, Metabolism and Research Institute of City of Hope, 1450 East Duarte Road, Duarte, CA 91010, United States of America; City of Hope Irell and Manella Graduate School of Biological Sciences, 1450 East Duarte road, Duarte, CA 91010, United States of America
| | - Weidong Hu
- Department of Molecular Imaging and Therapy, Diabetes, Metabolism and Research Institute of City of Hope, 1450 East Duarte Road, Duarte, CA 91010, United States of America
| | - Allen Mao
- Department of Molecular Imaging and Therapy, Diabetes, Metabolism and Research Institute of City of Hope, 1450 East Duarte Road, Duarte, CA 91010, United States of America
| | - Tung Nguyen
- Department of Molecular Imaging and Therapy, Diabetes, Metabolism and Research Institute of City of Hope, 1450 East Duarte Road, Duarte, CA 91010, United States of America
| | - Nagarajan Vaidehi
- Department of Molecular Imaging and Therapy, Diabetes, Metabolism and Research Institute of City of Hope, 1450 East Duarte Road, Duarte, CA 91010, United States of America
| | - Stephen Sligar
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, United States of America
| | - John E Shively
- Department of Molecular Imaging and Therapy, Diabetes, Metabolism and Research Institute of City of Hope, 1450 East Duarte Road, Duarte, CA 91010, United States of America.
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16
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Garrido E, Lázaro J, Jaumot M, Agell N, Rubio-Martinez J. Modeling and subtleties of K-Ras and Calmodulin interaction. PLoS Comput Biol 2018; 14:e1006552. [PMID: 30376570 PMCID: PMC6226203 DOI: 10.1371/journal.pcbi.1006552] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 11/09/2018] [Accepted: 10/08/2018] [Indexed: 12/12/2022] Open
Abstract
K-Ras, one of the most common small GTPases of the cell, still presents many riddles, despite the intense efforts to unveil its mysteries. Such is the case of its interaction with Calmodulin, a small acidic protein known for its role as a calcium ion sensor. Although the interaction between these two proteins and its biological implications have been widely studied, a model of their interaction has not been performed. In the present work we analyse this intriguing interaction by computational means. To do so, both conventional molecular dynamics and scaled molecular dynamics have been used. Our simulations suggest a model in which Calmodulin would interact with both the hypervariable region and the globular domain of K-Ras, using a lobe to interact with each of them. According to the presented model, the interface of helixes α4 and α5 of the globular domain of K-Ras would be relevant for the interaction with a lobe of Calmodulin. These results were also obtained when bringing the proteins together in a step wise manner with the umbrella sampling methodology. The computational results have been validated using SPR to determine the relevance of certain residues. Our results demonstrate that, when mutating residues of the α4-α5 interface described to be relevant for the interaction with Calmodulin, the interaction of the globular domain of K-Ras with Calmodulin diminishes. However, it is to be considered that our simulations indicate that the bulk of the interaction would fall on the hypervariable region of K-Ras, as many more interactions are identified in said region. All in all our simulations present a suitable model in which K-Ras could interact with Calmodulin at membrane level using both its globular domain and its hypervariable region to stablish an interaction that leads to an altered signalling. K-Ras is one of the most mutated oncogenes in human cancer. Although several studies validate K-Ras protein as good candidate for direct therapeutic targeting, pharmacologic targeting has not been successful. During the last years increasing evidences demonstrate that oncogenic K-Ras activity can be modulated in vivo by dimerization, nanoclustering at the plasma membrane or interaction with non-effector proteins, consequently opening new therapeutic strategies. We have previously demonstrated that Calmodulin, an ubiquitous Ca2+-binding protein, is one of this K-Ras interacting proteins and that it negatively modulates K-Ras signaling. Although experimental data were available showing the relevant regions for this interaction, a model of K-Ras and Calmodulin interaction was missing. In the present work by using different computational modeling techniques we obtained a model for this interaction that agrees with the experimental data. We believe the present model will help to better understand K-Ras regulation, and to design new inhibitors. For instance, base on our model, we can predict that the interaction can take place at the plasma membrane, and that since the surface of K-Ras that interact with Calmodulin is the same that it uses for dimerization, that Calmodulin could be inhibiting K-Ras dimerization.
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Affiliation(s)
- Eduardo Garrido
- Department of Materials Science and Physical Chemistry, Universitat de Barcelona, Institut de Recerca en Química Teòrica i Computacional (IQTCUB), Barcelona, Spain
- Department de Biomedicina, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, IDIBAPS, Barcelona, Spain
| | - Juan Lázaro
- Department de Biomedicina, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, IDIBAPS, Barcelona, Spain
| | - Montserrat Jaumot
- Department de Biomedicina, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, IDIBAPS, Barcelona, Spain
| | - Neus Agell
- Department de Biomedicina, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, IDIBAPS, Barcelona, Spain
- * E-mail: (NA); (JRM)
| | - Jaime Rubio-Martinez
- Department of Materials Science and Physical Chemistry, Universitat de Barcelona, Institut de Recerca en Química Teòrica i Computacional (IQTCUB), Barcelona, Spain
- * E-mail: (NA); (JRM)
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17
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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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18
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Raffeiner P, Schraffl A, Schwarz T, Röck R, Ledolter K, Hartl M, Konrat R, Stefan E, Bister K. Calcium-dependent binding of Myc to calmodulin. Oncotarget 2018; 8:3327-3343. [PMID: 27926480 PMCID: PMC5356885 DOI: 10.18632/oncotarget.13759] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 11/21/2016] [Indexed: 12/13/2022] Open
Abstract
The bHLH-LZ (basic region/helix-loop-helix/leucine zipper) oncoprotein Myc and the bHLH-LZ protein Max form a binary transcription factor complex controlling fundamental cellular processes. Deregulated Myc expression leads to neoplastic transformation and is a hallmark of most human cancers. The dynamics of Myc transcription factor activity are post-translationally coordinated by defined protein-protein interactions. Here, we present evidence for a second messenger controlled physical interaction between the Ca2+ sensor calmodulin (CaM) and all Myc variants (v-Myc, c-Myc, N-Myc, and L-Myc). The predominantly cytoplasmic Myc:CaM interaction is Ca2+-dependent, and the binding site maps to the conserved bHLH domain of Myc. Ca2+-loaded CaM binds the monomeric and intrinsically disordered Myc protein with high affinity, whereas Myc:Max heterodimers show less, and Max homodimers no affinity for CaM. NMR spectroscopic analyses using alternating mixtures of 15N-labeled and unlabeled preparations of CaM and a monomeric Myc fragment containing the bHLH-LZ domain corroborate the biochemical results on the Myc:CaM interaction and confirm the interaction site mapping. In electrophoretic mobility shift assays, addition of CaM does not affect high-affinity DNA-binding of Myc:Max heterodimers. However, cell-based reporter analyses and cell transformation assays suggest that increasing CaM levels enhance Myc transcriptional and oncogenic activities. Our results point to a possible involvement of Ca2+ sensing CaM in the fine-tuning of Myc function.
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Affiliation(s)
- Philipp Raffeiner
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020 Innsbruck, Austria.,Present address: Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Andrea Schraffl
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Thomas Schwarz
- Max F. Perutz Laboratories, Department of Structural and Computational Biology, University of Vienna, A-1030 Vienna, Austria
| | - Ruth Röck
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Karin Ledolter
- Max F. Perutz Laboratories, Department of Structural and Computational Biology, University of Vienna, A-1030 Vienna, Austria
| | - Markus Hartl
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Robert Konrat
- Max F. Perutz Laboratories, Department of Structural and Computational Biology, University of Vienna, A-1030 Vienna, Austria
| | - Eduard Stefan
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Klaus Bister
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, A-6020 Innsbruck, Austria
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19
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Jiang H, Zhang X, Chen X, Aramsangtienchai P, Tong Z, Lin H. Protein Lipidation: Occurrence, Mechanisms, Biological Functions, and Enabling Technologies. Chem Rev 2018; 118:919-988. [PMID: 29292991 DOI: 10.1021/acs.chemrev.6b00750] [Citation(s) in RCA: 283] [Impact Index Per Article: 47.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Protein lipidation, including cysteine prenylation, N-terminal glycine myristoylation, cysteine palmitoylation, and serine and lysine fatty acylation, occurs in many proteins in eukaryotic cells and regulates numerous biological pathways, such as membrane trafficking, protein secretion, signal transduction, and apoptosis. We provide a comprehensive review of protein lipidation, including descriptions of proteins known to be modified and the functions of the modifications, the enzymes that control them, and the tools and technologies developed to study them. We also highlight key questions about protein lipidation that remain to be answered, the challenges associated with answering such questions, and possible solutions to overcome these challenges.
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Affiliation(s)
- Hong Jiang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Xiaoyu Zhang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Xiao Chen
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Pornpun Aramsangtienchai
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Zhen Tong
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Hening Lin
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
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20
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Abstract
Membrane binding of viral and cellular N-myristoylated proteins can be regulated by selectively sequestering myristate. In this issue of Cell Host & Microbe, Zhu et al. (2017) report on a myristate binding site within the cellular protein heme oxygenase-2 that acts as a trap to inhibit N-myristoylated protein function.
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Affiliation(s)
- Marilyn D Resh
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, Box 143, New York, NY 10065, USA.
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21
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Jang H, Banerjee A, Chavan T, Gaponenko V, Nussinov R. Flexible-body motions of calmodulin and the farnesylated hypervariable region yield a high-affinity interaction enabling K-Ras4B membrane extraction. J Biol Chem 2017; 292:12544-12559. [PMID: 28623230 PMCID: PMC5535030 DOI: 10.1074/jbc.m117.785063] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 06/05/2017] [Indexed: 01/01/2023] Open
Abstract
In calmodulin (CaM)-rich environments, oncogenic KRAS plays a critical role in adenocarcinomas by promoting PI3K/Akt signaling. We previously proposed that at elevated calcium levels in cancer, CaM recruits PI3Kα to the membrane and extracts K-Ras4B from the membrane, organizing a K-Ras4B-CaM-PI3Kα ternary complex. CaM can thereby replace a missing receptor-tyrosine kinase signal to fully activate PI3Kα. Recent experimental data show that CaM selectively promotes K-Ras signaling but not of N-Ras or H-Ras. How CaM specifically targets K-Ras and how it extracts it from the membrane in KRAS-driven cancer is unclear. Obtaining detailed structural information for a CaM-K-Ras complex is still challenging. Here, using molecular dynamics simulations and fluorescence experiments, we observed that CaM preferentially binds unfolded K-Ras4B hypervariable regions (HVRs) and not α-helical HVRs. The interaction involved all three CaM domains including the central linker and both lobes. CaM specifically targeted the highly polybasic anchor region of the K-Ras4B HVR that stably wraps around CaM's acidic linker. The docking of the farnesyl group to the hydrophobic pockets located at both CaM lobes further enhanced CaM-HVR complex stability. Both CaM and K-Ras4B HVR are highly flexible molecules, suggesting that their interactions permit highly dynamic flexible-body motions. We, therefore, anticipate that the flexible-body interaction is required to extract K-Ras4B from the membrane, as conformational plasticity enables CaM to orient efficiently to the polybasic HVR anchor, which is partially diffused into the liquid-phase membrane. Our structural model of the CaM-K-Ras4B HVR association provides plausible clues to CaM's regulatory action in PI3Kα activation involving the ternary complex in cell proliferation signaling by oncogenic K-Ras.
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Affiliation(s)
- Hyunbum Jang
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, NCI-Frederick, Frederick, Maryland 21702
| | - Avik Banerjee
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607
| | - Tanmay Chavan
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305
| | - Vadim Gaponenko
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois 60607.
| | - Ruth Nussinov
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, NCI-Frederick, Frederick, Maryland 21702; Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
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22
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Sperlich B, Kapoor S, Waldmann H, Winter R, Weise K. Regulation of K-Ras4B Membrane Binding by Calmodulin. Biophys J 2017; 111:113-22. [PMID: 27410739 DOI: 10.1016/j.bpj.2016.05.042] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 05/03/2016] [Accepted: 05/24/2016] [Indexed: 12/28/2022] Open
Abstract
K-Ras4B is a membrane-bound small GTPase with a prominent role in cancer development. It contains a polybasic farnesylated C-terminus that is required for the correct localization and clustering of K-Ras4B in distinct membrane domains. PDEδ and the Ca(2+)-binding protein calmodulin (CaM) are known to function as potential binding partners for farnesylated Ras proteins. However, they differ in the number of interaction sites with K-Ras4B, leading to different modes of interaction, and thus affect the subcellular distribution of K-Ras4B in different ways. Although it is clear that Ca(2+)-bound CaM can play a role in the dynamic spatial cycle of K-Ras4B in the cell, the exact molecular mechanism is only partially understood. In this biophysical study, we investigated the effect of Ca(2+)/CaM on the interaction of GDP- and GTP-loaded K-Ras4B with heterogeneous model biomembranes by using a combination of different spectroscopic and imaging techniques. The results show that Ca(2+)/CaM is able to extract K-Ras4B from negatively charged membranes in a nucleotide-independent manner. Moreover, the data demonstrate that the complex of Ca(2+)/CaM and K-Ras4B is stable in the presence of anionic membranes and shows no membrane binding. Finally, the influence of Ca(2+)/CaM on the interaction of K-Ras4B with membranes is compared with that of PDEδ, which was investigated in a previous study. Although both CaM and PDEδ exhibit a hydrophobic binding pocket for farnesyl, they have different effects on membrane binding of K-Ras4B and hence should be capable of regulating K-Ras4B plasma membrane localization in the cell.
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Affiliation(s)
- Benjamin Sperlich
- Physical Chemistry I - Biophysical Chemistry, TU Dortmund University, Dortmund, Germany
| | - Shobhna Kapoor
- Chemical Biology, TU Dortmund University, Dortmund, Germany; Department of Chemical Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Herbert Waldmann
- Chemical Biology, TU Dortmund University, Dortmund, Germany; Department of Chemical Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, TU Dortmund University, Dortmund, Germany.
| | - Katrin Weise
- Physical Chemistry I - Biophysical Chemistry, TU Dortmund University, Dortmund, Germany.
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23
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Zhu R, Yang T, Kobeissy F, Mouhieddine TH, Raad M, Nokkari A, Gold MS, Wang KK, Mechref Y. The Effect of Chronic Methamphetamine Exposure on the Hippocampal and Olfactory Bulb Neuroproteomes of Rats. PLoS One 2016; 11:e0151034. [PMID: 27082425 PMCID: PMC4833297 DOI: 10.1371/journal.pone.0151034] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 02/23/2016] [Indexed: 01/23/2023] Open
Abstract
Nowadays, drug abuse and addiction are serious public health problems in the USA. Methamphetamine (METH) is one of the most abused drugs and is known to cause brain damage after repeated exposure. In this paper, we conducted a neuroproteomic study to evaluate METH-induced brain protein dynamics, following a two-week chronic regimen of an escalating dose of METH exposure. Proteins were extracted from rat brain hippocampal and olfactory bulb tissues and subjected to liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Both shotgun and targeted proteomic analysis were performed. Protein quantification was initially based on comparing the spectral counts between METH exposed animals and their control counterparts. Quantitative differences were further confirmed through multiple reaction monitoring (MRM) LC-MS/MS experiments. According to the quantitative results, the expression of 18 proteins (11 in the hippocampus and 7 in the olfactory bulb) underwent a significant alteration as a result of exposing rats to METH. 13 of these proteins were up-regulated after METH exposure while 5 were down-regulated. The altered proteins belonging to different structural and functional families were involved in processes such as cell death, inflammation, oxidation, and apoptosis.
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Affiliation(s)
- Rui Zhu
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Tianjiao Yang
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Firas Kobeissy
- Department of Psychiatry, Center for Neuroproteomics and Biomarkers Research, University of Florida, Gainesville, FL, United States of America
| | - Tarek H. Mouhieddine
- Faculty of Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Mohamad Raad
- Faculty of Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Amaly Nokkari
- Faculty of Medicine, Department of Biochemistry and Molecular Genetics, American University of Beirut Medical Center, Beirut, Lebanon
| | - Mark S. Gold
- Department of Psychiatry, Center for Neuroproteomics and Biomarkers Research, University of Florida, Gainesville, FL, United States of America
| | - Kevin K. Wang
- Department of Psychiatry, Center for Neuroproteomics and Biomarkers Research, University of Florida, Gainesville, FL, United States of America
- * E-mail: (YM); (KKW)
| | - Yehia Mechref
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
- * E-mail: (YM); (KKW)
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24
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Identification of the Calmodulin-Binding Domains of Fas Death Receptor. PLoS One 2016; 11:e0146493. [PMID: 26735300 PMCID: PMC4703387 DOI: 10.1371/journal.pone.0146493] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 12/17/2015] [Indexed: 01/25/2023] Open
Abstract
The extrinsic apoptotic pathway is initiated by binding of a Fas ligand to the ectodomain of the surface death receptor Fas protein. Subsequently, the intracellular death domain of Fas (FasDD) and that of the Fas-associated protein (FADD) interact to form the core of the death-inducing signaling complex (DISC), a crucial step for activation of caspases that induce cell death. Previous studies have shown that calmodulin (CaM) is recruited into the DISC in cholangiocarcinoma cells and specifically interacts with FasDD to regulate the apoptotic/survival signaling pathway. Inhibition of CaM activity in DISC stimulates apoptosis significantly. We have recently shown that CaM forms a ternary complex with FasDD (2:1 CaM:FasDD). However, the molecular mechanism by which CaM binds to two distinct FasDD motifs is not fully understood. Here, we employed mass spectrometry, nuclear magnetic resonance (NMR), biophysical, and biochemical methods to identify the binding regions of FasDD and provide a molecular basis for the role of CaM in Fas-mediated apoptosis. Proteolytic digestion and mass spectrometry data revealed that peptides spanning residues 209-239 (Fas-Pep1) and 251-288 (Fas-Pep2) constitute the two CaM-binding regions of FasDD. To determine the molecular mechanism of interaction, we have characterized the binding of recombinant/synthetic Fas-Pep1 and Fas-Pep2 peptides with CaM. Our data show that both peptides engage the N- and C-terminal lobes of CaM simultaneously. Binding of Fas-Pep1 to CaM is entropically driven while that of Fas-Pep2 to CaM is enthalpically driven, indicating that a combination of electrostatic and hydrophobic forces contribute to the stabilization of the FasDD-CaM complex. Our data suggest that because Fas-Pep1 and Fas-Pep2 are involved in extensive intermolecular contacts with the death domain of FADD, binding of CaM to these regions may hinder its ability to bind to FADD, thus greatly inhibiting the initiation of apoptotic signaling pathway.
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25
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Erwin N, Patra S, Winter R. Probing conformational and functional substates of calmodulin by high pressure FTIR spectroscopy: influence of Ca2+ binding and the hypervariable region of K-Ras4B. Phys Chem Chem Phys 2016; 18:30020-30028. [DOI: 10.1039/c6cp06553h] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using pressure perturbation, conformational substates of CaM could be uncovered that conceivably facilitate target recognition by exposing the required binding surfaces.
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Affiliation(s)
- Nelli Erwin
- Physical Chemistry I - Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
| | - Satyajit Patra
- Physical Chemistry I - Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
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26
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Flamm AG, Le Roux AL, Mateos B, Díaz-Lobo M, Storch B, Breuker K, Konrat R, Pons M, Coudevylle N. N-Lauroylation during the Expression of Recombinant N-Myristoylated Proteins: Implications and Solutions. Chembiochem 2016; 17:82-9. [PMID: 26522884 PMCID: PMC4736449 DOI: 10.1002/cbic.201500454] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Indexed: 12/12/2022]
Abstract
Incorporation of myristic acid onto the N terminus of a protein is a crucial modification that promotes membrane binding and correct localization of important components of signaling pathways. Recombinant expression of N-myristoylated proteins in Escherichia coli can be achieved by co-expressing yeast N-myristoyltransferase and supplementing the growth medium with myristic acid. However, undesired incorporation of the 12-carbon fatty acid lauric acid can also occur (leading to heterogeneous samples), especially when the available carbon sources are scarce, as it is the case in minimal medium for the expression of isotopically enriched samples. By applying this method to the brain acid soluble protein 1 and the 1-185 N-terminal region of c-Src, we show the significant, and protein-specific, differences in the membrane binding properties of lauroylated and myristoylated forms. We also present a robust strategy for obtaining lauryl-free samples of myristoylated proteins in both rich and minimal media.
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Affiliation(s)
- Andrea Gabriele Flamm
- Department of Computational and Structural Biology, F. Max Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Anabel-Lise Le Roux
- Biomolecular NMR Laboratory, Department of Organic Chemistry, University of Barcelona, Baldiri Reixac 10-12, 08028, Barcelona, Spain
- Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Borja Mateos
- Biomolecular NMR Laboratory, Department of Organic Chemistry, University of Barcelona, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Mireia Díaz-Lobo
- Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Barbara Storch
- Institute of Organic Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, CCB, Innrain 80/82, 6020, Innsbruck, Austria
| | - Kathrin Breuker
- Institute of Organic Chemistry, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, CCB, Innrain 80/82, 6020, Innsbruck, Austria
| | - Robert Konrat
- Department of Computational and Structural Biology, F. Max Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Miquel Pons
- Biomolecular NMR Laboratory, Department of Organic Chemistry, University of Barcelona, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Nicolas Coudevylle
- Department of Computational and Structural Biology, F. Max Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria.
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27
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Agamasu C, Ghanam RH, Saad JS. Structural and Biophysical Characterization of the Interactions between Calmodulin and the Pleckstrin Homology Domain of Akt. J Biol Chem 2015; 290:27403-27413. [PMID: 26391397 DOI: 10.1074/jbc.m115.673939] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Indexed: 11/06/2022] Open
Abstract
The translocation of Akt, a serine/threonine kinase, to the plasma membrane is a critical step in the Akt activation pathway. It is established that membrane binding of Akt is mediated by direct interactions between its pleckstrin homology domain (PHD) and phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3). There is now evidence that Akt activation in many breast cancer cells is also modulated by the calcium-binding protein, calmodulin (CaM). Upon EGF stimulation of breast cancer cells, CaM co-localizes with Akt at the plasma membrane to enhance activation. However, the molecular details of Akt(PHD) interaction with CaM are not known. In this study, we employed NMR, biochemical, and biophysical techniques to characterize CaM binding to Akt(PHD). Our data show that CaM forms a tight complex with the PHD of Akt (dissociation constant = 100 nm). The interaction between CaM and Akt(PHD) is enthalpically driven, and the affinity is greatly dependent on salt concentration, indicating that electrostatic interactions are important for binding. The CaM-binding interface in Akt(PHD) was mapped to two loops adjacent to the PI(3,4,5)P3 binding site, which represents a rare CaM-binding motif and suggests a synergistic relationship between CaM and PI(3,4,5)P3 upon Akt activation. Elucidation of the mechanism by which Akt interacts with CaM will help in understanding the activation mechanism, which may provide insights for new potential targets to control the pathophysiological processes of cell survival.
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Affiliation(s)
- Constance Agamasu
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Ruba H Ghanam
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Jamil S Saad
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294.
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28
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Marshall CB, Nishikawa T, Osawa M, Stathopulos PB, Ikura M. Calmodulin and STIM proteins: Two major calcium sensors in the cytoplasm and endoplasmic reticulum. Biochem Biophys Res Commun 2015; 460:5-21. [PMID: 25998729 DOI: 10.1016/j.bbrc.2015.01.106] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 01/22/2015] [Indexed: 01/22/2023]
Abstract
The calcium (Ca(2+)) ion is a universal signalling messenger which plays vital physiological roles in all eukaryotes. To decode highly regulated intracellular Ca(2+) signals, cells have evolved a number of sensor proteins that are ideally adapted to respond to a specific range of Ca(2+) levels. Among many such proteins, calmodulin (CaM) is a multi-functional cytoplasmic Ca(2+) sensor with a remarkable ability to interact with and regulate a plethora of structurally diverse target proteins. CaM achieves this 'multi-talented' functionality through two EF-hand domains, each with an independent capacity to bind targets, and an adaptable flexible linker. By contrast, stromal interaction molecule-1 and -2 (STIMs) have evolved for a specific role in endoplasmic reticulum (ER) Ca(2+) sensing using EF-hand machinery analogous to CaM; however, whereas CaM structurally adjusts to dissimilar binding partners, STIMs use the EF-hand machinery to self-regulate the stability of the Ca(2+) sensing domain. The molecular mechanisms underlying the Ca(2+)-dependent signal transduction by CaM and STIMs have revealed a remarkable repertoire of actions and underscore the flexibility of nature in molecular evolution and adaption to discrete Ca(2+) levels. Recent genomic sequencing efforts have uncovered a number of disease-associated mutations in both CaM and STIM1. This article aims to highlight the most recent key structural and functional findings in the CaM and STIM fields, and discusses how these two Ca(2+) sensor proteins execute their biological functions.
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Affiliation(s)
- Christopher B Marshall
- Princess Margaret Cancer Centre, University Health Network and University of Toronto, Toronto, Ontario, M5G 1L7, Canada
| | - Tadateru Nishikawa
- Princess Margaret Cancer Centre, University Health Network and University of Toronto, Toronto, Ontario, M5G 1L7, Canada
| | - Masanori Osawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Tokyo, 113-0033, Japan
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, N6A 5C1, Canada.
| | - Mitsuhiko Ikura
- Princess Margaret Cancer Centre, University Health Network and University of Toronto, Toronto, Ontario, M5G 1L7, Canada.
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29
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Kurzbach D, Kontaxis G, Coudevylle N, Konrat R. NMR Spectroscopic Studies of the Conformational Ensembles of Intrinsically Disordered Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 870:149-85. [PMID: 26387102 DOI: 10.1007/978-3-319-20164-1_5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intrinsically disordered proteins (IDPs) are characterized by substantial conformational flexibility and thus not amenable to conventional structural biology techniques. Given their inherent structural flexibility NMR spectroscopy offers unique opportunities for structural and dynamic studies of IDPs. The past two decades have witnessed significant development of NMR spectroscopy that couples advances in spin physics and chemistry with a broad range of applications. This chapter will summarize key advances in NMR methodology. Despite the availability of efficient (multi-dimensional) NMR experiments for signal assignment of IDPs it is discussed that NMR of larger and more complex IDPs demands spectral simplification strategies capitalizing on specific isotope-labeling strategies. Prototypical applications of isotope labeling-strategies are described. Since IDP-ligand association and dissociation processes frequently occur on time scales that are amenable to NMR spectroscopy we describe in detail the application of CPMG relaxation dispersion techniques to studies of IDP protein binding. Finally, we demonstrate that the complementary usage of NMR and EPR data provide a more comprehensive picture about the conformational states of IDPs and can be employed to analyze the conformational ensembles of IDPs.
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Affiliation(s)
- Dennis Kurzbach
- Department of Computational and Structural Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Georg Kontaxis
- Department of Computational and Structural Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Nicolas Coudevylle
- Department of Computational and Structural Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Robert Konrat
- Department of Computational and Structural Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria.
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30
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Takamitsu E, Fukunaga K, Iio Y, Moriya K, Utsumi T. Cell-free identification of novel N-myristoylated proteins from complementary DNA resources using bioorthogonal myristic acid analogues. Anal Biochem 2014; 464:83-93. [PMID: 25043870 DOI: 10.1016/j.ab.2014.07.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/08/2014] [Accepted: 07/09/2014] [Indexed: 12/17/2022]
Abstract
To establish a non-radioactive, cell-free detection system for protein N-myristoylation, metabolic labeling in a cell-free protein synthesis system using bioorthogonal myristic acid analogues was performed. After Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) with a biotin tag, the tagged proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and blotted on a polyvinylidene fluoride (PVDF) membrane, and then protein N-myristoylation was detected by enhanced chemiluminescence (ECL) using horseradish peroxidase (HRP)-conjugated streptavidin. The results showed that metabolic labeling in an insect cell-free protein synthesis system using an azide analogue of myristic acid followed by CuAAC with alkynyl biotin was the most effective strategy for cell-free detection of protein N-myristoylation. To determine whether the newly developed detection method can be applied for the detection of novel N-myristoylated proteins from complementary DNA (cDNA) resources, four candidate cDNA clones were selected from a human cDNA resource and their susceptibility to protein N-myristoylation was evaluated using the newly developed strategy. As a result, the products of three cDNA clones were found to be novel N-myristoylated protein, and myristoylation-dependent specific intracellular localization was observed for two novel N-myristoylated proteins. Thus, the metabolic labeling in an insect cell-free protein synthesis system using bioorthogonal azide analogue of myristic acid was an effective strategy to identify novel N-myristoylated proteins from cDNA resources.
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Affiliation(s)
- Emi Takamitsu
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Kazuki Fukunaga
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Yusuke Iio
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Koko Moriya
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Toshihiko Utsumi
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan; Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi 753-8515, Japan.
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31
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Wang X, Boyken SE, Hu J, Xu X, Rimer RP, Shea MA, Shaw AS, Andreotti AH, Huang YH. Calmodulin and PI(3,4,5)P₃ cooperatively bind to the Itk pleckstrin homology domain to promote efficient calcium signaling and IL-17A production. Sci Signal 2014; 7:ra74. [PMID: 25097034 DOI: 10.1126/scisignal.2005147] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Precise regulation of the kinetics and magnitude of Ca(2+) signaling enables this signal to mediate diverse responses, such as cell migration, differentiation, vesicular trafficking, and cell death. We showed that the Ca(2+)-binding protein calmodulin (CaM) acted in a positive feedback loop to potentiate Ca(2+) signaling downstream of the Tec kinase family member Itk. Using NMR (nuclear magnetic resonance), we mapped CaM binding to two loops adjacent to the lipid-binding pocket within the Itk pleckstrin homology (PH) domain. The Itk PH domain bound synergistically to Ca(2+)/CaM and the lipid phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3], such that binding to Ca(2+)/CaM enhanced the binding to PI(3,4,5)P3 and vice versa. Disruption of CaM binding attenuated Itk recruitment to the membrane and diminished release of Ca(2+) from the endoplasmic reticulum. Moreover, disruption of this feedback loop abrogated Itk-dependent production of the proinflammatory cytokine IL-17A (interleukin-17A) by CD4(+) T cells. Additionally, we found that CaM associated with PH domains from other proteins, indicating that CaM may regulate other PH domain-containing proteins.
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Affiliation(s)
- Xinxin Wang
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Scott E Boyken
- Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Jiancheng Hu
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xiaolu Xu
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ryan P Rimer
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Madeline A Shea
- Department of Biochemistry, University of Iowa, Iowa City, IA 52242, USA
| | - Andrey S Shaw
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Amy H Andreotti
- Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Yina H Huang
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA. Department of Pathology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA. Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA.
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32
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Kursula P. The many structural faces of calmodulin: a multitasking molecular jackknife. Amino Acids 2014; 46:2295-304. [PMID: 25005783 DOI: 10.1007/s00726-014-1795-y] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 06/22/2014] [Indexed: 12/16/2022]
Abstract
Calmodulin (CaM) is a highly conserved protein and a crucial calcium sensor in eukaryotes. CaM is a regulator of hundreds of diverse target proteins. A wealth of studies has been carried out on the structure of CaM, both in the unliganded form and in complexes with target proteins and peptides. The outcome of these studies points toward a high propensity to attain various conformational states, depending on the binding partner. The purpose of this review is to provide examples of different conformations of CaM trapped in the crystal state. In addition, comparisons are made to corresponding studies in solution. The different CaM conformations in crystal structures are also compared based on the positions of the metal ions bound to their EF hands, in terms of distances, angles, and pseudo-torsion angles. Possible caveats and artifacts in CaM crystal structures are discussed, as well as the possibilities of trapping biologically relevant CaM conformations in the crystal state.
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Affiliation(s)
- Petri Kursula
- Faculty of Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland,
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33
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The Ever Changing Moods of Calmodulin: How Structural Plasticity Entails Transductional Adaptability. J Mol Biol 2014; 426:2717-35. [DOI: 10.1016/j.jmb.2014.05.016] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 05/14/2014] [Accepted: 05/16/2014] [Indexed: 11/20/2022]
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34
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Cao P, Zhang W, Gui W, Dong Y, Jiang T, Gong Y. Structural insights into the mechanism of calmodulin binding to death receptors. ACTA ACUST UNITED AC 2014; 70:1604-13. [DOI: 10.1107/s1399004714006919] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 03/28/2014] [Indexed: 11/10/2022]
Abstract
The death receptors Fas, p75NTRand DR6 are key components of extrinsically activated apoptosis. Characterization of how they interact with the adaptors is crucial in order to unravel the signalling mechanisms. However, the exact conformation that their intracellular death domain adopts upon binding downstream partners remains unclear. One model suggests that it adopts a typical compact fold, whilst a second model proposed an open conformation. Calmodulin (CaM), a major calcium sensor, has previously been reported to be one of the Fas adaptors that modulate apoptosis. This work reports that CaM also binds directly to the death domains of p75NTRand DR6, indicating that it serves as a common modulator of the death receptors. Two crystal structures of CaM in complexes with the corresponding binding regions of Fas and p75NTRare also reported. Interestingly, the precise CaM-binding sites were mapped to different regions: helix 1 in Fas and helix 5 in p75NTRand DR6. A novel 1–11 motif for CaM binding was observed in p75NTR. Modelling the complexes of CaM with full-length receptors reveals that the opening of the death domains would be essential in order to expose their binding sites for CaM. These results may facilitate understanding of the diverse functional repertoire of death receptors and CaM and provide further insights necessary for the design of potential therapeutic peptide agents.
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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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Vlach J, Samal AB, Saad JS. Solution structure of calmodulin bound to the binding domain of the HIV-1 matrix protein. J Biol Chem 2014; 289:8697-705. [PMID: 24500712 DOI: 10.1074/jbc.m113.543694] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Subcellular distribution of calmodulin (CaM) in human immunodeficiency virus type-1 (HIV-1)-infected cells is distinct from that observed in uninfected cells. CaM co-localizes and interacts with the HIV-1 Gag protein in the cytosol of infected cells. Although it has been shown that binding of Gag to CaM is mediated by the matrix (MA) domain, the structural details of this interaction are not known. We have recently shown that binding of CaM to MA induces a conformational change that triggers myristate exposure, and that the CaM-binding domain of MA is confined to a region spanning residues 8-43 (MA-(8-43)). Here, we present the NMR structure of CaM bound to MA-(8-43). Our data revealed that MA-(8-43), which contains a novel CaM-binding motif, binds to CaM in an antiparallel mode with the N-terminal helix (α1) anchored to the CaM C-terminal lobe, and the C-terminal helix (α2) of MA-(8-43) bound to the N-terminal lobe of CaM. The CaM protein preserves a semiextended conformation. Binding of MA-(8-43) to CaM is mediated by numerous hydrophobic interactions and stabilized by favorable electrostatic contacts. Our structural data are consistent with the findings that CaM induces unfolding of the MA protein to have access to helices α1 and α2. It is noteworthy that several MA residues involved in CaM binding have been previously implicated in membrane binding, envelope incorporation, and particle production. The present findings may ultimately help in identification of the functional role of CaM in HIV-1 replication.
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Affiliation(s)
- Jiri Vlach
- From the Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
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Prokosch V, Chiwitt C, Rose K, Thanos S. Deciphering proteins and their functions in the regenerating retina. Expert Rev Proteomics 2014; 7:775-95. [DOI: 10.1586/epr.10.47] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Moriya K, Nagatoshi K, Noriyasu Y, Okamura T, Takamitsu E, Suzuki T, Utsumi T. Protein N-myristoylation plays a critical role in the endoplasmic reticulum morphological change induced by overexpression of protein Lunapark, an integral membrane protein of the endoplasmic reticulum. PLoS One 2013; 8:e78235. [PMID: 24223779 PMCID: PMC3817238 DOI: 10.1371/journal.pone.0078235] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 09/10/2013] [Indexed: 11/18/2022] Open
Abstract
N-myristoylation of eukaryotic cellular proteins has been recognized as a modification that occurs mainly on cytoplasmic proteins. In this study, we examined the membrane localization, membrane integration, and intracellular localization of four recently identified human N-myristoylated proteins with predicted transmembrane domains. As a result, it was found that protein Lunapark, the human ortholog of yeast protein Lnp1p that has recently been found to be involved in network formation of the endoplasmic reticulum (ER), is an N-myristoylated polytopic integral membrane protein. Analysis of tumor necrosis factor-fusion proteins with each of the two putative transmembrane domains and their flanking regions of protein Lunapark revealed that transmembrane domain 1 and 2 functioned as type II signal anchor sequence and stop transfer sequence, respectively, and together generated a double-spanning integral membrane protein with an N-/C-terminal cytoplasmic orientation. Immunofluorescence staining of HEK293T cells transfected with a cDNA encoding protein Lunapark tagged with FLAG-tag at its C-terminus revealed that overexpressed protein Lunapark localized mainly to the peripheral ER and induced the formation of large polygonal tubular structures. Morphological changes in the ER induced by overexpressed protein Lunapark were significantly inhibited by the inhibition of protein N-myristoylation by means of replacing Gly2 with Ala. These results indicated that protein N-myristoylation plays a critical role in the ER morphological change induced by overexpression of protein Lunapark.
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Affiliation(s)
- Koko Moriya
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Kei Nagatoshi
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Yoshimi Noriyasu
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Tsuyoshi Okamura
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Emi Takamitsu
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
| | - Takashi Suzuki
- Clinical & Biotechnology Business Unit, Shimadzu Corporation, Kyoto, Japan
| | - Toshihiko Utsumi
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
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39
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Akgun B, Satija S, Nanda H, Pirrone GF, Shi X, Engen JR, Kent MS. Conformational transition of membrane-associated terminally acylated HIV-1 Nef. Structure 2013; 21:1822-33. [PMID: 24035710 DOI: 10.1016/j.str.2013.08.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Revised: 07/08/2013] [Accepted: 08/02/2013] [Indexed: 01/26/2023]
Abstract
Many proteins are posttranslationally modified by acylation targeting them to lipid membranes. While methods such as X-ray crystallography and nuclear magnetic resonance are available to determine the structure of folded proteins in solution, the precise position of folded domains relative to a membrane remains largely unknown. We used neutron and X-ray reflection methods to measure the displacement of the core domain of HIV Nef from lipid membranes upon insertion of the N-terminal myristate group. Nef is one of several HIV-1 accessory proteins and an essential factor in AIDS progression. Upon insertion of the myristate and residues from the N-terminal arm, Nef transitions from a closed-to-open conformation that positions the core domain 70 Å from the lipid headgroups. This work rules out previous speculation that the Nef core remains closely associated with the membrane to optimize interactions with the cytoplasmic domain of MHC-1.
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Affiliation(s)
- Bulent Akgun
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA; Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA; Department of Chemistry, Boğaziçi University, Bebek 34342, Istanbul, Turkey
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Tidow H, Nissen P. Structural diversity of calmodulin binding to its target sites. FEBS J 2013; 280:5551-65. [PMID: 23601118 DOI: 10.1111/febs.12296] [Citation(s) in RCA: 203] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 04/11/2013] [Accepted: 04/16/2013] [Indexed: 11/28/2022]
Abstract
Calmodulin (CaM) is a ubiquitous, highly conserved, eukaryotic protein that binds to and regulates a number of diverse target proteins involved in different functions such as metabolism, muscle contraction, apoptosis, memory, inflammation and the immune response. In this minireview, we analyze the large number of CaM-complex structures deposited in the Protein Data Bank (i.e. crystal and nuclear magnetic resonance structures) to gain insight into the structural diversity of CaM-binding sites and mechanisms, such as those for CaM-activated protein kinases and phosphatases, voltage-gated Ca(2+)-channels and the plasma membrane Ca(2+)-ATPase.
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Affiliation(s)
- Henning Tidow
- Centre for Membrane Pumps in Cells and Disease - PUMPkin, Aarhus University, Denmark; Department of Molecular Biology and Genetics, Aarhus University, Denmark
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Kato M, Aoyama T, Maeshima M. The Ca(2+) -binding protein PCaP2 located on the plasma membrane is involved in root hair development as a possible signal transducer. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 74:690-700. [PMID: 23445487 DOI: 10.1111/tpj.12155] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 02/15/2013] [Accepted: 02/21/2013] [Indexed: 05/10/2023]
Abstract
Plasma membrane-associated Ca(2+) -binding protein-2 (PCaP2) of Arabidopsis thaliana is a novel-type protein that binds to the Ca(2+) /calmodulin complex and phosphatidylinositol phosphates (PtdInsPs) as well as free Ca(2+) . Although the PCaP2 gene is predominantly expressed in root hair cells, it remains unknown how PCaP2 functions in root hair cells via binding to ligands. From biochemical analyses using purified PCaP2 and its variants, we found that the N-terminal basic domain with 23 amino acids (N23) is necessary and sufficient for binding to PtdInsPs and the Ca(2+) /calmodulin complex, and that the residual domain of PCaP2 binds to free Ca(2+) . In mutant analysis, a pcap2 knockdown line displayed longer root hairs than the wild-type. To examine the function of each domain in root hair cells, we over-expressed PCaP2 and its variants using the root hair cell-specific EXPANSIN A7 promoter. Transgenic lines over-expressing PCaP2, PCaP2(G2A) (second glycine substituted by alanine) and ∆23PCaP2 (lacking the N23 domain) exhibited abnormal branched and bulbous root hair cells, while over-expression of the N23 domain suppressed root hair emergence and elongation. The N23 domain was necessary and sufficient for the plasma membrane localization of GFP-tagged PCaP2. These results suggest that the N23 domain of PCaP2 negatively regulates root hair tip growth via processing Ca(2+) and PtdInsP signals on the plasma membrane, while the residual domain is involved in the polarization of cell expansion.
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Affiliation(s)
- Mariko Kato
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
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42
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Kropotova E, Klementiev B, Mosevitsky M. BASP1 and its N-end fragments (BNEMFs) dynamics in rat brain during development. Neurochem Res 2013; 38:1278-84. [PMID: 23579388 DOI: 10.1007/s11064-013-1035-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 03/26/2013] [Accepted: 03/28/2013] [Indexed: 10/27/2022]
Abstract
Protein BASP1 was discovered in brains of mammals and birds. In presynaptic area of synapses, BASP1 is attached to plasma membrane owing to N-terminal myristoylation as well as to the positively charged "effecter domain". BASP1 interactions with other proteins as well as with lipids contribute to membrane traffic, axon outgrowth and synaptic plasticity. BASP1 is present also in other tissues, where it was found not only in cytoplasm, but also in nucleus. Nuclear BASP1 suppresses activity of transcription factor WT1 and acts as tumor suppressor. BASP1 deficiency in a cell leads to its transformation. Previously it was shown that in BASP1 samples prepared from different animals and different tissues, six BASP1 N-end myristoylated fragments (BNEMFs) are present. Together, they amount to 30 % of the whole molecules. BNEMFs presence in different species and tissues demonstrates their physiological significance. However BNEMFs remain unexplored. In this paper, the time of appearance and dynamics of both BASP1 and BNEMFs during rat development from embryo to adult animals were determined. In rat brain, the amounts of all BASP1 forms per cell systematically increase during development and remain at the highest levels in adult animals. BNEMFs appear during embryogenesis non-simultaneously and accumulate with different dynamics. These results say for formation of six BNEMFs in the course of different processes and, possibly, using different mechanisms.
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Affiliation(s)
- Ekaterina Kropotova
- Division of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute, National Kurchatov Research Center, Leningrad District, 188300 Gatchina, Orlova Roscha, Russian Federation
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Protein N-myristoylation is required for cellular morphological changes induced by two formin family proteins, FMNL2 and FMNL3. Biosci Biotechnol Biochem 2012; 76:1201-9. [PMID: 22790947 DOI: 10.1271/bbb.120069] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The subcellular localization of 13 recently identified N-myristoylated proteins and the effects of overexpression of these proteins on cellular morphology were examined with the aim of understanding the physiological roles of the protein N-myristoylation that occurs on these proteins. Immunofluorescence staining of HEK293T cells transfected with cDNAs coding for the proteins revealed that most of them were associated with the plasma membrane or the membranes of intracellular compartments, and did not affect cellular morphology. However, two proteins, formin-like2 (FMNL2) and formin-like3 (FMNL3), both of them are members of the formin family of proteins, were associated mainly with the plasma membrane and induced significant cellular morphological changes. Inhibition of protein N-myristoylation by replacement of Gly2 with Ala or by the use of N-myristoylation inhibitor significantly inhibited membrane localization and the induction of cellular morphological changes, indicating that protein N-myristoylation plays critical roles in the cellular morphological changes induced by FMNL2 and FMNL3.
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The myristate moiety and amino terminus of vaccinia virus l1 constitute a bipartite functional region needed for entry. J Virol 2012; 86:5437-51. [PMID: 22398293 DOI: 10.1128/jvi.06703-11] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Vaccinia virus (VACV) L1 is a myristoylated envelope protein which is required for cell entry and the fusion of infected cells. L1 associates with members of the entry-fusion complex (EFC), but its specific role in entry has not been delineated. We recently demonstrated (Foo CH, et al., Virology 385:368-382, 2009) that soluble L1 binds to cells and blocks entry, suggesting that L1 serves as the receptor-binding protein for entry. Our goal is to identify the structural domains of L1 which are essential for its functions in VACV entry. We hypothesized that the myristate and the conserved residues at the N terminus of L1 are critical for entry. To test our hypothesis, we generated mutants in the N terminus of L1 and used a complementation assay to evaluate their ability to rescue infectivity. We also assessed the myristoylation efficiency of the mutants and their ability to interact with the EFC. We found that the N terminus of L1 constitutes a region that is critical for the infectivity of VACV and for myristoylation. At the same time, the nonmyristoylated mutants were incorporated into mature virions, suggesting that the myristate is not required for the association of L1 with the viral membrane. Although some of the mutants exhibited altered structural conformations, two mutants with impaired infectivity were similar in conformation to wild-type L1. Importantly, these two mutants, with changes at A4 and A5, undergo myristoylation. Overall, our results imply dual differential roles for myristate and the amino acids at the N terminus of L1. We propose a myristoyl switch model to describe how L1 functions.
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Ghanam RH, Samal AB, Fernandez TF, Saad JS. Role of the HIV-1 Matrix Protein in Gag Intracellular Trafficking and Targeting to the Plasma Membrane for Virus Assembly. Front Microbiol 2012; 3:55. [PMID: 22363329 PMCID: PMC3281212 DOI: 10.3389/fmicb.2012.00055] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 02/01/2012] [Indexed: 11/13/2022] Open
Abstract
Human immunodeficiency virus type-1 (HIV-1) encodes a polypeptide called Gag that is able to form virus-like particles in vitro in the absence of any cellular or viral constituents. During the late phase of the HIV-1 infection, Gag polyproteins are transported to the plasma membrane (PM) for assembly. In the past two decades, in vivo, in vitro, and structural studies have shown that Gag trafficking and targeting to the PM are orchestrated events that are dependent on multiple factors including cellular proteins and specific membrane lipids. The matrix (MA) domain of Gag has been the focus of these studies as it appears to be engaged in multiple intracellular interactions that are suggested to be critical for virus assembly and replication. The interaction between Gag and the PM is perhaps the most understood. It is now established that the ultimate localization of Gag on punctate sites on the PM is mediated by specific interactions between the MA domain of Gag and phosphatidylinositol-4,5-bisphosphate [PI(4,5)P(2)], a minor lipid localized on the inner leaflet of the PM. Structure-based studies revealed that binding of PI(4,5)P(2) to MA induces minor conformational changes, leading to exposure of the myristyl (myr) group. Exposure of the myr group is also triggered by binding of calmodulin, enhanced by factors that promote protein self-association like the capsid domain of Gag, and is modulated by pH. Despite the steady progress in defining both the viral and cellular determinants of retroviral assembly and release, Gag's intracellular interactions and trafficking to its assembly sites in the infected cell are poorly understood. In this review, we summarize the current understanding of the structural and functional role of MA in HIV replication.
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Affiliation(s)
- Ruba H Ghanam
- Department of Microbiology, University of Alabama at Birmingham Birmingham, AL, USA
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Samal AB, Ghanam RH, Fernandez TF, Monroe EB, Saad JS. NMR, biophysical, and biochemical studies reveal the minimal Calmodulin binding domain of the HIV-1 matrix protein. J Biol Chem 2011; 286:33533-43. [PMID: 21799007 DOI: 10.1074/jbc.m111.273623] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Subcellular distribution of Calmodulin (CaM) in human immunodeficiency virus type-1 (HIV-1)-infected cells is distinct from that observed in uninfected cells. CaM has been shown to interact and co-localize with the HIV-1 Gag protein in infected cells. However, the precise molecular mechanism of this interaction is not known. Binding of Gag to CaM is dependent on calcium and is mediated by the N-terminal-myristoylated matrix (myr(+)MA) domain. We have recently shown that CaM binding induces a conformational change in the MA protein, triggering exposure of the myristate group. To unravel the molecular mechanism of CaM-MA interaction and to identify the minimal CaM binding domain of MA, we devised multiple approaches utilizing NMR, biochemical, and biophysical methods. Short peptides derived from the MA protein have been examined. Our data revealed that whereas peptides spanning residues 11-28 (MA-(11-28)) and 31-46 (MA-(31-46)) appear to bind preferentially to the C-terminal lobe of CaM, a peptide comprising residues 11-46 (MA-(11-46)) appears to engage both domains of CaM. Limited proteolysis data conducted on the MA-CaM complex yielded a MA peptide (residues 8-43) that is protected by CaM and resistant to proteolysis. MA-(8-43) binds to CaM with a very high affinity (dissociation constant = 25 nm) and in a manner that is similar to that observed for the full-length MA protein. The present findings provide new insights on how MA interacts with CaM that may ultimately help in identification of the functional role of CaM-Gag interactions in the HIV replication cycle.
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Affiliation(s)
- Alexandra B Samal
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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Bhagatji P, Leventis R, Rich R, Lin CJ, Silvius JR. Multiple cellular proteins modulate the dynamics of K-ras association with the plasma membrane. Biophys J 2011; 99:3327-35. [PMID: 21081081 DOI: 10.1016/j.bpj.2010.10.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Revised: 09/21/2010] [Accepted: 10/04/2010] [Indexed: 10/18/2022] Open
Abstract
Although specific proteins have been identified that regulate the membrane association and facilitate intracellular transport of prenylated Rho- and Rab-family proteins, it is not known whether cellular proteins fulfill similar roles for other prenylated species, such as Ras-family proteins. We used a previously described method to evaluate how several cellular proteins, previously identified as potential binding partners (but not effectors) of K-ras4B, influence the dynamics of K-ras association with the plasma membrane. Overexpression of either PDEδ or PRA1 enhances, whereas knockdown of either protein reduces, the rate of dissociation of K-ras from the plasma membrane. Inhibition of calmodulin likewise reduces the rate of K-ras dissociation from the plasma membrane, in this case in a manner specific for the activated form of K-ras. By contrast, galectin-3 specifically reduces the rate of plasma membrane dissociation of activated K-ras, an effect that is blocked by the K-ras antagonist farnesylthiosalicylic acid (salirasib). Multiple cellular proteins thus control the dynamics of membrane association and intercompartmental movement of K-ras to an important degree even under basal cellular conditions.
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Affiliation(s)
- Pinkesh Bhagatji
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
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48
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Ghanam RH, Fernandez TF, Fledderman EL, Saad JS. Binding of calmodulin to the HIV-1 matrix protein triggers myristate exposure. J Biol Chem 2010; 285:41911-20. [PMID: 20956522 PMCID: PMC3009918 DOI: 10.1074/jbc.m110.179093] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 10/12/2010] [Indexed: 01/16/2023] Open
Abstract
Steady progress has been made in defining both the viral and cellular determinants of retroviral assembly and release. Although it is widely accepted that targeting of the Gag polypeptide to the plasma membrane is critical for proper assembly of HIV-1, the intracellular interactions and trafficking of Gag to its assembly sites in the infected cell are poorly understood. HIV-1 Gag was shown to interact and co-localize with calmodulin (CaM), a ubiquitous and highly conserved Ca(2+)-binding protein expressed in all eukaryotic cells, and is implicated in a variety of cellular functions. Binding of HIV-1 Gag to CaM is dependent on calcium and is mediated by the N-terminally myristoylated matrix (myr(+)MA) domain. Herein, we demonstrate that CaM binds to myr(+)MA with a dissociation constant (K(d)) of ∼2 μm and 1:1 stoichiometry. Strikingly, our data revealed that CaM binding to MA induces the extrusion of the myr group. However, in contrast to all known examples of CaM-binding myristoylated proteins, our data show that the myr group is exposed to solvent and not involved in CaM binding. The interactions between CaM and myr(+)MA are endothermic and entropically driven, suggesting that hydrophobic contacts are critical for binding. As revealed by NMR data, both CaM and MA appear to engage substantial regions and/or undergo significant conformational changes upon binding. We believe that our findings will provide new insights on how Gag may interact with CaM during the HIV replication cycle.
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Affiliation(s)
- Ruba H. Ghanam
- From the Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Timothy F. Fernandez
- From the Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Emily L. Fledderman
- From the Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Jamil S. Saad
- From the Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294
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Kato M, Nagasaki-Takeuchi N, Ide Y, Tomioka R, Maeshima M. PCaPs, possible regulators of PtdInsP signals on plasma membrane. PLANT SIGNALING & BEHAVIOR 2010; 5:848-50. [PMID: 20448467 PMCID: PMC3014536 DOI: 10.4161/psb.5.7.11825] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
In plants, Ca(2+), phosphatidylinositol phosphates (PtdInsPs) and inositol phosphates are major components of intracellular signaling. Several kinds of proteins and enzymes, such as calmodulin (CaM), protein kinase, protein phosphatase, and the Ca(2+) channel, mediate the signaling. Two new Ca(2+)-binding proteins were identified from Arabidopsis thaliana and named PCaP1 and PCaP2 [plasma membrane (PM)-associated Ca(2+) (cation)-binding protein 1 and 2]. PCaP1 has an intrinsically disordered region in the central and C-terminal parts. The PCaP1 gene is expressed in most tissues and the PCaP2 gene is expressed predominantly in root hairs and pollen tubes. We recently demonstrated that these proteins are N-myristoylated, stably anchored in the PM, and are bound with phosphatidylinositol phosphates, especially PtdInsP2s. Here we propose a model for the switching mechanism of Ca (2+)-signaling mediated by PtdInsPs. Ca(2+) forms a complex with CaM (Ca(2+)-CaM) when there is an increase in the cytosol free Ca(2+). The binding of PCaPs with Ca(2+)-CaM causes PCaPs to release PtdInsPs. Until the release of PtdInsPs, the signaling is kept in the resting state.
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Affiliation(s)
- Mariko Kato
- Graduate School of Bioagricultural Sciences; Nagoya University, Nagoya, Japan
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Kato M, Nagasaki-Takeuchi N, Ide Y, Maeshima M. An Arabidopsis hydrophilic Ca2(+) -binding protein with a PEVK-rich domain, PCaP2, is associated with the plasma membrane and interacts with calmodulin and phosphatidylinositol phosphates. PLANT & CELL PHYSIOLOGY 2010; 51:366-79. [PMID: 20061304 DOI: 10.1093/pcp/pcq003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We found a new hydrophilic protein in Arabidopsis thaliana. Real-time PCR demonstrated that the protein was expressed in roots. Histochemical analysis of promoter-beta-glucuronidase fusions demonstrated its extensive expression in root hairs. The protein is rich in proline, glutamate, valine and lysine residues (PEVK-rich domain), and bound Ca(2+) even in the presence of Mg(2+) and K(+) when examined by the (45)Ca overlay assay. Treatment of seedlings with K(+), Mn(2+), Zn(2+), Na(+), ABA and gibberellic acid, and cold and drought stresses enhanced the transcription. Expression of the protein linked to green fluorescent protein in A. thaliana showed its plasma membrane localization and cell-specific expression in the epidermal cells including root hairs and the elongating pollen tubes. Therefore, we named the protein PCaP2 (plasma membrane-associated Ca(2+)-binding protein-2). The substitution of glycine at position 2 with alanine resulted in cytoplasmic localization of PCaP2. These results and the N-terminal characteristic motif suggest that PCaP2 is N-myristoylated at Gly2. We examined the capacity for binding to phosphatidylinositol phosphates (PtdInsPs), and found that PCaP2 interacts strongly with PtdIns(3,5)P(2), PtdIns(4,5)P(2) and PtdIns(3,4,5)P(3), and weakly with PtdIns(3,4)P(2). Furthermore, calmodulin was associated with PCaP2 in a Ca(2+)-dependent manner, and its association weakened the interaction of PCaP2 with PtdInsPs. These results indicate that PCaP2 is involved in intracellular signaling through interaction with PtdInsPs and calmodulin in growing root hairs. PCaP2 was previously reported as microtubule-associated protein-18. We discuss the physiological roles of PCaP2 in relation to microtubules in cells.
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Affiliation(s)
- Mariko Kato
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan
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