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Camara A, Chugh H, George A, Dolidze L, Ryu K, Holly KJ, Flaherty DP, Mattoo S. Discovery and validation of a novel inhibitor of HYPE-mediated AMPylation. Cell Stress Chaperones 2024; 29:404-424. [PMID: 38599565 PMCID: PMC11053294 DOI: 10.1016/j.cstres.2024.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/03/2024] [Accepted: 04/03/2024] [Indexed: 04/12/2024] Open
Abstract
Adenosyl monophosphate (AMP)ylation (the covalent transfer of an AMP from Adenosine Triphosphate (ATP) onto a target protein) is catalyzed by the human enzyme Huntingtin Yeast Interacting Partner E (HYPE)/FicD to regulate its substrate, the heat shock chaperone binding immunoglobulin protein (BiP). HYPE-mediated AMPylation of BiP is critical for maintaining proteostasis in the endoplasmic reticulum and mounting a unfolded protein response in times of proteostatic imbalance. Thus, manipulating HYPE's enzymatic activity is a key therapeutic strategy toward the treatment of various protein misfolding diseases, including neuropathy and early-onset diabetes associated with two recently identified clinical mutations of HYPE. Herein, we present an optimized, fluorescence polarization-based, high-throughput screening (HTS) assay to discover activators and inhibitors of HYPE-mediated AMPylation. After challenging our HTS assay with over 30,000 compounds, we discovered a novel AMPylase inhibitor, I2.10. We also determined a low micromolar IC50 for I2.10 and employed biorthogonal counter-screens to validate its efficacy against HYPE's AMPylation of BiP. Further, we report low cytotoxicity of I2.10 on human cell lines. We thus established an optimized, high-quality HTS assay amenable to tracking HYPE's enzymatic activity at scale, and provided the first novel small-molecule inhibitor capable of perturbing HYPE-directed AMPylation of BiP in vitro. Our HTS assay and I2.10 compound serve as a platform for further development of HYPE-specific small-molecule therapeutics.
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Affiliation(s)
- Ali Camara
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Heerak Chugh
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA; Drug Discovery and Development Laboratory, Department of Chemistry, University of Delhi, Delhi, India
| | - Alyssa George
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Lukas Dolidze
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Kevin Ryu
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Katrina J Holly
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, USA
| | - Daniel P Flaherty
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, USA
| | - Seema Mattoo
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, USA; Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA.
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2
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Léger C, Pitard I, Sadi M, Carvalho N, Brier S, Mechaly A, Raoux-Barbot D, Davi M, Hoos S, Weber P, Vachette P, Durand D, Haouz A, Guijarro JI, Ladant D, Chenal A. Dynamics and structural changes of calmodulin upon interaction with the antagonist calmidazolium. BMC Biol 2022; 20:176. [PMID: 35945584 PMCID: PMC9361521 DOI: 10.1186/s12915-022-01381-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/29/2022] [Indexed: 11/11/2022] Open
Abstract
Background Calmodulin (CaM) is an evolutionarily conserved eukaryotic multifunctional protein that functions as the major sensor of intracellular calcium signaling. Its calcium-modulated function regulates the activity of numerous effector proteins involved in a variety of physiological processes in diverse organs, from proliferation and apoptosis, to memory and immune responses. Due to the pleiotropic roles of CaM in normal and pathological cell functions, CaM antagonists are needed for fundamental studies as well as for potential therapeutic applications. Calmidazolium (CDZ) is a potent small molecule antagonist of CaM and one the most widely used inhibitors of CaM in cell biology. Yet, CDZ, as all other CaM antagonists described thus far, also affects additional cellular targets and its lack of selectivity hinders its application for dissecting calcium/CaM signaling. A better understanding of CaM:CDZ interaction is key to design analogs with improved selectivity. Here, we report a molecular characterization of CaM:CDZ complexes using an integrative structural biology approach combining SEC-SAXS, X-ray crystallography, HDX-MS, and NMR. Results We provide evidence that binding of a single molecule of CDZ induces an open-to-closed conformational reorientation of the two domains of CaM and results in a strong stabilization of its structural elements associated with a reduction of protein dynamics over a large time range. These CDZ-triggered CaM changes mimic those induced by CaM-binding peptides derived from physiological protein targets, despite their distinct chemical natures. CaM residues in close contact with CDZ and involved in the stabilization of the CaM:CDZ complex have been identified. Conclusion Our results provide molecular insights into CDZ-induced dynamics and structural changes of CaM leading to its inhibition and open the way to the rational design of more selective CaM antagonists. Graphical abstract Calmidazolium is a potent and widely used inhibitor of calmodulin, a major mediator of calcium-signaling in eukaryotic cells. Structural characterization of calmidazolium-binding to calmodulin reveals that it triggers open-to-closed conformational changes similar to those induced by calmodulin-binding peptides derived from enzyme targets. These results provide molecular insights into CDZ-induced dynamics and structural changes of CaM leading to its inhibition and open the way to the rational design of more selective CaM antagonists.![]() Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01381-5.
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Affiliation(s)
- Corentin Léger
- Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris, 75015, France
| | - Irène Pitard
- Biological NMR and HDX-MS Technological Platform, CNRS UMR3528, Université Paris Cité, Institut Pasteur, Paris, 75015, France
| | - Mirko Sadi
- Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris, 75015, France.,Université Paris Cité, Paris, France
| | - Nicolas Carvalho
- Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris, 75015, France.,Université Paris Cité, Paris, France
| | - Sébastien Brier
- Biological NMR and HDX-MS Technological Platform, CNRS UMR3528, Université Paris Cité, Institut Pasteur, Paris, 75015, France
| | - Ariel Mechaly
- Plate-forme de Cristallographie-C2RT, Université Paris Cité, CNRS UMR3528, Institut Pasteur, Paris, France
| | - Dorothée Raoux-Barbot
- Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris, 75015, France
| | - Maryline Davi
- Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris, 75015, France
| | - Sylviane Hoos
- Plateforme de Biophysique Moléculaire, Université Paris Cité, CNRS UMR3528, Institut Pasteur, Paris, France
| | - Patrick Weber
- Plate-forme de Cristallographie-C2RT, Université Paris Cité, CNRS UMR3528, Institut Pasteur, Paris, France
| | - Patrice Vachette
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Dominique Durand
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Ahmed Haouz
- Plate-forme de Cristallographie-C2RT, Université Paris Cité, CNRS UMR3528, Institut Pasteur, Paris, France
| | - J Iñaki Guijarro
- Biological NMR and HDX-MS Technological Platform, CNRS UMR3528, Université Paris Cité, Institut Pasteur, Paris, 75015, France
| | - Daniel Ladant
- Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris, 75015, France.
| | - Alexandre Chenal
- Biochemistry of Macromolecular Interactions Unit, Department of Structural Biology and Chemistry, CNRS UMR3528, Institut Pasteur, Paris, 75015, France.
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3
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Kurian SM, Lichius A, Read ND. Ca2+ Signalling Differentially Regulates Germ-Tube Formation and Cell Fusion in Fusarium oxysporum. J Fungi (Basel) 2022; 8:jof8010090. [PMID: 35050029 PMCID: PMC8780837 DOI: 10.3390/jof8010090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/12/2022] [Accepted: 01/14/2022] [Indexed: 11/16/2022] Open
Abstract
Fusarium oxysporum is an important plant pathogen and an emerging opportunistic human pathogen. Germination of conidial spores and their fusion via conidial anastomosis tubes (CATs) are significant events during colony establishment in culture and on host plants and, hence, very likely on human epithelia. CAT fusion exhibited by conidial germlings of Fusarium species has been postulated to facilitate mitotic recombination, leading to heterokaryon formation and strains with varied genotypes and potentially increased virulence. Ca2+ signalling is key to many of the important physiological processes in filamentous fungi. Here, we tested pharmacological agents with defined modes of action in modulation of the mammalian Ca2+ signalling machinery for their effect on germination and CAT-mediated cell fusion in F. oxysporum. We found various drug-specific and dose-dependent effects. Inhibition of calcineurin by FK506 or cyclosporin A, as well as chelation of extracellular Ca2+ by BAPTA, exclusively inhibit CAT induction but not germ-tube formation. On the other hand, inhibition of Ca2+ channels by verapamil, calmodulin inhibition by calmidazolium, and inhibition of mitochondrial calcium uniporters by RU360 inhibited both CAT induction and germ-tube formation. Thapsigargin, an inhibitor of mammalian sarco/endoplasmic reticulum Ca2+ ATPase (SERCA), partially inhibited CAT induction but had no effect on germ-tube formation. These results provide initial evidence for morphologically defining roles of Ca2+-signalling components in the early developmental stages of F. oxysporum colony establishment—most notably, the indication that calcium ions act as self-signalling molecules in this process. Our findings contribute an important first step towards the identification of Ca2+ inhibitors with fungas-specific effects that could be exploited for the treatment of infected plants and humans.
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Affiliation(s)
- Smija M. Kurian
- Manchester Fungal Infection Group, University of Manchester, Manchester M13 9NT, UK;
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
- Correspondence:
| | - Alexander Lichius
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria;
| | - Nick D. Read
- Manchester Fungal Infection Group, University of Manchester, Manchester M13 9NT, UK;
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4
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Camara A, George A, Hebner E, Mahmood A, Paluru J, Mattoo S. A Fluorescence Polarization-Based High-Throughput Screen to Identify the First Small-Molecule Modulators of the Human Adenylyltransferase HYPE/FICD. Int J Mol Sci 2020; 21:E7128. [PMID: 32992526 PMCID: PMC7582957 DOI: 10.3390/ijms21197128] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/24/2020] [Accepted: 09/25/2020] [Indexed: 11/16/2022] Open
Abstract
The covalent transfer of the AMP portion of ATP onto a target protein-termed adenylylation or AMPylation-by the human Fic protein HYPE/FICD has recently garnered attention as a key regulatory mechanism in endoplasmic reticulum homeostasis, neurodegeneration, and neurogenesis. As a central player in such critical cellular events, high-throughput screening (HTS) efforts targeting HYPE-mediated AMPylation warrant investigation. Herein, we present a dual HTS assay for the simultaneous identification of small-molecule activators and inhibitors of HYPE AMPylation. Employing the fluorescence polarization of an ATP analog fluorophore-Fl-ATP-we developed and optimized an efficient, robust assay that monitors HYPE autoAMPylation and is amenable to automated, high-throughput processing of diverse chemical libraries. Challenging our pilot screen with compounds from the LOPAC, Spectrum, MEGx, and NATx libraries yielded 0.3% and 1% hit rates for HYPE activators and inhibitors, respectively. Further, these hits were assessed for dose-dependency and validated via orthogonal biochemical AMPylation assays. We thus present a high-quality HTS assay suitable for tracking HYPE's enzymatic activity, and the resultant first small-molecule manipulators of HYPE-promoted autoAMPylation.
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Affiliation(s)
- Ali Camara
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; (A.C.); (A.G.); (E.H.); (A.M.)
| | - Alyssa George
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; (A.C.); (A.G.); (E.H.); (A.M.)
| | - Evan Hebner
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; (A.C.); (A.G.); (E.H.); (A.M.)
| | - Anika Mahmood
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; (A.C.); (A.G.); (E.H.); (A.M.)
| | - Jashun Paluru
- William Henry Harrison High School, West Lafayette, IN 47906, USA;
| | - Seema Mattoo
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA; (A.C.); (A.G.); (E.H.); (A.M.)
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA
- Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
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5
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Breitholtz M, Ivanov P, Ek K, Gorokhova E. Calmodulin inhibition as a mode of action of antifungal imidazole pharmaceuticals in non-target organisms. Toxicol Res (Camb) 2020; 9:425-430. [PMID: 32905197 PMCID: PMC7467228 DOI: 10.1093/toxres/tfaa039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 05/06/2020] [Accepted: 05/15/2020] [Indexed: 01/08/2023] Open
Abstract
To improve assessment of risks associated with pharmaceutical contamination of the environment, it is crucial to understand effects and mode of action of drugs in non-target species. The evidence is accumulating that species with well-conserved drug targets are prone to be at risk when exposed to pharmaceuticals. An interesting group of pharmaceuticals released into the environment is imidazoles, antifungal agents with inhibition of ergosterol synthesis as a primary mode of action in fungi. However, imidazoles have also been identified as competitive antagonists of calmodulin (CaM), a calcium-binding protein with phylogenetically conserved structure and function. Therefore, imidazoles would act as CaM inhibitors in various organisms, including those with limited capacity to synthesize sterols, such as arthropods. We hypothesized that effects observed in crustaceans exposed to imidazoles are related to the CaM inhibition and CaM-dependent nitric oxide (NO) synthesis. To test this hypothesis, we measured (i) CaM levels and its gene expression, (ii) NO accumulation and (iii) gene expression of NO synthase (NOS1 and NOS2), in the cladoceran Daphnia magna exposed to miconazole, a model imidazole drug. Whereas significantly increased CaM gene expression and its cellular allocation were observed, supporting the hypothesized mode of action, no changes occurred in either NO synthase expression or NO levels in the exposed animals. These findings suggest that CaM inhibition by miconazole leads to protein overexpression that compensates for the loss in the protein activity, with no measurable downstream effects on NO pathways. The inhibition of CaM in D. magna may have implications for effect assessment of exposure to mixtures of imidazoles in aquatic non-target species.
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Affiliation(s)
- Magnus Breitholtz
- Department of Environmental Science and Analytical Chemistry , Stockholm University, SE-106 91, Sweden
| | - Pavel Ivanov
- Department of Environmental Science and Analytical Chemistry , Stockholm University, SE-106 91, Sweden
| | - Karin Ek
- Department of Environmental Science and Analytical Chemistry , Stockholm University, SE-106 91, Sweden
| | - Elena Gorokhova
- Department of Environmental Science and Analytical Chemistry , Stockholm University, SE-106 91, Sweden
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6
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Baik JY, Park EYJ, So I. Ca 2+/calmodulin-dependent regulation of polycystic kidney disease 2-like-1 by binding at C-terminal domain. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2020; 24:277-286. [PMID: 32392919 PMCID: PMC7193909 DOI: 10.4196/kjpp.2020.24.3.277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/20/2020] [Accepted: 02/26/2020] [Indexed: 11/27/2022]
Abstract
Polycystic kidney disease 2-like-1 (PKD2L1), also known as polycystin-L or TRPP3, is a non-selective cation channel that regulates intracellular calcium concentration. Calmodulin (CaM) is a calcium binding protein, consisting of N-lobe and C-lobe with two calcium binding EF-hands in each lobe. In previous study, we confirmed that CaM is associated with desensitization of PKD2L1 and that CaM N-lobe and PKD2L1 EF-hand specifically are involved. However, the CaM-binding domain (CaMBD) and its inhibitory mechanism of PKD2L1 have not been identified. In order to identify CaM-binding anchor residue of PKD2L1, single mutants of putative CaMBD and EF-hand deletion mutants were generated. The current changes of the mutants were recorded with whole-cell patch clamp. The calmidazolium (CMZ), a calmodulin inhibitor, was used under different concentrations of intracellular. Among the mutants that showed similar or higher basal currents with that of the PKD2L1 wild type, L593A showed little change in current induced by CMZ. Co-expression of L593A with CaM attenuated the inhibitory effect of PKD2L1 by CaM. In the previous study it was inferred that CaM C-lobe inhibits channels by binding to PKD2L1 at 16 nM calcium concentration and CaM N-lobe at 100 nM. Based on the results at 16 nM calcium concentration condition, this study suggests that CaM C-lobe binds to Leu-593, which can be a CaM C-lobe anchor residue, to regulate channel activity. Taken together, our results provide a model for the regulation of PKD2L1 channel activity by CaM.
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Affiliation(s)
- Julia Young Baik
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Eunice Yon June Park
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Insuk So
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
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7
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Pacini S, Montali M, Mazziotta F, Schifone CP, Macchia L, Carnicelli V, Panvini FM, Barachini S, Notarfranchi L, Previti GB, Buda G, Petrini M. Mesangiogenic progenitor cells are forced toward the angiogenic fate, in multiple myeloma. Oncotarget 2019; 10:6781-6790. [PMID: 31827721 PMCID: PMC6887577 DOI: 10.18632/oncotarget.27285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/04/2019] [Indexed: 11/25/2022] Open
Abstract
Multiple myeloma (MM) progresses mainly in the bone marrow where the involvement of a specific microenvironment plays a critical role in maintaining plasma cell growth, spread, and survival. In active disease, the switch from a pre-vascular/non-active phase to a vascular phase is coupled with the impairment of bone turnover. Previously, we have isolated Mesangiogenic Progenitor Cells (MPCs), a bone marrow population that showed mesengenic and angiogenic potential, both in vitro and in vivo. MPC differentiation into musculoskeletal tissue and their ability of sprouting angiogenesis are mutually exclusive, suggesting a role in the imbalancing of the microenvironment in multiple myeloma. MPCs from 32 bone marrow samples of multiple myeloma and 23 non-hematological patients were compared in terms of frequency, phenotype, mesengenic/angiogenic potential, and gene expression profile. Defective osteogenesis was recorded for MM-derived MPCs that showed longer angiogenic sprouting distances respect to non-hematological MPCs, retaining this capability after mesengenic induction. This altered MPCs differentiation potential was not detected in asymptomatic myelomatous disease. These in vitro experiments are suggestive of a forced angiogenic fate in MPCs isolated from MM patients, which also showed increased sprouting activity. Taking together our results suggest a possible role of these cells in the “angiogenic switch” in the MM micro-environment.
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Affiliation(s)
- Simone Pacini
- Department of Clinical and Experimental Medicine, Hematology Division, University of Pisa, Pisa, Italy
| | - Marina Montali
- Department of Clinical and Experimental Medicine, Hematology Division, University of Pisa, Pisa, Italy
| | | | - Claudia P Schifone
- Department of Clinical and Experimental Medicine, Hematology Division, University of Pisa, Pisa, Italy
| | - Lucia Macchia
- Department of Laboratory Medicine, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy
| | - Vittoria Carnicelli
- Department of Surgical, Medical, and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| | - Francesca M Panvini
- Institute of Life Sciences, Sant'Anna School of Advanced Studies, Pisa, Italy
| | - Serena Barachini
- Department of Clinical and Experimental Medicine, Hematology Division, University of Pisa, Pisa, Italy
| | - Laura Notarfranchi
- Department of Medicine and Surgery, Hematology Division, University of Parma, Parma, Italy
| | | | - Gabriele Buda
- Department of Clinical and Experimental Medicine, Hematology Division, University of Pisa, Pisa, Italy
| | - Mario Petrini
- Department of Clinical and Experimental Medicine, Hematology Division, University of Pisa, Pisa, Italy
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8
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Park EYJ, Baik JY, Kwak M, So I. The role of calmodulin in regulating calcium-permeable PKD2L1 channel activity. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2019; 23:219-227. [PMID: 31080352 PMCID: PMC6488707 DOI: 10.4196/kjpp.2019.23.3.219] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 11/15/2022]
Abstract
Polycystic kidney disease 2-like-1 (PKD2L1), polycystin-L or transient receptor potential polycystin 3 (TRPP3) is a TRP superfamily member. It is a calcium-permeable non-selective cation channel that regulates intracellular calcium concentration and thereby calcium signaling. Although the calmodulin (CaM) inhibitor, calmidazolium, is an activator of the PKD2L1 channel, the activating mechanism remains unclear. The purpose of this study is to clarify whether CaM takes part in the regulation of the PKD2L1 channel, and if so, how. With patch clamp techniques, we observed the current amplitudes of PKD2L1 significantly reduced when coexpressed with CaM and CaMΔN. This result suggests that the N-lobe of CaM carries a more crucial role in regulating PKD2L1 and guides us into our next question on the different functions of two lobes of CaM. We also identified the predicted CaM binding site, and generated deletion and truncation mutants. The mutants showed significant reduction in currents losing PKD2L1 current-voltage curve, suggesting that the C-terminal region from 590 to 600 is crucial for maintaining the functionality of the PKD2L1 channel. With PKD2L1608Stop mutant showing increased current amplitudes, we further examined the functional importance of EF-hand domain. Along with co-expression of CaM, ΔEF-hand mutant also showed significant changes in current amplitudes and potentiation time. Our findings suggest that there is a constitutive inhibition of EF-hand and binding of CaM C-lobe on the channel in low calcium concentration. At higher calcium concentration, calcium ions occupy the N-lobe as well as the EF-hand domain, allowing the two to compete to bind to the channel.
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Affiliation(s)
- Eunice Yon June Park
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Julia Young Baik
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Misun Kwak
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Insuk So
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
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9
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Singh V, Deepak RNVK, Sengupta B, Joshi AS, Fan H, Sen P, Thakur AK. Calmidazolium Chloride and Its Complex with Serum Albumin Prevent Huntingtin Exon1 Aggregation. Mol Pharm 2018; 15:3356-3368. [PMID: 29979597 DOI: 10.1021/acs.molpharmaceut.8b00380] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Huntington's disease (HD) is a genetic disorder caused by a CAG expansion mutation in Huntingtin gene leading to polyglutamine (polyQ) expansion in the N-terminus side of Huntingtin (Httex1) protein. Neurodegeneration in HD is linked to aggregates formed by Httex1 bearing an expanded polyQ. Initiation and elongation steps of Httex1 aggregation are potential target steps for the discovery of therapeutic molecules for HD, which is currently untreatable. Here we report Httex1 aggregation inhibition by calmidazolium chloride (CLC) by acting on the initial aggregation event. Because it is hydrophobic, CLC was adsorbed to the vial surface and could not sustain an inhibition effect for a longer duration. The use of bovine serum albumin (BSA) prevented CLC adsorption by forming a BSA-CLC complex. This complex showed improved Httex1 aggregation inhibition by interacting with the aggregation initiator, the NT17 part of Httex1. Furthermore, biocompatible CLC-loaded BSA nanoparticles were made which reduced the polyQ aggregates in HD-150Q cells.
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Affiliation(s)
- Virender Singh
- Biological Sciences and Bioengineering , Indian Institute of Technology Kanpur , Kanpur 208016 , India
| | | | - Bhaswati Sengupta
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208016 , India
| | - Abhayraj S Joshi
- Biological Sciences and Bioengineering , Indian Institute of Technology Kanpur , Kanpur 208016 , India
| | - Hao Fan
- Bioinformatics Institute , 30 Biopolis Street, Matrix #07-01 , Singapore 138671.,Department of Biological Sciences , National University of Singapore , Singapore 117545
| | - Pratik Sen
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208016 , India
| | - Ashwani Kumar Thakur
- Biological Sciences and Bioengineering , Indian Institute of Technology Kanpur , Kanpur 208016 , India
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10
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Park EYJ, Kwak M, Ha K, So I. Identification of clustered phosphorylation sites in PKD2L1: how PKD2L1 channel activation is regulated by cyclic adenosine monophosphate signaling pathway. Pflugers Arch 2017; 470:505-516. [PMID: 29230552 DOI: 10.1007/s00424-017-2095-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/21/2017] [Accepted: 12/01/2017] [Indexed: 01/01/2023]
Abstract
Polycystic kidney disease 2-like-1 (PKD2L1), or polycystin-L or TRPP2, formerly TRPP3, is a transient receptor potential (TRP) superfamily member. It is a calcium-permeable non-selective cation channel that regulates intracellular calcium concentration and thereby calcium signaling. PKD2L1 has been reported to take part in hedgehog signaling in renal primary cilia and sour tasting coupling with PKD1L3. In addition to the previous reports, PKD2L1 is recently found to play a crucial role in localization with β2-adrenergic receptor (β2AR) on the neuronal primary cilia. The disruption of PKD2L1 leads to the loss of β2AR on the primary cilia and reduction in intracellular concentration of cyclic adenosine monophosphate (cAMP). Since the role of cAMP and PKA is frequently mentioned in the studies of PKD diseases, we investigated on the mechanism of cAMP regulation in relation to the function of PKD2L1 channel. In this study, we observed the activity of PKD2L1 channel increased by the downstream cascades of β2AR and found the clustered phosphorylation sites, Ser-682, Ser-685, and Ser-686 that are significant in the channel regulation by phosphorylation.
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Affiliation(s)
- Eunice Yon June Park
- Department of Physiology, Seoul National University, College of Medicine, Biomedical Science Building 117, 103 Daehakro, Jongro-gu, Seoul, 110-799, South Korea
| | - Misun Kwak
- Department of Physiology, Seoul National University, College of Medicine, Biomedical Science Building 117, 103 Daehakro, Jongro-gu, Seoul, 110-799, South Korea
| | - Kotdaji Ha
- Department of Physiology, University of California, San Francisco, CA, 94158-2517, USA
| | - Insuk So
- Department of Physiology, Seoul National University, College of Medicine, Biomedical Science Building 117, 103 Daehakro, Jongro-gu, Seoul, 110-799, South Korea.
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11
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Lee J, Kim MS, Kim MA, Jang YK. Calmidazolium chloride inhibits growth of murine embryonal carcinoma cells, a model of cancer stem-like cells. Toxicol In Vitro 2016; 35:86-92. [PMID: 27247146 DOI: 10.1016/j.tiv.2016.05.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 04/07/2016] [Accepted: 05/27/2016] [Indexed: 01/01/2023]
Abstract
Calmidazolium chloride (CMZ) is widely used as a calmodulin (CaM) antagonist, but is also known to induce apoptosis in certain cancer cell lines. However, in spite of the importance of cancer stem cells (CSCs) in cancer therapy, the effects of CMZ on CSCs are not yet well understood. We investigated the effects of CMZ on the F9 embryonal carcinoma cell (ECC) line as a surrogate model of CSCs. To avoid bias due to culture conditions, F9 ECCs and E14 embryonic stem cells (ESCs) were grown in the same culture medium. Results obtained using a cell-counting kit showed that CMZ significantly inhibited growth in F9 ECCs compared with growth in E14 ESCs. CMZ also induced apoptosis of F9 ECCs, but not of E14 ESCs, which was associated with caspase-3 activation and an increased fraction of the sub-G1 cell population. In addition, our data revealed that the expression of stemness-related genes including c-Myc was selectively down regulated in CMZ-treated F9 ECCs. Our results suggest that CMZ can inhibit the growth of ECCs by inducing apoptosis and down regulating stemness-related genes, without causing any harm to normal stem cells. These findings indicate a potential application of CMZ in the development of anti-CSC therapeutics.
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Affiliation(s)
- Jina Lee
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea; Initiative for Biological Function & Systems, Yonsei University, Seoul 120-749, Republic of Korea
| | - Min Seong Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea; Initiative for Biological Function & Systems, Yonsei University, Seoul 120-749, Republic of Korea
| | - Min Aeh Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea; Initiative for Biological Function & Systems, Yonsei University, Seoul 120-749, Republic of Korea
| | - Yeun Kyu Jang
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea; Initiative for Biological Function & Systems, Yonsei University, Seoul 120-749, Republic of Korea.
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12
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Datta D, Khatri P, Banerjee C, Singh A, Meena R, Saha DR, Raman R, Rajamani P, Mitra A, Mazumder S. Calcium and Superoxide-Mediated Pathways Converge to Induce Nitric Oxide-Dependent Apoptosis in Mycobacterium fortuitum-Infected Fish Macrophages. PLoS One 2016; 11:e0146554. [PMID: 26752289 PMCID: PMC4713470 DOI: 10.1371/journal.pone.0146554] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 12/19/2015] [Indexed: 12/31/2022] Open
Abstract
Mycobacterium fortuitum causes ‘mycobacteriosis’ in wide range of hosts although the mechanisms remain largely unknown. Here we demonstrate the role of calcium (Ca+2)-signalling cascade on M. fortuitum-induced apoptosis in headkidney macrophages (HKM) of Clarias sp. M. fortuitum could trigger intracellular-Ca+2 influx leading to the activation of calmodulin (CaM), protein kinase C alpha (PKCα) and Calmodulin kinase II gamma (CaMKIIg). Gene silencing and inhibitor studies established the role of CaM in M. fortuitum pathogenesis. We noted that CaMKIIg activation is regulated by CaM as well as PKCα-dependent superoxide anions. This is altogether first report of oxidised CaMKIIg in mycobacterial infections. Our studies with targeted-siRNA and pharmacological inhibitors implicate CaMKIIg to be pro-apoptotic and critical for the activation of extra-cellular signal regulated kinase 1/2 (ERK1/2). Inhibiting the ERK1/2 pathway attenuated nitric oxide synthase 2 (NOS2)-induced nitric oxide (NO) production. Conversely, inhibiting the NOS2-NO axis by specific-siRNA and inhibitors down-regulated ERK1/2 activation suggesting the crosstalk between ERK1/2 and NO is essential for pathogenesis induced by the bacterium. Silencing the NOS2-NO axis enhanced intracellular bacterial survival and attenuated caspase-8 mediated activation of caspase-3 in the infected HKM. Our findings unveil hitherto unknown mechanism of M. fortuitum pathogenesis. We propose that M. fortuitum triggers intracellular Ca+2 elevations resulting in CaM activation and PKCα-mediated superoxide generation. The cascade converges in common pathway mediated by CaMKIIg resulting in the activation of ERK1/2-NOS2 axis. The crosstalk between ERK1/2 and NO shifts the balance in favour of caspase dependent apoptosis of M. fortuitum-infected HKM.
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Affiliation(s)
- Debika Datta
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, India
| | - Preeti Khatri
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, India
| | - Chaitali Banerjee
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, India
| | - Ambika Singh
- Gut Biology Laboratory, Department of Zoology, University of Delhi, Delhi, India
| | - Ramavatar Meena
- School of Environmental Sciences, Jawaharlal Nehru University, Delhi, India
| | - Dhira Rani Saha
- Microscopy Laboratory, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Rajagopal Raman
- Gut Biology Laboratory, Department of Zoology, University of Delhi, Delhi, India
| | - Paulraj Rajamani
- School of Environmental Sciences, Jawaharlal Nehru University, Delhi, India
| | - Abhijit Mitra
- Genome Analysis Laboratory, Animal Division, Indian Veterinary Research Institute, Izatnagar, Bareilly, India
| | - Shibnath Mazumder
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, India
- * E-mail:
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13
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Szabo M, Dulka K, Gulya K. Calmodulin inhibition regulates morphological and functional changes related to the actin cytoskeleton in pure microglial cells. Brain Res Bull 2015; 120:41-57. [PMID: 26551061 DOI: 10.1016/j.brainresbull.2015.11.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/26/2015] [Accepted: 11/03/2015] [Indexed: 01/24/2023]
Abstract
The roles of calmodulin (CaM), a multifunctional intracellular calcium receptor protein, as concerns selected morphological and functional characteristics of pure microglial cells derived from mixed primary cultures from embryonal forebrains of rats, were investigated through use of the CaM antagonists calmidazolium (CALMID) and trifluoperazine (TFP). The intracellular localization of the CaM protein relative to phalloidin, a bicyclic heptapeptide that binds only to filamentous actin, and the ionized calcium-binding adaptor molecule 1 (Iba1), a microglia-specific actin-binding protein, was determined by immunocytochemistry, with quantitative analysis by immunoblotting. In unchallenged and untreated (control) microglia, high concentrations of CaM protein were found mainly perinuclearly in ameboid microglia, while the cell cortex had a smaller CaM content that diminished progressively deeper into the branches in the ramified microglia. The amounts and intracellular distributions of both Iba1 and CaM proteins were altered after lipopolysaccharide (LPS) challenge in activated microglia. CALMID and TFP exerted different, sometimes opposing, effects on many morphological, cytoskeletal and functional characteristics of the microglial cells. They affected the CaM and Iba1 protein expressions and their intracellular localizations differently, inhibited cell proliferation, viability and fluid-phase phagocytosis to different degrees both in unchallenged and in LPS-treated (immunologically challenged) cells, and differentially affected the reorganization of the actin cytoskeleton in the microglial cell cortex, influencing lamellipodia, filopodia and podosome formation. In summary, these CaM antagonists altered different aspects of filamentous actin-based cell morphology and related functions with variable efficacy, which could be important in deciphering the roles of CaM in regulating microglial functions in health and disease.
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Affiliation(s)
- Melinda Szabo
- Department of Cell Biology and Molecular Medicine, University of Szeged, Szeged, Hungary
| | - Karolina Dulka
- Department of Cell Biology and Molecular Medicine, University of Szeged, Szeged, Hungary
| | - Karoly Gulya
- Department of Cell Biology and Molecular Medicine, University of Szeged, Szeged, Hungary.
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14
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Rodríguez-Moreno A, Sihra TS. Presynaptic kainate receptor-mediated facilitation of glutamate release involves Ca2+-calmodulin and PKA in cerebrocortical synaptosomes. FEBS Lett 2013; 587:788-92. [PMID: 23416300 DOI: 10.1016/j.febslet.2013.01.071] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 01/14/2013] [Accepted: 01/31/2013] [Indexed: 10/27/2022]
Abstract
We have explored the mechanisms involved in the facilitation of glutamate release mediated by the activation of kainate receptors (KARs) in the cortex using isolated nerve terminals (synaptosomes). Kainate (KA) produced an increase on glutamate release at 100 μM. The effect of KA was antagonized by NBQX (with AMPA receptors blocked by GYKI53655). This facilitation was suppressed by the inhibition of PKA activation by Rp-Br-cAMP and H-89. Moreover, the facilitation of glutamate release mediated by KAR requires the mobilization of intrasynaptosomal Ca(2+) stores and the formation of a Ca(2+)-calmodulin complex. We conclude that KARs present on presynaptic terminals in the neocortex mediate the facilitation of glutamate release through a mechanism involving an increase in cytosolic Ca(2+) to activate a Ca(2+)-calmodulin-AC/cAMP/PKA signaling cascade.
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Affiliation(s)
- Antonio Rodríguez-Moreno
- Laboratory of Cellular Neuroscience and Plasticity, Department of Physiology, Anatomy and Cellular Biology, University Pablo de Olavide, Seville, Spain.
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15
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Mine N, Yamamoto S, Saito N, Yamazaki S, Suda C, Ishigaki M, Kufe DW, Von Hoff DD, Kawabe T. CBP501-calmodulin binding contributes to sensitizing tumor cells to cisplatin and bleomycin. Mol Cancer Ther 2011; 10:1929-38. [PMID: 21831962 DOI: 10.1158/1535-7163.mct-10-1139] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
CBP501 is an anticancer drug currently in randomized phase II clinical trials for patients with non-small cell lung cancer and malignant pleural mesothelioma. CBP501 was originally described as a unique G(2) checkpoint-directed agent that binds to 14-3-3, inhibiting the actions of Chk1, Chk2, mitogen-activated protein kinase-activated protein kinase 2, and C-Tak1. However, unlike a G(2) checkpoint inhibitor, CBP501 clearly enhances the accumulation of tumor cells at G(2)-M phase that is induced by cisplatin or bleomycin at low doses and short exposure. By contrast, CBP501 does not similarly affect the accumulation of tumor cells at G(2)-M that is induced by radiation, doxorubicin, or 5-fluorouracil treatment. Our recent findings point to an additional mechanism of action for CBP501. The enhanced accumulation of tumor cells at G(2)-M upon combined treatment with cisplatin and CBP501 results from an increase in intracellular platinum concentrations, which leads to increased binding of platinum to DNA. The observed CBP501-enhanced platinum accumulation is negated in the presence of excess Ca(2+). Some calmodulin inhibitors behave similarly to, although less potently than, CBP501. Furthermore, analysis by surface plasmon resonance reveals a direct, high-affinity molecular interaction between CBP501 and CaM (K(d) = 4.62 × 10(-8) mol/L) that is reversed by Ca(2+), whereas the K(d) for the complex between CBP501 and 14-3-3 is approximately 10-fold weaker and is Ca(2+) independent. We conclude that CaM inhibition contributes to CBP501's activity in sensitizing cancer cells to cisplatin or bleomycin. This article presents an additional mechanism of action which might explain the clinical activity of the CBP501-cisplatin combination.
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Affiliation(s)
- Naoki Mine
- CanBas Co., Ltd., 2-2-1 Otemachi, Numazu City 410-0801, Japan
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16
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Calmodulin-dependent nuclear import of HMG-box family nuclear factors: importance of the role of SRY in sex reversal. Biochem J 2010; 430:39-48. [PMID: 20528776 PMCID: PMC2911679 DOI: 10.1042/bj20091758] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The HMG (high-mobility group)-box-containing chromatin-remodelling factor SRY (sex-determining region on the Y chromosome) plays a key role in sex determination. Its role in the nucleus is critically dependent on two NLSs (nuclear localization signals) that flank its HMG domain: the C-terminally located 'beta-NLS' that mediates nuclear transport through Impbeta1 (importin beta1) and the N-terminally located 'CaM-NLS' which is known to recognize the calcium-binding protein CaM (calmodulin). In the present study, we examined a number of missense mutations in the SRY CaM-NLS from human XY sex-reversed females for the first time, showing that they result in significantly reduced nuclear localization of GFP (green fluorescent protein)-SRY fusion proteins in transfected cells compared with wild-type. The CaM antagonist CDZ (calmidazolium chloride) was found to significantly reduce wild-type SRY nuclear accumulation, indicating dependence of SRY nuclear import on CaM. Intriguingly, the CaM-NLS mutants were all resistant to CDZ's effects, implying a loss of interaction with CaM, which was confirmed by direct binding experiments. CaM-binding/resultant nuclear accumulation was the only property of SRY found to be impaired by two of the CaM-NLS mutations, implying that inhibition of CaM-dependent nuclear import is the basis of sex reversal in these cases. Importantly, the CaM-NLS is conserved in other HMG-box-domain-containing proteins such as SOX-2, -9, -10 and HMGN1, all of which were found for the first time to rely on CaM for optimal nuclear localization. CaM-dependent nuclear translocation is thus a common mechanism for this family of important transcription factors.
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17
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Kumar S, Kain V, Sitasawad SL. Cardiotoxicity of calmidazolium chloride is attributed to calcium aggravation, oxidative and nitrosative stress, and apoptosis. Free Radic Biol Med 2009; 47:699-709. [PMID: 19497364 DOI: 10.1016/j.freeradbiomed.2009.05.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 05/05/2009] [Accepted: 05/20/2009] [Indexed: 10/20/2022]
Abstract
The intracellular calcium concentration ([Ca](i)) regulates cell viability and contractility in myocardial cells. Elevation of the [Ca](i) level occurs by entry of calcium ions (Ca(2+)) through voltage-dependent Ca(2+) channels in the plasma membrane and release of Ca(2+) from the sarcoplasmic reticulum. Calmidazolium chloride (CMZ), a subgroup II calmodulin antagonist, blocks L-type calcium channels as well as voltage-dependent Na(+) and K(+) channel currents. This study elaborates on the events that contribute to the cytotoxic effects of CMZ on the heart. We hypothesized that apoptotic cell death occurs in the cardiac cells through calcium accumulation, production of reactive oxygen species, and the cytochrome c-mediated PARP activation pathway. CMZ significantly increased the production of superoxide (O(2)(*-)) and nitric oxide (NO) as detected by FACS and confocal microscopy. CMZ induced mitochondrial damage by increasing the levels of intracellular calcium, lowering the mitochondrial membrane potential, and thereby inducing cytochrome c release. Apoptotic cell death was observed in H9c2 cells exposed to 25 microM CMZ for 24 h. This is the first report that elaborates on the mechanism of CMZ-induced cardiotoxicity. CMZ causes apoptosis by decreasing mitochondrial activity and contractility indices and increasing oxidative and nitrosative stress, ultimately leading to cell death via an intrinsic apoptotic pathway.
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Affiliation(s)
- Sandeep Kumar
- National Centre for Cell Science, NCCS Complex, Pune University Campus, Ganeshkhind, Pune 411007, Maharashtra, India
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