51
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Raina A, Leite K, Guerin S, Mahajani SU, Chakrabarti KS, Voll D, Becker S, Griesinger C, Bähr M, Kügler S. Dopamine promotes the neurodegenerative potential of β-synuclein. J Neurochem 2020; 156:674-691. [PMID: 32730640 DOI: 10.1111/jnc.15134] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/09/2020] [Accepted: 07/21/2020] [Indexed: 01/21/2023]
Abstract
A contribution of α-Synuclein (α-Syn) to etiology of Parkinson´s disease (PD) and Dementia with Lewy bodies (DLB) is currently undisputed, while the impact of the closely related β-Synuclein (β-Syn) on these disorders remains enigmatic. β-Syn has long been considered to be an attenuator of the neurotoxic effects of α-Syn, but in a rodent model of PD β-Syn induced robust neurodegeneration in dopaminergic neurons of the substantia nigra. Given that dopaminergic nigral neurons are selectively vulnerable to neurodegeneration in PD, we now investigated if dopamine can promote the neurodegenerative potential of β-Syn. We show that in cultured rodent and human neurons a dopaminergic neurotransmitter phenotype substantially enhanced β-Syn-induced neurodegeneration, irrespective if dopamine is synthesized within neurons or up-taken from extracellular space. Nuclear magnetic resonance interaction and thioflavin-T incorporation studies demonstrated that dopamine and its oxidized metabolites 3,4-dihydroxyphenylacetaldehyde (DOPAL) and dopaminochrome (DCH) directly interact with β-Syn, thereby enabling structural and functional modifications. Interaction of DCH with β-Syn inhibits its aggregation, which might result in increased levels of neurotoxic oligomeric β-Syn. Since protection of outer mitochondrial membrane integrity prevented the additive neurodegenerative effect of dopamine and β-Syn, such oligomers might act at a mitochondrial level similar to what is suggested for α-Syn. In conclusion, our results suggest that β-Syn can play a significant pathophysiological role in etiology of PD through its interaction with dopamine metabolites and thus should be re-considered as a disease-relevant factor, at least for those symptoms of PD that depend on degeneration of nigral dopaminergic neurons.
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Affiliation(s)
- Anupam Raina
- Department of Neurology, University Medicine Göttingen, Göttingen, Germany
| | - Kristian Leite
- Department of Neurology, University Medicine Göttingen, Göttingen, Germany
| | - Sofia Guerin
- Department of Neurology, University Medicine Göttingen, Göttingen, Germany
| | | | | | - Diana Voll
- Department of Neurology, University Medicine Göttingen, Göttingen, Germany
| | - Stefan Becker
- Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
| | | | - Mathias Bähr
- Department of Neurology, University Medicine Göttingen, Göttingen, Germany
| | - Sebastian Kügler
- Department of Neurology, University Medicine Göttingen, Göttingen, Germany.,Center Nanoscale Microscopy and Physiology of the Brain (CNMPB), Göttingen, Germany
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52
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Molecular mechanism of mitochondrial phosphatidate transfer by Ups1. Commun Biol 2020; 3:468. [PMID: 32843686 PMCID: PMC7447767 DOI: 10.1038/s42003-020-01121-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 07/03/2020] [Indexed: 01/07/2023] Open
Abstract
Cardiolipin, an essential mitochondrial physiological regulator, is synthesized from phosphatidic acid (PA) in the inner mitochondrial membrane (IMM). PA is synthesized in the endoplasmic reticulum and transferred to the IMM via the outer mitochondrial membrane (OMM) under mediation by the Ups1/Mdm35 protein family. Despite the availability of numerous crystal structures, the detailed mechanism underlying PA transfer between mitochondrial membranes remains unclear. Here, a model of Ups1/Mdm35-membrane interaction is established using combined crystallographic data, all-atom molecular dynamics simulations, extensive structural comparisons, and biophysical assays. The α2-loop, L2-loop, and α3 helix of Ups1 mediate membrane interactions. Moreover, non-complexed Ups1 on membranes is found to be a key transition state for PA transfer. The membrane-bound non-complexed Ups1/ membrane-bound Ups1 ratio, which can be regulated by environmental pH, is inversely correlated with the PA transfer activity of Ups1/Mdm35. These results demonstrate a new model of the fine conformational changes of Ups1/Mdm35 during PA transfer.
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53
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Sedivy P, Dezortova M, Drobny M, Dubsky M, Dusilova T, Kovar J, Hajek M. Origin of the 31 P MR signal at 5.3 ppm in patients with critical limb ischemia. NMR IN BIOMEDICINE 2020; 33:e4295. [PMID: 32180296 DOI: 10.1002/nbm.4295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 02/28/2020] [Accepted: 02/29/2020] [Indexed: 06/10/2023]
Abstract
An unknown intense signal (Pun ) with a mean chemical shift of 5.3 ppm was observed in 31 P MR spectra from the calf muscles of patients with the diabetic foot syndrome. The aim of the study was to identify the origin of this signal and its potential as a biomarker of muscle injury. Calf muscles of 68 diabetic patients (66.3 ± 8.6 years; body mass index = 28.2 ± 4.3 kg/m2 ) and 12 age-matched healthy controls were examined by (dynamic) 31 P MRS (3 T system, 31 P/1 H coil). Phantoms (glucose-1-phosphate, Pi and PCr) were measured at pH values of 7.05 and 7.51. At rest, Pun signals with intensities higher than 50% of the Pi intensity were observed in 10 of the 68 examined diabetic subjects. We tested two hypothetical origins of the Pun signal: (1) phosphorus from phosphoesters and (2) phosphorus from extra- and intracellular alkaline phosphate pools. 2,3-diphosphoglycerate and glucose-1-phosphate are the only phosphoesters with signals in the chemical shift region close to 5.3 ppm. Both compounds can be excluded: 2,3-diphosphoglycerate due to the missing second signal component at 6.31 ppm; glucose-1-phosphate because its chemical shifts are about 0.2 ppm downfield from the Pi signal (4.9 ppm). If the Pun signal is from phosphate, it represents a pH value of 7.54 ± 0.05. Therefore, it could correspond to signals of Pi in mitochondria. However, patients with critical limb ischemia have rather few mitochondria and so the Pun signal probably originates from interstitia. Our data suggest that the increased Pun signal observed in patients with the diabetic foot syndrome is a biomarker of severe muscular damage.
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Affiliation(s)
- Petr Sedivy
- MR Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Monika Dezortova
- MR Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Miloslav Drobny
- MR Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Michal Dubsky
- Department of Diabetology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Tereza Dusilova
- MR Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Jan Kovar
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Milan Hajek
- MR Unit, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
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54
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Ripoll C, Roldan M, Contreras-Montoya R, Diaz-Mochon JJ, Martin M, Ruedas-Rama MJ, Orte A. Mitochondrial pH Nanosensors for Metabolic Profiling of Breast Cancer Cell Lines. Int J Mol Sci 2020; 21:E3731. [PMID: 32466332 PMCID: PMC7279253 DOI: 10.3390/ijms21103731] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 12/12/2022] Open
Abstract
The main role of mitochondria, as pivotal organelles for cellular metabolism, is the production of energy (ATP) through an oxidative phosphorylation system. During this process, the electron transport chain creates a proton gradient that drives the synthesis of ATP. One of the main features of tumoral cells is their altered metabolism, providing alternative routes to enhance proliferation and survival. Hence, it is of utmost importance to understand the relationship between mitochondrial pH, tumoral metabolism, and cancer. In this manuscript, we develop a highly specific nanosensor to accurately measure the intramitochondrial pH using fluorescence lifetime imaging microscopy (FLIM). Importantly, we have applied this nanosensor to establish differences that may be hallmarks of different metabolic pathways in breast cancer cell models, leading to the characterization of different metabophenotypes.
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Affiliation(s)
- Consuelo Ripoll
- Departamento de Fisicoquimica, Facultad de Farmacia, Unidad de Excelencia en Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, Campus Cartuja, 18071 Granada, Spain; (C.R.); (M.J.R.-R.)
| | - Mar Roldan
- GENYO, Pfizer-Universidad de Granada-Junta de Andalucia Centre for Genomics and Oncological Research, Avda Ilustracion 114, PTS, 18016 Granada, Spain; (M.R.); (J.J.D.-M.); (M.M)
| | - Rafael Contreras-Montoya
- Departamento de Quimica Organica, Facultad de Ciencias, Unidad de Excelencia en Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, Campus Fuentenueva, 18071 Granada, Spain;
| | - Juan J. Diaz-Mochon
- GENYO, Pfizer-Universidad de Granada-Junta de Andalucia Centre for Genomics and Oncological Research, Avda Ilustracion 114, PTS, 18016 Granada, Spain; (M.R.); (J.J.D.-M.); (M.M)
- Departamento de Quimica Farmaceutica y Organica, Facultad de Farmacia, Unidad de Excelencia en Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, Campus Cartuja, 18071 Granada, Spain
| | - Miguel Martin
- GENYO, Pfizer-Universidad de Granada-Junta de Andalucia Centre for Genomics and Oncological Research, Avda Ilustracion 114, PTS, 18016 Granada, Spain; (M.R.); (J.J.D.-M.); (M.M)
- Departamento de Bioquimica y Biologia Celular I, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva, 18071 Granada, Spain
| | - Maria J. Ruedas-Rama
- Departamento de Fisicoquimica, Facultad de Farmacia, Unidad de Excelencia en Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, Campus Cartuja, 18071 Granada, Spain; (C.R.); (M.J.R.-R.)
| | - Angel Orte
- Departamento de Fisicoquimica, Facultad de Farmacia, Unidad de Excelencia en Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, Campus Cartuja, 18071 Granada, Spain; (C.R.); (M.J.R.-R.)
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55
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Noble M, Lin QT, Sirko C, Houpt JA, Novello MJ, Stathopulos PB. Structural Mechanisms of Store-Operated and Mitochondrial Calcium Regulation: Initiation Points for Drug Discovery. Int J Mol Sci 2020; 21:E3642. [PMID: 32455637 PMCID: PMC7279490 DOI: 10.3390/ijms21103642] [Citation(s) in RCA: 2] [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: 04/13/2020] [Revised: 05/11/2020] [Accepted: 05/17/2020] [Indexed: 12/18/2022] Open
Abstract
Calcium (Ca2+) is a universal signaling ion that is essential for the life and death processes of all eukaryotes. In humans, numerous cell stimulation pathways lead to the mobilization of sarco/endoplasmic reticulum (S/ER) stored Ca2+, resulting in the propagation of Ca2+ signals through the activation of processes, such as store-operated Ca2+ entry (SOCE). SOCE provides a sustained Ca2+ entry into the cytosol; moreover, the uptake of SOCE-mediated Ca2+ by mitochondria can shape cytosolic Ca2+ signals, function as a feedback signal for the SOCE molecular machinery, and drive numerous mitochondrial processes, including adenosine triphosphate (ATP) production and distinct cell death pathways. In recent years, tremendous progress has been made in identifying the proteins mediating these signaling pathways and elucidating molecular structures, invaluable for understanding the underlying mechanisms of function. Nevertheless, there remains a disconnect between using this accumulating protein structural knowledge and the design of new research tools and therapies. In this review, we provide an overview of the Ca2+ signaling pathways that are involved in mediating S/ER stored Ca2+ release, SOCE, and mitochondrial Ca2+ uptake, as well as pinpoint multiple levels of crosstalk between these pathways. Further, we highlight the significant protein structures elucidated in recent years controlling these Ca2+ signaling pathways. Finally, we describe a simple strategy that aimed at applying the protein structural data to initiating drug design.
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Affiliation(s)
- Megan Noble
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Qi-Tong Lin
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Christian Sirko
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Jacob A. Houpt
- Department of Medicine, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada;
| | - Matthew J. Novello
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Peter B. Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
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56
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Abstract
Mitochondria are essential organelles in eukaryotes. Most mitochondrial proteins are encoded by the nuclear genome and translated in the cytosol. Nuclear-encoded mitochondrial proteins need to be imported, processed, folded, and assembled into their functional states. To maintain protein homeostasis (proteostasis), mitochondria are equipped with a distinct set of quality control machineries. Deficiencies in such systems lead to mitochondrial dysfunction, which is a hallmark of aging and many human diseases, such as neurodegenerative diseases, cardiovascular diseases, and cancer. In this review, we discuss the unique challenges and solutions of proteostasis in mitochondria. The import machinery coordinates with mitochondrial proteases and chaperones to maintain the mitochondrial proteome. Moreover, mitochondrial proteostasis depends on cytosolic protein quality control mechanisms during crises. In turn, mitochondria facilitate cytosolic proteostasis. Increasing evidence suggests that enhancing mitochondrial proteostasis may hold therapeutic potential to protect against protein aggregation-associated cellular defects.
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Affiliation(s)
- Linhao Ruan
- Center for Cell Dynamics, Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; , , , , ,
- Biochemistry, Cellular and Molecular Biology (BCMB) Graduate Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Yuhao Wang
- Center for Cell Dynamics, Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; , , , , ,
- Biochemistry, Cellular and Molecular Biology (BCMB) Graduate Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Xi Zhang
- Center for Cell Dynamics, Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; , , , , ,
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Alexis Tomaszewski
- Center for Cell Dynamics, Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; , , , , ,
- Biochemistry, Cellular and Molecular Biology (BCMB) Graduate Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Joshua T McNamara
- Center for Cell Dynamics, Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; , , , , ,
- Biochemistry, Cellular and Molecular Biology (BCMB) Graduate Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Rong Li
- Center for Cell Dynamics, Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; , , , , ,
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
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57
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Ghazi S, Bourgeois S, Gomariz A, Bugarski M, Haenni D, Martins JR, Nombela-Arrieta C, Unwin RJ, Wagner CA, Hall AM, Craigie E. Multiparametric imaging reveals that mitochondria-rich intercalated cells in the kidney collecting duct have a very high glycolytic capacity. FASEB J 2020; 34:8510-8525. [PMID: 32367531 DOI: 10.1096/fj.202000273r] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/30/2020] [Accepted: 04/16/2020] [Indexed: 02/06/2023]
Abstract
Alpha intercalated cells (αICs) in the kidney collecting duct (CD) belong to a family of mitochondria rich cells (MRCs) and have a crucial role in acidifying the urine via apical V-ATPase pumps. The nature of metabolism in αICs and its relationship to transport was not well-understood. Here, using multiphoton live cell imaging in mouse kidney tissue, FIB-SEM, and other complementary techniques, we provide new insights into mitochondrial structure and function in αICs. We show that αIC mitochondria have a rounded structure and are not located in close proximity to V-ATPase containing vesicles. They display a bright NAD(P)H fluorescence signal and low uptake of voltage-dependent dyes, but are energized by a pH gradient. However, expression of complex V (ATP synthase) is relatively low in αICs, even when stimulated by metabolic acidosis. In contrast, anaerobic glycolytic capacity is surprisingly high, and sufficient to maintain intracellular calcium homeostasis in the presence of complete aerobic inhibition. Moreover, glycolysis is essential for V-ATPase-mediated proton pumping. Key findings were replicated in narrow/clear cells in the epididymis, also part of the MRC family. In summary, using a range of cutting-edge techniques to investigate αIC metabolism in situ, we have discovered that these mitochondria dense cells have a high glycolytic capacity.
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Affiliation(s)
- Susan Ghazi
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Soline Bourgeois
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Alvaro Gomariz
- Department of Medical Oncology and Hematology, University of Zurich, Zurich, Switzerland.,Computer Vision Laboratory, ETH Zurich, Zurich, Switzerland
| | - Milica Bugarski
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Dominik Haenni
- Institute of Anatomy, University of Zurich, Zurich, Switzerland.,Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Joana R Martins
- Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - César Nombela-Arrieta
- Department of Medical Oncology and Hematology, University of Zurich, Zurich, Switzerland
| | - Robert J Unwin
- Department of Renal Medicine, University College London, UK.,AstraZeneca Biopharmaceuticals R&D, Gothenburg, Sweden
| | - Carsten A Wagner
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Andrew M Hall
- Institute of Anatomy, University of Zurich, Zurich, Switzerland.,Department of Nephrology, University Hospital Zurich, Switzerland
| | - Eilidh Craigie
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
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58
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Precipitation of Inorganic Salts in Mitochondrial Matrix. MEMBRANES 2020; 10:membranes10050081. [PMID: 32349446 PMCID: PMC7281443 DOI: 10.3390/membranes10050081] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/17/2020] [Accepted: 04/19/2020] [Indexed: 11/17/2022]
Abstract
In the mitochondrial matrix, there are insoluble, osmotically inactive complexes that maintain a constant pH and calcium concentration. In the present paper, we examine the properties of insoluble calcium and magnesium salts, such as phosphates, carbonates and polyphosphates, which might play this role. We find that non-stoichiometric, magnesium-rich carbonated apatite, with very low crystallinity, precipitates in the matrix under physiological conditions. Precipitated salt acts as pH buffer, and, hence, can contribute in maintaining ATP production in ischemic conditions, which delays irreversible damage to heart and brain cells after stroke.
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59
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Cho H, Cho YY, Shim MS, Lee JY, Lee HS, Kang HC. Mitochondria-targeted drug delivery in cancers. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165808. [PMID: 32333953 DOI: 10.1016/j.bbadis.2020.165808] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 04/14/2020] [Accepted: 04/16/2020] [Indexed: 12/13/2022]
Abstract
Mitochondria are considered one of the most important subcellular organelles for targeting and delivering drugs because mitochondria are the main location for various cellular functions and energy (i.e., ATP) production, and mitochondrial dysfunctions and malfunctions cause diverse diseases such as neurodegenerative disorders, cardiovascular disorders, metabolic disorders, and cancers. In particular, unique mitochondrial characteristics (e.g., negatively polarized membrane potential, alkaline pH, high reactive oxygen species level, high glutathione level, high temperature, and paradoxical mitochondrial dynamics) in pathological cancers have been used as targets, signals, triggers, or driving forces for specific sensing/diagnosing/imaging of characteristic changes in mitochondria, targeted drug delivery on mitochondria, targeted drug delivery/accumulation into mitochondria, or stimuli-triggered drug release in mitochondria. In this review, we describe the distinctive structures, functions, and physiological properties of cancer mitochondria and discuss recent technologies of mitochondria-specific "key characteristic" sensing systems, mitochondria-targeted "drug delivery" systems, and mitochondrial stimuli-specific "drug release" systems as well as their strengths and weaknesses.
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Affiliation(s)
- Hana Cho
- Department of Pharmacy and BK21PLUS Team for Creative Leader Program for Pharmacomics-based Future Pharmacy, College of Pharmacy, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Yong-Yeon Cho
- Department of Pharmacy and BK21PLUS Team for Creative Leader Program for Pharmacomics-based Future Pharmacy, College of Pharmacy, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Min Suk Shim
- Division of Bioengineering, Incheon National University, Incheon 22012, Republic of Korea
| | - Joo Young Lee
- Department of Pharmacy and BK21PLUS Team for Creative Leader Program for Pharmacomics-based Future Pharmacy, College of Pharmacy, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Hye Suk Lee
- Department of Pharmacy and BK21PLUS Team for Creative Leader Program for Pharmacomics-based Future Pharmacy, College of Pharmacy, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Han Chang Kang
- Department of Pharmacy and BK21PLUS Team for Creative Leader Program for Pharmacomics-based Future Pharmacy, College of Pharmacy, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi-do 14662, Republic of Korea.
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60
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Moreno-Sánchez R, Marín-Hernández Á, Gallardo-Pérez JC, Pacheco-Velázquez SC, Robledo-Cadena DX, Padilla-Flores JA, Saavedra E, Rodríguez-Enríquez S. Physiological Role of Glutamate Dehydrogenase in Cancer Cells. Front Oncol 2020; 10:429. [PMID: 32328457 PMCID: PMC7160333 DOI: 10.3389/fonc.2020.00429] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 03/10/2020] [Indexed: 12/29/2022] Open
Abstract
NH 4 + increased growth rates and final densities of several human metastatic cancer cells. To assess whether glutamate dehydrogenase (GDH) in cancer cells may catalyze the reverse reaction of NH 4 + fixation, its covalent regulation and kinetic parameters were determined under near-physiological conditions. Increased total protein and phosphorylation were attained in NH 4 + -supplemented metastatic cells, but total cell GDH activity was unchanged. Higher V max values for the GDH reverse reaction vs. forward reaction in both isolated hepatoma (HepM) and liver mitochondria [rat liver mitochondria (RLM)] favored an NH 4 + -fixing role. GDH sigmoidal kinetics with NH 4 + , ADP, and leucine fitted to Hill equation showed n H values of 2 to 3. However, the K 0.5 values for NH 4 + were over 20 mM, questioning the physiological relevance of the GDH reverse reaction, because intracellular NH 4 + in tumors is 1 to 5 mM. In contrast, data fitting to the Monod-Wyman-Changeux (MWC) model revealed lower K m values for NH 4 + , of 6 to 12 mM. In silico analysis made with MWC equation, and using physiological concentrations of substrates and modulators, predicted GDH N-fixing activity in cancer cells. Therefore, together with its thermodynamic feasibility, GDH may reach rates for its reverse, NH 4 + -fixing reaction that are compatible with an anabolic role for supporting growth of cancer cells.
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Affiliation(s)
- Rafael Moreno-Sánchez
- Departamento de Bioquímica, Instituto Nacional de Cardiología, Ciudad de México, Mexico
| | | | - Juan C Gallardo-Pérez
- Departamento de Bioquímica, Instituto Nacional de Cardiología, Ciudad de México, Mexico
| | | | | | | | - Emma Saavedra
- Departamento de Bioquímica, Instituto Nacional de Cardiología, Ciudad de México, Mexico
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61
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Rieger B, Thierbach S, Ommer M, Dienhart FSV, Fetzner S, Busch KB. Pseudomonas Quinolone Signal molecule PQS behaves like a B Class inhibitor at the I Q site of mitochondrial complex I. FASEB Bioadv 2020; 2:188-202. [PMID: 32161908 PMCID: PMC7059627 DOI: 10.1096/fba.2019-00084] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 10/17/2019] [Accepted: 01/14/2020] [Indexed: 12/24/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram‐negative bacterium of the proteobacteria class, and one of the most common causes of nosocomial infections. For example, it causes chronic pneumonia in cystic fibrosis patients. Patient sputum contains 2‐heptyl‐4‐hydroxyquinoline N‐oxide [HQNO] and Pseudomonas quorum sensing molecules such as the Pseudomonas quinolone signal [PQS]. It is known that HQNO inhibits the enzyme activity of mitochondrial and bacterial complex III at the Qi (quinone reduction) site, but the target of PQS is not known. In this work we have shown that PQS has a negative effect on mitochondrial respiration in HeLa and A549 cells. It specifically inhibits the complex I of the respiratory chain. In vitro analyses showed a partially competitive inhibition with respect to ubiquinone at the IQ site. In competing studies with Rotenone, PQS suppressed the ROS‐promoting effect of Rotenone, which is typical for a B‐type inhibitor. Prolonged incubation with PQS also had an effect on the activity of complex III.
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Affiliation(s)
- Bettina Rieger
- Institute of Molecular Cell Biology Faculty of Biology University of Muenster Muenster Germany
| | - Sven Thierbach
- Institute for Molecular Microbiology and Biotechnology Faculty of Biology University of Muenster Muenster Germany
| | - Miriam Ommer
- Institute of Molecular Cell Biology Faculty of Biology University of Muenster Muenster Germany
| | - Finja S V Dienhart
- Institute of Molecular Cell Biology Faculty of Biology University of Muenster Muenster Germany
| | - Susanne Fetzner
- Institute for Molecular Microbiology and Biotechnology Faculty of Biology University of Muenster Muenster Germany
| | - Karin B Busch
- Institute of Molecular Cell Biology Faculty of Biology University of Muenster Muenster Germany
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62
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Strom A, Tong CL, Wagner CR. Histidine triad nucleotide-binding proteins HINT1 and HINT2 share similar substrate specificities and little affinity for the signaling dinucleotide Ap4A. FEBS Lett 2020; 594:1497-1505. [PMID: 31990367 DOI: 10.1002/1873-3468.13745] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 12/10/2019] [Accepted: 12/18/2019] [Indexed: 11/07/2022]
Abstract
Human histidine triad nucleotide-binding protein 2 (hHINT2) is an important player in human mitochondrial bioenergetics, but little is known about its catalytic capabilities or its nucleotide phosphoramidate prodrug (proTide)-activating activity akin to the cytosolic isozyme hHINT1. Here, a similar substrate specificity profile (kcat /Km ) for model phosphoramidate substrates was found for hHINT2 but with higher kcat and Km values when compared with hHINT1. A broader pH range for maximum catalytic activity was determined for hHINT2 (pK1 = 6.76 ± 0.16, pK2 = 8.41 ± 0.07). In addition, the known hHINT1-microphthalmia-inducing transcription factor-regulating molecule Ap4 A was found to have no detectable binding to HINT1 nor HINT2 by isothermal titration calorimetry. These results demonstrate that despite differences in their sequence and localization, HINT1 and HINT2 have similar nucleotide substrate specificities, which should be considered in future proTide design and in studies of their natural function.
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Affiliation(s)
- Alexander Strom
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Cher Ling Tong
- Department of Biochemistry Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Carston R Wagner
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
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63
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Laporte A, Lortz S, Schaal C, Lenzen S, Elsner M. Hydrogen peroxide permeability of cellular membranes in insulin-producing cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183096. [DOI: 10.1016/j.bbamem.2019.183096] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 09/15/2019] [Accepted: 10/02/2019] [Indexed: 01/30/2023]
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64
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Matamoros-Volante A, Treviño CL. Capacitation-associated alkalization in human sperm is differentially controlled at the subcellular level. J Cell Sci 2020; 133:jcs238816. [PMID: 31932506 DOI: 10.1242/jcs.238816] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/20/2019] [Indexed: 12/28/2022] Open
Abstract
Capacitation in mammalian sperm involves the accurate balance of intracellular pH (pHi), but the mechanisms controlling this process are not fully understood, particularly regarding the spatiotemporal regulation of the proteins involved in pHi modulation. Here, we employed an image-based flow cytometry technique combined with pharmacological approaches to study pHi dynamics at the subcellular level during capacitation. We found that, upon capacitation induction, sperm cells undergo intracellular alkalization in the head and principal piece regions. The observed localized pHi increases require the initial uptake of HCO3-, which is mediated by several proteins acting consistently with their subcellular localization. Hv1 proton channel (also known as HVCN1) and cAMP-activated protein kinase (protein kinase A, PKA) antagonists impair alkalization mainly in the principal piece. Na+/HCO3- cotransporter (NBC) and cystic fibrosis transmembrane regulator (CFTR) antagonists impair alkalization only mildly, predominantly in the head. Motility measurements indicate that inhibition of alkalization in the principal piece prevents the development of hyperactivated motility. Altogether, our findings shed light on the complex control mechanisms of pHi and underscore their importance during human sperm capacitation.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Arturo Matamoros-Volante
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, México
| | - Claudia L Treviño
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, México
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65
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Melzner F, Mark FC, Seibel BA, Tomanek L. Ocean Acidification and Coastal Marine Invertebrates: Tracking CO 2 Effects from Seawater to the Cell. ANNUAL REVIEW OF MARINE SCIENCE 2020; 12:499-523. [PMID: 31451083 DOI: 10.1146/annurev-marine-010419-010658] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In the last few decades, numerous studies have investigated the impacts of simulated ocean acidification on marine species and communities, particularly those inhabiting dynamic coastal systems. Despite these research efforts, there are many gaps in our understanding, particularly with respect to physiological mechanisms that lead to pathologies. In this review, we trace how carbonate system disturbances propagate from the coastal environment into marine invertebrates and highlight mechanistic links between these disturbances and organism function. We also point toward several processes related to basic invertebrate biology that are severely understudied and prevent an accurate understanding of how carbonate system dynamics influence organismic homeostasis and fitness-related traits. We recommend that significant research effort be directed to studying cellular phenotypes of invertebrates acclimated or adapted to elevated seawater pCO2 using biochemical and physiological methods.
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Affiliation(s)
- Frank Melzner
- Marine Ecology Research Division, GEOMAR Helmholtz Centre for Ocean Research Kiel, 24105 Kiel, Germany;
| | - Felix C Mark
- Department of Integrative Ecophysiology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany;
| | - Brad A Seibel
- College of Marine Science, University of South Florida, St. Petersburg, Florida 33701, USA;
| | - Lars Tomanek
- Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, California 93407, USA;
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66
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Hemmerová E, Špringer T, Krištofiková Z, Homola J. In vitro study of interaction of 17β-hydroxysteroid dehydrogenase type 10 and cyclophilin D and its potential implications for Alzheimer's disease. Sci Rep 2019; 9:16700. [PMID: 31723183 PMCID: PMC6853915 DOI: 10.1038/s41598-019-53157-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 10/29/2019] [Indexed: 01/08/2023] Open
Abstract
In early stages of Alzheimer's disease (AD), amyloid-β (Aβ) accumulates in neuronal mitochondria where it interacts with a number of biomolecules including 17beta-hydroxysteroide dehydrogenase 10 (17β-HSD10) and cyclophilin D (cypD). It has been hypothesized that 17β-HSD10 interacts with cypD preventing it from opening mitochondrial permeability transition pores and that its regulation during AD may be affected by the accumulation of Aβ. In this work, we demonstrate for the first time that 17β-HSD10 and cypD form a stable complex in vitro. Furthermore, we show that factors, such as pH, ionic environment and the presence of Aβ, affect the ability of 17β-HSD10 to bind cypD. We demonstrate that K+ and Mg2+ ions present at low levels may facilitate this binding. We also show that different fragments of Aβ (Aβ1-40 and Aβ1-42) affect the interaction between 17β-HSD10 and cypD differently and that Aβ1-42 (in contrast to Aβ1-40) is capable of simultaneously binding both 17β-HSD10 and cypD in a tri-complex.
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Affiliation(s)
- Erika Hemmerová
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 57, 182 51, Prague, Czech Republic
| | - Tomáš Špringer
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 57, 182 51, Prague, Czech Republic
| | - Zdenka Krištofiková
- National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic
| | - Jiří Homola
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 57, 182 51, Prague, Czech Republic.
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67
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Madreiter-Sokolowski CT, Ramadani-Muja J, Ziomek G, Burgstaller S, Bischof H, Koshenov Z, Gottschalk B, Malli R, Graier WF. Tracking intra- and inter-organelle signaling of mitochondria. FEBS J 2019; 286:4378-4401. [PMID: 31661602 PMCID: PMC6899612 DOI: 10.1111/febs.15103] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/19/2019] [Accepted: 10/22/2019] [Indexed: 12/15/2022]
Abstract
Mitochondria are as highly specialized organelles and masters of the cellular energy metabolism in a constant and dynamic interplay with their cellular environment, providing adenosine triphosphate, buffering Ca2+ and fundamentally contributing to various signaling pathways. Hence, such broad field of action within eukaryotic cells requires a high level of structural and functional adaptation. Therefore, mitochondria are constantly moving and undergoing fusion and fission processes, changing their shape and their interaction with other organelles. Moreover, mitochondrial activity gets fine-tuned by intra- and interorganelle H+ , K+ , Na+ , and Ca2+ signaling. In this review, we provide an up-to-date overview on mitochondrial strategies to adapt and respond to, as well as affect, their cellular environment. We also present cutting-edge technologies used to track and investigate subcellular signaling, essential to the understanding of various physiological and pathophysiological processes.
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Affiliation(s)
- Corina T Madreiter-Sokolowski
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria.,Department of Health Sciences and Technology, ETH Zurich, Schwerzenbach, Switzerland
| | - Jeta Ramadani-Muja
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Gabriela Ziomek
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Sandra Burgstaller
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Helmut Bischof
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Zhanat Koshenov
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Benjamin Gottschalk
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Roland Malli
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria.,BioTechMed, Graz, Austria
| | - Wolfgang F Graier
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria.,BioTechMed, Graz, Austria
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68
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Santo-Domingo J, Dayon L, Wiederkehr A. Protein Lysine Acetylation: Grease or Sand in the Gears of β-Cell Mitochondria? J Mol Biol 2019; 432:1446-1460. [PMID: 31628953 DOI: 10.1016/j.jmb.2019.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/16/2019] [Accepted: 09/18/2019] [Indexed: 02/06/2023]
Abstract
Mitochondria carry out many essential functions in metabolism. A central task is the oxidation of nutrients and the generation of ATP by oxidative phosphorylation. Mitochondrial metabolism needs to be tightly regulated for the cell to respond to changes in ATP demand and nutrient supply. Here, we review how protein lysine acetylation contributes to the regulation of mitochondrial metabolism in insulin target tissues and the insulin-secreting pancreatic β-cell. We summarize recent evidence showing that in pancreatic β-cells, lysine acetylation occurs on a large number of proteins involved in metabolism. Furthermore, we give a brief overview of the molecular mechanism that controls lysine acetylation dynamics. We propose that protein lysine acetylation is an important mechanism for the fine-tuning of mitochondrial activity in β-cells during normal physiology. In contrast, nutrient oversupply, oxidative stress, or inhibition of the mitochondrial deacetylase SIRT3 leads to protein lysine hyperacetylation, which impairs mitochondrial function. By perturbing mitochondrial activity in β-cells and insulin target tissues, protein lysine hyperacetylation may contribute to the development of type 2 diabetes.
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Affiliation(s)
- Jaime Santo-Domingo
- Mitochondrial Function, Nestlé Institute of Health Sciences, 1015 Lausanne, Switzerland
| | - Loïc Dayon
- Proteomics, Nestlé Institute of Health Sciences, 1015 Lausanne, Switzerland
| | - Andreas Wiederkehr
- Mitochondrial Function, Nestlé Institute of Health Sciences, 1015 Lausanne, Switzerland.
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69
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Live cell imaging of signaling and metabolic activities. Pharmacol Ther 2019; 202:98-119. [DOI: 10.1016/j.pharmthera.2019.06.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 05/31/2019] [Indexed: 12/15/2022]
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70
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Same same, but different: Uncovering unique features of the mitochondrial respiratory chain of apicomplexans. Mol Biochem Parasitol 2019; 232:111204. [DOI: 10.1016/j.molbiopara.2019.111204] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 07/19/2019] [Accepted: 08/01/2019] [Indexed: 01/08/2023]
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71
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Parui PP, Sarakar Y, Majumder R, Das S, Yang H, Yasuhara K, Hirota S. Determination of proton concentration at cardiolipin-containing membrane interfaces and its relation with the peroxidase activity of cytochrome c. Chem Sci 2019; 10:9140-9151. [PMID: 31827756 PMCID: PMC6889831 DOI: 10.1039/c9sc02993a] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/03/2019] [Indexed: 01/04/2023] Open
Abstract
The interface –log[H+] defined as pH′ of a mimic inner mitochondrial membrane is ∼3.9 at bulk pH ∼ 6.8, which affects cytochrome c activity.
The activities of biomolecules are affected by the proton concentrations at biological membranes. Here, we succeeded in evaluating the interface proton concentration (–log[H+] defined as pH′) of cardiolipin (CL)-enriched membrane models of the inner mitochondrial membrane (IMM) using a spiro-rhodamine-glucose molecule (RHG). According to fluorescence microscopy and 1H-NMR studies, RHG interacted with the Stern layer of the membrane. The acid/base equilibrium of RHG between its protonated open form (o-RHG) and deprotonated closed spiro-form (c-RHG) at the membrane interface was monitored with UV-vis absorption and fluorescence spectra. The interface pH′ of 25% cardiolipin (CL)-containing large unilamellar vesicles (LUVs), which possess similar lipid properties to those of the IMM, was estimated to be ∼3.9, when the bulk pH was similar to the mitochondrial intermembrane space pH (6.8). However, for the membranes containing mono-anionic lipids, the interface pH′ was estimated to be ∼5.3 at bulk pH 6.8, indicating that the local negative charges of the lipid headgroups in the lipid membranes are responsible for the deviation of the interface pH′ from the bulk pH. The peroxidase activity of cyt c increased 5–7 fold upon lowering the pH to 3.9–4.3 or adding CL-containing (10–25% of total lipids) LUVs compared to that at bulk pH 6.8, indicating that the pH′ decrease at the IMM interface from the bulk pH enhances the peroxidase activity of cyt c. The peroxidase activity of cyt c at the membrane interface of tetraoleoyl CL (TOCL)-enriched (50% of total lipids) LUVs was higher than that estimated from the interface pH′, while the peroxidase activity was similar to that estimated from the interface pH′ for tetramyristoyl CL (TMCL)-enriched LUVs, supporting the hypothesis that when interacting with TOCL (not TMCL), cyt c opens the heme crevice to substrates. The present simple methodology allows us to estimate the interface proton concentrations of complex biological membranes.
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Affiliation(s)
- Partha Pratim Parui
- Department of Chemistry , Jadavpur University , Kolkata 700032 , India . ; ; Tel: +91-9433490492.,Division of Materials Science , Nara Institute of Science and Technology , Nara 630-0192 , Japan
| | - Yeasmin Sarakar
- Department of Chemistry , Jadavpur University , Kolkata 700032 , India . ; ; Tel: +91-9433490492
| | - Rini Majumder
- Department of Chemistry , Jadavpur University , Kolkata 700032 , India . ; ; Tel: +91-9433490492
| | - Sanju Das
- Department of Chemistry , Jadavpur University , Kolkata 700032 , India . ; ; Tel: +91-9433490492.,Department of Chemistry , Maulana Azad College , Kolkata 700013 , India
| | - Hongxu Yang
- Division of Materials Science , Nara Institute of Science and Technology , Nara 630-0192 , Japan
| | - Kazuma Yasuhara
- Division of Materials Science , Nara Institute of Science and Technology , Nara 630-0192 , Japan
| | - Shun Hirota
- Division of Materials Science , Nara Institute of Science and Technology , Nara 630-0192 , Japan
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72
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The Role of Sodium Hydrogen Exchanger 1 in Dysregulation of Proton Dynamics and Reprogramming of Cancer Metabolism as a Sequela. Int J Mol Sci 2019; 20:ijms20153694. [PMID: 31357694 PMCID: PMC6696090 DOI: 10.3390/ijms20153694] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 07/23/2019] [Accepted: 07/25/2019] [Indexed: 12/15/2022] Open
Abstract
Cancer cells have an unusual regulation of hydrogen ion dynamics that are driven by poor vascularity perfusion, regional hypoxia, and increased glycolysis. All these forces synergize/orchestrate together to create extracellular acidity and intracellular alkalinity. Precisely, they lead to extracellular pH (pHe) values as low as 6.2 and intracellular pH values as high as 8. This unique pH gradient (∆pHi to ∆pHe) across the cell membrane increases as the tumor progresses, and is markedly displaced from the electrochemical equilibrium of protons. These unusual pH dynamics influence cancer cell biology, including proliferation, metastasis, and metabolic adaptation. Warburg metabolism with increased glycolysis, even in the presence of Oxygen with the subsequent reduction in Krebs’ cycle, is a common feature of most cancers. This metabolic reprogramming confers evolutionary advantages to cancer cells by enhancing their resistance to hypoxia, to chemotherapy or radiotherapy, allowing rapid production of biological building blocks that support cellular proliferation, and shielding against damaging mitochondrial free radicals. In this article, we highlight the interconnected roles of dysregulated pH dynamics in cancer initiation, progression, adaptation, and in determining the programming and re-programming of tumor cell metabolism.
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73
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Slowly Reducible Genetically Encoded Green Fluorescent Indicator for In Vivo and Ex Vivo Visualization of Hydrogen Peroxide. Int J Mol Sci 2019; 20:ijms20133138. [PMID: 31252566 PMCID: PMC6650888 DOI: 10.3390/ijms20133138] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/19/2019] [Accepted: 06/25/2019] [Indexed: 12/16/2022] Open
Abstract
Hydrogen peroxide (H2O2) plays an important role in modulating cell signaling and homeostasis in live organisms. The HyPer family of genetically encoded indicators allows the visualization of H2O2 dynamics in live cells within a limited field of view. The visualization of H2O2 within a whole organism with a single cell resolution would benefit from a slowly reducible fluorescent indicator that integrates the H2O2 concentration over desired time scales. This would enable post hoc optical readouts in chemically fixed samples. Herein, we report the development and characterization of NeonOxIrr, a genetically encoded green fluorescent indicator, which rapidly increases fluorescence brightness upon reaction with H2O2, but has a low reduction rate. NeonOxIrr is composed of circularly permutated mNeonGreen fluorescent protein fused to the truncated OxyR transcription factor isolated from E. coli. When compared in vitro to a standard in the field, HyPer3 indicator, NeonOxIrr showed 5.9-fold higher brightness, 15-fold faster oxidation rate, 5.9-fold faster chromophore maturation, similar intensiometric contrast (2.8-fold), 2-fold lower photostability, and significantly higher pH stability both in reduced (pKa of 5.9 vs. ≥7.6) and oxidized states (pKa of 5.9 vs.≥ 7.9). When expressed in the cytosol of HEK293T cells, NeonOxIrr demonstrated a 2.3-fold dynamic range in response to H2O2 and a 44 min reduction half-time, which were 1.4-fold lower and 7.6-fold longer than those for HyPer3. We also demonstrated and characterized the NeonOxIrr response to H2O2 when the sensor was targeted to the matrix and intermembrane space of the mitochondria, nucleus, cell membranes, peroxisomes, Golgi complex, and endoplasmic reticulum of HEK293T cells. NeonOxIrr could reveal endogenous reactive oxygen species (ROS) production in HeLa cells induced with staurosporine but not with thapsigargin or epidermal growth factor. In contrast to HyPer3, NeonOxIrr could visualize optogenetically produced ROS in HEK293T cells. In neuronal cultures, NeonOxIrr preserved its high 3.2-fold dynamic range to H2O2 and slow 198 min reduction half-time. We also demonstrated in HeLa cells that NeonOxIrr preserves a 1.7-fold ex vivo dynamic range to H2O2 upon alkylation with N-ethylmaleimide followed by paraformaldehyde fixation. The same alkylation-fixation procedure in the presence of NP-40 detergent allowed ex vivo detection of H2O2 with 1.5-fold contrast in neuronal cultures and in the cortex of the mouse brain. The slowly reducible H2O2 indicator NeonOxIrr can be used for both the in vivo and ex vivo visualization of ROS. Expanding the family of fixable indicators may be a promising strategy to visualize biological processes at a single cell resolution within an entire organism.
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74
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Webb M, Sideris DP, Biddle M. Modulation of mitochondrial dysfunction for treatment of disease. Bioorg Med Chem Lett 2019; 29:1270-1277. [DOI: 10.1016/j.bmcl.2019.03.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/21/2019] [Accepted: 03/25/2019] [Indexed: 12/18/2022]
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75
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Live-Cell Imaging of Physiologically Relevant Metal Ions Using Genetically Encoded FRET-Based Probes. Cells 2019; 8:cells8050492. [PMID: 31121936 PMCID: PMC6562680 DOI: 10.3390/cells8050492] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/17/2019] [Accepted: 05/21/2019] [Indexed: 01/02/2023] Open
Abstract
Essential biochemical reactions and processes within living organisms are coupled to subcellular fluctuations of metal ions. Disturbances in cellular metal ion homeostasis are frequently associated with pathological alterations, including neurotoxicity causing neurodegeneration, as well as metabolic disorders or cancer. Considering these important aspects of the cellular metal ion homeostasis in health and disease, measurements of subcellular ion signals are of broad scientific interest. The investigation of the cellular ion homeostasis using classical biochemical methods is quite difficult, often even not feasible or requires large cell numbers. Here, we report of genetically encoded fluorescent probes that enable the visualization of metal ion dynamics within individual living cells and their organelles with high temporal and spatial resolution. Generally, these probes consist of specific ion binding domains fused to fluorescent protein(s), altering their fluorescent properties upon ion binding. This review focuses on the functionality and potential of these genetically encoded fluorescent tools which enable monitoring (sub)cellular concentrations of alkali metals such as K+, alkaline earth metals including Mg2+ and Ca2+, and transition metals including Cu+/Cu2+ and Zn2+. Moreover, we discuss possible approaches for the development and application of novel metal ion biosensors for Fe2+/Fe3+, Mn2+ and Na+.
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76
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Degradation of D-2-hydroxyglutarate in the presence of isocitrate dehydrogenase mutations. Sci Rep 2019; 9:7436. [PMID: 31092874 PMCID: PMC6520482 DOI: 10.1038/s41598-019-43891-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 03/20/2019] [Indexed: 11/08/2022] Open
Abstract
D-2-Hydroxyglutarate (D-2-HG) is regarded as an oncometabolite. It is found at elevated levels in certain malignancies such as acute myeloid leukaemia and glioma. It is produced by a mutated isocitrate dehydrogenase IDH1/2, a low-affinity/high-capacity enzyme. Its degradation, in contrast, is catalysed by the high-affinity/low-capacity enzyme D-2-hydroxyglutarate dehydrogenase (D2HDH). So far, it has not been proven experimentally that the accumulation of D-2-HG in IDH mutant cells is the result of its insufficient degradation by D2HDH. Therefore, we developed an LC-MS/MS-based enzyme activity assay that measures the temporal drop in substrate and compared this to the expression of D2HDH protein as measured by Western blot. Our data clearly indicate, that the maximum D-2-HG degradation rate by D2HDH is reached in vivo, as vmax is low in comparison to production of D-2-HG by mutant IDH1/2. The latter seems to be limited only by substrate availability. Further, incubation of IDH wild type cells for up to 48 hours with 5 mM D-2-HG did not result in a significant increase in either D2HDH protein abundance or enzyme activity.
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77
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Singh N, Mugesh G. CeVO
4
Nanozymes Catalyze the Reduction of Dioxygen to Water without Releasing Partially Reduced Oxygen Species. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201903427] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Namrata Singh
- Department of Inorganic and Physical ChemistryIndian Institute of Science Bangalore- 560012 India
- Centre for Nanoscience and EngineeringIndian Institute of Science Bangalore- 560012 India
| | - Govindasamy Mugesh
- Department of Inorganic and Physical ChemistryIndian Institute of Science Bangalore- 560012 India
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78
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Singh N, Mugesh G. CeVO 4 Nanozymes Catalyze the Reduction of Dioxygen to Water without Releasing Partially Reduced Oxygen Species. Angew Chem Int Ed Engl 2019; 58:7797-7801. [PMID: 30950157 DOI: 10.1002/anie.201903427] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Indexed: 12/25/2022]
Abstract
In this study, we report a remarkably active CeVO4 nanozyme that functionally mimics cytochrome c oxidase (CcO), the terminal enzyme in the respiratory electron transport chain, by catalyzing a four-electron reduction of dioxygen to water. The nanozyme catalyzes the reaction by using cytochrome c (Cyt c), the biological electron donor for CcO, at physiologically relevant pH. The CcO activity of the CeVO4 nanozymes depends on the relative ratio of surface Ce3+ /Ce4+ ions, the presence of V5+ and the surface-Cyt c interactions. The complete reduction of oxygen to water takes place without release of any partially reduced oxygen species (PROS) such as superoxide, peroxide and hydroxyl radicals.
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Affiliation(s)
- Namrata Singh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore-, 560012, India
- Centre for Nanoscience and Engineering, Indian Institute of Science, Bangalore-, 560012, India
| | - Govindasamy Mugesh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore-, 560012, India
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79
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Burgstaller S, Bischof H, Gensch T, Stryeck S, Gottschalk B, Ramadani-Muja J, Eroglu E, Rost R, Balfanz S, Baumann A, Waldeck-Weiermair M, Hay JC, Madl T, Graier WF, Malli R. pH-Lemon, a Fluorescent Protein-Based pH Reporter for Acidic Compartments. ACS Sens 2019; 4:883-891. [PMID: 30864782 PMCID: PMC6488996 DOI: 10.1021/acssensors.8b01599] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Distinct subcellular pH levels, especially in lysosomes and endosomes, are essential for the degradation, modification, sorting, accumulation, and secretion of macromolecules. Here, we engineered a novel genetically encoded pH probe by fusing the pH-stable cyan fluorescent protein (FP) variant, mTurquoise2, to the highly pH-sensitive enhanced yellow fluorescent protein, EYFP. This approach yielded a ratiometric biosensor-referred to as pH-Lemon-optimized for live imaging of distinct pH conditions within acidic cellular compartments. Protonation of pH-Lemon under acidic conditions significantly decreases the yellow fluorescence while the cyan fluorescence increases due to reduced Förster resonance energy transfer (FRET) efficiency. Because of its freely reversible and ratiometric responses, pH-Lemon represents a fluorescent biosensor for pH dynamics. pH-Lemon also shows a sizable pH-dependent fluorescence lifetime change that can be used in fluorescence lifetime imaging microscopy as an alternative observation method for the study of pH in acidic cellular compartments. Fusion of pH-Lemon to the protein microtubule-associated protein 1A/1B-light chain 3B (LC3B), a specific marker of autophagic membranes, resulted in its targeting within autolysosomes of HeLa cells. Moreover, fusion of pH-Lemon to a glycophosphatidylinositol (GPI) anchor allowed us to monitor the entire luminal space of the secretory pathway and the exoplasmic leaflet of the plasma membrane. Utilizing this new pH probe, we revealed neutral and acidic vesicles and substructures inside cells, highlighting compartments of distinct pH throughout the endomembrane system. These data demonstrate, that this novel pH sensor, pH-Lemon, is very suitable for the study of local pH dynamics of subcellular microstructures in living cells.
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Affiliation(s)
- Sandra Burgstaller
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Helmut Bischof
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Thomas Gensch
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Sarah Stryeck
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Benjamin Gottschalk
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Jeta Ramadani-Muja
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Emrah Eroglu
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Rene Rost
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Sabine Balfanz
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Arnd Baumann
- Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Markus Waldeck-Weiermair
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Jesse C. Hay
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
- Division of Biological Sciences and Center for Structural and Functional Neuroscience, The University of Montana, 32 Campus Drive, HS410, Missoula 59812-4824, Montana United States
| | - Tobias Madl
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
- BioTechMed Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Wolfgang F. Graier
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
- BioTechMed Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Roland Malli
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
- BioTechMed Graz, Mozartgasse 12/II, 8010 Graz, Austria
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80
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Xiao H, Dong Y, Zhou J, Zhou Z, Wu X, Wang R, Miao Z, Liu Y, Zhuo S. Monitoring mitochondrial pH with a hemicyanine-based ratiometric fluorescent probe. Analyst 2019; 144:3422-3427. [PMID: 31011741 DOI: 10.1039/c9an00422j] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mitochondria as essential organelles play critical roles in cellular metabolism. Mitochondrial pH is a vital parameter that directly affects the unique function of mitochondria. Herein, we present a new ratiometric fluorescent probe M-pH for monitoring the pH within the mitochondria. M-pH consists of a stable and large π-electron conjugated merocyanine system. The lipophilic cationic benzyl group will facilitate the accumulation of M-pH in mitochondria. The phenol unit is the recognition moiety, achieving the ratiometric sensing of pH changes. The experimental results indicate that M-pH displays ratiometric fluorescence response to different pH values. Meanwhile, M-pH shows negligible response to common species, and has high stability and low cytotoxicity. In biological experiments, M-pH can solely accumulate in mitochondria and visualize the pH changes during mitophagy and cell apoptosis. We thus believe that M-pH has great potential as a practical tool for real-time monitoring of pH changes of mitochondria, contributing to revealing the pathogenesis of mitochondrial pH associated diseases.
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Affiliation(s)
- Haibin Xiao
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Yaqi Dong
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Jin Zhou
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Ziyan Zhou
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Xiaozhong Wu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Rongzhou Wang
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Zhichao Miao
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Yuying Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
| | - Shuping Zhuo
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, P. R. China.
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81
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Oviedo-Rouco S, Castro MA, Alvarez-Paggi D, Spedalieri C, Tortora V, Tomasina F, Radi R, Murgida DH. The alkaline transition of cytochrome c revisited: Effects of electrostatic interactions and tyrosine nitration on the reaction dynamics. Arch Biochem Biophys 2019; 665:96-106. [DOI: 10.1016/j.abb.2019.02.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 02/18/2019] [Accepted: 02/19/2019] [Indexed: 12/19/2022]
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82
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Hawrysh PJ, Buck LT. Mitochondrial matrix pH acidifies during anoxia and is maintained by the F 1F o-ATPase in anoxia-tolerant painted turtle cortical neurons. FEBS Open Bio 2019; 9:571-581. [PMID: 30984533 PMCID: PMC6443863 DOI: 10.1002/2211-5463.12612] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 01/18/2019] [Accepted: 02/05/2019] [Indexed: 12/19/2022] Open
Abstract
The western painted turtle (Chrysemys picta bellii) can survive extended periods of anoxia via a series of mechanisms that serve to reduce its energetic needs. Central to these mechanisms is the response of mitochondria, which depolarize in response to anoxia in turtle pyramidal neurons due to an influx of K+. It is currently unknown how mitochondrial matrix pH is affected by this response and we hypothesized that matrix pH acidifies during anoxia due to increased K+/H+ exchanger activity. Inhibition of K+/H+ exchange via quinine led to a collapse of mitochondrial membrane potential (Ψm) during oxygenated conditions in turtle cortical neurons, as indicated by rhodamine‐123 fluorescence, and this occurred twice as quickly during anoxia which indicates an elevation in K+ conductance. Mitochondrial matrix pH acidified during anoxia, as indicated by SNARF‐1 fluorescence imaged via confocal microscopy, and further acidification occurred during anoxia when the F1Fo‐ATPase was inhibited with oligomycin‐A, indicating that ΔpH collapse is prevented during anoxic conditions. Collectively, these results indicate that the mitochondrial proton electrochemical gradient is actively preserved during anoxia to prevent a collapse of Ψm and ΔpH.
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Affiliation(s)
| | - Leslie Thomas Buck
- Department of Cell and Systems Biology University of Toronto Canada.,Department of Ecology and Evolutionary Biology University of Toronto Canada
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83
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Trombetti F, Pagliarani A, Ventrella V, Algieri C, Nesci S. Crucial aminoacids in the F O sector of the F 1F O-ATP synthase address H + across the inner mitochondrial membrane: molecular implications in mitochondrial dysfunctions. Amino Acids 2019; 51:579-587. [PMID: 30798467 DOI: 10.1007/s00726-019-02710-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 02/09/2019] [Indexed: 12/14/2022]
Abstract
The eukaryotic F1FO-ATP synthase/hydrolase activity is coupled to H+ translocation through the inner mitochondrial membrane. According to a recent model, two asymmetric H+ half-channels in the a subunit translate a transmembrane vertical H+ flux into the rotor rotation required for ATP synthesis/hydrolysis. Along the H+ pathway, conserved aminoacid residues, mainly glutamate, address H+ both in the downhill and uphill transmembrane movements to synthesize or hydrolyze ATP, respectively. Point mutations responsible for these aminoacid changes affect H+ transfer through the membrane and, as a cascade, result in mitochondrial dysfunctions and related pathologies. The involvement of specific aminoacid residues in driving H+ along their transmembrane pathway within a subunit, sustained by the literature and calculated data, leads to depict a model consistent with some mitochondrial disorders.
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Affiliation(s)
- Fabiana Trombetti
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy
| | - Alessandra Pagliarani
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy.
| | - Vittoria Ventrella
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy
| | - Cristina Algieri
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy
| | - Salvatore Nesci
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy
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84
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Chareyron I, Wall C, Thevenet J, Santo-Domingo J, Wiederkehr A. Cellular stress is a prerequisite for glucose-induced mitochondrial matrix alkalinization in pancreatic β-cells. Mol Cell Endocrinol 2019; 481:71-83. [PMID: 30476561 DOI: 10.1016/j.mce.2018.11.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 11/20/2018] [Accepted: 11/22/2018] [Indexed: 11/24/2022]
Abstract
Changes in mitochondrial and cytosolic pH alter the chemical gradient across the inner mitochondrial membrane. The proton chemical gradient contributes to mitochondrial ATP synthesis as well as the uptake and release of metabolites and ions from the organelle. Here mitochondrial pH and ΔpH were studied for the first time in human pancreatic β-cells. Adenoviruses were used for rat insulin promoter dependent expression of the pH sensor SypHer targeted to either the mitochondrial matrix or the cytosol. The matrix pH in resting human β-cells is low (pH = 7.50 ± SD 0.17) compared to published values in other cell types. Consequently, the ΔpH of β-cells mitochondria is small. Glucose stimulation consistently resulted in acidification of the matrix pH in INS-1E insulinoma cells and β-cells in intact human islets or islet monolayer cultures. We registered acidification with similar kinetics but of slightly smaller amplitude in the cytosol of β-cells, thus glucose stimulation further reduced the ΔpH. Infection of human islets with high levels of adenoviruses caused the mitochondrial pH to increase. The apoptosis inducer and broad-spectrum kinase inhibitor staurosporine had similar effects on pH homeostasis. Although staurosporine alone does not affect the mitochondrial pH, glucose slightly increases the matrix pH of staurosporine treated cells. These two cellular stressors alter the normal mitochondrial pH response to glucose in pancreatic β-cells.
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Affiliation(s)
- Isabelle Chareyron
- Mitochondrial Function, Nestlé Institute of Health Sciences, 1015, Lausanne, Switzerland
| | - Christopher Wall
- Mitochondrial Function, Nestlé Institute of Health Sciences, 1015, Lausanne, Switzerland
| | - Jonathan Thevenet
- Mitochondrial Function, Nestlé Institute of Health Sciences, 1015, Lausanne, Switzerland
| | - Jaime Santo-Domingo
- Mitochondrial Function, Nestlé Institute of Health Sciences, 1015, Lausanne, Switzerland
| | - Andreas Wiederkehr
- Mitochondrial Function, Nestlé Institute of Health Sciences, 1015, Lausanne, Switzerland.
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85
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Jiang YY, Zhou ZF, Zhu YJ, Chen FF, Lu BQ, Cao WT, Zhang YG, Cai ZD, Chen F. Enzymatic Reaction Generates Biomimic Nanominerals with Superior Bioactivity. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1804321. [PMID: 30417599 DOI: 10.1002/smll.201804321] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Indexed: 05/22/2023]
Abstract
In vivo mineralization is a multistep process involving mineral-protein complexes and various metastable compounds in vertebrates. In this complex process, the minerals produced in the mitochondrial matrix play a critical role in initiating extracellular mineralization. However, the functional mechanisms of the mitochondrial minerals are still a mystery. Herein, an in vitro enzymatic reaction strategy is reported for the generation of biomimic amorphous calcium phosphate (EACP) nanominerals by an alkaline phosphatase (ALP)-catalyzed hydrolysis of adenosine triphosphate (ATP) in a weakly alkalescent aqueous condition (pH 8.0-8.5), which is partially similar to the mitochondrial environment. Significantly, the EACP nanomineral obviously promotes autophagy and osteogenic differentiation of human bone marrow-derived mesenchymal stem cells by activating an AMPK related pathway, and displays a high performance in promoting bone regeneration. These results provide in vitro evidence for the effect of ATP on the formation and stabilization of the mineral in the mineralization process, demonstrating a potential strategy for the preparation of the biomimic mineral for treating bone related diseases.
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Affiliation(s)
- Ying-Ying Jiang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
- Department of Orthopedics, Spinal Pain Research Institute, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, P. R. China
| | - Zi-Fei Zhou
- Department of Orthopedics, Spinal Pain Research Institute, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, P. R. China
- Department of Orthopedic Surgery, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, 200080, P. R. China
| | - Ying-Jie Zhu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
| | - Fei-Fei Chen
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
| | - Bing-Qiang Lu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
| | - Wen-Tao Cao
- Department of Orthopedics, Spinal Pain Research Institute, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, P. R. China
| | - Yong-Gang Zhang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
| | - Zheng-Dong Cai
- Department of Orthopedic Surgery, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, 200080, P. R. China
| | - Feng Chen
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
- Department of Orthopedics, Spinal Pain Research Institute, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, P. R. China
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86
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Urbanczyk S, Stein M, Schuh W, Jäck HM, Mougiakakos D, Mielenz D. Regulation of Energy Metabolism during Early B Lymphocyte Development. Int J Mol Sci 2018; 19:E2192. [PMID: 30060475 PMCID: PMC6121686 DOI: 10.3390/ijms19082192] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 07/25/2018] [Indexed: 01/03/2023] Open
Abstract
The most important feature of humoral immunity is the adaptation of the diversity of newly generated B cell receptors, that is, the antigen receptor repertoire, to the body's own and foreign structures. This includes the transient propagation of B progenitor cells and B cells, which possess receptors that are positively selected via anabolic signalling pathways under highly competitive conditions. The metabolic regulation of early B-cell development thus has important consequences for the expansion of normal or malignant pre-B cell clones. In addition, cellular senescence programs based on the expression of B cell identity factors, such as Pax5, act to prevent excessive proliferation and cellular deviation. Here, we review the basic mechanisms underlying the regulation of glycolysis and oxidative phosphorylation during early B cell development in bone marrow. We focus on the regulation of glycolysis and mitochondrial oxidative phosphorylation at the transition from non-transformed pro- to pre-B cells and discuss some ongoing issues. We introduce Swiprosin-2/EFhd1 as a potential regulator of glycolysis in pro-B cells that has also been linked to Ca2+-mediated mitoflashes. Mitoflashes are bioenergetic mitochondrial events that control mitochondrial metabolism and signalling in both healthy and disease states. We discuss how Ca2+ fluctuations in pro- and pre-B cells may translate into mitoflashes in early B cells and speculate about the consequences of these changes.
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Affiliation(s)
- Sophia Urbanczyk
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Merle Stein
- Department of Internal Medicine V, University Hospital, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Wolfgang Schuh
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Hans-Martin Jäck
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Dimitrios Mougiakakos
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, 89081 Ulm, Germany.
| | - Dirk Mielenz
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
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87
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Enoch SJ, Schultz TW, Popova IG, Vasilev KG, Mekenyan OG. Development of a Decision Tree for Mitochondrial Dysfunction: Uncoupling of Oxidative Phosphorylation. Chem Res Toxicol 2018; 31:814-820. [DOI: 10.1021/acs.chemrestox.8b00132] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Steven J. Enoch
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, L3 3AF Liverpool, England
| | - Terry W. Schultz
- College of Veterinary Medicine, The University of Tennessee, 2407 River Drive, Knoxville, Tennessee 37996-4500, United States
| | - Ioanna G. Popova
- Laboratory of Mathematical Chemistry (LMC), As. Zlatarov University, Bourgas 8000, Bulgaria
| | - Krasimir G. Vasilev
- Laboratory of Mathematical Chemistry (LMC), As. Zlatarov University, Bourgas 8000, Bulgaria
| | - Ovanes G. Mekenyan
- Laboratory of Mathematical Chemistry (LMC), As. Zlatarov University, Bourgas 8000, Bulgaria
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88
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Freedman H, Winter P, Tuszynski J, Tyrrell DL, Houghton M. A computational approach for predicting off-target toxicity of antiviral ribonucleoside analogues to mitochondrial RNA polymerase. J Biol Chem 2018; 293:9696-9705. [PMID: 29739852 DOI: 10.1074/jbc.ra118.002588] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 05/04/2018] [Indexed: 12/18/2022] Open
Abstract
In the development of antiviral drugs that target viral RNA-dependent RNA polymerases, off-target toxicity caused by the inhibition of the human mitochondrial RNA polymerase (POLRMT) is a major liability. Therefore, it is essential that all new ribonucleoside analogue drugs be accurately screened for POLRMT inhibition. A computational tool that can accurately predict NTP binding to POLRMT could assist in evaluating any potential toxicity and in designing possible salvaging strategies. Using the available crystal structure of POLRMT bound to an RNA transcript, here we created a model of POLRMT with an NTP molecule bound in the active site. Furthermore, we implemented a computational screening procedure that determines the relative binding free energy of an NTP analogue to POLRMT by free energy perturbation (FEP), i.e. a simulation in which the natural NTP molecule is slowly transformed into the analogue and back. In each direction, the transformation was performed over 40 ns of simulation on our IBM Blue Gene Q supercomputer. This procedure was validated across a panel of drugs for which experimental dissociation constants were available, showing that NTP relative binding free energies could be predicted to within 0.97 kcal/mol of the experimental values on average. These results demonstrate for the first time that free-energy simulation can be a useful tool for predicting binding affinities of NTP analogues to a polymerase. We expect that our model, together with similar models of viral polymerases, will be very useful in the screening and future design of NTP inhibitors of viral polymerases that have no mitochondrial toxicity.
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Affiliation(s)
- Holly Freedman
- From the Li Ka Shing Applied Virology Institute, Department of Medical Microbiology and Immunology and
| | - Philip Winter
- the Department of Oncology, University of Alberta, Edmonton, Alberta T6G 2R7, Canada
| | - Jack Tuszynski
- the Department of Oncology, University of Alberta, Edmonton, Alberta T6G 2R7, Canada.,the Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada and
| | - D Lorne Tyrrell
- From the Li Ka Shing Applied Virology Institute, Department of Medical Microbiology and Immunology and
| | - Michael Houghton
- From the Li Ka Shing Applied Virology Institute, Department of Medical Microbiology and Immunology and
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89
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Holmila RJ, Vance SA, Chen X, Wu H, Shukla K, Bharadwaj MS, Mims J, Wary Z, Marrs G, Singh R, Molina AJ, Poole LB, King SB, Furdui CM. Mitochondria-targeted Probes for Imaging Protein Sulfenylation. Sci Rep 2018; 8:6635. [PMID: 29703899 PMCID: PMC5923234 DOI: 10.1038/s41598-018-24493-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 03/27/2018] [Indexed: 01/03/2023] Open
Abstract
Mitochondrial reactive oxygen species (ROS) are essential regulators of cellular signaling, metabolism and epigenetics underlying the pathophysiology of numerous diseases. Despite the critical function of redox regulation in mitochondria, currently there are limited methods available to monitor protein oxidation in this key subcellular organelle. Here, we describe compounds for imaging sulfenylated proteins in mitochondria: DCP-NEt2-Coumarin (DCP-NEt2C) and rhodamine-based DCP-Rho1. Side-by-side comparison studies are presented on the reactivity of DCP-NEt2C and DCP-Rho1 with a model protein sulfenic acid (AhpC-SOH) and mitochondrial localization to identify optimized experimental conditions for labeling and visualization of protein sulfenylation that would be independent of mitochondria membrane potential and would not impact mitochondrial function. These probes are applied to image mitochondrial protein sulfenylation under conditions of serum starvation and in a cell culture model of lung cancer exposed to ionizing radiation and silver nanoparticles, agents serving dual functions as environmental stressors and cancer therapeutics.
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Affiliation(s)
- Reetta J Holmila
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Stephen A Vance
- Department of Chemistry, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Xiaofei Chen
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Hanzhi Wu
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Kirtikar Shukla
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Manish S Bharadwaj
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Jade Mims
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Zack Wary
- Department of Chemistry, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Glen Marrs
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Ravi Singh
- Department of Cancer Biology, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Anthony J Molina
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - Leslie B Poole
- Department of Biochemistry, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA
| | - S Bruce King
- Department of Chemistry, Wake Forest University, Winston-Salem, NC, 27109, USA
| | - Cristina M Furdui
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest University Health Sciences, Winston-Salem, NC, 27157, USA.
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90
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Transcriptomic characterization of MRI contrast with focus on the T1-w/T2-w ratio in the cerebral cortex. Neuroimage 2018; 174:504-517. [PMID: 29567503 PMCID: PMC6450807 DOI: 10.1016/j.neuroimage.2018.03.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 03/12/2018] [Accepted: 03/14/2018] [Indexed: 01/24/2023] Open
Abstract
Magnetic resonance (MR) images of the brain are of immense clinical and research utility. At the atomic and subatomic levels, the sources of MR signals are well understood. However, we lack a comprehensive understanding of the macromolecular correlates of MR signal contrast. To address this gap, we used genome-wide measurements to correlate gene expression with MR signal intensity across the cerebral cortex in the Allen Human Brain Atlas (AHBA). We focused on the ratio of T1-weighted and T2-weighted intensities (T1-w/T2-w ratio image), which is considered to be a useful proxy for myelin content. As expected, we found enrichment of positive correlations between myelin-associated genes and the ratio image, supporting its use as a myelin marker. Genome-wide, there was an association with protein mass, with genes coding for heavier proteins expressed in regions with high T1-w/T2-w values. Oligodendrocyte gene markers were strongly correlated with the T1-w/T2-w ratio, but this was not driven by myelin-associated genes. Mitochondrial genes exhibit the strongest relationship, showing higher expression in regions with low T1-w/T2-w ratio. This may be due to the pH gradient in mitochondria as genes up-regulated by pH in the brain were also highly correlated with the ratio. While we corroborate associations with myelin and synaptic plasticity, differences in the T1-w/T2-w ratio across the cortex are more strongly linked to molecule size, oligodendrocyte markers, mitochondria, and pH. We evaluate correlations between AHBA transcriptomic measurements and a group averaged T1-w/T2-w ratio image, showing agreement with in-sample results. Expanding our analysis to the whole brain results in strong positive T1-w/T2-w correlations for immune system, inflammatory disease, and microglia marker genes. Genes with negative correlations were enriched for neuron markers and synaptic plasticity genes. Lastly, our findings are similar when performed on T1-w or inverted T2-w intensities alone. These results provide a molecular characterization of MR contrast that will aid interpretation of future MR studies of the brain.
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91
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Kirscht A, Sonntag Y, Kjellbom P, Johanson U. A structural preview of aquaporin 8 via homology modeling of seven vertebrate isoforms. BMC STRUCTURAL BIOLOGY 2018; 18:2. [PMID: 29454339 PMCID: PMC5816522 DOI: 10.1186/s12900-018-0081-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 01/25/2018] [Indexed: 11/10/2022]
Abstract
Background Aquaporins (AQPs) facilitate the passage of small neutral polar molecules across membranes of the cell. In animals there are four distinct AQP subfamilies, whereof AQP8 homologues constitute one of the smallest subfamilies with just one member in man. AQP8 conducts water, ammonia, urea, glycerol and H2O2 through various membranes of animal cells. This passive channel has been connected to a number of phenomena, such as volume change of mitochondria, ammonia neurotoxicity, and mitochondrial dysfunction related to oxidative stress. Currently, there is no experimentally determined structure of an AQP8, hence the structural understanding of this subfamily is limited. The recently solved structure of the plant AQP, AtTIP2;1, which has structural and functional features in common with AQP8s, has opened up for construction of homology models that are likely to be more accurate than previous models. Results Here we present homology models of seven vertebrate AQP8s. Modeling based on the AtTIP2;1 structure alone resulted in reasonable models except for the pore being blocked by a phenylalanine that is not present in AtTIP2;1. To achieve an open pore, these models were supplemented with models based on the bacterial water specific AQP, EcAqpZ, creating a chimeric monomeric model for each AQP8 isoform. The selectivity filter (also named the aromatic/arginine region), which defines the permeant substrate profile, comprises five amino acid residues in AtTIP2;1, including a histidine coming from loop C. Compared to AtTIP2;1, the selectivity filters of modelled AQP8s only deviates in that they are slightly more narrow and more hydrophobic due to a phenylalanine replacing the histidine from loop C. Interestingly, the models do not exclude the existence of a side pore beneath loop C similar to that described in the structure of AtTIP2;1. Conclusions Our models concur that AQP8s are likely to have an AtTIP2;1-like selectivity filter. The detailed description of the expected configuration of residues in the selectivity filters of AQP8s provides an excellent starting point for planning of as well as rationalizing the outcome of mutational studies. Our strategy to compile hybrid models based on several templates may prove useful also for other AQPs for which structural information is limited. Electronic supplementary material The online version of this article (10.1186/s12900-018-0081-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Andreas Kirscht
- Division of Biochemistry and Structural Biology, Center for Molecular Protein Science, Department of Chemistry, Lund University, Box 124, SE-221 00, Lund, Sweden
| | - Yonathan Sonntag
- Division of Biochemistry and Structural Biology, Center for Molecular Protein Science, Department of Chemistry, Lund University, Box 124, SE-221 00, Lund, Sweden
| | - Per Kjellbom
- Division of Biochemistry and Structural Biology, Center for Molecular Protein Science, Department of Chemistry, Lund University, Box 124, SE-221 00, Lund, Sweden
| | - Urban Johanson
- Division of Biochemistry and Structural Biology, Center for Molecular Protein Science, Department of Chemistry, Lund University, Box 124, SE-221 00, Lund, Sweden.
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92
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Ali I, Conrad RJ, Verdin E, Ott M. Lysine Acetylation Goes Global: From Epigenetics to Metabolism and Therapeutics. Chem Rev 2018; 118:1216-1252. [PMID: 29405707 PMCID: PMC6609103 DOI: 10.1021/acs.chemrev.7b00181] [Citation(s) in RCA: 222] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Post-translational acetylation of lysine residues has emerged as a key regulatory mechanism in all eukaryotic organisms. Originally discovered in 1963 as a unique modification of histones, acetylation marks are now found on thousands of nonhistone proteins located in virtually every cellular compartment. Here we summarize key findings in the field of protein acetylation over the past 20 years with a focus on recent discoveries in nuclear, cytoplasmic, and mitochondrial compartments. Collectively, these findings have elevated protein acetylation as a major post-translational modification, underscoring its physiological relevance in gene regulation, cell signaling, metabolism, and disease.
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Affiliation(s)
- Ibraheem Ali
- Gladstone Institute of Virology and Immunology, San Francisco, California 94158, United States
- University of California, San Francisco, Department of Medicine, San Francisco, California 94158, United States
| | - Ryan J. Conrad
- Gladstone Institute of Virology and Immunology, San Francisco, California 94158, United States
- University of California, San Francisco, Department of Medicine, San Francisco, California 94158, United States
| | - Eric Verdin
- Buck Institute for Research on Aging, Novato, California 94945, United States
| | - Melanie Ott
- Gladstone Institute of Virology and Immunology, San Francisco, California 94158, United States
- University of California, San Francisco, Department of Medicine, San Francisco, California 94158, United States
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93
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Lin B, Fan L, Ge J, Zhang W, Zhang C, Dong C, Shuang S. A naphthalene-based fluorescent probe with a large Stokes shift for mitochondrial pH imaging. Analyst 2018; 143:5054-5060. [DOI: 10.1039/c8an01371c] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A naphthalene-based fluorescent pH probe with a pKa of 8.8 for imaging mitochondrial pH changes in live cells.
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Affiliation(s)
- Bo Lin
- College of Chemistry and Chemical Engineering
- Shanxi University
- Taiyuan 030006
- China
| | - Li Fan
- Institute of Environmental Science
- Shanxi University
- Taiyuan 030006
- China
| | - Jinyin Ge
- College of Chemistry and Chemical Engineering
- Shanxi University
- Taiyuan 030006
- China
| | - Wenjia Zhang
- College of Chemistry and Chemical Engineering
- Shanxi University
- Taiyuan 030006
- China
| | - Caihong Zhang
- College of Chemistry and Chemical Engineering
- Shanxi University
- Taiyuan 030006
- China
| | - Chuan Dong
- Institute of Environmental Science
- Shanxi University
- Taiyuan 030006
- China
| | - Shaomin Shuang
- College of Chemistry and Chemical Engineering
- Shanxi University
- Taiyuan 030006
- China
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94
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Jung Y, Jung J, Huh Y, Kim D. Benzo[ g]coumarin-Based Fluorescent Probes for Bioimaging Applications. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2018; 2018:5249765. [PMID: 30013807 PMCID: PMC6022312 DOI: 10.1155/2018/5249765] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 04/22/2018] [Indexed: 05/12/2023]
Abstract
Benzo[g]coumarins, which consist of coumarins fused with other aromatic units in the linear shape, have recently emerged as an interesting fluorophore in the bioimaging research. The pi-extended skeleton with the presence of electron-donating and electron-withdrawing substituents from the parent coumarins changes the basic photophysical parameters such as absorption and fluorescence emission significantly. Most of the benzo[g]coumarin analogues show red/far-red fluorescence emission with high two-photon absorbing property that can be applicable for the two-photon microscopy (TPM) imaging. In this review, we summarized the recently developed benzo[g]coumarin analogues including photophysical properties, synthesis, and applications for molecular probes that can sense biologically important species such as metal ions, cell organs, reactive species, and disease biomarkers.
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Affiliation(s)
- Yuna Jung
- Department of Biomedical Science, Graduate School, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
| | - Junyang Jung
- Department of Biomedical Science, Graduate School, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
- Department of Anatomy and Neurobiology, College of Medicine, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
| | - Youngbuhm Huh
- Department of Biomedical Science, Graduate School, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
- Department of Anatomy and Neurobiology, College of Medicine, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
| | - Dokyoung Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
- Department of Anatomy and Neurobiology, College of Medicine, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
- Center for Converging Humanities, Kyung Hee University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
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95
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Guidelines on experimental methods to assess mitochondrial dysfunction in cellular models of neurodegenerative diseases. Cell Death Differ 2017; 25:542-572. [PMID: 29229998 PMCID: PMC5864235 DOI: 10.1038/s41418-017-0020-4] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/06/2017] [Accepted: 10/12/2017] [Indexed: 01/22/2023] Open
Abstract
Neurodegenerative diseases are a spectrum of chronic, debilitating disorders characterised by the progressive degeneration and death of neurons. Mitochondrial dysfunction has been implicated in most neurodegenerative diseases, but in many instances it is unclear whether such dysfunction is a cause or an effect of the underlying pathology, and whether it represents a viable therapeutic target. It is therefore imperative to utilise and optimise cellular models and experimental techniques appropriate to determine the contribution of mitochondrial dysfunction to neurodegenerative disease phenotypes. In this consensus article, we collate details on and discuss pitfalls of existing experimental approaches to assess mitochondrial function in in vitro cellular models of neurodegenerative diseases, including specific protocols for the measurement of oxygen consumption rate in primary neuron cultures, and single-neuron, time-lapse fluorescence imaging of the mitochondrial membrane potential and mitochondrial NAD(P)H. As part of the Cellular Bioenergetics of Neurodegenerative Diseases (CeBioND) consortium (www.cebiond.org), we are performing cross-disease analyses to identify common and distinct molecular mechanisms involved in mitochondrial bioenergetic dysfunction in cellular models of Alzheimer’s, Parkinson’s, and Huntington’s diseases. Here we provide detailed guidelines and protocols as standardised across the five collaborating laboratories of the CeBioND consortium, with additional contributions from other experts in the field.
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96
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Burke PJ. Mitochondria, Bioenergetics and Apoptosis in Cancer. Trends Cancer 2017; 3:857-870. [PMID: 29198441 PMCID: PMC5957506 DOI: 10.1016/j.trecan.2017.10.006] [Citation(s) in RCA: 269] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 10/12/2017] [Accepted: 10/19/2017] [Indexed: 10/18/2022]
Abstract
Until recently, the dual roles of mitochondria in ATP production (bioenergetics) and apoptosis (cell life/death decision) were thought to be separate. New evidence points to a more intimate link between these two functions, mediated by the remodeling of the mitochondrial ultrastructure during apoptosis. While most of the key molecular players that regulate this process have been identified (primarily membrane proteins), the exact mechanisms by which they function are not yet understood. Because resistance to apoptosis is a hallmark of cancer, and because ultimately all chemotherapies are believed to result directly or indirectly in induction of apoptosis, a better understanding of the biophysical processes involved may lead to new avenues for therapy.
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Affiliation(s)
- Peter J Burke
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, USA; Department of Chemical Engineering and Materials Science, University of California, Irvine, Irvine, CA, USA; Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA.
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97
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Matsushita-Morita M, Tada S, Suzuki S, Hattori R, Kusumoto KI. Enzymatic characterization of a novel Xaa-Pro aminopeptidase XpmA from Aspergillus oryzae expressed in Escherichia coli. J Biosci Bioeng 2017; 124:534-541. [DOI: 10.1016/j.jbiosc.2017.06.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 06/08/2017] [Accepted: 06/18/2017] [Indexed: 01/08/2023]
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98
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Oliva C, Sánchez-Murcia PA, Rico E, Bravo A, Menéndez M, Gago F, Jiménez-Ruiz A. Structure-based domain assignment in Leishmania infantum EndoG: characterization of a pH-dependent regulatory switch and a C-terminal extension that largely dictates DNA substrate preferences. Nucleic Acids Res 2017; 45:9030-9045. [PMID: 28911117 PMCID: PMC5587815 DOI: 10.1093/nar/gkx629] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 07/11/2017] [Indexed: 11/28/2022] Open
Abstract
Mitochondrial endonuclease G from Leishmania infantum (LiEndoG) participates in the degradation of double-stranded DNA (dsDNA) during parasite cell death and is catalytically inactive at a pH of 8.0 or above. The presence, in the primary sequence, of an acidic amino acid-rich insertion exclusive to trypanosomatids and its spatial position in a homology-built model of LiEndoG led us to postulate that this peptide stretch might act as a pH sensor for self-inhibition. We found that a LiEndoG variant lacking residues 145–180 is indeed far more active than its wild-type counterpart at pH values >7.0. In addition, we discovered that (i) LiEndoG exists as a homodimer, (ii) replacement of Ser211 in the active-site SRGH motif with the canonical aspartate from the DRGH motif of other nucleases leads to a catalytically deficient enzyme, (iii) the activity of the S211D variant can be restored upon the concomitant replacement of Ala247 with Arg and (iv) a C-terminal extension is responsible for the observed preferential cleavage of single-stranded DNA (ssDNA) and ssDNA–dsDNA junctions. Taken together, our results support the view that LiEndoG is a multidomain molecular machine whose nuclease activity can be subtly modulated or even abrogated through architectural changes brought about by environmental conditions and interaction with other binding partners.
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MESH Headings
- Amino Acid Sequence
- Amino Acid Substitution
- Catalytic Domain
- Cloning, Molecular
- DNA Cleavage
- DNA, Protozoan/chemistry
- DNA, Protozoan/genetics
- DNA, Protozoan/metabolism
- DNA, Single-Stranded/chemistry
- DNA, Single-Stranded/genetics
- DNA, Single-Stranded/metabolism
- Endodeoxyribonucleases/chemistry
- Endodeoxyribonucleases/genetics
- Endodeoxyribonucleases/metabolism
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Gene Expression
- Hydrogen-Ion Concentration
- Kinetics
- Leishmania infantum/chemistry
- Leishmania infantum/enzymology
- Models, Molecular
- Nucleic Acid Conformation
- Protein Binding
- Protein Conformation, alpha-Helical
- Protein Conformation, beta-Strand
- Protein Interaction Domains and Motifs
- Protein Multimerization
- Protozoan Proteins/chemistry
- Protozoan Proteins/genetics
- Protozoan Proteins/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Sequence Alignment
- Sequence Deletion
- Sequence Homology, Amino Acid
- Structure-Activity Relationship
- Substrate Specificity
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Affiliation(s)
- Cristina Oliva
- Departamento de Biología de Sistemas, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain
| | - Pedro A. Sánchez-Murcia
- Departamento de Ciencias Biomédicas y “Unidad Asociada IQM-CSIC”, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain
| | - Eva Rico
- Departamento de Biología de Sistemas, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain
| | - Ana Bravo
- Departamento de Ciencias Biomédicas y “Unidad Asociada IQM-CSIC”, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain
| | - Margarita Menéndez
- Instituto de Química Física Rocasolano, Consejo Superior de Investigaciones Científicas (CSIC), E-28006 Madrid, Spain
| | - Federico Gago
- Departamento de Ciencias Biomédicas y “Unidad Asociada IQM-CSIC”, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain
- To whom correspondence should be addressed. Tel: +34 918 855 109; Fax: +34 918 854 585; . Correspondence may also be addressed to Federico Gago. Tel: +34 918 854 514; Fax: +34 918 854 591;
| | - Antonio Jiménez-Ruiz
- Departamento de Biología de Sistemas, Universidad de Alcalá, E-28805 Alcalá de Henares, Madrid, Spain
- To whom correspondence should be addressed. Tel: +34 918 855 109; Fax: +34 918 854 585; . Correspondence may also be addressed to Federico Gago. Tel: +34 918 854 514; Fax: +34 918 854 591;
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99
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Schaefer PM, Hilpert D, Niederschweiberer M, Neuhauser L, Kalinina S, Calzia E, Rueck A, von Einem B, von Arnim CAF. Mitochondrial matrix pH as a decisive factor in neurometabolic imaging. NEUROPHOTONICS 2017; 4:045004. [PMID: 29181426 PMCID: PMC5685807 DOI: 10.1117/1.nph.4.4.045004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 10/16/2017] [Indexed: 06/07/2023]
Abstract
Alterations of cellular bioenergetics are a common feature in most neurodegenerative disorders. However, there is a selective vulnerability of different brain regions, cell types, and even mitochondrial populations to these metabolic disturbances. Thus, the aim of our study was to establish and validate an in vivo metabolic imaging technique to screen for mitochondrial function on the subcellular level. Based on nicotinamide adenine dinucleotide (phosphate) fluorescence lifetime imaging microscopy [NAD(P)H FLIM], we performed a quantitative correlation to high-resolution respirometry. Thereby, we revealed mitochondrial matrix pH as a decisive factor in imaging NAD(P)H redox state. By combining both parameters, we illustrate a quantitative, high-resolution assessment of mitochondrial function in metabolically modified cells as well as in an amyloid precursor protein-overexpressing model of Alzheimer's disease. Our metabolic imaging technique provides the basis for dissecting mitochondrial deficits not only in a range of neurodegenerative diseases, shedding light onto bioenergetic failures of cells remaining in their metabolic microenvironment.
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Affiliation(s)
| | - Diana Hilpert
- Ulm University, Department of Neurology, Ulm, Germany
| | | | | | - Sviatlana Kalinina
- Ulm University, Core Facility Confocal and Multiphoton Microscopy, Ulm, Germany
| | - Enrico Calzia
- University Medical School, Institute of Anesthesiological Pathophysiology and Process Engineering, Ulm, Germany
| | - Angelika Rueck
- Ulm University, Core Facility Confocal and Multiphoton Microscopy, Ulm, Germany
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100
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Rebuffet E, Frick A, Järvå M, Törnroth-Horsefield S. Cell-free production and characterisation of human uncoupling protein 1-3. Biochem Biophys Rep 2017; 10:276-281. [PMID: 28955755 PMCID: PMC5614671 DOI: 10.1016/j.bbrep.2017.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 04/04/2017] [Accepted: 04/07/2017] [Indexed: 11/22/2022] Open
Abstract
The uncoupling proteins (UCPs) leak protons across the inner mitochondrial membrane, thus uncoupling the proton gradient from ATP synthesis. The main known physiological role for this is heat generation by UCP1 in brown adipose tissue. However, UCPs are also believed to be important for protection against reactive oxygen species, fine-tuning of metabolism and have been suggested to be involved in disease states such as obesity, diabetes and cancer. Structural studies of UCPs have long been hampered by difficulties in sample preparation with neither expression in yeast nor refolding from inclusion bodies in E. coli yielding sufficient amounts of pure and stable protein. In this study, we have developed a protocol for cell-free expression of human UCP1, 2 and 3, resulting in 1 mg pure protein per 20 mL of expression media. Lauric acid, a natural UCP ligand, significantly improved protein thermal stability and was therefore added during purification. Secondary structure characterisation using circular dichroism spectroscopy revealed the proteins to consist of mostly α-helices, as expected. All three UCPs were able to bind GDP, a well-known physiological inhibitor, as shown by the Fluorescence Resonance Energy Transfer (FRET) technique, suggesting that the proteins are in a natively folded state. A protocol for cell-free expression of human uncoupling protein 1–3 is described. Addition of native membrane components increased expression levels. Addition of lauric acid increased protein stability in solution. CD spectroscopy confirms alpha-helical secondary structure as expected. All proteins binds GDP as demonstrated by Fluorescence Resonance Energy Transfer.
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Affiliation(s)
- Etienne Rebuffet
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE-405 30 Gothenburg, Sweden
| | - Anna Frick
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE-405 30 Gothenburg, Sweden
| | - Michael Järvå
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE-405 30 Gothenburg, Sweden
| | - Susanna Törnroth-Horsefield
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE-405 30 Gothenburg, Sweden.,Department of Biochemistry and Structural Biology, Centre for Molecular Protein Science, Lund University, Box 124, 221 00 Lund, Sweden
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