1
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Serano M, Pietrangelo L, Paolini C, Guarnier FA, Protasi F. Oxygen Consumption and Basal Metabolic Rate as Markers of Susceptibility to Malignant Hyperthermia and Heat Stroke. Cells 2022; 11:2468. [PMID: 36010545 PMCID: PMC9406760 DOI: 10.3390/cells11162468] [Citation(s) in RCA: 1] [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: 07/05/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 12/28/2022] Open
Abstract
Calsequestrin 1 (CASQ1) and Ryanodine receptor 1 (RYR1) are two of the main players in excitation-contraction (EC) coupling. CASQ1-knockout mice and mice carrying a mutation in RYR1 (Y522S) linked to human malignant hyperthermia susceptibility (MHS) both suffer lethal hypermetabolic episodes when exposed to halothane (MHS crises) and to environmental heat (heat stroke, HS). The phenotype of Y522S is more severe than that of CASQ1-null mice. As MHS and HS are hypermetabolic responses, we studied the metabolism of adult CASQ1-null and Y522S mice using wild-type (WT) mice as controls. We found that CASQ1-null and Y522S mice have increased food consumption and higher core temperature at rest. By indirect calorimetry, we then verified that CASQ1-null and Y522S mice show an increased oxygen consumption and a lower respiratory quotient (RQ). The accelerated metabolism of CASQ1-null and Y522S mice was also accompanied with a reduction in body fat. Moreover, both mouse models displayed increased oxygen consumption and a higher core temperature during heat stress. The results collected suggest that metabolic rate, oxygen consumption, and body temperature at rest, all more elevated in Y522S than in CASQ1-null mice, could possibly be used as predictors of the level of susceptibility to hyperthermic crises of mice (and possibly humans).
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Affiliation(s)
- Matteo Serano
- CAST, Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
- DMSI, Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
| | - Laura Pietrangelo
- CAST, Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
- DMSI, Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
| | - Cecilia Paolini
- CAST, Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
- DNICS, Department of Neuroscience and Clinical Sciences, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
| | - Flavia A. Guarnier
- Department of General Pathology, Londrina State University, Londrina 86057-970, Brazil
| | - Feliciano Protasi
- CAST, Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
- DMSI, Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy
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2
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On the Mechanism of Cardioprotective Effect of Fabomotizole in Alcoholic Cardiomyopathy. Bull Exp Biol Med 2021; 171:41-44. [PMID: 34050832 DOI: 10.1007/s10517-021-05168-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Indexed: 10/21/2022]
Abstract
The molecular mechanisms underlying the cardioprotective effect of fabomotizole were studied using the translational rat model of alcoholic cardiomyopathy developed by us. It was shown that intraperitoneal administration of fabomotizole (15 mg/kg) for 28 days to animals with alcoholic cardiomyopathy contributes to normalization of the expression of mRNA of genes of regulatory proteins СаМ (p=0.00001), Ерас1 (p=0.021), and Ерас2 (p=0.018) and receptors RyR2 (p=0.0031) and IP3R2 (p=0.006) in the myocardium of the myocardium of the left ventricle that is enhanced in control animals (p<0.05). These changes were accompanied by echocardiographically documented decrease in the degree of left ventricle remodeling and improvement of its inotropic function.
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3
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Zemljic-Harpf AE, Hoe LES, Schilling JM, Zuniga-Hertz JP, Nguyen A, Vaishnav YJ, Belza GJ, Budiono BP, Patel PM, Head BP, Dillmann WH, Mahata SK, Peart JN, Roth DM, Headrick JP, Patel HH. Morphine induces physiological, structural, and molecular benefits in the diabetic myocardium. FASEB J 2021; 35:e21407. [PMID: 33583084 PMCID: PMC10843897 DOI: 10.1096/fj.201903233r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/12/2021] [Accepted: 01/19/2021] [Indexed: 01/03/2023]
Abstract
The obesity epidemic has increased type II diabetes mellitus (T2DM) across developed countries. Cardiac T2DM risks include ischemic heart disease, heart failure with preserved ejection fraction, intolerance to ischemia-reperfusion (I-R) injury, and refractoriness to cardioprotection. While opioids are cardioprotective, T2DM causes opioid receptor signaling dysfunction. We tested the hypothesis that sustained opioid receptor stimulus may overcome diabetes mellitus-induced cardiac dysfunction via membrane/mitochondrial-dependent protection. In a murine T2DM model, we investigated effects of morphine on cardiac function, I-R tolerance, ultrastructure, subcellular cholesterol expression, mitochondrial protein abundance, and mitochondrial function. T2DM induced 25% weight gain, hyperglycemia, glucose intolerance, cardiac hypertrophy, moderate cardiac depression, exaggerated postischemic myocardial dysfunction, abnormalities in mitochondrial respiration, ultrastructure and Ca2+ -induced swelling, and cell death were all evident. Morphine administration for 5 days: (1) improved glucose homeostasis; (2) reversed cardiac depression; (3) enhanced I-R tolerance; (4) restored mitochondrial ultrastructure; (5) improved mitochondrial function; (6) upregulated Stat3 protein; and (7) preserved membrane cholesterol homeostasis. These data show that morphine treatment restores contractile function, ischemic tolerance, mitochondrial structure and function, and membrane dynamics in type II diabetic hearts. These findings suggest potential translational value for short-term, but high-dose morphine administration in diabetic patients undergoing or recovering from acute ischemic cardiovascular events.
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Affiliation(s)
- Alice E. Zemljic-Harpf
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Louise E. See Hoe
- Department of Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, QLD, Australia
| | - Jan M. Schilling
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Juan P. Zuniga-Hertz
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Alexander Nguyen
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Yash J. Vaishnav
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Gianna J. Belza
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Boris P. Budiono
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, QLD, Australia
| | - Piyush M. Patel
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Brian P. Head
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Wolfgang H. Dillmann
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Sushil K. Mahata
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jason N. Peart
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, QLD, Australia
| | - David M. Roth
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - John P. Headrick
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, QLD, Australia
| | - Hemal H. Patel
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
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4
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Gagnon KB, Delpire E. Sodium Transporters in Human Health and Disease. Front Physiol 2021; 11:588664. [PMID: 33716756 PMCID: PMC7947867 DOI: 10.3389/fphys.2020.588664] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 10/06/2020] [Indexed: 12/12/2022] Open
Abstract
Sodium (Na+) electrochemical gradients established by Na+/K+ ATPase activity drives the transport of ions, minerals, and sugars in both excitable and non-excitable cells. Na+-dependent transporters can move these solutes in the same direction (cotransport) or in opposite directions (exchanger) across both the apical and basolateral plasma membranes of polarized epithelia. In addition to maintaining physiological homeostasis of these solutes, increases and decreases in sodium may also initiate, directly or indirectly, signaling cascades that regulate a variety of intracellular post-translational events. In this review, we will describe how the Na+/K+ ATPase maintains a Na+ gradient utilized by multiple sodium-dependent transport mechanisms to regulate glucose uptake, excitatory neurotransmitters, calcium signaling, acid-base balance, salt-wasting disorders, fluid volume, and magnesium transport. We will discuss how several Na+-dependent cotransporters and Na+-dependent exchangers have significant roles in human health and disease. Finally, we will discuss how each of these Na+-dependent transport mechanisms have either been shown or have the potential to use Na+ in a secondary role as a signaling molecule.
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Affiliation(s)
- Kenneth B. Gagnon
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, United States
| | - Eric Delpire
- Department of Anesthesiology, School of Medicine, Vanderbilt University, Nashville, TN, United States
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Purslow PP, Gagaoua M, Warner RD. Insights on meat quality from combining traditional studies and proteomics. Meat Sci 2020; 174:108423. [PMID: 33422773 DOI: 10.1016/j.meatsci.2020.108423] [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: 10/29/2020] [Revised: 12/23/2020] [Accepted: 12/28/2020] [Indexed: 12/16/2022]
Abstract
Following a century of major discoveries on the mechanisms determining meat colour and tenderness using traditional scientific methods, further research into complex and interactive factors contributing to variations in meat quality is increasingly being based on data-driven "omics" approaches such as proteomics. Using two recent meta-analyses of proteomics studies on beef colour and tenderness, this review examines how knowledge of the mechanisms and factors underlying variations in these meat qualities can be both confirmed and extended by data-driven approaches. While proteomics seems to overlook some sources of variations in beef toughness, it highlights the role of post-mortem energy metabolism in setting the conditions for development of meat colour and tenderness, and also points to the complex interplay of energy metabolism, calcium regulation and mitochondrial metabolism. In using proteomics as a future tool for explaining variations in meat quality, the need for confirmation by further hypothesis-driven experimental studies of post-hoc explanations of why certain proteins are biomarkers of beef quality in data-driven studies is emphasised.
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Affiliation(s)
- Peter P Purslow
- Tandil Centre for Veterinary Investigation (CIVETAN), National University of Central Buenos Aires Province, Tandil B7001BBO, Argentina; School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, Melbourne University, Parkville 3010, Australia.
| | - Mohammed Gagaoua
- Food Quality and Sensory Science Department, Teagasc Ashtown Food Research Centre, Ashtown, Dublin 15, Ireland
| | - Robyn D Warner
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, Melbourne University, Parkville 3010, Australia
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6
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Shah SI, Ullah G. The Function of Mitochondrial Calcium Uniporter at the Whole-Cell and Single Mitochondrion Levels in WT, MICU1 KO, and MICU2 KO Cells. Cells 2020; 9:E1520. [PMID: 32580385 PMCID: PMC7349584 DOI: 10.3390/cells9061520] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 01/05/2023] Open
Abstract
Mitochondrial Ca2+ ([Ca2+]M) uptake through its Ca2+ uniporter (MCU) is central to many cell functions such as bioenergetics, spatiotemporal organization of Ca2+ signals, and apoptosis. MCU activity is regulated by several intrinsic proteins including MICU1, MICU2, and EMRE. While significant details about the role of MICU1, MICU2, and EMRE in MCU function have emerged recently, a key challenge for the future experiments is to investigate how these regulatory proteins modulate mitochondrial Ca2+ influx through MCU in intact cells under pathophysiological conditions. This is further complicated by the fact that several variables affecting MCU function change dynamically as cell functions. To overcome this void, we develop a data-driven model that closely replicates the behavior of MCU under a wide range of cytosolic Ca2+ ([Ca2+]C), [Ca2+]M, and mitochondrial membrane potential values in WT, MICU1 knockout (KO), and MICU2 KO cells at the single mitochondrion and whole-cell levels. The model is extended to investigate how MICU1 or MICU2 KO affect mitochondrial function. Moreover, we show how Ca2+ buffering proteins, the separation between mitochondrion and Ca2+-releasing stores, and the duration of opening of Ca2+-releasing channels affect mitochondrial function under different conditions. Finally, we demonstrate an easy extension of the model to single channel function of MCU.
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Affiliation(s)
| | - Ghanim Ullah
- Department of Physics, University of South Florida, Tampa, FL 33647, USA;
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7
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Gökerküçük EB, Tramier M, Bertolin G. Imaging Mitochondrial Functions: from Fluorescent Dyes to Genetically-Encoded Sensors. Genes (Basel) 2020; 11:genes11020125. [PMID: 31979408 PMCID: PMC7073610 DOI: 10.3390/genes11020125] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 12/18/2022] Open
Abstract
Mitochondria are multifunctional organelles that are crucial to cell homeostasis. They constitute the major site of energy production for the cell, they are key players in signalling pathways using secondary messengers such as calcium, and they are involved in cell death and redox balance paradigms. Mitochondria quickly adapt their dynamics and biogenesis rates to meet the varying energy demands of the cells, both in normal and in pathological conditions. Therefore, understanding simultaneous changes in mitochondrial functions is crucial in developing mitochondria-based therapy options for complex pathological conditions such as cancer, neurological disorders, and metabolic syndromes. To this end, fluorescence microscopy coupled to live imaging represents a promising strategy to track these changes in real time. In this review, we will first describe the commonly available tools to follow three key mitochondrial functions using fluorescence microscopy: Calcium signalling, mitochondrial dynamics, and mitophagy. Then, we will focus on how the development of genetically-encoded fluorescent sensors became a milestone for the understanding of these mitochondrial functions. In particular, we will show how these tools allowed researchers to address several biochemical activities in living cells, and with high spatiotemporal resolution. With the ultimate goal of tracking multiple mitochondrial functions simultaneously, we will conclude by presenting future perspectives for the development of novel genetically-encoded fluorescent biosensors.
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8
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Pérez-Valencia JA, Prosdocimi F, Cesari IM, da Costa IR, Furtado C, Agostini M, Rumjanek FD. Angiogenesis and evading immune destruction are the main related transcriptomic characteristics to the invasive process of oral tongue cancer. Sci Rep 2018; 8:2007. [PMID: 29386520 PMCID: PMC5792437 DOI: 10.1038/s41598-017-19010-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/19/2017] [Indexed: 01/29/2023] Open
Abstract
Metastasis of head and neck tumors is responsible for a high mortality rate. Understanding its biochemistry may allow insights into tumorigenesis. To that end we carried out RNA-Seq analyses of 5 SCC9 derived oral cancer cell lines displaying increased invasive potential. Differentially expressed genes (DEGs) were annotated based on p-values and false discovery rate (q-values). All 292 KEGG pathways related to the human genome were compared in order to pinpoint the absolute and relative contributions to the invasive process considering the 8 hallmarks of cancer plus 2 new defined categories, as well as we made with our transcriptomic data. In terms of absolute contribution, the highest correlations were associated to the categories of evading immune destruction and energy metabolism and for relative contributions, angiogenesis and evading immune destruction. DEGs were distributed into each one of all possible modes of regulation, regarding up, down and continuum expression, along the 3 stages of metastatic progression. For p-values twenty-six genes were consistently present along the tumoral progression and 4 for q-values. Among the DEGs, we found 2 novel potentially informative metastatic markers: PIGG and SLC8B1. Furthermore, interactome analysis showed that MYH14, ANGPTL4, PPARD and ENPP1 are amenable to pharmacological interventions.
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Affiliation(s)
- Juan Alberto Pérez-Valencia
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Francisco Prosdocimi
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Italo M Cesari
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Igor Rodrigues da Costa
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | - Michelle Agostini
- Departamento de Patologia e Diagnóstico Oral, Faculdade de Odontologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Franklin David Rumjanek
- Instituto de Bioquímica Médica Leopoldo de Meis, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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9
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The study of protein biomarkers to understand the biochemical processes underlying beef color development in young bulls. Meat Sci 2017; 134:18-27. [DOI: 10.1016/j.meatsci.2017.07.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 07/06/2017] [Accepted: 07/17/2017] [Indexed: 01/05/2023]
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10
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Logan A, Murphy MP. Using chemical biology to assess and modulate mitochondria: progress and challenges. Interface Focus 2017; 7:20160151. [PMID: 28382206 PMCID: PMC5311910 DOI: 10.1098/rsfs.2016.0151] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Our understanding of the role of mitochondria in biomedical sciences has expanded considerably over the past decade. In addition to their well-known metabolic roles, mitochondrial are also central to signalling for various processes through the generation of signals such as ROS and metabolites that affect cellular homeostasis, as well as other processes such as cell death and inflammation. Thus, mitochondrial function and dysfunction are central to the health and fate of the cell. Consequently, there is considerable interest in better understanding and assessing the many roles of mitochondria. Furthermore, there is also a growing realization that mitochondrial are a promising drug target in a wide range of pathologies. The application of interdisciplinary approaches at the interface between chemistry and biology are opening up new opportunities to understand mitochondrial function and in assessing the role of the organelle in biology. This work and the experience thus gained are leading to the development of new classes of therapies. Here, we overview the progress that has been made to date on exploring the chemical biology of the organelle and then focus on future challenges and opportunities that face this rapidly developing field.
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Affiliation(s)
- Angela Logan
- MRC Mitochondrial Biology Unit , Hills Road, Cambridge CB2 0XY , UK
| | - Michael P Murphy
- MRC Mitochondrial Biology Unit , Hills Road, Cambridge CB2 0XY , UK
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11
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Requejo-Aguilar R, Bolaños JP. Mitochondrial control of cell bioenergetics in Parkinson's disease. Free Radic Biol Med 2016; 100:123-137. [PMID: 27091692 PMCID: PMC5065935 DOI: 10.1016/j.freeradbiomed.2016.04.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/13/2016] [Accepted: 04/14/2016] [Indexed: 12/15/2022]
Abstract
Parkinson disease (PD) is a neurodegenerative disorder characterized by a selective loss of dopaminergic neurons in the substantia nigra. The earliest biochemical signs of the disease involve failure in mitochondrial-endoplasmic reticulum cross talk and lysosomal function, mitochondrial electron chain impairment, mitochondrial dynamics alterations, and calcium and iron homeostasis abnormalities. These changes are associated with increased mitochondrial reactive oxygen species (mROS) and energy deficiency. Recently, it has been reported that, as an attempt to compensate for the mitochondrial dysfunction, neurons invoke glycolysis as a low-efficient mode of energy production in models of PD. Here, we review how mitochondria orchestrate the maintenance of cellular energetic status in PD, with special focus on the switch from oxidative phosphorylation to glycolysis, as well as the implication of endoplasmic reticulum and lysosomes in the control of bioenergetics.
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Affiliation(s)
- Raquel Requejo-Aguilar
- Department of Biochemistry and Molecular Biology, University of Cordoba, Institute Maimonides of Biomedical Investigation of Cordoba (IMIBIC), Cordoba, Spain
| | - Juan P Bolaños
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca-CSIC, Zacarias Gonzalez, 2, 37007 Salamanca, Spain.
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12
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Kudelko M, Chan CWL, Sharma R, Yao Q, Lau E, Chu IK, Cheah KSE, Tanner JA, Chan D. Label-Free Quantitative Proteomics Reveals Survival Mechanisms Developed by Hypertrophic Chondrocytes under ER Stress. J Proteome Res 2015; 15:86-99. [DOI: 10.1021/acs.jproteome.5b00537] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
| | | | - Rakesh Sharma
- Department
of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, China
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13
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Mironova GD, Saris NEL, Belosludtseva NV, Agafonov AV, Elantsev AB, Belosludtsev KN. Involvement of palmitate/Ca2+(Sr2+)-induced pore in the cycling of ions across the mitochondrial membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:488-95. [PMID: 25450352 DOI: 10.1016/j.bbamem.2014.10.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 09/23/2014] [Accepted: 10/20/2014] [Indexed: 10/24/2022]
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14
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Docampo R, Vercesi AE, Huang G. Mitochondrial calcium transport in trypanosomes. Mol Biochem Parasitol 2014; 196:108-16. [PMID: 25218432 DOI: 10.1016/j.molbiopara.2014.09.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 08/22/2014] [Accepted: 09/02/2014] [Indexed: 01/26/2023]
Abstract
The biochemical peculiarities of trypanosomes were fundamental for the recent molecular identification of the long-sought channel involved in mitochondrial Ca(2+) uptake, the mitochondrial Ca(2+) uniporter or MCU. This discovery led to the finding of numerous regulators of the channel, which form a high molecular weight complex with MCU. Some of these regulators have been bioinformatically identified in trypanosomes, which are the first eukaryotic organisms described for which MCU is essential. In trypanosomes MCU is important for buffering cytosolic Ca(2+) changes and for activation of the bioenergetics of the cells. Future work on this pathway in trypanosomes promises further insight into the biology of these fascinating eukaryotes, as well as the potential for novel target discovery.
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Affiliation(s)
- Roberto Docampo
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA; Departamento de Patologia Clínica, State University of Campinas, Campinas 13083, SP, Brazil.
| | - Anibal E Vercesi
- Departamento de Patologia Clínica, State University of Campinas, Campinas 13083, SP, Brazil
| | - Guozhong Huang
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
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15
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Morató L, Bertini E, Verrigni D, Ardissone A, Ruiz M, Ferrer I, Uziel G, Pujol A. Mitochondrial dysfunction in central nervous system white matter disorders. Glia 2014; 62:1878-94. [DOI: 10.1002/glia.22670] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 03/20/2014] [Accepted: 03/21/2014] [Indexed: 12/26/2022]
Affiliation(s)
- Laia Morató
- Neurometabolic Diseases Laboratory; Bellvitge Biomedical Research Institute (IDIBELL); L'Hospitalet de Llobregat Barcelona Spain
- Center for Biomedical Research on Rare Diseases (CIBERER); ISCIII Spain
| | - Enrico Bertini
- Unit for Neuromuscular and Neurodegenerative Diseases, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital; IRCCS Rome Italy
| | - Daniela Verrigni
- Unit for Neuromuscular and Neurodegenerative Diseases, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital; IRCCS Rome Italy
| | - Anna Ardissone
- Department of Child Neurology The Foundation “Carlo Besta” Neurological Institute (IRCCS); Milan Italy
| | - Montse Ruiz
- Neurometabolic Diseases Laboratory; Bellvitge Biomedical Research Institute (IDIBELL); L'Hospitalet de Llobregat Barcelona Spain
- Center for Biomedical Research on Rare Diseases (CIBERER); ISCIII Spain
| | - Isidre Ferrer
- Institute of Neuropathology, University of Barcelona, L'Hospitalet de Llobregat; Barcelona Spain
- Center for Biomedical Research on Neurodegenerative Diseases (CIBERNED); ISCIII Spain
| | - Graziella Uziel
- Department of Child Neurology The Foundation “Carlo Besta” Neurological Institute (IRCCS); Milan Italy
| | - Aurora Pujol
- Neurometabolic Diseases Laboratory; Bellvitge Biomedical Research Institute (IDIBELL); L'Hospitalet de Llobregat Barcelona Spain
- Center for Biomedical Research on Rare Diseases (CIBERER); ISCIII Spain
- Catalan Institution of Research and Advanced Studies (ICREA); Barcelona Spain
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16
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Markham A, Bains R, Franklin P, Spedding M. Changes in mitochondrial function are pivotal in neurodegenerative and psychiatric disorders: how important is BDNF? Br J Pharmacol 2014; 171:2206-29. [PMID: 24720259 PMCID: PMC3976631 DOI: 10.1111/bph.12531] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 11/08/2013] [Accepted: 11/11/2013] [Indexed: 12/13/2022] Open
Abstract
The brain is at the very limit of its energy supply and has evolved specific means of adapting function to energy supply, of which mitochondria form a crucial link. Neurotrophic and inflammatory processes may not only have opposite effects on neuroplasticity, but also involve opposite effects on mitochondrial oxidative phosphorylation and glycolytic processes, respectively, modulated by stress and glucocorticoids, which also have marked effects on mood. Neurodegenerative processes show marked disorders in oxidative metabolism in key brain areas, sometimes decades before symptoms appear (Parkinson's and Alzheimer's diseases). We argue that brain-derived neurotrophic factor couples activity to changes in respiratory efficiency and these effects may be opposed by inflammatory cytokines, a key factor in neurodegenerative processes.
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Affiliation(s)
- A Markham
- Department of Pharmacy, Health & Well Being, Faculty of Applied Sciences, University of SunderlandSunderland, UK
| | - R Bains
- University of PortsmouthPortsmouth, UK
| | - P Franklin
- Department of Pharmacy, Health & Well Being, Faculty of Applied Sciences, University of SunderlandSunderland, UK
| | - M Spedding
- Spedding Research Solutions SARLLe Vesinet, France
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17
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Khananshvili D. The SLC8 gene family of sodium-calcium exchangers (NCX) - structure, function, and regulation in health and disease. Mol Aspects Med 2013; 34:220-35. [PMID: 23506867 DOI: 10.1016/j.mam.2012.07.003] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2011] [Accepted: 03/08/2012] [Indexed: 01/12/2023]
Abstract
The SLC8 gene family encoding Na(+)/Ca(2+) exchangers (NCX) belongs to the CaCA (Ca(2+)/Cation Antiporter) superfamily. Three mammalian genes (SLC8A1, SLC8A2, and SLC8A3) and their splice variants are expressed in a tissue-specific manner to mediate Ca(2+)-fluxes across the cell-membrane and thus, significantly contribute to regulation of Ca(2+)-dependent events in many cell types. A long-wanted mitochondrial Na(+)/Ca(2+) exchanger has been recently identified as NCLX protein, representing a gene product of SLC8B1. Distinct NCX isoform/splice variants contribute to excitation-contraction coupling, long-term potentiation of the brain and learning, blood pressure regulation, immune response, neurotransmitter and insulin secretion, mitochondrial bioenergetics, etc. Altered expression and regulation of NCX proteins contribute to distorted Ca(2+)-homeostasis in heart failure, arrhythmia, cerebral ischemia, hypertension, diabetes, renal Ca(2+) reabsorption, muscle dystrophy, etc. Recently, high-resolution X-ray structures of Ca(2+)-binding regulatory domains of eukaryotic NCX and of full-size prokaryotic NCX have become available and the dynamic properties have been analyzed by advanced biophysical approaches. Molecular silencing/overexpression of NCX in cellular systems and organ-specific KO mouse models provided useful information on the contribution of distinct NCX variants to cellular and systemic functions under various pathophysiological conditions. Selective inhibition or activation of predefined NCX variants in specific diseases might have clinical relevance, although this breakthrough has not yet been realized. A better understanding of the underlying molecular mechanisms as well as the development of in vitro procedures for high-throughput screening of "drug-like" compounds may lead to selective pharmacological targeting of NCX variants.
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Affiliation(s)
- Daniel Khananshvili
- Department of Physiology and Pharmacology, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv, Tel-Aviv 69978, Israel.
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18
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Calì T, Ottolini D, Brini M. Calcium and Endoplasmic Reticulum-Mitochondria Tethering in Neurodegeneration. DNA Cell Biol 2013; 32:140-6. [DOI: 10.1089/dna.2013.2011] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Tito Calì
- Department of Comparative Biomedicine and Food Science, University of Padova, Padova, Italy
| | - Denis Ottolini
- Department of Comparative Biomedicine and Food Science, University of Padova, Padova, Italy
| | - Marisa Brini
- Department of Comparative Biomedicine and Food Science, University of Padova, Padova, Italy
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19
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Gellerich FN, Gizatullina Z, Gainutdinov T, Muth K, Seppet E, Orynbayeva Z, Vielhaber S. The control of brain mitochondrial energization by cytosolic calcium: the mitochondrial gas pedal. IUBMB Life 2013; 65:180-90. [PMID: 23401251 DOI: 10.1002/iub.1131] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 12/08/2012] [Indexed: 11/05/2022]
Abstract
This review focuses on problems of the intracellular regulation of mitochondrial function in the brain via the (i) supply of mitochondria with ADP by means of ADP shuttles and channels and (ii) the Ca(2+) control of mitochondrial substrate supply. The permeability of the mitochondrial outer membrane for adenine nucleotides is low. Therefore rate dependent concentration gradients exist between the mitochondrial intermembrane space and the cytosol. The existence of dynamic ADP gradients is an important precondition for the functioning of ADP shuttles, for example CrP-shuttle. Cr at mM concentrations instead of ADP diffuses from the cytosol through the porin pores into the intermembrane space. The CrP-shuttle isoenzymes work in different directions which requires different metabolite concentrations mainly caused by dynamic ADP compartmentation. The ADP shuttle mechanisms alone cannot explain the load dependent changes in mitochondrial energization, and a complete model of mitochondrial regulation have to account the Ca(2+) -dependent substrate supply too. According to the old paradigmatic view, Ca(2+) (cyt) taken up by the mitochondrial Ca(2+) uniporter activates dehydrogenases within the matrix. However, recently it was found that Ca(2+) (cyt) at low nM concentrations exclusively activates the state 3 respiration via aralar, the mitochondrial glutamate/aspartate carrier. At higher Ca(2+) (cyt) (> 500 nM), brain mitochondria take up Ca(2+) for activation of substrate oxidation rates. Since brain mitochondrial pyruvate oxidation is only slightly influenced by Ca(2+) (cyt) , it was proposed that the cytosolic formation of pyruvate from its precursors is tightly controlled by the Ca(2+) dependent malate/aspartate shuttle. At low (50-100 nM) Ca(2+) (cyt) the pyruvate formation is suppressed, providing a substrate limitation control in neurons. This so called "gas pedal" mechanism explains why the energy metabolism of neurons in the nucleus suprachiasmaticus could be down-regulated at night but activated at day as a basis for the circadian changes in Ca(2+) (cyt) . It also could explain the energetic disadvantages caused by altered Ca(2+) (cyt) at mitochondrial diseases and neurodegeneration.
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Affiliation(s)
- Frank Norbert Gellerich
- Leibniz Institute for Neurobiology Magdeburg, Department of Behavioral Neurology, 39118 Magdeburg, Germany.
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20
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Abstract
Mitochondrial oxidative phosphorylation (OXPHOS) sustains organelle function and plays a central role in cellular energy metabolism. The OXPHOS system consists of 5 multisubunit complexes (CI-CV) that are built up of 92 different structural proteins encoded by the nuclear (nDNA) and mitochondrial DNA (mtDNA). Biogenesis of a functional OXPHOS system further requires the assistance of nDNA-encoded OXPHOS assembly factors, of which 35 are currently identified. In humans, mutations in both structural and assembly genes and in genes involved in mtDNA maintenance, replication, transcription, and translation induce 'primary' OXPHOS disorders that are associated with neurodegenerative diseases including Leigh syndrome (LS), which is probably the most classical OXPHOS disease during early childhood. Here, we present the current insights regarding function, biogenesis, regulation, and supramolecular architecture of the OXPHOS system, as well as its genetic origin. Next, we provide an inventory of OXPHOS structural and assembly genes which, when mutated, induce human neurodegenerative disorders. Finally, we discuss the consequences of mutations in OXPHOS structural and assembly genes at the single cell level and how this information has advanced our understanding of the role of OXPHOS dysfunction in neurodegeneration.
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21
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Abstract
Mitochondria have various essential functions in metabolism and in determining cell fate during apoptosis. In addition, mitochondria are also important nodes in a number of signaling pathways. For example, mitochondria can modulate signals transmitted by second messengers such as calcium. Because mitochondria are also major sources of reactive oxygen species (ROS), they can contribute to redox signaling--for example, by the production of ROS such as hydrogen peroxide that can reversibly modify cysteine residues and thus the activity of target proteins. Mitochondrial ROS production is thought to play a role in hypoxia signaling by stabilizing the oxygen-sensitive transcription factor hypoxia-inducible factor-1α. New evidence has extended the mechanism of mitochondrial redox signaling in cellular responses to hypoxia in interesting and unexpected ways. Hypoxia altered the microtubule-dependent transport of mitochondria so that the organelles accumulated in the perinuclear region, where they increased the intranuclear concentration of ROS. The increased ROS in turn enhanced the expression of hypoxia-sensitive genes such as VEGF (vascular endothelial growth factor) not by reversibly oxidizing a protein, but by oxidizing DNA sequences in the hypoxia response element of the VEGF promoter. This paper and other recent work suggest a new twist on mitochondrial signaling: that the redistribution of mitochondria within the cell can be a component of regulatory pathways.
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Affiliation(s)
- Michael P Murphy
- Medical Research Council, Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK.
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22
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Calì T, Ottolini D, Brini M. Mitochondrial Ca(2+) and neurodegeneration. Cell Calcium 2012; 52:73-85. [PMID: 22608276 PMCID: PMC3396847 DOI: 10.1016/j.ceca.2012.04.015] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Revised: 04/18/2012] [Accepted: 04/20/2012] [Indexed: 12/16/2022]
Abstract
Mitochondria are essential for ensuring numerous fundamental physiological processes such as cellular energy, redox balance, modulation of Ca2+ signaling and important biosynthetic pathways. They also govern the cell fate by participating in the apoptosis pathway. The mitochondrial shape, volume, number and distribution within the cells are strictly controlled. The regulation of these parameters has an impact on mitochondrial function, especially in the central nervous system, where trafficking of mitochondria is critical to their strategic intracellular distribution, presumably according to local energy demands. Thus, the maintenance of a healthy mitochondrial population is essential to avoid the impairment of the processes they regulate: for this purpose, cells have developed mechanisms involving a complex system of quality control to remove damaged mitochondria, or to renew them. Defects of these processes impair mitochondrial function and lead to disordered cell function, i.e., to a disease condition. Given the standard role of mitochondria in all cells, it might be expected that their dysfunction would give rise to similar defects in all tissues. However, damaged mitochondrial function has pleiotropic effects in multicellular organisms, resulting in diverse pathological conditions, ranging from cardiac and brain ischemia, to skeletal muscle myopathies to neurodegenerative diseases. In this review, we will focus on the relationship between mitochondrial (and cellular) derangements and Ca2+ dysregulation in neurodegenerative diseases, emphasizing the evidence obtained in genetic models. Common patterns, that recognize the derangement of Ca2+ and energy control as a causative factor, have been identified: advances in the understanding of the molecular regulation of Ca2+ homeostasis, and on the ways in which it could become perturbed in neurological disorders, may lead to the development of therapeutic strategies that modulate neuronal Ca2+ signaling.
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Affiliation(s)
- Tito Calì
- Department of Comparative Biomedicine and Food Science, University of Padova, Padova, Italy
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23
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Smith RAJ, Hartley RC, Cochemé HM, Murphy MP. Mitochondrial pharmacology. Trends Pharmacol Sci 2012; 33:341-52. [PMID: 22521106 DOI: 10.1016/j.tips.2012.03.010] [Citation(s) in RCA: 360] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 02/28/2012] [Accepted: 03/13/2012] [Indexed: 12/13/2022]
Abstract
Mitochondria are being recognized as key factors in many unexpected areas of biomedical science. In addition to their well-known roles in oxidative phosphorylation and metabolism, it is now clear that mitochondria are also central to cell death, neoplasia, cell differentiation, the innate immune system, oxygen and hypoxia sensing, and calcium metabolism. Disruption to these processes contributes to a range of human pathologies, making mitochondria a potentially important, but currently seemingly neglected, therapeutic target. Mitochondrial dysfunction is often associated with oxidative damage, calcium dyshomeostasis, defective ATP synthesis, or induction of the permeability transition pore. Consequently, therapies designed to prevent these types of damage are beneficial and can be used to treat many diverse and apparently unrelated indications. Here we outline the biological properties that make mitochondria important determinants of health and disease, and describe the pharmacological strategies being developed to address mitochondrial dysfunction.
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Affiliation(s)
- Robin A J Smith
- Department of Chemistry, University of Otago, Box 56, Dunedin, New Zealand
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24
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Spät A, Szanda G. Special features of mitochondrial Ca²⁺ signalling in adrenal glomerulosa cells. Pflugers Arch 2012; 464:43-50. [PMID: 22395411 DOI: 10.1007/s00424-012-1086-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 02/10/2012] [Accepted: 02/14/2012] [Indexed: 11/30/2022]
Abstract
Aldosterone, secreted by adrenal glomerulosa cells, allows the adaptation of the vertebrate organism to a wide range of physiological and pathological stimuli including acute haemodynamic challenges and long-term changes in dietary sodium and potassium intake. Most of the extracellular signals are mediated by cytosolic Ca²⁺ signal deriving from Ca²⁺ release, store-operated and/or voltage-gated Ca²⁺ influx. Mitochondria in glomerulosa cells play a fundamental role in generating and modulating the final biological response. These organelles not only house several enzymes of aldosterone biosynthesis but also-in a Ca²⁺-dependent manner-provide NADPH for the function of these enzymes. Moreover, mitochondria, constituting a high portion of cytoplasmic volume and displaying a uniquely low-threshold Ca²⁺ sequestering ability, shape and thus modulate the decoding of the complex cytosolic Ca²⁺ response. The unusual features of mitochondrial Ca²⁺ signalling that permit such an integrative function in adrenal glomerulosa cells are hereby described.
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Affiliation(s)
- András Spät
- Department of Physiology, Semmelweis University, Budapest, Hungary.
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25
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Mechanism of transcription initiation by the yeast mitochondrial RNA polymerase. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2012; 1819:930-8. [PMID: 22353467 DOI: 10.1016/j.bbagrm.2012.02.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 02/03/2012] [Accepted: 02/04/2012] [Indexed: 02/03/2023]
Abstract
Mitochondria are the major supplier of cellular energy in the form of ATP. Defects in normal ATP production due to dysfunctions in mitochondrial gene expression are responsible for many mitochondrial and aging related disorders. Mitochondria carry their own DNA genome which is transcribed by relatively simple transcriptional machinery consisting of the mitochondrial RNAP (mtRNAP) and one or more transcription factors. The mtRNAPs are remarkably similar in sequence and structure to single-subunit bacteriophage T7 RNAP but they require accessory transcription factors for promoter-specific initiation. Comparison of the mechanisms of T7 RNAP and mtRNAP provides a framework to better understand how mtRNAP and the transcription factors work together to facilitate promoter selection, DNA melting, initiating nucleotide binding, and promoter clearance. This review focuses primarily on the mechanistic characterization of transcription initiation by the yeast Saccharomyces cerevisiae mtRNAP (Rpo41) and its transcription factor (Mtf1) drawing insights from the homologous T7 and the human mitochondrial transcription systems. We discuss regulatory mechanisms of mitochondrial transcription and the idea that the mtRNAP acts as the in vivo ATP "sensor" to regulate gene expression. This article is part of a Special Issue entitled: Mitochondrial Gene Expression.
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26
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Trypanosomes and the solution to a 50-year mitochondrial calcium mystery. Trends Parasitol 2011; 28:31-7. [PMID: 22088944 DOI: 10.1016/j.pt.2011.10.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 10/19/2011] [Accepted: 10/19/2011] [Indexed: 12/29/2022]
Abstract
The ability of mitochondria to take up Ca(2+) was discovered 50 years ago. This calcium uptake, through a mitochondrial calcium uniporter (MCU), is important not only for the regulation of cellular ATP concentration but also for more complex pathways such as shaping Ca(2+) signals and the activation of programmed cell death. The molecular nature of the uniporter remained unknown for decades. By a comparative study of mitochondrial protein profiles of organisms lacking or possessing MCU, such as yeast in the former case and vertebrates and trypanosomes in the latter, two groups recently found the protein that possesses all the characteristics of the MCU. These results add another success story to the already substantial contributions of trypanosomes to mammalian biochemistry.
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