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de Andrade VM, de Oliveira VDM, Barcick U, Ramu VG, Heras M, Bardají ER, Castanho MARB, Zelanis A, Capella A, Junqueira JC, Conceição K. Mechanistic insights on the antibacterial action of the kyotorphin peptide derivatives revealed by in vitro studies and Galleria mellonella proteomic analysis. Microb Pathog 2024; 189:106607. [PMID: 38437995 DOI: 10.1016/j.micpath.2024.106607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/21/2024] [Accepted: 03/01/2024] [Indexed: 03/06/2024]
Abstract
OBJECTIVES The selected kyotorphin derivatives were tested to improve their antimicrobial and antibiofilm activity. The antimicrobial screening of the KTP derivatives were ascertained in the representative strains of bacteria, including Streptococcus pneumoniae, Streptococcus pyogenes, Escherichia coli and Pseudomonas aeruginosa. METHODS Kyotorphin derivatives, KTP-NH2, KTP-NH2-DL, IbKTP, IbKTP-NH2, MetKTP-DL, MetKTP-LD, were designed and synthesized to improve lipophilicity and resistance to enzymatic degradation. Peptides were synthesized by standard solution or solid-phase peptide synthesis and purified using RP-HPLC, which resulted in >95 % purity, and were fully characterized by mass spectrometry and 1H NMR. The minimum inhibitory concentrations (MIC) determined for bacterial strains were between 20 and 419 μM. The direct effect of IbKTP-NH2 on bacterial cells was imaged using scanning electron microscopy. The absence of toxicity, high survival after infection and an increase in the hemocytes count was evaluated by injections of derivatives in Galleria mellonella larvae. Proteomics analyses of G. mellonella hemolymph were performed to investigate the underlying mechanism of antibacterial activity of IbKTP-NH2 at MIC. RESULTS IbKTP-NH2 induces morphological changes in bacterial cell, many differentially expressed proteins involved in DNA replication, synthesis of cell wall, and virulence were up-regulated after the treatment of G. mellonella with IbKTP-NH2. CONCLUSION We suggest that this derivative, in addition to its physical activity on the bacterial membranes, can elicit a cellular and humoral immune response, therefore, it could be considered for biomedical applications.
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Affiliation(s)
- Vitor M de Andrade
- Laboratório de Bioquímica de Peptídeos, Departamento de Ciência e Tecnologia - Universidade Federal de São Paulo - UNIFESP, Rua Talim, 330, São José dos Campos, SP, 12231-280, Brazil
| | - Vitor D M de Oliveira
- Laboratório de Bioquímica de Peptídeos, Departamento de Ciência e Tecnologia - Universidade Federal de São Paulo - UNIFESP, Rua Talim, 330, São José dos Campos, SP, 12231-280, Brazil
| | - Uilla Barcick
- Laboratório de Proteômica Funcional, Departamento de Ciência e Tecnologia, Universidade Federal de São Paulo - Universidade Federal de São Paulo - UNIFESP, Rua Talim, 330, São José dos Campos, SP, 12231-280, Brazil
| | - Vasanthakumar G Ramu
- Laboratori d'Innovació en Processos i Productes de Síntesi Orgànica (LIPPSO), Departament de Química, Universitat de Girona, Campus Montilivi, 17071, Girona, Spain; Peptides and Complex Generics, #2700, Neovantage, Genome Valley, Shameerpet, Hyderabad, 500078, Telengana, India
| | - Montserrat Heras
- Laboratori d'Innovació en Processos i Productes de Síntesi Orgànica (LIPPSO), Departament de Química, Universitat de Girona, Campus Montilivi, 17071, Girona, Spain
| | - Eduard R Bardají
- Laboratori d'Innovació en Processos i Productes de Síntesi Orgànica (LIPPSO), Departament de Química, Universitat de Girona, Campus Montilivi, 17071, Girona, Spain
| | - Miguel A R B Castanho
- Instituto de Medicina Molecular, Faculdade de Medicina de Lisboa, Av. Professor Egas Moniz, 1649-028, Lisboa, Portugal
| | - André Zelanis
- Laboratório de Proteômica Funcional, Departamento de Ciência e Tecnologia, Universidade Federal de São Paulo - Universidade Federal de São Paulo - UNIFESP, Rua Talim, 330, São José dos Campos, SP, 12231-280, Brazil
| | - Aline Capella
- Laboratório ProLaser, Departamento de Ciência e Tecnologia, Universidade Federal de São Paulo - UNIFESP, Rua Talim, 330, São José dos Campos, SP, 12231-280, Brazil
| | - Juliana C Junqueira
- Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, São Paulo State University (Unesp), São José dos Campos, 12245-000, SP, Brazil
| | - Katia Conceição
- Laboratório de Bioquímica de Peptídeos, Departamento de Ciência e Tecnologia - Universidade Federal de São Paulo - UNIFESP, Rua Talim, 330, São José dos Campos, SP, 12231-280, Brazil.
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Caron-Godon CA, Collington E, Wolf JL, Coletta G, Glerum DM. More than Just Bread and Wine: Using Yeast to Understand Inherited Cytochrome Oxidase Deficiencies in Humans. Int J Mol Sci 2024; 25:3814. [PMID: 38612624 PMCID: PMC11011759 DOI: 10.3390/ijms25073814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/26/2024] [Accepted: 03/28/2024] [Indexed: 04/14/2024] Open
Abstract
Inherited defects in cytochrome c oxidase (COX) are associated with a substantial subset of diseases adversely affecting the structure and function of the mitochondrial respiratory chain. This multi-subunit enzyme consists of 14 subunits and numerous cofactors, and it requires the function of some 30 proteins to assemble. COX assembly was first shown to be the primary defect in the majority of COX deficiencies 36 years ago. Over the last three decades, most COX assembly genes have been identified in the yeast Saccharomyces cerevisiae, and studies in yeast have proven instrumental in testing the impact of mutations identified in patients with a specific COX deficiency. The advent of accessible genome-wide sequencing capabilities has led to more patient mutations being identified, with the subsequent identification of several new COX assembly factors. However, the lack of genotype-phenotype correlations and the large number of genes involved in generating a functional COX mean that functional studies must be undertaken to assign a genetic variant as being causal. In this review, we provide a brief overview of the use of yeast as a model system and briefly compare the COX assembly process in yeast and humans. We focus primarily on the studies in yeast that have allowed us to both identify new COX assembly factors and to demonstrate the pathogenicity of a subset of the mutations that have been identified in patients with inherited defects in COX. We conclude with an overview of the areas in which studies in yeast are likely to continue to contribute to progress in understanding disease arising from inherited COX deficiencies.
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Affiliation(s)
- Chenelle A. Caron-Godon
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - Emma Collington
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - Jessica L. Wolf
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - Genna Coletta
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - D. Moira Glerum
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
- Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
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3
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Rivett ED, Addis HG, Dietz JV, Carroll-Deaton JA, Gupta S, Foreman KL, Dang MA, Fox JL, Khalimonchuk O, Hegg EL. Evidence that the catalytic mechanism of heme a synthase involves the formation of a carbocation stabilized by a conserved glutamate. Arch Biochem Biophys 2023; 744:109665. [PMID: 37348627 PMCID: PMC10529832 DOI: 10.1016/j.abb.2023.109665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/24/2023]
Abstract
In eukaryotes and many aerobic prokaryotes, the final step of aerobic respiration is catalyzed by an aa3-type cytochrome c oxidase, which requires a modified heme cofactor, heme a. The conversion of heme b, the prototypical cellular heme, to heme o and ultimately to heme a requires two modifications, the latter of which is conversion of a methyl group to an aldehyde, catalyzed by heme a synthase (HAS). The N- and C-terminal halves of HAS share homology, and each half contains a heme-binding site. Previous reports indicate that the C-terminal site is occupied by a heme b cofactor. The N-terminal site may function as the substrate (heme o) binding site, although this has not been confirmed experimentally. Here, we assess the role of conserved residues from the N- and C-terminal heme-binding sites in HAS from prokaryotic (Shewanella oneidensis) and eukaryotic (Saccharomyces cerevisiae) species - SoHAS/CtaA and ScHAS/Cox15, respectively. A glutamate within the N-terminal site is found to be critical for activity in both types of HAS, consistent with the hypothesis that a carbocation forms transiently during catalysis. In contrast, the residue occupying the analogous C-terminal position is dispensable for enzyme activity. In SoHAS, the C-terminal heme ligands are critical for stability, while in ScHAS, substitutions in either heme-binding site have little effect on global structure. In both species, in vivo accumulation of heme o requires the presence of an inactive HAS variant, highlighting a potential regulatory role for HAS in heme o biosynthesis.
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Affiliation(s)
- Elise D Rivett
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Hannah G Addis
- Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC, 29424, USA
| | - Jonathan V Dietz
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA
| | - Jayda A Carroll-Deaton
- Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC, 29424, USA
| | - Shipra Gupta
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Koji L Foreman
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Minh Anh Dang
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Jennifer L Fox
- Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC, 29424, USA.
| | - Oleh Khalimonchuk
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA; Nebraska Redox Biology Center, University of Nebraska, Lincoln, NE, 68588, USA; Fred & Pamela Buffett Cancer Center, Omaha, NE, 68198, USA.
| | - Eric L Hegg
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA.
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Lopriore P, Gomes F, Montano V, Siciliano G, Mancuso M. Mitochondrial Epilepsy, a Challenge for Neurologists. Int J Mol Sci 2022; 23:ijms232113216. [PMID: 36362003 PMCID: PMC9656379 DOI: 10.3390/ijms232113216] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 10/26/2022] [Accepted: 10/27/2022] [Indexed: 01/29/2023] Open
Abstract
Primary mitochondrial diseases are relatively common inborn errors of energy metabolism, with a combined prevalence of 1 in 4300. These disorders typically affect tissues with high energy requirements, including the brain. Epilepsy affects >1% of the worldwide population, making it one of the most common neurological illnesses; it may be the presenting feature of a mitochondrial disease, but is often part of a multisystem clinical presentation. The major genetic causes of mitochondrial epilepsy are mutations in mitochondrial DNA and in the nuclear-encoded gene POLG. Treatment of mitochondrial epilepsy may be challenging, often representing a poor prognostic feature. This narrative review will cover the most recent advances in the field of mitochondrial epilepsy, from pathophysiology and genetic etiologies to phenotype and treatment options.
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Affiliation(s)
- Piervito Lopriore
- Neurological Institute, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Fábio Gomes
- Neurology Department, Coimbra University Hospital Centre, 3004-561 Coimbra, Portugal
| | - Vincenzo Montano
- Neurological Institute, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Gabriele Siciliano
- Neurological Institute, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Michelangelo Mancuso
- Neurological Institute, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
- Correspondence:
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5
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Wang L, Yang Z, He X, Pu S, Yang C, Wu Q, Zhou Z, Cen X, Zhao H. Mitochondrial protein dysfunction in pathogenesis of neurological diseases. Front Mol Neurosci 2022; 15:974480. [PMID: 36157077 PMCID: PMC9489860 DOI: 10.3389/fnmol.2022.974480] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/08/2022] [Indexed: 11/21/2022] Open
Abstract
Mitochondria are essential organelles for neuronal function and cell survival. Besides the well-known bioenergetics, additional mitochondrial roles in calcium signaling, lipid biogenesis, regulation of reactive oxygen species, and apoptosis are pivotal in diverse cellular processes. The mitochondrial proteome encompasses about 1,500 proteins encoded by both the nuclear DNA and the maternally inherited mitochondrial DNA. Mutations in the nuclear or mitochondrial genome, or combinations of both, can result in mitochondrial protein deficiencies and mitochondrial malfunction. Therefore, mitochondrial quality control by proteins involved in various surveillance mechanisms is critical for neuronal integrity and viability. Abnormal proteins involved in mitochondrial bioenergetics, dynamics, mitophagy, import machinery, ion channels, and mitochondrial DNA maintenance have been linked to the pathogenesis of a number of neurological diseases. The goal of this review is to give an overview of these pathways and to summarize the interconnections between mitochondrial protein dysfunction and neurological diseases.
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Affiliation(s)
- Liang Wang
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Ziyun Yang
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital of Sichuan University, Chengdu, China
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Xiumei He
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Shiming Pu
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Cheng Yang
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Qiong Wu
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Zuping Zhou
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Xiaobo Cen
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Hongxia Zhao
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
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6
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Rivett ED, Heo L, Feig M, Hegg EL. Biosynthesis and trafficking of heme o and heme a: new structural insights and their implications for reaction mechanisms and prenylated heme transfer. Crit Rev Biochem Mol Biol 2021; 56:640-668. [PMID: 34428995 DOI: 10.1080/10409238.2021.1957668] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Aerobic respiration is a key energy-producing pathway in many prokaryotes and virtually all eukaryotes. The final step of aerobic respiration is most commonly catalyzed by heme-copper oxidases embedded in the cytoplasmic or mitochondrial membrane. The majority of these terminal oxidases contain a prenylated heme (typically heme a or occasionally heme o) in the active site. In addition, many heme-copper oxidases, including mitochondrial cytochrome c oxidases, possess a second heme a cofactor. Despite the critical role of heme a in the electron transport chain, the details of the mechanism by which heme b, the prototypical cellular heme, is converted to heme o and then to heme a remain poorly understood. Recent structural investigations, however, have helped clarify some elements of heme a biosynthesis. In this review, we discuss the insight gained from these advances. In particular, we present a new structural model of heme o synthase (HOS) based on distance restraints from inferred coevolutionary relationships and refined by molecular dynamics simulations that are in good agreement with the experimentally determined structures of HOS homologs. We also analyze the two structures of heme a synthase (HAS) that have recently been solved by other groups. For both HOS and HAS, we discuss the proposed catalytic mechanisms and highlight how new insights into the heme-binding site locations shed light on previously obtained biochemical data. Finally, we explore the implications of the new structural data in the broader context of heme trafficking in the heme a biosynthetic pathway and heme-copper oxidase assembly.
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Affiliation(s)
- Elise D Rivett
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Lim Heo
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Michael Feig
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Eric L Hegg
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
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7
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Bakare AB, Lesnefsky EJ, Iyer S. Leigh Syndrome: A Tale of Two Genomes. Front Physiol 2021; 12:693734. [PMID: 34456746 PMCID: PMC8385445 DOI: 10.3389/fphys.2021.693734] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 07/22/2021] [Indexed: 12/21/2022] Open
Abstract
Leigh syndrome is a rare, complex, and incurable early onset (typically infant or early childhood) mitochondrial disorder with both phenotypic and genetic heterogeneity. The heterogeneous nature of this disorder, based in part on the complexity of mitochondrial genetics, and the significant interactions between the nuclear and mitochondrial genomes has made it particularly challenging to research and develop therapies. This review article discusses some of the advances that have been made in the field to date. While the prognosis is poor with no current substantial treatment options, multiple studies are underway to understand the etiology, pathogenesis, and pathophysiology of Leigh syndrome. With advances in available research tools leading to a better understanding of the mitochondria in health and disease, there is hope for novel treatment options in the future.
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Affiliation(s)
- Ajibola B. Bakare
- Department of Biological Sciences, J. William Fulbright College of Arts and Sciences, University of Arkansas, Fayetteville, AR, United States
| | - Edward J. Lesnefsky
- Division of Cardiology, Pauley Heart Center, Department of Internal Medicine, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
- Department of Physiology/Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Shilpa Iyer
- Department of Biological Sciences, J. William Fulbright College of Arts and Sciences, University of Arkansas, Fayetteville, AR, United States
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8
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Zanfardino P, Doccini S, Santorelli FM, Petruzzella V. Tackling Dysfunction of Mitochondrial Bioenergetics in the Brain. Int J Mol Sci 2021; 22:8325. [PMID: 34361091 PMCID: PMC8348117 DOI: 10.3390/ijms22158325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 12/15/2022] Open
Abstract
Oxidative phosphorylation (OxPhos) is the basic function of mitochondria, although the landscape of mitochondrial functions is continuously growing to include more aspects of cellular homeostasis. Thanks to the application of -omics technologies to the study of the OxPhos system, novel features emerge from the cataloging of novel proteins as mitochondrial thus adding details to the mitochondrial proteome and defining novel metabolic cellular interrelations, especially in the human brain. We focussed on the diversity of bioenergetics demand and different aspects of mitochondrial structure, functions, and dysfunction in the brain. Definition such as 'mitoexome', 'mitoproteome' and 'mitointeractome' have entered the field of 'mitochondrial medicine'. In this context, we reviewed several genetic defects that hamper the last step of aerobic metabolism, mostly involving the nervous tissue as one of the most prominent energy-dependent tissues and, as consequence, as a primary target of mitochondrial dysfunction. The dual genetic origin of the OxPhos complexes is one of the reasons for the complexity of the genotype-phenotype correlation when facing human diseases associated with mitochondrial defects. Such complexity clinically manifests with extremely heterogeneous symptoms, ranging from organ-specific to multisystemic dysfunction with different clinical courses. Finally, we briefly discuss the future directions of the multi-omics study of human brain disorders.
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Affiliation(s)
- Paola Zanfardino
- Department of Medical Basic Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, 70124 Bari, Italy;
| | - Stefano Doccini
- IRCCS Fondazione Stella Maris, Calambrone, 56128 Pisa, Italy;
| | | | - Vittoria Petruzzella
- Department of Medical Basic Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, 70124 Bari, Italy;
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9
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Galvão de Oliveira M, Tengan C, Micheletti C, Ramos de Macedo P, Soares Pinho Cernach MC, Cavole TR, de França Basto M, Filho JS, Virmond LA, Milanezi F, Nakano V, Falconi A, Perrone E. A novel variant in the COX15 gene causing a fatal infantile cardioencephalomyopathy: A case report with clinical and molecular review. Eur J Med Genet 2021; 64:104195. [PMID: 33746038 DOI: 10.1016/j.ejmg.2021.104195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 03/04/2021] [Accepted: 03/14/2021] [Indexed: 10/21/2022]
Abstract
The cytochrome c-oxidase (COX) enzyme, also known as mitochondrial complex IV (MT-C4D), is a transmembrane protein complex found in mitochondria. COX deficiency is one of the most frequent causes of electron transport chain defects in humans. Therefore, high energy demand organs and tissues are affected in patients with mutations in the COX15 gene, with variable phenotypic expressiveness. We describe the case of a male newborn with hypertrophic cardiomyopathy and serum and cerebrospinal fluid hyperlacticaemia, whose exome sequencing revealed two variants in a compound heterozygous state: c.232G > A; p.(Gly78Arg), classified as likely pathogenic, and c.452C > G; p.(Ser151Ter), as pathogenic; the former never previously described in the literature.
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Affiliation(s)
| | - Célia Tengan
- Universidade Federal de São Paulo, Unifesp, Departamento de Neurologia, São Paulo, SP, CEP 04039-000, Brazil.
| | - Cecília Micheletti
- Universidade Federal de São Paulo, Unifesp, Departamento de Pediatria, São Paulo, SP, CEP 04023-060, Brazil.
| | - Paloma Ramos de Macedo
- Universidade Federal de São Paulo, Unifesp, Departamento de Neurologia, São Paulo, SP, CEP 04039-000, Brazil.
| | | | - Thiago Rodrigues Cavole
- Universidade Federal de São Paulo, Unifesp, Departamento de Genética, São Paulo, SP, CEP 04023-061, Brazil.
| | - Marina de França Basto
- Universidade Federal de São Paulo, Unifesp, Departamento de Genética, São Paulo, SP, CEP 04023-061, Brazil.
| | - Joselito Sobreira Filho
- Universidade Federal de São Paulo, Unifesp, Departamento de Genética, São Paulo, SP, CEP 04023-061, Brazil.
| | - Luiza Amaral Virmond
- Universidade Federal de São Paulo, Unifesp, Departamento de Genética, São Paulo, SP, CEP 04023-061, Brazil.
| | | | | | | | - Eduardo Perrone
- Universidade Federal de São Paulo, Unifesp, Departamento de Genética, São Paulo, SP, CEP 04023-061, Brazil.
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10
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Fernandez-Vizarra E, Zeviani M. Mitochondrial disorders of the OXPHOS system. FEBS Lett 2020; 595:1062-1106. [PMID: 33159691 DOI: 10.1002/1873-3468.13995] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 10/21/2020] [Accepted: 11/01/2020] [Indexed: 12/13/2022]
Abstract
Mitochondrial disorders are among the most frequent inborn errors of metabolism, their primary cause being the dysfunction of the oxidative phosphorylation system (OXPHOS). OXPHOS is composed of the electron transport chain (ETC), formed by four multimeric enzymes and two mobile electron carriers, plus an ATP synthase [also called complex V (cV)]. The ETC performs the redox reactions involved in cellular respiration while generating the proton motive force used by cV to synthesize ATP. OXPHOS biogenesis involves multiple steps, starting from the expression of genes encoded in physically separated genomes, namely the mitochondrial and nuclear DNA, to the coordinated assembly of components and cofactors building each individual complex and eventually the supercomplexes. The genetic cause underlying around half of the diagnosed mitochondrial disease cases is currently known. Many of these cases result from pathogenic variants in genes encoding structural subunits or additional factors directly involved in the assembly of the ETC complexes. Here, we review the historical and most recent findings concerning the clinical phenotypes and the molecular pathological mechanisms underlying this particular group of disorders.
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Affiliation(s)
- Erika Fernandez-Vizarra
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Massimo Zeviani
- Venetian Institute of Molecular Medicine, Padova, Italy.,Department of Neurosciences, University of Padova, Italy
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11
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Human Mitochondrial Pathologies of the Respiratory Chain and ATP Synthase: Contributions from Studies of Saccharomyces cerevisiae. Life (Basel) 2020; 10:life10110304. [PMID: 33238568 PMCID: PMC7700678 DOI: 10.3390/life10110304] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/18/2020] [Accepted: 11/19/2020] [Indexed: 12/14/2022] Open
Abstract
The ease with which the unicellular yeast Saccharomyces cerevisiae can be manipulated genetically and biochemically has established this organism as a good model for the study of human mitochondrial diseases. The combined use of biochemical and molecular genetic tools has been instrumental in elucidating the functions of numerous yeast nuclear gene products with human homologs that affect a large number of metabolic and biological processes, including those housed in mitochondria. These include structural and catalytic subunits of enzymes and protein factors that impinge on the biogenesis of the respiratory chain. This article will review what is currently known about the genetics and clinical phenotypes of mitochondrial diseases of the respiratory chain and ATP synthase, with special emphasis on the contribution of information gained from pet mutants with mutations in nuclear genes that impair mitochondrial respiration. Our intent is to provide the yeast mitochondrial specialist with basic knowledge of human mitochondrial pathologies and the human specialist with information on how genes that directly and indirectly affect respiration were identified and characterized in yeast.
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12
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Cytochrome c oxidase deficiency. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148335. [PMID: 33171185 DOI: 10.1016/j.bbabio.2020.148335] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/31/2020] [Accepted: 11/03/2020] [Indexed: 12/23/2022]
Abstract
Cytochrome c oxidase (COX) deficiency is characterized by a high degree of genetic and phenotypic heterogeneity, partly reflecting the extreme structural complexity, multiple post-translational modification, variable, tissue-specific composition, and the high number of and intricate connections among the assembly factors of this enzyme. In fact, decreased COX specific activity can manifest with different degrees of severity, affect the whole organism or specific tissues, and develop a wide spectrum of disease natural history, including disease onsets ranging from birth to late adulthood. More than 30 genes have been linked to COX deficiency, but the list is still incomplete and in fact constantly updated. We here discuss the current knowledge about COX in health and disease, focusing on genetic aetiology and link to clinical manifestations. In addition, information concerning either fundamental biological features of the enzymes or biochemical signatures of its defects have been provided by experimental in vivo models, including yeast, fly, mouse and fish, which expanded our knowledge on the functional features and the phenotypical consequences of different forms of COX deficiency.
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13
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Raghavan S, Baskin DS, Sharpe MA. MP-Pt(IV): A MAOB-Sensitive Mitochondrial-Specific Prodrug for Treating Glioblastoma. Mol Cancer Ther 2020; 19:2445-2453. [PMID: 33033175 DOI: 10.1158/1535-7163.mct-20-0420] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 08/13/2020] [Accepted: 09/23/2020] [Indexed: 11/16/2022]
Abstract
We have previously reported the in vitro and in vivo efficacy of N,N-bis(2-chloroethyl)-2-(1-methyl-1,2,3,6-tetrahydropyridin-4-yl)propenamide (MP-MUS), a prodrug that targeted the mitochondria of glioblastoma (GBM). The mitochondrial enzyme, monoamine oxidase B (MAOB), is highly expressed in GBM and oxidizes an uncharged methyl-tetrahydropyridine (MP-) moiety into the mitochondrially targeted cationic form, methyl-pyridinium (P+-). Coupling this MAOB-sensitive group to a nitrogen mustard produced a prodrug that damaged GBM mitochondria and killed GBM cells. Unfortunately, the intrinsic reactivity of the nitrogen mustard group and low solubility of MP-MUS precluded clinical development. In our second-generation prodrug, MP-Pt(IV), we coupled the MP group to an unreactive cisplatin precursor. The enzymatic conversion of MP-Pt(IV) to P+-Pt(IV) was tested using recombinant human MAOA and rhMAOB. The generation of cisplatin from Pt(IV) by ascorbate was studied optically and using mass spectroscopy. Efficacy toward primary GBM cells and tumors was studied in vitro and in an intracranial patient-derived xenograft mice GBM model. Our studies demonstrate that MP-Pt(IV) is selectively activated by MAOB. MP-Pt(IV) is highly toxic toward GBM cells in vitro MP-Pt(IV) toxicity against GBM is potentiated by elevating mitochondrial ascorbate and can be arrested by MAOB inhibition. In in vitro studies, sublethal MP-Pt(IV) doses elevated mitochondrial MAOB levels in surviving GBM cells. MP-Pt(IV) is a potent chemotherapeutic in intracranial patient-derived xenograft mouse models of primary GBM and potentiates both temozolomide and temozolomide-chemoradiation therapies. MP-Pt(IV) was well tolerated and is highly effective against GBM in both in vitro and in vivo models.
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Affiliation(s)
- Sudhir Raghavan
- Kenneth R. Peak Brain and Pituitary Treatment Center and the Department of Neurosurgery, Houston Methodist Hospital, Houston, Texas.,Houston Methodist Research Institute, Houston, Texas
| | - David S Baskin
- Kenneth R. Peak Brain and Pituitary Treatment Center and the Department of Neurosurgery, Houston Methodist Hospital, Houston, Texas. .,Houston Methodist Research Institute, Houston, Texas
| | - Martyn A Sharpe
- Kenneth R. Peak Brain and Pituitary Treatment Center and the Department of Neurosurgery, Houston Methodist Hospital, Houston, Texas. .,Houston Methodist Research Institute, Houston, Texas
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14
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Functions of Cytochrome c oxidase Assembly Factors. Int J Mol Sci 2020; 21:ijms21197254. [PMID: 33008142 PMCID: PMC7582755 DOI: 10.3390/ijms21197254] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 09/23/2020] [Indexed: 12/22/2022] Open
Abstract
Cytochrome c oxidase is the terminal complex of eukaryotic oxidative phosphorylation in mitochondria. This process couples the reduction of electron carriers during metabolism to the reduction of molecular oxygen to water and translocation of protons from the internal mitochondrial matrix to the inter-membrane space. The electrochemical gradient formed is used to generate chemical energy in the form of adenosine triphosphate to power vital cellular processes. Cytochrome c oxidase and most oxidative phosphorylation complexes are the product of the nuclear and mitochondrial genomes. This poses a series of topological and temporal steps that must be completed to ensure efficient assembly of the functional enzyme. Many assembly factors have evolved to perform these steps for insertion of protein into the inner mitochondrial membrane, maturation of the polypeptide, incorporation of co-factors and prosthetic groups and to regulate this process. Much of the information about each of these assembly factors has been gleaned from use of the single cell eukaryote Saccharomyces cerevisiae and also mutations responsible for human disease. This review will focus on the assembly factors of cytochrome c oxidase to highlight some of the outstanding questions in the assembly of this vital enzyme complex.
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15
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Halperin D, Drabkin M, Wormser O, Yogev Y, Dolgin V, Shorer Z, Gradstein L, Shelef I, Flusser H, Birk OS. Phenotypic variability and mutation hotspot in COX15-related Leigh syndrome. Am J Med Genet A 2020; 182:1506-1512. [PMID: 32232962 DOI: 10.1002/ajmg.a.61577] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 11/05/2022]
Abstract
COX15 mutations were shown to underlie Leigh syndrome (LS), a progressive subacute necrotizing encephalopathy caused by defects in the mitochondrial respiratory chain. Here, two siblings of consanguineous kindred presented in infancy with a syndrome of hypotonia, nystagmus, psychomotor retardation, and pyramidal signs. Toward the end of their second year, both patients developed progressive quadriparesis, convulsions, and pseudobulbar palsy. Similar to two previously reported cases, one of the two affected siblings had severe hypertrophic obstructive cardiomyopathy, hearing loss, and no visual response. Through linkage analysis and whole-exome sequencing, we identified a homozygous p.R217W mutation in Cytochrome C oxidase assembly protein COX15 homolog. Consistent with the known heterogeneity of mitochondrial diseases in general and that of LS in particular, several phenotypic features were markedly distinguished between the affected siblings and in relation to previous reports of COX15 mutations. Interestingly, of the previously reported five cases of COX15-mutated patients, all of different ethnic origins, three had a p.R217W mutation. We highlight p.R217W as a hotspot mutation in COX15 and delineate the phenotypic variability, both between the patients we describe and in all cases reported to date.
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Affiliation(s)
- Daniel Halperin
- Faculty of Health Sciences, The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Max Drabkin
- Faculty of Health Sciences, The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ohad Wormser
- Faculty of Health Sciences, The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Yuval Yogev
- Faculty of Health Sciences, The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Vadim Dolgin
- Faculty of Health Sciences, The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Zamir Shorer
- Pediatric Neurology Unit, Division of Pediatrics, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Libe Gradstein
- Department of Ophthalmology, Soroka University Medical Center and Clalit Health Services, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ilan Shelef
- Faculty of Health Sciences, Department of Imaging, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Hagit Flusser
- Zusman Child Development Center, Division of Pediatrics, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ohad S Birk
- Faculty of Health Sciences, The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Genetics Institute, Soroka University Medical Center, Beer-Sheva, Israel
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16
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From Synthesis to Utilization: The Ins and Outs of Mitochondrial Heme. Cells 2020; 9:cells9030579. [PMID: 32121449 PMCID: PMC7140478 DOI: 10.3390/cells9030579] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/19/2020] [Accepted: 02/23/2020] [Indexed: 12/14/2022] Open
Abstract
Heme is a ubiquitous and essential iron containing metallo-organic cofactor required for virtually all aerobic life. Heme synthesis is initiated and completed in mitochondria, followed by certain covalent modifications and/or its delivery to apo-hemoproteins residing throughout the cell. While the biochemical aspects of heme biosynthetic reactions are well understood, the trafficking of newly synthesized heme—a highly reactive and inherently toxic compound—and its subsequent delivery to target proteins remain far from clear. In this review, we summarize current knowledge about heme biosynthesis and trafficking within and outside of the mitochondria.
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17
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Sacchetto C, Sequeira V, Bertero E, Dudek J, Maack C, Calore M. Metabolic Alterations in Inherited Cardiomyopathies. J Clin Med 2019; 8:jcm8122195. [PMID: 31842377 PMCID: PMC6947282 DOI: 10.3390/jcm8122195] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 12/12/2022] Open
Abstract
The normal function of the heart relies on a series of complex metabolic processes orchestrating the proper generation and use of energy. In this context, mitochondria serve a crucial role as a platform for energy transduction by supplying ATP to the varying demand of cardiomyocytes, involving an intricate network of pathways regulating the metabolic flux of substrates. The failure of these processes results in structural and functional deficiencies of the cardiac muscle, including inherited cardiomyopathies. These genetic diseases are characterized by cardiac structural and functional anomalies in the absence of abnormal conditions that can explain the observed myocardial abnormality, and are frequently associated with heart failure. Since their original description, major advances have been achieved in the genetic and phenotype knowledge, highlighting the involvement of metabolic abnormalities in their pathogenesis. This review provides a brief overview of the role of mitochondria in the energy metabolism in the heart and focuses on metabolic abnormalities, mitochondrial dysfunction, and storage diseases associated with inherited cardiomyopathies.
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Affiliation(s)
- Claudia Sacchetto
- IMAiA—Institute for Molecular Biology and RNA Technology, Faculty of Health, Universiteitssingel 50, 6229ER Maastricht, The Netherlands;
- Medicine and Life Sciences, Faculty of Science and Engineering, Universiteitssingel 50, 6229ER Maastricht, The Netherlands
- Department of Biology, University of Padova, via Ugo Bassi 58B, 35121 Padova, Italy
| | - Vasco Sequeira
- Department of Translational Science, Comprehensive Heart Failure Center, University Clinic Würzburg, Am Schwarzenberg 15, 9708 Würzburg, Germany; (V.S.); (E.B.); (J.D.)
| | - Edoardo Bertero
- Department of Translational Science, Comprehensive Heart Failure Center, University Clinic Würzburg, Am Schwarzenberg 15, 9708 Würzburg, Germany; (V.S.); (E.B.); (J.D.)
| | - Jan Dudek
- Department of Translational Science, Comprehensive Heart Failure Center, University Clinic Würzburg, Am Schwarzenberg 15, 9708 Würzburg, Germany; (V.S.); (E.B.); (J.D.)
| | - Christoph Maack
- Department of Translational Science, Comprehensive Heart Failure Center, University Clinic Würzburg, Am Schwarzenberg 15, 9708 Würzburg, Germany; (V.S.); (E.B.); (J.D.)
- Correspondence: (C.M.); (M.C.)
| | - Martina Calore
- IMAiA—Institute for Molecular Biology and RNA Technology, Faculty of Health, Universiteitssingel 50, 6229ER Maastricht, The Netherlands;
- Medicine and Life Sciences, Faculty of Science and Engineering, Universiteitssingel 50, 6229ER Maastricht, The Netherlands
- Correspondence: (C.M.); (M.C.)
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18
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Zhou Z, Austin GL, Young LEA, Johnson LA, Sun R. Mitochondrial Metabolism in Major Neurological Diseases. Cells 2018; 7:E229. [PMID: 30477120 PMCID: PMC6316877 DOI: 10.3390/cells7120229] [Citation(s) in RCA: 36] [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: 11/05/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 01/18/2023] Open
Abstract
Mitochondria are bilayer sub-cellular organelles that are an integral part of normal cellular physiology. They are responsible for producing the majority of a cell's ATP, thus supplying energy for a variety of key cellular processes, especially in the brain. Although energy production is a key aspect of mitochondrial metabolism, its role extends far beyond energy production to cell signaling and epigenetic regulation⁻functions that contribute to cellular proliferation, differentiation, apoptosis, migration, and autophagy. Recent research on neurological disorders suggest a major metabolic component in disease pathophysiology, and mitochondria have been shown to be in the center of metabolic dysregulation and possibly disease manifestation. This review will discuss the basic functions of mitochondria and how alterations in mitochondrial activity lead to neurological disease progression.
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Affiliation(s)
- Zhengqiu Zhou
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
| | - Grant L Austin
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
| | - Lyndsay E A Young
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
| | - Lance A Johnson
- Department of Physiology, University of Kentucky, Lexington, KY 40536, USA.
| | - Ramon Sun
- Molecular & Cellular Biochemistry Department, University of Kentucky, Lexington, KY 40536, USA.
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19
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Bilateral persistent fetal vasculature and a chromosome 10 mutation including COX15. Can J Ophthalmol 2017; 52:e203-e205. [DOI: 10.1016/j.jcjo.2017.04.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 04/24/2017] [Accepted: 04/28/2017] [Indexed: 11/18/2022]
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20
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Liu N, Irvin MR, Zhi D, Patki A, Beasley TM, Nickerson DA, Hill CE, Chen J, Kimmel SE, Limdi NA. Influence of common and rare genetic variation on warfarin dose among African-Americans and European-Americans using the exome array. Pharmacogenomics 2017; 18:1059-1073. [PMID: 28686080 DOI: 10.2217/pgs-2017-0046] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
AIM We conducted a genome-wide association study using the Illumina Exome Array to identify coding SNPs that may explain additional warfarin dose variability. PATIENTS & METHODS Analysis was performed after adjustment for clinical variables and genetic factors known to influence warfarin dose among 1680 warfarin users (838 European-Americans and 842 African-Americans). Replication was performed in an independent sample. RESULTS We confirmed the influence of known genetic variants on warfarin dose variability. Our study is the first to show the association between rs12772169 and warfarin dose in African-Americans. In addition, genes COX15 and FGF5 showed significant association in European-Americans. CONCLUSION We identified some novel genes/SNPs that underpin warfarin dose response. Further replication is needed to confirm our findings.
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Affiliation(s)
- Nianjun Liu
- Department of Epidemiology & Biostatistics, School of Public Health - Bloomington, Indiana University, Bloomington, IN 47405, USA
| | - Marguerite R Irvin
- Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Degui Zhi
- School of Biomedical Informatics, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Amit Patki
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - T Mark Beasley
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Deborah A Nickerson
- Department of Genome Sciences, School of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Charles E Hill
- Department of Pathology & Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jinbo Chen
- Department of Biostatistics & Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Stephen E Kimmel
- Department of Biostatistics & Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nita A Limdi
- Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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21
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Miryounesi M, Fardaei M, Tabei SM, Ghafouri-Fard S. Leigh syndrome associated with a novel mutation in the COX15 gene. J Pediatr Endocrinol Metab 2016; 29:741-4. [PMID: 26959537 DOI: 10.1515/jpem-2015-0396] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 01/04/2016] [Indexed: 11/15/2022]
Abstract
Leigh syndrome (LS) is a subacute necrotizing encephalomyelopathy with a diverse range of symptoms, such as psychomotor delay or regression, weakness, hypotonia, truncal ataxia, intention tremor as well as lactic acidosis in the blood, cerebrospinal fluid or urine. Both nuclear gene defects and mutations of the mitochondrial genome have been detected in these patients. Here we report a 7-year-old girl with hypotonia, tremor, developmental delay and psychomotor regression. However, serum lactate level as well as brain magnetic resonance imaging were normal. Mutational analysis has revealed a novel mutation in exon 4 of COX15 gene (c.415C>G) which results in p.Leu139Val. Previous studies have demonstrated that COX15 mutations are associated with typical LS as well as fatal infantile hypertrophic cardiomyopathy. Consequently, clinical manifestations of COX15 mutations may be significantly different in patients. Such information is of practical importance in genetic counseling.
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22
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Swenson S, Cannon A, Harris NJ, Taylor NG, Fox JL, Khalimonchuk O. Analysis of Oligomerization Properties of Heme a Synthase Provides Insights into Its Function in Eukaryotes. J Biol Chem 2016; 291:10411-25. [PMID: 26940873 DOI: 10.1074/jbc.m115.707539] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Indexed: 11/06/2022] Open
Abstract
Heme a is an essential cofactor for function of cytochrome c oxidase in the mitochondrial electron transport chain. Several evolutionarily conserved enzymes have been implicated in the biosynthesis of heme a, including the heme a synthase Cox15. However, the structure of Cox15 is unknown, its enzymatic mechanism and the role of active site residues remain debated, and recent discoveries suggest additional chaperone-like roles for this enzyme. Here, we investigated Cox15 in the model eukaryote Saccharomyces cerevisiae via several approaches to examine its oligomeric states and determine the effects of active site and human pathogenic mutations. Our results indicate that Cox15 exhibits homotypic interactions, forming highly stable complexes dependent upon hydrophobic interactions. This multimerization is evolutionarily conserved and independent of heme levels and heme a synthase catalytic activity. Four conserved histidine residues are demonstrated to be critical for eukaryotic heme a synthase activity and cannot be substituted with other heme-ligating amino acids. The 20-residue linker region connecting the two conserved domains of Cox15 is also important; removal of this linker impairs both Cox15 multimerization and enzymatic activity. Mutations of COX15 causing single amino acid conversions associated with fatal infantile hypertrophic cardiomyopathy and the neurological disorder Leigh syndrome result in impaired stability (S344P) or catalytic function (R217W), and the latter mutation affects oligomeric properties of the enzyme. Structural modeling of Cox15 suggests these two mutations affect protein folding and heme binding, respectively. We conclude that Cox15 multimerization is important for heme a biosynthesis and/or transfer to maturing cytochrome c oxidase.
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Affiliation(s)
- Samantha Swenson
- From the Department of Biochemistry and Nebraska Redox Biology Center, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 and
| | - Andrew Cannon
- From the Department of Biochemistry and Nebraska Redox Biology Center, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 and
| | - Nicholas J Harris
- the Department of Chemistry and Biochemistry, College of Charleston, Charleston, South Carolina 29424
| | - Nicholas G Taylor
- the Department of Chemistry and Biochemistry, College of Charleston, Charleston, South Carolina 29424
| | - Jennifer L Fox
- the Department of Chemistry and Biochemistry, College of Charleston, Charleston, South Carolina 29424
| | - Oleh Khalimonchuk
- From the Department of Biochemistry and Nebraska Redox Biology Center, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 and
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23
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Rak M, Bénit P, Chrétien D, Bouchereau J, Schiff M, El-Khoury R, Tzagoloff A, Rustin P. Mitochondrial cytochrome c oxidase deficiency. Clin Sci (Lond) 2016; 130:393-407. [PMID: 26846578 PMCID: PMC4948581 DOI: 10.1042/cs20150707] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
As with other mitochondrial respiratory chain components, marked clinical and genetic heterogeneity is observed in patients with a cytochrome c oxidase deficiency. This constitutes a considerable diagnostic challenge and raises a number of puzzling questions. So far, pathological mutations have been reported in more than 30 genes, in both mitochondrial and nuclear DNA, affecting either structural subunits of the enzyme or proteins involved in its biogenesis. In this review, we discuss the possible causes of the discrepancy between the spectacular advances made in the identification of the molecular bases of cytochrome oxidase deficiency and the lack of any efficient treatment in diseases resulting from such deficiencies. This brings back many unsolved questions related to the frequent delay of clinical manifestation, variable course and severity, and tissue-involvement often associated with these diseases. In this context, we stress the importance of studying different models of these diseases, but also discuss the limitations encountered in most available disease models. In the future, with the possible exception of replacement therapy using genes, cells or organs, a better understanding of underlying mechanism(s) of these mitochondrial diseases is presumably required to develop efficient therapy.
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Affiliation(s)
- Malgorzata Rak
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Paule Bénit
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Dominique Chrétien
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Juliette Bouchereau
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Manuel Schiff
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Reference Center for Inherited Metabolic Diseases, Hôpital Robert Debré, Assistance Publique-Hôpitaux de Paris, 48 Boulevard Sérurier, 75019 Paris, France
| | - Riyad El-Khoury
- American University of Beirut Medical Center, Department of Pathology and Laboratory Medicine, Cairo Street, Hamra, Beirut, Lebanon
| | - Alexander Tzagoloff
- Biological Sciences Department, Columbia University, New York, NY 10027, U.S.A
| | - Pierre Rustin
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
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24
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Gerards M, Sallevelt SCEH, Smeets HJM. Leigh syndrome: Resolving the clinical and genetic heterogeneity paves the way for treatment options. Mol Genet Metab 2016; 117:300-12. [PMID: 26725255 DOI: 10.1016/j.ymgme.2015.12.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/14/2015] [Accepted: 12/15/2015] [Indexed: 12/31/2022]
Abstract
Leigh syndrome is a progressive neurodegenerative disorder, affecting 1 in 40,000 live births. Most patients present with symptoms between the ages of three and twelve months, but adult onset Leigh syndrome has also been described. The disease course is characterized by a rapid deterioration of cognitive and motor functions, in most cases resulting in death due to respiratory failure. Despite the high genetic heterogeneity of Leigh syndrome, patients present with identical, symmetrical lesions in the basal ganglia or brainstem on MRI, while additional clinical manifestations and age of onset varies from case to case. To date, mutations in over 60 genes, both nuclear and mitochondrial DNA encoded, have been shown to cause Leigh syndrome, still explaining only half of all cases. In most patients, these mutations directly or indirectly affect the activity of the mitochondrial respiratory chain or pyruvate dehydrogenase complex. Exome sequencing has accelerated the discovery of new genes and pathways involved in Leigh syndrome, providing novel insights into the pathophysiological mechanisms. This is particularly important as no general curative treatment is available for this devastating disorder, although several recent studies imply that early treatment might be beneficial for some patients depending on the gene or process affected. Timely, gene-based personalized treatment may become an important strategy in rare, genetically heterogeneous disorders like Leigh syndrome, stressing the importance of early genetic diagnosis and identification of new genes/pathways. In this review, we provide a comprehensive overview of the most important clinical manifestations and genes/pathways involved in Leigh syndrome, and discuss the current state of therapeutic interventions in patients.
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Affiliation(s)
- Mike Gerards
- Department of Clinical Genetics, Research School GROW, Maastricht University Medical Centre, Maastricht, The Netherlands; Maastricht Center for Systems Biology (MaCSBio), Maastricht University Medical Centre, Maastricht, The Netherlands.
| | - Suzanne C E H Sallevelt
- Department of Clinical Genetics, Research School GROW, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Hubert J M Smeets
- Department of Clinical Genetics, Research School GROW, Maastricht University Medical Centre, Maastricht, The Netherlands
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Oláhová M, Hardy SA, Hall J, Yarham JW, Haack TB, Wilson WC, Alston CL, He L, Aznauryan E, Brown RM, Brown GK, Morris AAM, Mundy H, Broomfield A, Barbosa IA, Simpson MA, Deshpande C, Moeslinger D, Koch J, Stettner GM, Bonnen PE, Prokisch H, Lightowlers RN, McFarland R, Chrzanowska-Lightowlers ZMA, Taylor RW. LRPPRC mutations cause early-onset multisystem mitochondrial disease outside of the French-Canadian population. Brain 2015; 138:3503-19. [PMID: 26510951 PMCID: PMC4655343 DOI: 10.1093/brain/awv291] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 08/11/2015] [Indexed: 12/27/2022] Open
Abstract
The French-Canadian variant of COX-deficient Leigh syndrome (LSFC) is unique to Québec and caused by a founder mutation in the LRPPRC gene. Using whole exome sequencing, Oláhová et al. identify mutations in this gene associated with multisystem mitochondrial disease and early-onset neurodevelopmental problems in ten patients from different ethnic backgrounds. Mitochondrial Complex IV [cytochrome c oxidase (COX)] deficiency is one of the most common respiratory chain defects in humans. The clinical phenotypes associated with COX deficiency include liver disease, cardiomyopathy and Leigh syndrome, a neurodegenerative disorder characterized by bilateral high signal lesions in the brainstem and basal ganglia. COX deficiency can result from mutations affecting many different mitochondrial proteins. The French-Canadian variant of COX-deficient Leigh syndrome is unique to the Saguenay-Lac-Saint-Jean region of Québec and is caused by a founder mutation in the LRPPRC gene. This encodes the leucine-rich pentatricopeptide repeat domain protein (LRPPRC), which is involved in post-transcriptional regulation of mitochondrial gene expression. Here, we present the clinical and molecular characterization of novel, recessive LRPPRC gene mutations, identified using whole exome and candidate gene sequencing. The 10 patients come from seven unrelated families of UK-Caucasian, UK-Pakistani, UK-Indian, Turkish and Iraqi origin. They resemble the French-Canadian Leigh syndrome patients in having intermittent severe lactic acidosis and early-onset neurodevelopmental problems with episodes of deterioration. In addition, many of our patients have had neonatal cardiomyopathy or congenital malformations, most commonly affecting the heart and the brain. All patients who were tested had isolated COX deficiency in skeletal muscle. Functional characterization of patients’ fibroblasts and skeletal muscle homogenates showed decreased levels of mutant LRPPRC protein and impaired Complex IV enzyme activity, associated with abnormal COX assembly and reduced steady-state levels of numerous oxidative phosphorylation subunits. We also identified a Complex I assembly defect in skeletal muscle, indicating different roles for LRPPRC in post-transcriptional regulation of mitochondrial mRNAs between tissues. Patient fibroblasts showed decreased steady-state levels of mitochondrial mRNAs, although the length of poly(A) tails of mitochondrial transcripts were unaffected. Our study identifies LRPPRC as an important disease-causing gene in an early-onset, multisystem and neurological mitochondrial disease, which should be considered as a cause of COX deficiency even in patients originating outside of the French-Canadian population.
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Affiliation(s)
- Monika Oláhová
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Steven A Hardy
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Julie Hall
- 2 Department of Neuroradiology, Royal Victoria Infirmary, Newcastle upon Tyne, NE1 3BZ, UK
| | - John W Yarham
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Tobias B Haack
- 3 Institute of Human Genetics, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany 4 Institut für Humangenetik, Technische Universität München, Arcisstrasse 21, 80333 Munich, Germany
| | - William C Wilson
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Charlotte L Alston
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Langping He
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Erik Aznauryan
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Ruth M Brown
- 5 Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Garry K Brown
- 5 Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Andrew A M Morris
- 6 Willink Biochemical Genetics Unit, Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester, M13 9WL, UK
| | - Helen Mundy
- 7 Centre for Inherited Metabolic Disease, Evelina Children's Hospital, Guy's and St. Thomas' NHS Foundation Trust, London, SE1 7EH, UK
| | - Alex Broomfield
- 6 Willink Biochemical Genetics Unit, Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester, M13 9WL, UK
| | - Ines A Barbosa
- 8 Division of Genetics and Molecular Medicine, King's College London School of Medicine, London, SE1 9RY, UK
| | - Michael A Simpson
- 8 Division of Genetics and Molecular Medicine, King's College London School of Medicine, London, SE1 9RY, UK
| | - Charu Deshpande
- 9 Department of Genetics, Guy's and St. Thomas' NHS Foundation Trust, London, SE1 9RT, UK
| | - Dorothea Moeslinger
- 10 Department of Paediatrics, University Children's Hospital, A-1090 Vienna, Austria
| | - Johannes Koch
- 11 Department of Paediatrics, Paracelsus Medical University Salzburg, 5020 Salzburg, Austria
| | - Georg M Stettner
- 12 Department of Paediatric Neurology, Georg August University, 37075 Göttingen, Germany
| | - Penelope E Bonnen
- 13 Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Holger Prokisch
- 3 Institute of Human Genetics, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany 4 Institut für Humangenetik, Technische Universität München, Arcisstrasse 21, 80333 Munich, Germany
| | - Robert N Lightowlers
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Robert McFarland
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | | | - Robert W Taylor
- 1 Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
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Torraco A, Peralta S, Iommarini L, Diaz F. Mitochondrial Diseases Part I: mouse models of OXPHOS deficiencies caused by defects in respiratory complex subunits or assembly factors. Mitochondrion 2015; 21:76-91. [PMID: 25660179 DOI: 10.1016/j.mito.2015.01.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 11/22/2014] [Accepted: 01/05/2015] [Indexed: 10/24/2022]
Abstract
Mitochondrial disorders are the most common inborn errors of metabolism affecting the oxidative phosphorylation system (OXPHOS). Because of the poor knowledge of the pathogenic mechanisms, a cure for these disorders is still unavailable and all the treatments currently in use are supportive more than curative. Therefore, in the past decade a great variety of mouse models have been developed to assess the in vivo function of several mitochondrial proteins involved in human diseases. Due to the genetic and physiological similarity to humans, mice represent reliable models to study the pathogenic mechanisms of mitochondrial disorders and are precious to test new therapeutic approaches. Here we summarize the features of several mouse models of mitochondrial diseases directly related to defects in subunits of the OXPHOS complexes or in assembly factors. We discuss how these models recapitulate many human conditions and how they have contributed to the understanding of mitochondrial function in health and disease.
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Affiliation(s)
- Alessandra Torraco
- Unit for Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital, IRCCS, Viale di San Paolo, 15-00146 Rome, Italy.
| | - Susana Peralta
- Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA.
| | - Luisa Iommarini
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, Via Irnerio 42, 40126 Bologna, Italy.
| | - Francisca Diaz
- Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA.
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27
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Genetics of mitochondrial respiratory chain deficiencies. Rev Neurol (Paris) 2014; 170:309-22. [DOI: 10.1016/j.neurol.2013.11.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 11/27/2013] [Indexed: 01/21/2023]
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Lim S, Smith K, Stroud D, Compton A, Tucker E, Dasvarma A, Gandolfo L, Marum J, McKenzie M, Peters H, Mowat D, Procopis P, Wilcken B, Christodoulou J, Brown G, Ryan M, Bahlo M, Thorburn D. A founder mutation in PET100 causes isolated complex IV deficiency in Lebanese individuals with Leigh syndrome. Am J Hum Genet 2014; 94:209-22. [PMID: 24462369 DOI: 10.1016/j.ajhg.2013.12.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 12/18/2013] [Indexed: 12/30/2022] Open
Abstract
Leigh syndrome (LS) is a severe neurodegenerative disorder with characteristic bilateral lesions, typically in the brainstem and basal ganglia. It usually presents in infancy and is genetically heterogeneous, but most individuals with mitochondrial complex IV (or cytochrome c oxidase) deficiency have mutations in the biogenesis factor SURF1. We studied eight complex IV-deficient LS individuals from six families of Lebanese origin. They differed from individuals with SURF1 mutations in having seizures as a prominent feature. Complementation analysis suggested they had mutation(s) in the same gene but targeted massively parallel sequencing (MPS) of 1,034 genes encoding known mitochondrial proteins failed to identify a likely candidate. Linkage and haplotype analyses mapped the location of the gene to chromosome 19 and targeted MPS of the linkage region identified a homozygous c.3G>C (p.Met1?) mutation in C19orf79. Abolishing the initiation codon could potentially still allow initiation at a downstream methionine residue but we showed that this would not result in a functional protein. We confirmed that mutation of this gene was causative by lentiviral-mediated phenotypic correction. C19orf79 was recently renamed PET100 and predicted to encode a complex IV biogenesis factor. We showed that it is located in the mitochondrial inner membrane and forms a ∼300 kDa subcomplex with complex IV subunits. Previous proteomic analyses of mitochondria had overlooked PET100 because its small size was below the cutoff for annotating bona fide proteins. The mutation was estimated to have arisen at least 520 years ago, explaining how the families could have different religions and different geographic origins within Lebanon.
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Mourier A, Ruzzenente B, Brandt T, Kühlbrandt W, Larsson NG. Loss of LRPPRC causes ATP synthase deficiency. Hum Mol Genet 2014; 23:2580-92. [PMID: 24399447 PMCID: PMC3990160 DOI: 10.1093/hmg/ddt652] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Defects of the oxidative phosphorylation system, in particular of cytochrome-c oxidase (COX, respiratory chain complex IV), are common causes of Leigh syndrome (LS), which is a rare neurodegenerative disorder with severe progressive neurological symptoms that usually present during infancy or early childhood. The COX-deficient form of LS is commonly caused by mutations in genes encoding COX assembly factors, e.g. SURF1, SCO1, SCO2 or COX10. However, other mutations affecting genes that encode proteins not directly involved in COX assembly can also cause LS. The leucine-rich pentatricopeptide repeat containing protein (LRPPRC) regulates mRNA stability, polyadenylation and coordinates mitochondrial translation. In humans, mutations in Lrpprc cause the French Canadian type of LS. Despite the finding that LRPPRC deficiency affects the stability of most mitochondrial mRNAs, its pathophysiological effect has mainly been attributed to COX deficiency. Surprisingly, we show here that the impaired mitochondrial respiration and reduced ATP production observed in Lrpprc conditional knockout mouse hearts is caused by an ATP synthase deficiency. Furthermore, the appearance of inactive subassembled ATP synthase complexes causes hyperpolarization and increases mitochondrial reactive oxygen species production. Our findings shed important new light on the bioenergetic consequences of the loss of LRPPRC in cardiac mitochondria.
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Affiliation(s)
- Arnaud Mourier
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, Cologne 50931, Germany and
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DiMauro S, Tanji K, Schon EA. The Many Clinical Faces of Cytochrome c Oxidase Deficiency. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 748:341-57. [DOI: 10.1007/978-1-4614-3573-0_14] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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31
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Abstract
Most mitochondrial cytopathies in infants are caused by mutations in nuclear genes encoding proteins targeted to the mitochondria rather than by primary mutations in the mitochondrial DNA. Over the past few years, the awareness of the number of disease-causing mutations in different nuclear genes has grown exponentially. These genes encode the various subunits of each respiratory chain complex, the ancillary proteins involved in the assembly of these subunits, proteins involved in mitochondrial DNA replication and maintenance, proteins involved in mitochondrial protein synthesis, and proteins involved in mitochondrial dynamics. This increased awareness has added a challenging dimension to the current diagnostic workup of mitochondrial cytopathies. The advent of new technologies such as next-generation sequencing should facilitate the resolution of this dilemma.
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Affiliation(s)
- Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
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32
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Abstract
Mitochondrial diseases involve the dysfunction of the oxidative phosphorylation (OXPHOS) system. This group of diseases presents with heterogeneous clinical symptoms affecting mainly organs with high energy demands. Defects in the multimeric complexes comprising the OXPHOS system have a dual genetic origin, mitochondrial or nuclear DNA. Although many nuclear DNA mutations involve genes coding for subunits of the respiratory complexes, the majority of mutations found to date affect factors that do not form part of the final complexes. These assembly factors or chaperones have multiple functions ranging from cofactor insertion to proper assembly/stability of the complexes. Although significant progress has been made in the last few years in the discovery of new assembly factors, the function of many remains elusive. Here, we describe assembly factors or chaperones that are required for respiratory chain complex assembly and their clinical relevance.
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Alfadhel M, Lillquist YP, Waters PJ, Sinclair G, Struys E, McFadden D, Hendson G, Hyams L, Shoffner J, Vallance HD. Infantile cardioencephalopathy due to a COX15 gene defect: Report and review. Am J Med Genet A 2011; 155A:840-4. [DOI: 10.1002/ajmg.a.33881] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 12/09/2010] [Indexed: 11/10/2022]
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Genetic bases of mitochondrial respiratory chain disorders. DIABETES & METABOLISM 2010; 36:97-107. [PMID: 20093061 DOI: 10.1016/j.diabet.2009.11.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 11/09/2009] [Accepted: 11/10/2009] [Indexed: 01/21/2023]
Abstract
Oxidative phosphorylation - ATP synthesis by the oxygen-consuming respiratory chain (RC) - supplies most organs and tissues with a readily usable energy source, and is already fully functioning at birth. This means that, in theory, RC deficiency can give rise to any symptom in any organ or tissue at any age and with any mode of inheritance, due to the two-fold genetic origin of RC components (nuclear DNA and mitochondrial DNA). It has long been erroneously believed that RC disorders originate from mutations of mtDNA as, for some time, only mutations or deletions of mtDNA could be identified. However, the number of disease-causing mutations in nuclear genes is now steadily growing. These genes not only encode the various subunits of each complex, but also the ancillary proteins involved in the different stages of holoenzyme biogenesis, including transcription, translation, chaperoning, addition of prosthetic groups and assembly of proteins, as well as the various enzymes involved in mtDNA metabolism.
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Ugalde C, Morán M, Blázquez A, Arenas J, Martín MA. Mitochondrial Disorders Due to Nuclear OXPHOS Gene Defects. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 652:85-116. [DOI: 10.1007/978-90-481-2813-6_7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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36
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Diaz F. Cytochrome c oxidase deficiency: patients and animal models. Biochim Biophys Acta Mol Basis Dis 2009; 1802:100-10. [PMID: 19682572 DOI: 10.1016/j.bbadis.2009.07.013] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 07/30/2009] [Accepted: 07/31/2009] [Indexed: 12/17/2022]
Abstract
Cytochrome c oxidase (COX) deficiencies are one of the most common defects of the respiratory chain found in mitochondrial diseases. COX is a multimeric inner mitochondrial membrane enzyme formed by subunits encoded by both the nuclear and the mitochondrial genome. COX biosynthesis requires numerous assembly factors that do not form part of the final complex but participate in prosthetic group synthesis and metal delivery in addition to membrane insertion and maturation of COX subunits. Human diseases associated with COX deficiency including encephalomyopathies, Leigh syndrome, hypertrophic cardiomyopathies, and fatal lactic acidosis are caused by mutations in COX subunits or assembly factors. In the last decade, numerous animal models have been created to understand the pathophysiology of COX deficiencies and the function of assembly factors. These animal models, ranging from invertebrates to mammals, in most cases mimic the pathological features of the human diseases.
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Affiliation(s)
- Francisca Diaz
- Department of Neurology, University of Miami Miller School of Medicine, 1095 NW 14th Terrace, Miami, Florida 33136, USA.
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37
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Gerards M, Sluiter W, van den Bosch BJC, de Wit LEA, Calis CMH, Frentzen M, Akbari H, Schoonderwoerd K, Scholte HR, Jongbloed RJ, Hendrickx ATM, de Coo IFM, Smeets HJM. Defective complex I assembly due to C20orf7 mutations as a new cause of Leigh syndrome. J Med Genet 2009; 47:507-12. [PMID: 19542079 PMCID: PMC2921275 DOI: 10.1136/jmg.2009.067553] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Leigh syndrome is an early onset, progressive, neurodegenerative disorder with developmental and motor skills regression. Characteristic magnetic resonance imaging abnormalities consist of focal bilateral lesions in the basal ganglia and/or the brainstem. The main cause is a deficiency in oxidative phosphorylation due to mutations in an mtDNA or nuclear oxidative phosphorylation gene. METHODS AND RESULTS A consanguineous Moroccan family with Leigh syndrome comprise 11 children, three of which are affected. Marker analysis revealed a homozygous region of 11.5 Mb on chromosome 20, containing 111 genes. Eight possible mitochondrial candidate genes were sequenced. Patients were homozygous for an unclassified variant (p.P193L) in the cardiolipin synthase gene (CRLS1). As this variant was present in 20% of a Moroccan control population and enzyme activity was only reduced to 50%, this could not explain the rare clinical phenotype in our family. Patients were also homozygous for an amino acid substitution (p.L159F) in C20orf7, a new complex I assembly factor. Parents were heterozygous and unaffected sibs heterozygous or homozygous wild type. The mutation affects the predicted S-adenosylmethionine (SAM) dependent methyltransferase domain of C20orf7, possibly involved in methylation of NDUFB3 during the assembly process. Blue native gel electrophoresis showed an altered complex I assembly with only 30-40% of mature complex I present in patients and 70-90% in carriers. CONCLUSIONS A new cause of Leigh syndrome can be a defect in early complex I assembly due to C20orf7 mutations.
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Affiliation(s)
- M Gerards
- Department of Genetics and Cell Biology, Unit Clinical Genomics, Maastricht University, Maastricht, The Netherlands
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Zhu X, Peng X, Guan MX, Yan Q. Pathogenic mutations of nuclear genes associated with mitochondrial disorders. Acta Biochim Biophys Sin (Shanghai) 2009; 41:179-87. [PMID: 19280056 DOI: 10.1093/abbs/gmn021] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mitochondrial disorders are clinical phenotypes associated with mitochondrial dysfunction, which can be caused by mutations in mitochondrial DNA (mtDNA) or nuclear genes. In this review, we summarized the pathogenic mutations of nuclear genes associated with mitochondrial disorders. These nuclear genes encode, components of mitochondrial translational machinery and structural subunits and assembly factors of the oxidative phosphorylation, that complex. The molecular mechanisms, that nuclear modifier genes modulate the phenotypic expression of mtDNA mutations, are discussed in detail.
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Affiliation(s)
- Xiaoyu Zhu
- College of Life Science, Zhejiang University, Hangzhou 310058, Peopleos Republic of China
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Unsal E, Aktaş Y, Uner O, BaltacI A, Ozcan S, Turhan F, Baltaci V. Successful application of preimplantation genetic diagnosis for Leigh syndrome. Fertil Steril 2008; 90:2017.e11-3. [PMID: 18778816 DOI: 10.1016/j.fertnstert.2008.07.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 06/09/2008] [Accepted: 07/09/2008] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To perform preimplantation genetic diagnosis (PGD) for a SURF1 gene mutation of the Leigh syndrome to transfer unaffected or carrier embryo/embryos. DESIGN Case report. SETTING Clinical IVF laboratory. PATIENT(S) A couple carrying an nt769 G/A mutation that is associated with Leigh syndrome. INTERVENTION(S) Oocytes were fertilized by means of intracytoplasmic sperm injection. The resulting embryos were biopsied 3 days after fertilization. One blastomere was taken and whole-genome amplification was performed. Amplification of the mutation site was achieved by polymerase chain reaction (PCR) and restriction digestion was completed. Gel Imager was used to measure the digests of normal and mutant load. MAIN OUTCOME MEASURE(S) Embryo testing by means of PGD-PCR and pregnancy. Successful preimplantation genetic diagnosis for a SURF1 gene mutation and transfer of healthy or carrier embryos. RESULT(S) Successful singleton pregnancy resulting in the delivery of healthy baby girl. CONCLUSION(S) We report the first case of successful PGD for Leigh syndrome resulting in delivery of a healthy newborn.
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Affiliation(s)
- Evrim Unsal
- Gen Art Woman Health and Reproductive Biotechnology Center, Ufuk University, Ankara, Turkey.
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40
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Assembly of the oxidative phosphorylation system in humans: what we have learned by studying its defects. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1793:200-11. [PMID: 18620006 DOI: 10.1016/j.bbamcr.2008.05.028] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Revised: 05/12/2008] [Accepted: 05/17/2008] [Indexed: 02/07/2023]
Abstract
Assembly of the oxidative phosphorylation (OXPHOS) system in the mitochondrial inner membrane is an intricate process in which many factors must interact. The OXPHOS system is composed of four respiratory chain complexes, which are responsible for electron transport and generation of the proton gradient in the mitochondrial intermembrane space, and of the ATP synthase that uses this proton gradient to produce ATP. Mitochondrial human disorders are caused by dysfunction of the OXPHOS system, and many of them are associated with altered assembly of one or more components of the OXPHOS system. The study of assembly defects in patients has been useful in unraveling and/or gaining a complete understanding of the processes by which these large multimeric complexes are formed. We review here current knowledge of the biogenesis of OXPHOS complexes based on investigation of the corresponding disorders.
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41
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Jaluria P, Betenbaugh M, Konstantopoulos K, Shiloach J. Enhancement of cell proliferation in various mammalian cell lines by gene insertion of a cyclin-dependent kinase homolog. BMC Biotechnol 2007; 7:71. [PMID: 17945021 PMCID: PMC2164945 DOI: 10.1186/1472-6750-7-71] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2007] [Accepted: 10/18/2007] [Indexed: 12/01/2022] Open
Abstract
Background Genomics tools, particularly DNA microarrays, have found application in a number of areas including gene discovery and disease characterization. Despite the vast utility of these tools, little work has been done to explore the basis of distinct cellular properties, especially those important to biotechnology such as growth. And so, with the intent of engineering cell lines by manipulating the expression of these genes, anchorage-independent and anchorage-dependent HeLa cells, displaying markedly different growth characteristics, were analyzed using DNA microarrays. Results Two genes, cyclin-dependent kinase like 3 (cdkl3) and cytochrome c oxidase subunit (cox15), were up-regulated in the faster growing, anchorage-independent (suspension) HeLa cells relative to the slower growing, anchorage-dependent (attached) HeLa cells. Enhanced expression of either gene in the attached HeLa cells resulted in elevated cell proliferation, though insertion of cdkl3 had a greater impact than that of cox15. Moreover, flow cytometric analysis indicated that cells with an insert of cdkl3 were able to transition from the G0/G1 phases to the S phase faster than control cells. In turn, expression of cox15 was seen to increase the maximum viable cell numbers achieved relative to the control, and to a greater extent than cdkl3. Quantitatively similar results were obtained with two Human Embryonic Kidney-293 (HEK-293) cell lines and a Chinese Hamster Ovary (CHO) cell line. Additionally, HEK-293 cells secreting adipocyte complement-related protein of 30 kDa (acrp30) exhibited a slight increase in specific protein production and higher total protein production in response to the insertion of either cdkl3 or cox15. Conclusion These results are consistent with previous studies on the functionalities of cdkl3 and cox15. For instance, the effect of cdkl3 on cell growth is consistent with its homology to the cdk3 gene which is involved in G1 to S phase transition. Likewise, the increase in cell viability due to cox15 expression is consistent with its role in oxidative phosphorylation as an assembly factor for cytochrome c oxidase and its involvement removing apoptosis-inducing oxygen radicals. Collectively, the present study illustrates the potential of using microarray technology to identify genes influential to specific cellular processes with the possibility of engineering cell lines as desired to meet production needs.
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Affiliation(s)
- Pratik Jaluria
- National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health, Biotechnology Unit, Building 14A, Room 170, Bethesda, MD 20892, USA.
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Oldfors A, Tulinius M. Mitochondrial encephalomyopathies. HANDBOOK OF CLINICAL NEUROLOGY 2007; 86:125-165. [PMID: 18808998 DOI: 10.1016/s0072-9752(07)86006-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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Wick R, Scott G, Byard RW. Mechanisms of unexpected death and autopsy findings in Leigh syndrome (subacute necrotising encephalomyelopathy). J Forensic Leg Med 2006; 14:42-5. [PMID: 16488174 DOI: 10.1016/j.jcfm.2006.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2005] [Revised: 01/01/2006] [Accepted: 01/01/2006] [Indexed: 10/25/2022]
Abstract
A 21-year-old previously-well woman who was undergoing medical investigations for problems with balance and suspected multiple sclerosis, developed a headache and breathing difficulties, and died suddenly and unexpected at home. The autopsy was unremarkable except for pulmonary and cerebral oedema. However, subsequent microscopy of the brain revealed characteristic features of Leigh syndrome with multifocal areas of astrogliosis, capillary proliferation, and parenchymal vacuolation. While Leigh syndrome is more commonly diagnosed in infancy, manifestations may occur throughout early life into adulthood. Sudden and unexpected death is a rare presentation that may be associated with cerebral necrosis and oedema. An awareness of the variable manifestations of Leigh syndrome is necessary in forensic practice as not all cases will present in a typical manner and sudden death may occur before a diagnosis has been established. The heritable nature of this condition makes accuracy of diagnosis essential.
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Affiliation(s)
- Regula Wick
- Forensic Science SA, 21 Divett Place, Adelaide, SA 5000, Australia
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Gui J, Li H. Penalized Cox regression analysis in the high-dimensional and low-sample size settings, with applications to microarray gene expression data. Bioinformatics 2005; 21:3001-8. [PMID: 15814556 DOI: 10.1093/bioinformatics/bti422] [Citation(s) in RCA: 339] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
MOTIVATION An important application of microarray technology is to relate gene expression profiles to various clinical phenotypes of patients. Success has been demonstrated in molecular classification of cancer in which the gene expression data serve as predictors and different types of cancer serve as a categorical outcome variable. However, there has been less research in linking gene expression profiles to the censored survival data such as patients' overall survival time or time to cancer relapse. It would be desirable to have models with good prediction accuracy and parsimony property. RESULTS We propose to use the L(1) penalized estimation for the Cox model to select genes that are relevant to patients' survival and to build a predictive model for future prediction. The computational difficulty associated with the estimation in the high-dimensional and low-sample size settings can be efficiently solved by using the recently developed least-angle regression (LARS) method. Our simulation studies and application to real datasets on predicting survival after chemotherapy for patients with diffuse large B-cell lymphoma demonstrate that the proposed procedure, which we call the LARS-Cox procedure, can be used for identifying important genes that are related to time to death due to cancer and for building a parsimonious model for predicting the survival of future patients. The LARS-Cox regression gives better predictive performance than the L(2) penalized regression and a few other dimension-reduction based methods. CONCLUSIONS We conclude that the proposed LARS-Cox procedure can be very useful in identifying genes relevant to survival phenotypes and in building a parsimonious predictive model that can be used for classifying future patients into clinically relevant high- and low-risk groups based on the gene expression profile and survival times of previous patients.
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MESH Headings
- Biomarkers, Tumor/metabolism
- Computer Simulation
- Diagnosis, Computer-Assisted/methods
- Gene Expression Profiling/methods
- Humans
- Lymphoma, Large B-Cell, Diffuse/diagnosis
- Lymphoma, Large B-Cell, Diffuse/metabolism
- Lymphoma, Large B-Cell, Diffuse/mortality
- Models, Biological
- Models, Statistical
- Neoplasm Proteins/metabolism
- Oligonucleotide Array Sequence Analysis/methods
- Prevalence
- Proportional Hazards Models
- Regression Analysis
- Reproducibility of Results
- Risk Assessment/methods
- Risk Factors
- Sample Size
- Sensitivity and Specificity
- Survival Analysis
- Survival Rate
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Affiliation(s)
- Jiang Gui
- Department of Statistics, University of California Davis, CA 95616, USA
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DiMauro S, Hirano M. Mitochondrial encephalomyopathies: an update. Neuromuscul Disord 2005; 15:276-86. [PMID: 15792866 DOI: 10.1016/j.nmd.2004.12.008] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Revised: 12/10/2004] [Accepted: 12/10/2004] [Indexed: 01/10/2023]
Abstract
A genetic classification of the mitochondrial encephalomyopathies includes disorders due to defects of mitochondrial DNA (mtDNA) and disorders due to defects of nuclear DNA (nDNA). Recent progress in mtDNA-related diseases includes: (i) new pathogenic mutations in protein-coding genes, especially those encoding subunits of complex I (ND genes); (ii) the pathogenic nature of homoplasmic mutations, whose expression is regulated by environmental and genetic factors; (iii) increasing interest in the functional and pathophysiological role of haplotypes. Advances in mendelian mitochondrial diseases include: (i) new mutations in genes for complex I subunits; (ii) identification of new mutant ancillary proteins associated with complex IV and complex V deficiencies; (iii) better molecular understanding of disorders due to faulty intergenomic communication, which are associated with multiple mtDNA deletions, mtDNA depletion, or defects of mtDNA translation; (iv) the pathogenic role of alterations of the inner mitochondrial membrane phospholipid components, especially cardiolipin; (v) the emerging importance of defects in mitochondrial motility, fission, or fusion.
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Affiliation(s)
- Salvatore DiMauro
- Department of Neurology, Columbia University Medical Center, College of Physicians and Surgeons, Room 4-420, 630 West 168th Street, New York, NY 10032, USA.
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