1
|
Armirola-Ricaurte C, Morant L, Adant I, Hamed SA, Pipis M, Efthymiou S, Amor-Barris S, Atkinson D, Van de Vondel L, Tomic A, de Vriendt E, Zuchner S, Ghesquiere B, Hanna M, Houlden H, Lunn MP, Reilly MM, Rasic VM, Jordanova A. Biallelic variants in COX18 cause a mitochondrial disorder primarily manifesting as peripheral neuropathy. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.07.03.24309787. [PMID: 39006432 PMCID: PMC11245062 DOI: 10.1101/2024.07.03.24309787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Defects in mitochondrial dynamics are a common cause of Charcot-Marie-Tooth disease (CMT), while primary deficiencies in the mitochondrial respiratory chain (MRC) are rare and atypical for this etiology. This study aims to report COX18 as a novel CMT-causing gene. This gene encodes an assembly factor of mitochondrial Complex IV (CIV) that translocates the C-terminal tail of MTCO2 across the mitochondrial inner membrane. Exome sequencing was performed in four affected individuals. The patients and available family members underwent thorough neurological and electrophysiological assessment. The impact of one of the identified variants on splicing, protein levels, and mitochondrial bioenergetics was investigated in patient-derived lymphoblasts. The functionality of the mutant protein was assessed using a Proteinase K protection assay and immunoblotting. Neuronal relevance of COX18 was assessed in a Drosophila melanogaster knockdown model. Exome sequencing coupled with homozygosity mapping revealed a homozygous splice variant c.435-6A>G in COX18 in two siblings with early-onset progressive axonal sensory-motor peripheral neuropathy. By querying external databases, we identified two additional families with rare deleterious biallelic variants in COX18 . All affected individuals presented with axonal CMT and some patients also exhibited central nervous system symptoms, such as dystonia and spasticity. Functional characterization of the c.435-6A>G variant demonstrated that it leads to the expression of an alternative transcript that lacks exon 2, resulting in a stable but defective COX18 isoform. The mutant protein impairs CIV assembly and activity, leading to a reduction in mitochondrial membrane potential. Downregulation of the COX18 homolog in Drosophila melanogaster displayed signs of neurodegeneration, including locomotor deficit and progressive axonal degeneration of sensory neurons. Our study presents genetic and functional evidence that supports COX18 as a newly identified gene candidate for autosomal recessive axonal CMT with or without central nervous system involvement. These findings emphasize the significance of peripheral neuropathy within the spectrum of primary mitochondrial disorders and the role of mitochondrial CIV in the development of CMT. Our research has important implications for the diagnostic workup of CMT patients.
Collapse
|
2
|
Povea-Cabello S, Brischigliaro M, Fernández-Vizarra E. Emerging mechanisms in the redox regulation of mitochondrial cytochrome c oxidase assembly and function. Biochem Soc Trans 2024; 52:873-885. [PMID: 38526156 DOI: 10.1042/bst20231183] [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: 01/30/2024] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 03/26/2024]
Abstract
In eukaryotic cells, mitochondria perform cellular respiration through a series of redox reactions ultimately reducing molecular oxygen to water. The system responsible for this process is the respiratory chain or electron transport system (ETS) composed of complexes I-IV. Due to its function, the ETS is the main source of reactive oxygen species (ROS), generating them on both sides of the mitochondrial inner membrane, i.e. the intermembrane space (IMS) and the matrix. A correct balance between ROS generation and scavenging is important for keeping the cellular redox homeostasis and other important aspects of cellular physiology. However, ROS generated in the mitochondria are important signaling molecules regulating mitochondrial biogenesis and function. The IMS contains a large number of redox sensing proteins, containing specific Cys-rich domains, that are involved in ETS complex biogenesis. The large majority of these proteins function as cytochrome c oxidase (COX) assembly factors, mainly for the handling of copper ions necessary for the formation of the redox reactive catalytic centers. A particular case of ROS-regulated COX assembly factor is COA8, whose intramitochondrial levels are increased by oxidative stress, promoting COX assembly and/or protecting the enzyme from oxidative damage. In this review, we will discuss the current knowledge concerning the role played by ROS in regulating mitochondrial activity and biogenesis, focusing on the COX enzyme and with a special emphasis on the functional role exerted by the redox sensitive Cys residues contained in the COX assembly factors.
Collapse
Affiliation(s)
- Suleva Povea-Cabello
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
| | - Michele Brischigliaro
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
| | - Erika Fernández-Vizarra
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
| |
Collapse
|
3
|
Higuchi Y, Ando M, Kojima F, Yuan J, Hashiguchi A, Yoshimura A, Hiramatsu Y, Nozuma S, Fukumura S, Yahikozawa H, Abe E, Toyoshima I, Sugawara M, Okamoto Y, Matsuura E, Takashima H. Dystonia and Parkinsonism in COA7-related disorders: expanding the phenotypic spectrum. J Neurol 2024; 271:419-430. [PMID: 37750949 PMCID: PMC10769979 DOI: 10.1007/s00415-023-11998-3] [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: 07/05/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/27/2023]
Abstract
BACKGROUND AND OBJECTIVE Biallelic mutations in the COA7 gene have been associated with spinocerebellar ataxia with axonal neuropathy type 3 (SCAN3), and a notable clinical diversity has been observed. We aim to identify the genetic and phenotypic spectrum of COA7-related disorders. METHODS We conducted comprehensive genetic analyses on the COA7 gene within a large group of Japanese patients clinically diagnosed with inherited peripheral neuropathy or cerebellar ataxia. RESULTS In addition to our original report, which involved four patients until 2018, we identified biallelic variants of the COA7 gene in another three unrelated patients, and the variants were c.17A > G (p.D6G), c.115C > T (p.R39W), and c.449G > A (p.C150Y; novel). Patient 1 presented with an infantile-onset generalized dystonia without cerebellar ataxia. Despite experiencing an initial transient positive response to levodopa and deep brain stimulation, he became bedridden by the age of 19. Patient 2 presented with cerebellar ataxia, neuropathy, as well as parkinsonism, and showed a slight improvement upon levodopa administration. Dopamine transporter SPECT showed decreased uptake in the bilateral putamen in both patients. Patient 3 exhibited severe muscle weakness, respiratory failure, and feeding difficulties. A haplotype analysis of the mutation hotspot in Japan, c.17A > G (p.D6G), uncovered a common haplotype block. CONCLUSION COA7-related disorders typically encompass a spectrum of conditions characterized by a variety of major (cerebellar ataxia and axonal polyneuropathy) and minor (leukoencephalopathy, dystonia, and parkinsonism) symptoms, but may also display a dystonia-predominant phenotype. We propose that COA7 should be considered as a new causative gene for infancy-onset generalized dystonia, and COA7 gene screening is recommended for patients with unexplained dysfunctions of the central and peripheral nervous systems.
Collapse
Affiliation(s)
- Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Masahiro Ando
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Fumikazu Kojima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Junhui Yuan
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Yu Hiramatsu
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Satoshi Nozuma
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Shinobu Fukumura
- Department of Pediatrics, Sapporo Medical University School of Medicine, Sapporo, Japan
| | | | - Erika Abe
- Department of Neurology, National Hospital Organization Akita National Hospital, Yurihonjo, Japan
| | - Itaru Toyoshima
- Department of Neurology, National Hospital Organization Akita National Hospital, Yurihonjo, Japan
| | - Masashiro Sugawara
- Department of Neurology, Akita University Graduate School of Medicine, Akita, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
- Department of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima, Japan
| | - Eiji Matsuura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima, 890-8520, Japan.
| |
Collapse
|
4
|
Chen S, Wang K, Wang J, Chen X, Tao M, Shan D, Hua X, Hu S, Song J. Profiling cardiomyocytes at single cell resolution reveals COX7B could be a potential target for attenuating heart failure in cardiac hypertrophy. J Mol Cell Cardiol 2024; 186:45-56. [PMID: 37979444 DOI: 10.1016/j.yjmcc.2023.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 11/02/2023] [Accepted: 11/12/2023] [Indexed: 11/20/2023]
Abstract
Cardiac hypertrophy can develop to end-stage heart failure (HF), which inevitably leading to heart transplantation or death. Preserving cardiac function in cardiomyocytes (CMs) is essential for improving prognosis in hypertrophic cardiomyopathy (HCM) patients. Therefore, understanding transcriptomic heterogeneity of CMs in HCM would be indispensable to aid potential therapeutic targets investigation. We isolated primary CM from HCM patients who had extended septal myectomy, and obtained transcriptomes in 338 human primary CM with single-cell tagged reverse transcription (STRT-seq) approach. Our results revealed that CMs could be categorized into three subsets in nonfailing HCM heart: high energy synthesis cluster, high cellular metabolism cluster and intermediate cluster. The expression of electron transport chain (ETC) was up-regulated in larger-sized CMs from high energy synthesis cluster. Of note, we found the expression of Cytochrome c oxidase subunit 7B (COX7B), a subunit of Complex IV in ETC had trends of positively correlation with CMs size. Further, by assessing COX7B expression in HCM patients, we speculated that COX7B was compensatory up-regulated at early-stage but down-regulated in failing HCM heart. To test the hypothesis that COX7B might participate both in hypertrophy and HF progression, we used adeno associated virus 9 (AAV9) to mediate the expression of Cox7b in pressure overload-induced mice. Mice in vivo data supported that knockdown of Cox7b would accelerate HF and Cox7b overexpression could restore partial cardiac function in hypertrophy. Our result highlights targeting COX7B and preserving energy synthesis in hypertrophic CMs could be a promising translational direction for HF therapeutic strategy.
Collapse
Affiliation(s)
- Shi Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Kui Wang
- School of Statistics and Data Science, LPMC and KLMDASR, Nankai University, Tianjin, China
| | - Jingyu Wang
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Xiao Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Menghao Tao
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Dan Shan
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiumeng Hua
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shengshou Hu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
| | - Jiangping Song
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
| |
Collapse
|
5
|
Bhattacharya MRC. A nerve-wracking buzz: lessons from Drosophila models of peripheral neuropathy and axon degeneration. Front Aging Neurosci 2023; 15:1166146. [PMID: 37614471 PMCID: PMC10442544 DOI: 10.3389/fnagi.2023.1166146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 07/24/2023] [Indexed: 08/25/2023] Open
Abstract
The degeneration of axons and their terminals occurs following traumatic, toxic, or genetically-induced insults. Common molecular mechanisms unite these disparate triggers to execute a conserved nerve degeneration cascade. In this review, we will discuss how models of peripheral nerve injury and neuropathy in Drosophila have led the way in advancing molecular understanding of axon degeneration and nerve injury pathways. Both neuron-intrinsic as well as glial responses to injury will be highlighted. Finally, we will offer perspective on what additional questions should be answered to advance these discoveries toward clinical interventions for patients with neuropathy.
Collapse
|
6
|
Ouchi S, Ishii K, Kosaki K, Suzuki H, Yamada M, Takenouchi T, Tamaoka A. Parkinsonism in spinocerebellar ataxia with axonal neuropathy caused by adult-onset COA7 variants: a case report. BMC Neurol 2023; 23:211. [PMID: 37264311 DOI: 10.1186/s12883-023-03202-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 04/05/2023] [Indexed: 06/03/2023] Open
Abstract
BACKGROUND Individuals with variants of cytochrome c oxidase assembly factor 7 (COA7), a mitochondrial functional-related gene, exhibit symptoms of spinocerebellar ataxia with axonal neuropathy before the age of 20. However, COA7 variants with parkinsonism or adult-onset type cases have not been described. CASE PRESENTATION We report the case of a patient who developed cerebellar symptoms and slowly progressive sensory and motor neuropathy in the extremities, similar to Charcot-Marie-Tooth disease, at age 30, followed by parkinsonism at age 58. Exome analysis revealed COA7 missense mutation in homozygotes (NM_023077.2:c.17A > G, NP_075565.2: p.Asp6Gly). Dopamine transporter single-photon emission computed tomography using a 123I-Ioflupane revealed clear hypo-accumulation in the bilateral striatum. However, 123I-metaiodobenzylguanidine myocardial scintigraphy showed normal sympathetic nerve function. Levodopa administration improved parkinsonism in this patient. CONCLUSIONS COA7 gene variants may have caused parkinsonism in this case because mitochondrial function-related genes, such as parkin and PINK1, are known causative genes in some familial Parkinson's diseases.
Collapse
Affiliation(s)
- Shogo Ouchi
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Ten'nudai 1-1-1, Tsukuba, Ibaraki, 305-8575, Japan
| | - Kazuhiro Ishii
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Ten'nudai 1-1-1, Tsukuba, Ibaraki, 305-8575, Japan.
| | - Kenjiro Kosaki
- Center for Medical Genetics, Keio University, 35 Shinanomachi Shinju-Ku, Tokyo, 160-8582, Japan
| | - Hisato Suzuki
- Center for Medical Genetics, Keio University, 35 Shinanomachi Shinju-Ku, Tokyo, 160-8582, Japan
| | - Mamiko Yamada
- Center for Medical Genetics, Keio University, 35 Shinanomachi Shinju-Ku, Tokyo, 160-8582, Japan
| | - Toshiki Takenouchi
- Center for Medical Genetics, Keio University, 35 Shinanomachi Shinju-Ku, Tokyo, 160-8582, Japan
| | - Akira Tamaoka
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Ten'nudai 1-1-1, Tsukuba, Ibaraki, 305-8575, Japan
| |
Collapse
|
7
|
Higuchi Y, Takashima H. Clinical genetics of Charcot-Marie-Tooth disease. J Hum Genet 2023; 68:199-214. [PMID: 35304567 DOI: 10.1038/s10038-022-01031-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/02/2022] [Accepted: 03/06/2022] [Indexed: 02/08/2023]
Abstract
Recent research in the field of inherited peripheral neuropathies (IPNs) such as Charcot-Marie-Tooth (CMT) disease has helped identify the causative genes provided better understanding of the pathogenesis, and unraveled potential novel therapeutic targets. Several reports have described the epidemiology, clinical characteristics, molecular pathogenesis, and novel causative genes for CMT/IPNs in Japan. Based on the functions of the causative genes identified so far, the following molecular and cellular mechanisms are believed to be involved in the causation of CMTs/IPNs: myelin assembly, cytoskeletal structure, myelin-specific transcription factor, nuclear related, endosomal sorting and cell signaling, proteasome and protein aggregation, mitochondria-related, motor proteins and axonal transport, tRNA synthetases and RNA metabolism, and ion channel-related mechanisms. In this article, we review the epidemiology, genetic diagnosis, and clinicogenetic characteristics of CMT in Japan. In addition, we discuss the newly identified novel causative genes for CMT/IPNs in Japan, namely MME and COA7. Identification of the new causes of CMT will facilitate in-depth characterization of the underlying molecular mechanisms of CMT, leading to the establishment of therapeutic approaches such as drug development and gene therapy.
Collapse
Affiliation(s)
- Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
| |
Collapse
|
8
|
Brischigliaro M, Fernandez-Vizarra E, Viscomi C. Mitochondrial Neurodegeneration: Lessons from Drosophila melanogaster Models. Biomolecules 2023; 13:378. [PMID: 36830747 PMCID: PMC9953451 DOI: 10.3390/biom13020378] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 02/09/2023] [Accepted: 02/13/2023] [Indexed: 02/19/2023] Open
Abstract
The fruit fly-i.e., Drosophila melanogaster-has proven to be a very useful model for the understanding of basic physiological processes, such as development or ageing. The availability of straightforward genetic tools that can be used to produce engineered individuals makes this model extremely interesting for the understanding of the mechanisms underlying genetic diseases in physiological models. Mitochondrial diseases are a group of yet-incurable genetic disorders characterized by the malfunction of the oxidative phosphorylation system (OXPHOS), which is the highly conserved energy transformation system present in mitochondria. The generation of D. melanogaster models of mitochondrial disease started relatively recently but has already provided relevant information about the molecular mechanisms and pathological consequences of mitochondrial dysfunction. Here, we provide an overview of such models and highlight the relevance of D. melanogaster as a model to study mitochondrial disorders.
Collapse
Affiliation(s)
- Michele Brischigliaro
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
| | - Erika Fernandez-Vizarra
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
| | - Carlo Viscomi
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
- Centre for the Study of Neurodegeneration (CESNE), University of Padova, 35131 Padova, Italy
| |
Collapse
|
9
|
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: 14] [Impact Index Per Article: 7.0] [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.
Collapse
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
| |
Collapse
|
10
|
Lange LM, Gonzalez-Latapi P, Rajalingam R, Tijssen MAJ, Ebrahimi-Fakhari D, Gabbert C, Ganos C, Ghosh R, Kumar KR, Lang AE, Rossi M, van der Veen S, van de Warrenburg B, Warner T, Lohmann K, Klein C, Marras C. Nomenclature of Genetic Movement Disorders: Recommendations of the International Parkinson and Movement Disorder Society Task Force - An Update. Mov Disord 2022; 37:905-935. [PMID: 35481685 DOI: 10.1002/mds.28982] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/28/2022] [Accepted: 02/14/2022] [Indexed: 12/13/2022] Open
Abstract
In 2016, the Movement Disorder Society Task Force for the Nomenclature of Genetic Movement Disorders presented a new system for naming genetically determined movement disorders and provided a criterion-based list of confirmed monogenic movement disorders. Since then, a substantial number of novel disease-causing genes have been described, which warrant classification using this system. In addition, with this update, we further refined the system and propose dissolving the imaging-based categories of Primary Familial Brain Calcification and Neurodegeneration with Brain Iron Accumulation and reclassifying these genetic conditions according to their predominant phenotype. We also introduce the novel category of Mixed Movement Disorders (MxMD), which includes conditions linked to multiple equally prominent movement disorder phenotypes. In this article, we present updated lists of newly confirmed monogenic causes of movement disorders. We found a total of 89 different newly identified genes that warrant a prefix based on our criteria; 6 genes for parkinsonism, 21 for dystonia, 38 for dominant and recessive ataxia, 5 for chorea, 7 for myoclonus, 13 for spastic paraplegia, 3 for paroxysmal movement disorders, and 6 for mixed movement disorder phenotypes; 10 genes were linked to combined phenotypes and have been assigned two new prefixes. The updated lists represent a resource for clinicians and researchers alike and they have also been published on the website of the Task Force for the Nomenclature of Genetic Movement Disorders on the homepage of the International Parkinson and Movement Disorder Society (https://www.movementdisorders.org/MDS/About/Committees--Other-Groups/MDS-Task-Forces/Task-Force-on-Nomenclature-in-Movement-Disorders.htm). © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.
Collapse
Affiliation(s)
- Lara M Lange
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Paulina Gonzalez-Latapi
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada.,Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Rajasumi Rajalingam
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Marina A J Tijssen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Darius Ebrahimi-Fakhari
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Carolin Gabbert
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christos Ganos
- Department of Neurology, Charité University Hospital Berlin, Berlin, Germany
| | - Rhia Ghosh
- Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Kishore R Kumar
- Molecular Medicine Laboratory and Department of Neurology, Concord Repatriation General Hospital, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Anthony E Lang
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Malco Rossi
- Movement Disorders Section, Neuroscience Department, Raul Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina
| | - Sterre van der Veen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Bart van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Center of Expertise for Parkinson and Movement Disorders, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tom Warner
- Department of Clinical & Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Katja Lohmann
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Connie Marras
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | | |
Collapse
|
11
|
Complex hereditary peripheral neuropathies caused by novel variants in mitochondrial-related nuclear genes. J Neurol 2022; 269:4129-4140. [PMID: 35235001 PMCID: PMC9293870 DOI: 10.1007/s00415-022-11026-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/05/2022] [Accepted: 02/11/2022] [Indexed: 11/04/2022]
Abstract
Mitochondrial disorders are a group of clinically and genetically heterogeneous multisystem disorders and peripheral neuropathy is frequently described in the context of mutations in mitochondrial-related nuclear genes. This study aimed to identify the causative mutations in mitochondrial-related nuclear genes in suspected hereditary peripheral neuropathy patients. We enrolled a large Japanese cohort of clinically suspected hereditary peripheral neuropathy patients who were mutation negative in the prescreening of the known Charcot–Marie–Tooth disease-causing genes. We performed whole-exome sequencing on 247 patients with autosomal recessive or sporadic inheritance for further analysis of 167 mitochondrial-related nuclear genes. We detected novel bi-allelic likely pathogenic/pathogenic variants in four patients, from four mitochondrial-related nuclear genes: pyruvate dehydrogenase beta-polypeptide (PDHB), mitochondrial poly(A) polymerase (MTPAP), hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase, beta subunit (HADHB), and succinate-CoA ligase ADP-forming beta subunit (SUCLA2). All these patients showed sensory and motor axonal polyneuropathy, combined with central nervous system or multisystem involvements. The pathological analysis of skeletal muscles revealed mild neurogenic changes without significant mitochondrial abnormalities. Targeted screening of mitochondria-related nuclear genes should be considered for patients with complex hereditary axonal polyneuropathy, accompanied by central nervous system dysfunctions, or with unexplainable multisystem disorders.
Collapse
|
12
|
Mitochondrial COA7 is a heme-binding protein with disulfide reductase activity, which acts in the early stages of complex IV assembly. Proc Natl Acad Sci U S A 2022; 119:2110357119. [PMID: 35210360 PMCID: PMC8892353 DOI: 10.1073/pnas.2110357119] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2022] [Indexed: 12/12/2022] Open
Abstract
Assembly factors play key roles in the biogenesis of mitochondrial protein complexes, regulating their stabilities, activities, and incorporation of essential cofactors. Cytochrome c oxidase assembly factor 7 (COA7) is a metazoan-specific assembly factor, the absence or mutation of which in humans accompanies complex IV assembly defects and neurological conditions. Here, we report the crystal structure of COA7 to 2.4 Å resolution, revealing a banana-shaped molecule composed of five helix-turn-helix (α/α) repeats. COA7 binds heme with micromolar affinity, even though the protein structure does not resemble previously characterized heme-binding proteins. The heme-bound COA7 can redox cycle between oxidation states Fe(II) and Fe(III) and shows disulfide reductase activity toward copper binding assembly factors. We propose that COA7 functions to facilitate the biogenesis of the binuclear copper site (CuA) of complex IV. Cytochrome c oxidase (COX) assembly factor 7 (COA7) is a metazoan-specific assembly factor, critical for the biogenesis of mitochondrial complex IV (cytochrome c oxidase). Although mutations in COA7 have been linked to complex IV assembly defects and neurological conditions such as peripheral neuropathy, ataxia, and leukoencephalopathy, the precise role COA7 plays in the biogenesis of complex IV is not known. Here, we show that loss of COA7 blocks complex IV assembly after the initial step where the COX1 module is built, progression from which requires the incorporation of copper and addition of the COX2 and COX3 modules. The crystal structure of COA7, determined to 2.4 Å resolution, reveals a banana-shaped molecule composed of five helix-turn-helix (α/α) repeats, tethered by disulfide bonds. COA7 interacts transiently with the copper metallochaperones SCO1 and SCO2 and catalyzes the reduction of disulfide bonds within these proteins, which are crucial for copper relay to COX2. COA7 binds heme with micromolar affinity, through axial ligation to the central iron atom by histidine and methionine residues. We therefore propose that COA7 is a heme-binding disulfide reductase for regenerating the copper relay system that underpins complex IV assembly.
Collapse
|
13
|
Corral-Juan M, Casquero P, Giraldo-Restrepo N, Laurie S, Martinez-Piñeiro A, Mateo-Montero RC, Ispierto L, Vilas D, Tolosa E, Volpini V, Alvarez-Ramo R, Sánchez I, Matilla-Dueñas A. OUP accepted manuscript. Brain Commun 2022; 4:fcac030. [PMID: 35310830 PMCID: PMC8928420 DOI: 10.1093/braincomms/fcac030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/20/2021] [Accepted: 02/08/2022] [Indexed: 11/18/2022] Open
Abstract
Spinocerebellar ataxias consist of a highly heterogeneous group of inherited movement disorders clinically characterized by progressive cerebellar ataxia variably associated with additional distinctive clinical signs. The genetic heterogeneity is evidenced by the myriad of associated genes and underlying genetic defects identified. In this study, we describe a new spinocerebellar ataxia subtype in nine members of a Spanish five-generation family from Menorca with affected individuals variably presenting with ataxia, nystagmus, dysarthria, polyneuropathy, pyramidal signs, cerebellar atrophy and distinctive cerebral demyelination. Affected individuals presented with horizontal and vertical gaze-evoked nystagmus and hyperreflexia as initial clinical signs, and a variable age of onset ranging from 12 to 60 years. Neurophysiological studies showed moderate axonal sensory polyneuropathy with altered sympathetic skin response predominantly in the lower limbs. We identified the c.1877C > T (p.Ser626Leu) pathogenic variant within the SAMD9L gene as the disease causative genetic defect with a significant log-odds score (Zmax = 3.43; θ = 0.00; P < 3.53 × 10−5). We demonstrate the mitochondrial location of human SAMD9L protein, and its decreased levels in patients’ fibroblasts in addition to mitochondrial perturbations. Furthermore, mutant SAMD9L in zebrafish impaired mobility and vestibular/sensory functions. This study describes a novel spinocerebellar ataxia subtype caused by SAMD9L mutation, SCA49, which triggers mitochondrial alterations pointing to a role of SAMD9L in neurological motor and sensory functions.
Collapse
Affiliation(s)
- Marc Corral-Juan
- Functional and Translational Neurogenetics Unit, Department of Neuroscience, Research Institute Germans Trias i Pujol (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | - Pilar Casquero
- Neurology and Neurophysiology Section, Hospital Mateu Orfila, Mahón, Menorca, Spain
| | | | - Steve Laurie
- Centro Nacional de Análisis Genómico (CNAG-CRG), Center for Genomic Regulation, Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Alicia Martinez-Piñeiro
- Neuromuscular and Functional Studies Unit, Neurology Service, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | | | - Lourdes Ispierto
- Neurodegenerative Diseases Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | - Dolores Vilas
- Neurodegenerative Diseases Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
- Parkinson Disease and Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona (UB), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED: CB06/05/0018-ISCIII), Barcelona, Spain
| | - Eduardo Tolosa
- Parkinson Disease and Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona (UB), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED: CB06/05/0018-ISCIII), Barcelona, Spain
| | | | - Ramiro Alvarez-Ramo
- Neurodegenerative Diseases Unit, Neurology Service, Department of Neuroscience, University Hospital Germans Trias i Pujol (HUGTiP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | - Ivelisse Sánchez
- Functional and Translational Neurogenetics Unit, Department of Neuroscience, Research Institute Germans Trias i Pujol (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
| | - Antoni Matilla-Dueñas
- Functional and Translational Neurogenetics Unit, Department of Neuroscience, Research Institute Germans Trias i Pujol (IGTP), Universitat Autònoma de Barcelona-Can Ruti Campus, Badalona, Barcelona, Spain
- Correspondence to: Dr Antoni Matilla-Dueñas Head of the Neurogenetics Unit Health Sciences Research Institute Germans Trias i Pujol (IGTP) Ctra. de Can Ruti, Camí de les Escoles s/n 08916 Badalona, Barcelona, Spain E-mail:
| |
Collapse
|
14
|
Lee GS, Kwak G, Bae JH, Han JP, Nam SH, Lee JH, Song S, Kim GD, Park TS, Choi YK, Choi BO, Yeom SC. Morc2a p.S87L mutant mice develop peripheral and central neuropathies associated with neuronal DNA damage and apoptosis. Dis Model Mech 2021; 14:dmm049123. [PMID: 34695197 PMCID: PMC8560500 DOI: 10.1242/dmm.049123] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 09/06/2021] [Indexed: 01/07/2023] Open
Abstract
The microrchidia (MORC)-family CW-type zinc finger 2 (MORC2) gene is related to DNA repair, adipogenesis and epigenetic silencing via the human silencing hub (HUSH) complex. MORC2 missense mutation is known to cause peripheral neuropathy of Charcot-Marie-Tooth disease type 2 Z (CMT2Z). However, there have been reports of peripheral and central neuropathy in patients, and the disease has been co-categorized with developmental delay, impaired growth, dysmorphic facies and axonal neuropathy (DIGFAN). The etiology of MORC2 mutation-mediated neuropathy remains uncertain. Here, we established and analyzed Morc2a p.S87L mutant mice. Morc2a p.S87L mice displayed the clinical symptoms expected in human CMT2Z patients, such as axonal neuropathy and skeletal muscle weakness. Notably, we observed severe central neuropathy with cerebella ataxia, cognition disorder and motor neuron degeneration in the spinal cord, and this seemed to be evidence of DIGFAN. Morc2a p.S87L mice exhibited an accumulation of DNA damage in neuronal cells, followed by p53/cytochrome c/caspase 9/caspase 3-mediated apoptosis. This study presents a new mouse model of CMT2Z and DIGFAN with a Morc2a p.S87L mutation. We suggest that neuronal apoptosis is a possible target for therapeutic approach in MORC2 missense mutation. This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Geon Seong Lee
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
| | - Geon Kwak
- Department of Neurology, Sungkyunkwan University School of Medicine, 81 Irwonr-ro, Gangnam, Seoul 06351, South Korea
- Department of Health Science and Technology, SAIHST, Sungkyunkwan University School of Medicine, 81 Irwonr-ro, Gangnam, Seoul 06351, South Korea
| | - Ji Hyun Bae
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
| | - Jeong Pil Han
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
| | - Soo Hyun Nam
- Department of Neurology, Sungkyunkwan University School of Medicine, 81 Irwonr-ro, Gangnam, Seoul 06351, South Korea
| | - Jeong Hyeon Lee
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
| | - Sumin Song
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
| | - Gap-Don Kim
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
| | - Tae Sub Park
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
| | - Yang Kyu Choi
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, 120 Nueungdong-ro, Gwangjin, Seoul 05029, South Korea
| | - Byung-Ok Choi
- Department of Neurology, Sungkyunkwan University School of Medicine, 81 Irwonr-ro, Gangnam, Seoul 06351, South Korea
- Department of Health Science and Technology, SAIHST, Sungkyunkwan University School of Medicine, 81 Irwonr-ro, Gangnam, Seoul 06351, South Korea
- Stem Cell and Regenerative Medicine Institute, Samgsung Medical Center, Seoul 06351, South Korea
| | - Su Cheong Yeom
- Graduate School of International Agricultural Technology and Institute of Green Bio Science and Technology, Seoul National University, 1447 Pyeongchang-Ro, Daewha, Pyeongchang, Kangwon 25354, South Korea
- WCU Biomodulation Major, Department of Agricultural Biotechnology, Seoul National University, 1 Gwanak-ro, Gwanank, Seoul 08826, South Korea
| |
Collapse
|
15
|
Kitani-Morii F, Friedland RP, Yoshida H, Mizuno T. Drosophila as a Model for Microbiota Studies of Neurodegeneration. J Alzheimers Dis 2021; 84:479-490. [PMID: 34569965 PMCID: PMC8673522 DOI: 10.3233/jad-215031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Accumulating evidence show that the gut microbiota is deeply involved not only in host nutrient metabolism but also in immune function, endocrine regulation, and chronic disease. In neurodegenerative conditions such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis, the gut-brain axis, the bidirectional interaction between the brain and the gut, provides new route of pathological spread and potential therapeutic targets. Although studies of gut microbiota have been conducted mainly in mice, mammalian gut microbiota is highly diverse, complex, and sensitive to environmental changes. Drosophila melanogaster, a fruit fly, has many advantages as a laboratory animal: short life cycle, numerous and genetically homogenous offspring, less ethical concerns, availability of many genetic models, and low maintenance costs. Drosophila has a simpler gut microbiota than mammals and can be made to remain sterile or to have standardized gut microbiota by simple established methods. Research on the microbiota of Drosophila has revealed new molecules that regulate the brain-gut axis, and it has been shown that dysbiosis of the fly microbiota worsens lifespan, motor function, and neurodegeneration in AD and PD models. The results shown in fly studies represents a fundamental part of the immune and proteomic process involving gut-microbiota interactions that are highly conserved. Even though the fly’s gut microbiota are not simple mimics of humans, flies are a valuable system to learn the molecular mechanisms of how the gut microbiota affect host health and behavior.
Collapse
Affiliation(s)
- Fukiko Kitani-Morii
- Department of Molecular Pathobiology of Brain Diseases, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, Japan.,Department of Neurology, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, Japan
| | - Robert P Friedland
- Department of Neurology, University of Louisville School of Medicine, Louisville, KY, USA
| | - Hideki Yoshida
- Applied Biology, Kyoto Institute of Technology, Sakyo-ku, Kyoto, Japan
| | - Toshiki Mizuno
- Department of Neurology, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, Japan
| |
Collapse
|
16
|
Geldon S, Fernández-Vizarra E, Tokatlidis K. Redox-Mediated Regulation of Mitochondrial Biogenesis, Dynamics, and Respiratory Chain Assembly in Yeast and Human Cells. Front Cell Dev Biol 2021; 9:720656. [PMID: 34557489 PMCID: PMC8452992 DOI: 10.3389/fcell.2021.720656] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 08/04/2021] [Indexed: 12/24/2022] Open
Abstract
Mitochondria are double-membrane organelles that contain their own genome, the mitochondrial DNA (mtDNA), and reminiscent of its endosymbiotic origin. Mitochondria are responsible for cellular respiration via the function of the electron oxidative phosphorylation system (OXPHOS), located in the mitochondrial inner membrane and composed of the four electron transport chain (ETC) enzymes (complexes I-IV), and the ATP synthase (complex V). Even though the mtDNA encodes essential OXPHOS components, the large majority of the structural subunits and additional biogenetical factors (more than seventy proteins) are encoded in the nucleus and translated in the cytoplasm. To incorporate these proteins and the rest of the mitochondrial proteome, mitochondria have evolved varied, and sophisticated import machineries that specifically target proteins to the different compartments defined by the two membranes. The intermembrane space (IMS) contains a high number of cysteine-rich proteins, which are mostly imported via the MIA40 oxidative folding system, dependent on the reduction, and oxidation of key Cys residues. Several of these proteins are structural components or assembly factors necessary for the correct maturation and function of the ETC complexes. Interestingly, many of these proteins are involved in the metalation of the active redox centers of complex IV, the terminal oxidase of the mitochondrial ETC. Due to their function in oxygen reduction, mitochondria are the main generators of reactive oxygen species (ROS), on both sides of the inner membrane, i.e., in the matrix and the IMS. ROS generation is important due to their role as signaling molecules, but an excessive production is detrimental due to unwanted oxidation reactions that impact on the function of different types of biomolecules contained in mitochondria. Therefore, the maintenance of the redox balance in the IMS is essential for mitochondrial function. In this review, we will discuss the role that redox regulation plays in the maintenance of IMS homeostasis as well as how mitochondrial ROS generation may be a key regulatory factor for ETC biogenesis, especially for complex IV.
Collapse
Affiliation(s)
| | - Erika Fernández-Vizarra
- Institute of Molecular Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Kostas Tokatlidis
- Institute of Molecular Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
17
|
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.
Collapse
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;
| |
Collapse
|
18
|
Ban R, Liu Z, Shimura M, Tong X, Wang J, Yang L, Xu M, Xiao J, Murayama K, Elstner M, Prokisch H, Fang F. Biallelic COA7-Variants Leading to Developmental Regression With Progressive Spasticity and Brain Atrophy in a Chinese Patient. Front Genet 2021; 12:685035. [PMID: 34322155 PMCID: PMC8312223 DOI: 10.3389/fgene.2021.685035] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/15/2021] [Indexed: 11/13/2022] Open
Abstract
Objective The cytochrome c oxidase assembly factor 7 (COA7) gene encodes a protein localized to mitochondria that is involved in the assembly of mitochondrial respiratory chain complex IV. Here, we report the clinical, genetic and biochemical analysis of a female patient with suspected mitochondrial disorder and novel variants in COA7, that presented with a considerably different phenotype and age of onset than the five COA7 patients reported to date. Methods We performed trio-exome sequencing in the affected patient and both parents. To verify the pathogenicity of the detected variants in COA7, mitochondrial enzyme activities and oxygen consumption rate were investigated in fibroblasts of the patient and her parents. Results A Chinese girl was referred at 9 months of age with a history of developmental delay and regression since 3 months of age. In the following months, she lost previously acquired skills and developed progressive spasticity of the lower extremities. Trio-exome sequencing revealed compound heterzygous variants in COA7 (c.511G > A/p.Ala171Thr and c.566A > G/p.Asn189Ser). Functional validation experiments revealed isolated complex IV deficiency and a significantly reduced mitochondrial respiration rate in patient-derived fibroblasts. Interpretation Hitherto, characteristic features of COA7 patients were described as slowly progressing neuropathy and spinocerebellar ataxia, starting at the toddler age and progressing into adulthood. In contrast, our patient was reported to show developmental delay from 3 months of age, which was found to be due to a rapidly progressive encephalopathy and brain atrophy seen at 9 months of age. Unexpectedly, the genetic investigation revealed a COA7-associated mitochondrial disease, which was confirmed functionally. Thus, this report broadens the genetic and clinical spectrum of this heterogeneous mitochondriopathy and highlights the value of the presented unbiased approach.
Collapse
Affiliation(s)
- Rui Ban
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China.,Institute of Human Genetics, Helmholtz Zentrum München, Munich, Germany
| | - Zhimei Liu
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Masaru Shimura
- Institute of Human Genetics, Helmholtz Zentrum München, Munich, Germany.,Department of Metabolism, Chiba Children's Hospital, Chiba, Japan
| | - Xiao Tong
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Junling Wang
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Lei Yang
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Manting Xu
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Jing Xiao
- Department of Neurology, Beijing New Century International Children's Hospital, Beijing China
| | - Kei Murayama
- Department of Metabolism, Chiba Children's Hospital, Chiba, Japan
| | - Matthias Elstner
- Department of Neurology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Holger Prokisch
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China.,Institute of Human Genetics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - Fang Fang
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| |
Collapse
|
19
|
Yamaguchi M, Lee IS, Jantrapirom S, Suda K, Yoshida H. Drosophila models to study causative genes for human rare intractable neurological diseases. Exp Cell Res 2021; 403:112584. [PMID: 33812867 DOI: 10.1016/j.yexcr.2021.112584] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/25/2021] [Accepted: 03/27/2021] [Indexed: 12/11/2022]
Abstract
Drosophila is emerging as a convenient model for investigating human diseases. Functional homologues of almost 75% of human disease-related genes are found in Drosophila. Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease that causes defects in motoneurons. Charcot-Marie-Tooth disease (CMT) is one of the most commonly found inherited neuropathies affecting both motor and sensory neurons. No effective therapy has been established for either of these diseases. In this review, after overviewing ALS, Drosophila models targeting several ALS-causing genes, including TDP-43, FUS and Ubiquilin2, are described with their genetic interactants. Then, after overviewing CMT, examples of Drosophila models targeting several CMT-causing genes, including mitochondria-related genes and FIG 4, are also described with their genetic interactants. In addition, we introduce Sotos syndrome caused by mutations in the epigenetic regulator gene NSD1. Lastly, several genes and pathways that commonly interact with ALS- and/or CMT-causing genes are described. In the case of ALS and CMT that have many causative genes, it may be not practical to perform gene therapy for each of the many disease-causing genes. The possible uses of the common genes and pathways as novel diagnosis markers and effective therapeutic targets are discussed.
Collapse
Affiliation(s)
- Masamitsu Yamaguchi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan; Kansai Gakken Laboratory, Kankyo Eisei Yakuhin Co. Ltd., Seika-cho, Kyoto, 619-0237, Japan
| | - Im-Soon Lee
- Department of Biological Sciences, Konkuk University, Seoul, Republic of Korea
| | - Salinee Jantrapirom
- Department of Pharmacology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kojiro Suda
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Hideki Yoshida
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
| |
Collapse
|
20
|
Dong HL, Ma Y, Yu H, Wei Q, Li JQ, Liu GL, Li HF, Chen L, Chen DF, Bai G, Wu ZY. Bi-allelic loss of function variants in COX20 gene cause autosomal recessive sensory neuronopathy. Brain 2021; 144:2457-2470. [PMID: 33751098 DOI: 10.1093/brain/awab135] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 01/18/2021] [Accepted: 01/30/2021] [Indexed: 12/24/2022] Open
Abstract
Sensory neuronopathies are a rare and distinct subgroup of peripheral neuropathies, characterized by degeneration of the dorsal root ganglia neurons. About 50% of sensory neuronopathies are idiopathic and genetic causes remain to be clarified. Through a combination of homozygosity mapping and whole exome sequencing, we linked an autosomal recessive sensory neuronopathy to pathogenic variants in COX20 gene. We identified 8 unrelated families from the eastern China population carrying a founder variant c.41A>G (p. Lys14Arg) within COX20 in either a homozygous or compound heterozygous state. All patients displayed sensory ataxia with non-length-dependent sensory potentials decrease. COX20 encodes a key transmembrane protein implicated in the assembly of mitochondrial complex IV. We showed that COX20 variants lead to reduction of COX20 protein in patient's fibroblasts and transfected cell lines, consistent with a loss-of-function mechanism. Knockdown of COX20 expression in ND7/23 sensory neuron cells resulted in complex IV deficiency and perturbed assembly of complex IV, which subsequently compromised cell spare respiratory capacity and reduced cell proliferation under metabolic stress. Consistent with mitochondrial dysfunction in knockdown cells, reduced complex IV assembly, enzyme activity and oxygen consumption rate were also found in patients' fibroblasts. We speculated that the mechanism of COX20 was similar to other causative genes (e.g. SURF1, COX6A1, COA3 and SCO2) for peripheral neuropathies, all of which were functionally important in the structure and assembly of complex IV. Our study identifies a novel causative gene for the autosomal recessive sensory neuronopathy, whose vital function in complex IV and high expression in the proprioceptive sensory neuron further underlines loss of COX20 contributing to mitochondrial bioenergetic dysfunction as a mechanism in peripheral sensory neuron disease.
Collapse
Affiliation(s)
- Hai-Lin Dong
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China
| | - Yin Ma
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China
| | - Hao Yu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China
| | - Qiao Wei
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China
| | - Jia-Qi Li
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China
| | - Gong-Lu Liu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China
| | - Hong-Fu Li
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China
| | - Lei Chen
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China.,Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Dian-Fu Chen
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China.,Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Ge Bai
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China.,Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Zhi-Ying Wu
- Department of Neurology and Research Center of Neurology in Second Affiliated Hospital, Hangzhou, China.,Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China.,CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai, China
| |
Collapse
|
21
|
Blackout in the powerhouse: clinical phenotypes associated with defects in the assembly of OXPHOS complexes and the mitoribosome. Biochem J 2021; 477:4085-4132. [PMID: 33151299 PMCID: PMC7657662 DOI: 10.1042/bcj20190767] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/29/2020] [Accepted: 10/05/2020] [Indexed: 12/26/2022]
Abstract
Mitochondria produce the bulk of the energy used by almost all eukaryotic cells through oxidative phosphorylation (OXPHOS) which occurs on the four complexes of the respiratory chain and the F1–F0 ATPase. Mitochondrial diseases are a heterogenous group of conditions affecting OXPHOS, either directly through mutation of genes encoding subunits of OXPHOS complexes, or indirectly through mutations in genes encoding proteins supporting this process. These include proteins that promote assembly of the OXPHOS complexes, the post-translational modification of subunits, insertion of cofactors or indeed subunit synthesis. The latter is important for all 13 of the proteins encoded by human mitochondrial DNA, which are synthesised on mitochondrial ribosomes. Together the five OXPHOS complexes and the mitochondrial ribosome are comprised of more than 160 subunits and many more proteins support their biogenesis. Mutations in both nuclear and mitochondrial genes encoding these proteins have been reported to cause mitochondrial disease, many leading to defective complex assembly with the severity of the assembly defect reflecting the severity of the disease. This review aims to act as an interface between the clinical and basic research underpinning our knowledge of OXPHOS complex and ribosome assembly, and the dysfunction of this process in mitochondrial disease.
Collapse
|
22
|
Yamaguchi M, Omori K, Asada S, Yoshida H. Epigenetic Regulation of ALS and CMT: A Lesson from Drosophila Models. Int J Mol Sci 2021; 22:ijms22020491. [PMID: 33419039 PMCID: PMC7825332 DOI: 10.3390/ijms22020491] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/01/2021] [Accepted: 01/03/2021] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is the third most common neurodegenerative disorder and is sometimes associated with frontotemporal dementia. Charcot–Marie–Tooth disease (CMT) is one of the most commonly inherited peripheral neuropathies causing the slow progression of sensory and distal muscle defects. Of note, the severity and progression of CMT symptoms markedly vary. The phenotypic heterogeneity of ALS and CMT suggests the existence of modifiers that determine disease characteristics. Epigenetic regulation of biological functions via gene expression without alterations in the DNA sequence may be an important factor. The methylation of DNA, noncoding RNA, and post-translational modification of histones are the major epigenetic mechanisms. Currently, Drosophila is emerging as a useful ALS and CMT model. In this review, we summarize recent studies linking ALS and CMT to epigenetic regulation with a strong emphasis on approaches using Drosophila models.
Collapse
Affiliation(s)
- Masamitsu Yamaguchi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (K.O.); (S.A.)
- Kansai Gakken Laboratory, Kankyo Eisei Yakuhin Co. Ltd., Seika-cho, Kyoto 619-0237, Japan
- Correspondence: (M.Y.); (H.Y.)
| | - Kentaro Omori
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (K.O.); (S.A.)
| | - Satoshi Asada
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (K.O.); (S.A.)
| | - Hideki Yoshida
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (K.O.); (S.A.)
- Correspondence: (M.Y.); (H.Y.)
| |
Collapse
|
23
|
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: 109] [Impact Index Per Article: 27.3] [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.
Collapse
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
| |
Collapse
|
24
|
Krämer L, Groh C, Herrmann JM. The proteasome: friend and foe of mitochondrial biogenesis. FEBS Lett 2020; 595:1223-1238. [PMID: 33249599 DOI: 10.1002/1873-3468.14010] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/26/2020] [Accepted: 11/01/2020] [Indexed: 01/06/2023]
Abstract
Most mitochondrial proteins are synthesized in the cytosol and subsequently translocated as unfolded polypeptides into mitochondria. Cytosolic chaperones maintain precursor proteins in an import-competent state. This post-translational import reaction is under surveillance of the cytosolic ubiquitin-proteasome system, which carries out several distinguishable activities. On the one hand, the proteasome degrades nonproductive protein precursors from the cytosol and nucleus, import intermediates that are stuck in mitochondrial translocases, and misfolded or damaged proteins from the outer membrane and the intermembrane space. These surveillance activities of the proteasome are essential for mitochondrial functionality, as well as cellular fitness and survival. On the other hand, the proteasome competes with mitochondria for nonimported cytosolic precursor proteins, which can compromise mitochondrial biogenesis. In order to balance the positive and negative effects of the cytosolic protein quality control system on mitochondria, mitochondrial import efficiency directly regulates the capacity of the proteasome via transcription factor Rpn4 in yeast and nuclear respiratory factor (Nrf) 1 and 2 in animal cells. In this review, we provide a thorough overview of how the proteasome regulates mitochondrial biogenesis.
Collapse
Affiliation(s)
- Lena Krämer
- Cell Biology, University of Kaiserslautern, Germany
| | - Carina Groh
- Cell Biology, University of Kaiserslautern, Germany
| | | |
Collapse
|
25
|
Lu JQ, Tarnopolsky MA. Mitochondrial neuropathy and neurogenic features in mitochondrial myopathy. Mitochondrion 2020; 56:52-61. [PMID: 33220502 DOI: 10.1016/j.mito.2020.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/25/2020] [Accepted: 11/02/2020] [Indexed: 01/21/2023]
Abstract
Mitochondrial diseases (MIDs) involve multiple organs including peripheral nerves and skeletal muscle. Mitochondrial neuropathy (MN) and mitochondrial myopathy (MM) are commonly associated and linked at the neuromuscular junction (NMJ). Herein we review MN in connection with neurogenic features of MM, and pathological evidence for the involvement of the peripheral nerve and NMJ in MID patients traditionally assumed to have predominantly MM. MN is not uncommon, but still likely under-reported, and muscle biopsies of MM commonly exhibit neurogenic features. Pathological examination remains the gold standard to assess the nerve and muscle changes in patients with MIDs. Ultrastructural studies by electron microscopy are often necessary to fully characterize the pathology of mitochondrial cytopathy in MN and MM.
Collapse
Affiliation(s)
- Jian-Qiang Lu
- Department of Pathology and Molecular Medicine/Neuropathology, McMaster University, Hamilton, Ontario, Canada.
| | - Mark A Tarnopolsky
- Department of Medicine/Neurology, McMaster University, Hamilton, Ontario, Canada; Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
26
|
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: 61] [Impact Index Per Article: 15.3] [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.
Collapse
|
27
|
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.
Collapse
|
28
|
Krauss R, Bosanac T, Devraj R, Engber T, Hughes RO. Axons Matter: The Promise of Treating Neurodegenerative Disorders by Targeting SARM1-Mediated Axonal Degeneration. Trends Pharmacol Sci 2020; 41:281-293. [DOI: 10.1016/j.tips.2020.01.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 02/06/2023]
|
29
|
Beaudin M, Matilla-Dueñas A, Soong BW, Pedroso JL, Barsottini OG, Mitoma H, Tsuji S, Schmahmann JD, Manto M, Rouleau GA, Klein C, Dupre N. The Classification of Autosomal Recessive Cerebellar Ataxias: a Consensus Statement from the Society for Research on the Cerebellum and Ataxias Task Force. CEREBELLUM (LONDON, ENGLAND) 2019; 18:1098-1125. [PMID: 31267374 PMCID: PMC6867988 DOI: 10.1007/s12311-019-01052-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
There is currently no accepted classification of autosomal recessive cerebellar ataxias, a group of disorders characterized by important genetic heterogeneity and complex phenotypes. The objective of this task force was to build a consensus on the classification of autosomal recessive ataxias in order to develop a general approach to a patient presenting with ataxia, organize disorders according to clinical presentation, and define this field of research by identifying common pathogenic molecular mechanisms in these disorders. The work of this task force was based on a previously published systematic scoping review of the literature that identified autosomal recessive disorders characterized primarily by cerebellar motor dysfunction and cerebellar degeneration. The task force regrouped 12 international ataxia experts who decided on general orientation and specific issues. We identified 59 disorders that are classified as primary autosomal recessive cerebellar ataxias. For each of these disorders, we present geographical and ethnical specificities along with distinctive clinical and imagery features. These primary recessive ataxias were organized in a clinical and a pathophysiological classification, and we present a general clinical approach to the patient presenting with ataxia. We also identified a list of 48 complex multisystem disorders that are associated with ataxia and should be included in the differential diagnosis of autosomal recessive ataxias. This classification is the result of a consensus among a panel of international experts, and it promotes a unified understanding of autosomal recessive cerebellar disorders for clinicians and researchers.
Collapse
Affiliation(s)
- Marie Beaudin
- Axe Neurosciences, CHU de Québec-Université Laval, Québec, QC, Canada
- Department of Medicine, Faculty of Medicine, Université Laval, Quebec City, QC, Canada
| | - Antoni Matilla-Dueñas
- Department of Neuroscience, Health Sciences Research Institute Germans Trias i Pujol (IGTP), Universitat Autònoma de Barcelona, Badalona, Barcelona, Spain
| | - Bing-Weng Soong
- Department of Neurology, Shuang Ho Hospital and Taipei Neuroscience Institute, Taipei Medical University, Taipei, Taiwan, Republic of China
- National Yang-Ming University School of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, Republic of China
| | - Jose Luiz Pedroso
- Ataxia Unit, Department of Neurology, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Orlando G Barsottini
- Ataxia Unit, Department of Neurology, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Hiroshi Mitoma
- Medical Education Promotion Center, Tokyo Medical University, Tokyo, Japan
| | - Shoji Tsuji
- The University of Tokyo, Tokyo, Japan
- International University of Health and Welfare, Chiba, Japan
| | - Jeremy D Schmahmann
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Mario Manto
- Service de Neurologie, Médiathèque Jean Jacquy, CHU-Charleroi, 6000, Charleroi, Belgium
- Service des Neurosciences, UMons, Mons, Belgium
| | | | | | - Nicolas Dupre
- Axe Neurosciences, CHU de Québec-Université Laval, Québec, QC, Canada.
- Department of Medicine, Faculty of Medicine, Université Laval, Quebec City, QC, Canada.
| |
Collapse
|
30
|
Identification of CR43467 encoding a long non-coding RNA as a novel genetic interactant with dFIG4, a CMT-causing gene. Exp Cell Res 2019; 386:111711. [PMID: 31704059 DOI: 10.1016/j.yexcr.2019.111711] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/30/2019] [Accepted: 11/01/2019] [Indexed: 12/15/2022]
Abstract
The eye imaginal disc-specific knockdown of dFIG4, a Drosophila homolog of FIG4 that is one of the Charcot-Marie-Tooth disease (CMT)-causing genes, induces an aberrant adult compound eye morphology, the so-called rough eye phenotype. We previously performed modifier screening on the dFIG4 knockdown-induced rough eye phenotype and identified several genes, including CR18854, encoding a long non-coding RNA (lncRNA) as genetic interactants with dFIG4. In the present study, in more extensive genetic screening, we found that the deletion of a gene locus encoding both Odorant rector 46a (Or46a) and lncRNA CR43467 effectively suppressed the rough eye phenotype induced by the knockdown of dFIG4. Both genes were located on the same locus, but oriented in opposite directions. In order to identify which of these genes is responsible for the suppression of the rough eye phenotype, we established a CR43467-specific knockdown line using the CRISPR-dCas9 system. By using this system, we demonstrated that the CR43467 gene, but not the Or46a gene, genetically interacted with the dFIG4 gene. The knockdown of CR43467 rescued the reductions in the length of synaptic branches and number of boutons at neuromuscular junctions induced by the knockdown of dFIG4. The vacuole enlargement phenotype induced by the fat body-specific dFIG4 knockdown was also effectively suppressed by the knockdown of CR43467. The knockdown of CR43467 also suppressed the rough eye phenotype induced by other peripheral neuropathy-related genes, such as dCOA7, dHADHB, and dPDHB. We herein identified another gene encoding lncRNA, CR43467 as a genetic interactant with the CMT-causing gene.
Collapse
|
31
|
Scott P, Al Kindi A, Al Fahdi A, Al Yarubi N, Bruwer Z, Al Adawi S, Nandhagopal R. Spinocerebellar ataxia with axonal neuropathy type 1 revisited. J Clin Neurosci 2019; 67:139-144. [PMID: 31182267 DOI: 10.1016/j.jocn.2019.05.060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/03/2019] [Accepted: 05/28/2019] [Indexed: 01/17/2023]
Abstract
Spinocerebellar ataxia with axonal neuropathy type 1 (SCAN1; OMIM #607250), an exceedingly rare disorder having been documented in only a single family from Saudi Arabia, is the result of an unusual mutation in the tyrosyl DNA phosphodiesterase 1 gene (TDP1). We performed high-throughput sequencing (whole exome and ataxia gene panel) in two apparently unrelated Omani families segregating sensorimotor neuropathy and ataxia in an autosomal recessive fashion. Following validation by Sanger sequencing, all affected subjects (n = 4) were confirmed to carry the known SCAN1 pathogenic homozygous variant in the TDP1 gene, NM_001008744.1:c.1478A > G (p.His493Arg). In keeping with the initial description, our patients demonstrated progressive ataxia, cerebellar atrophy and disabling axonal sensori-motor neuropathy (n = 4), hypercholesterolemia (n = 2) and elevated serum alpha fetoprotein (n = 3). In addition, our patients also had mild cognitive deficits in multiple domains (n = 3), a feature not previously reported. Our findings independently revalidate the phenotype of TDP1 mutation and expand the clinical spectrum to include mild cognitive deficits. Haplotype sharing, as determined by DNA microarray (CytoScan HD), attests to a possible common founder mutation in the Arab population.
Collapse
Affiliation(s)
- Patrick Scott
- Molecular Genetics and Genomics Laboratory (PS, AAF, NAY), P.O. Box. 35, Sultan Qaboos University Hospital, Al-Khod, Zip 123, Muscat, Oman
| | - Adila Al Kindi
- Department of Clinical Genetics (AAK, ZB), P.O. Box. 35, Sultan Qaboos University Hospital, Al-Khod, Zip 123, Muscat, Oman
| | - Amira Al Fahdi
- Molecular Genetics and Genomics Laboratory (PS, AAF, NAY), P.O. Box. 35, Sultan Qaboos University Hospital, Al-Khod, Zip 123, Muscat, Oman
| | - Naeema Al Yarubi
- Molecular Genetics and Genomics Laboratory (PS, AAF, NAY), P.O. Box. 35, Sultan Qaboos University Hospital, Al-Khod, Zip 123, Muscat, Oman
| | - Zandre Bruwer
- Department of Clinical Genetics (AAK, ZB), P.O. Box. 35, Sultan Qaboos University Hospital, Al-Khod, Zip 123, Muscat, Oman
| | - Samir Al Adawi
- Department of Behavioral Medicine (SAA), P.O. Box. 35, Sultan Qaboos University Hospital, Al-Khod, Zip 123, Muscat, Oman
| | - Ramachandiran Nandhagopal
- Neurology Unit, Department of Medicine (RN), P.O. Box. 35, Sultan Qaboos University, Al-Khod, Zip 123, Muscat, Oman. https://orcid.org/0000-0002-2379-0055
| |
Collapse
|
32
|
Mohanraj K, Wasilewski M, Benincá C, Cysewski D, Poznanski J, Sakowska P, Bugajska Z, Deckers M, Dennerlein S, Fernandez‐Vizarra E, Rehling P, Dadlez M, Zeviani M, Chacinska A. Inhibition of proteasome rescues a pathogenic variant of respiratory chain assembly factor COA7. EMBO Mol Med 2019; 11:emmm.201809561. [PMID: 30885959 PMCID: PMC6505684 DOI: 10.15252/emmm.201809561] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Nuclear and mitochondrial genome mutations lead to various mitochondrial diseases, many of which affect the mitochondrial respiratory chain. The proteome of the intermembrane space (IMS) of mitochondria consists of several important assembly factors that participate in the biogenesis of mitochondrial respiratory chain complexes. The present study comprehensively analyzed a recently identified IMS protein cytochrome c oxidase assembly factor 7 (COA7), or RESpiratory chain Assembly 1 (RESA1) factor that is associated with a rare form of mitochondrial leukoencephalopathy and complex IV deficiency. We found that COA7 requires the mitochondrial IMS import and assembly (MIA) pathway for efficient accumulation in the IMS We also found that pathogenic mutant versions of COA7 are imported slower than the wild-type protein, and mislocalized proteins are degraded in the cytosol by the proteasome. Interestingly, proteasome inhibition rescued both the mitochondrial localization of COA7 and complex IV activity in patient-derived fibroblasts. We propose proteasome inhibition as a novel therapeutic approach for a broad range of mitochondrial pathologies associated with the decreased levels of mitochondrial proteins.
Collapse
Affiliation(s)
- Karthik Mohanraj
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland,ReMedy International Research Agenda UnitCentre of New TechnologiesUniversity of WarsawWarsawPoland,Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
| | - Michal Wasilewski
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland,Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
| | | | - Dominik Cysewski
- Mass Spectrometry LabDepartment of BiophysicsInstitute of Biochemistry and BiophysicsWarsawPoland
| | - Jaroslaw Poznanski
- Department of BiophysicsInstitute of Biochemistry and BiophysicsWarsawPoland
| | - Paulina Sakowska
- Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
| | - Zaneta Bugajska
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland
| | - Markus Deckers
- Department of Cellular BiochemistryUniversity of GöttingenGöttingenGermany
| | - Sven Dennerlein
- Department of Cellular BiochemistryUniversity of GöttingenGöttingenGermany
| | | | - Peter Rehling
- Department of Cellular BiochemistryUniversity of GöttingenGöttingenGermany,Max Planck Institute for Biophysical ChemistryGöttingenGermany
| | - Michal Dadlez
- Mass Spectrometry LabDepartment of BiophysicsInstitute of Biochemistry and BiophysicsWarsawPoland
| | - Massimo Zeviani
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Agnieszka Chacinska
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland,ReMedy International Research Agenda UnitCentre of New TechnologiesUniversity of WarsawWarsawPoland,Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
| |
Collapse
|
33
|
Finsterer J, Zarrouk‐Mahjoub S. Mitochondrial ataxia is genetically and phenotypically heterogeneous. CNS Neurosci Ther 2018; 24:1301-1302. [PMID: 29998495 PMCID: PMC6490036 DOI: 10.1111/cns.13031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
| | - Sinda Zarrouk‐Mahjoub
- Pasteur Institute of TunisUniversity of Tunis El Manar and Genomics PlatformTunisTunisia
| |
Collapse
|
34
|
Yamaguchi M, Takashima H. Drosophila Charcot-Marie-Tooth Disease Models. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1076:97-117. [PMID: 29951817 DOI: 10.1007/978-981-13-0529-0_7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Charcot-Marie-Tooth disease (CMT) was initially described in 1886. It is characterized by defects in the peripheral nervous system, including sensory and motor neurons. Although more than 80 CMT-causing genes have been identified to date, an effective therapy has not yet been developed for this disease. Since Drosophila does not have axons surrounded by myelin sheaths or Schwann cells, the establishment of a demyelinating CMT model is not appropriate. In this chapter, after overviewing CMT, examples of Drosophila CMT models with axonal neuropathy and other animal CMT models are described.
Collapse
Affiliation(s)
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| |
Collapse
|