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Kinnart I, Manders L, Heyninck T, Imberechts D, Praschberger R, Schoovaerts N, Verfaillie C, Verstreken P, Vandenberghe W. Elevated α-synuclein levels inhibit mitophagic flux. NPJ Parkinsons Dis 2024; 10:80. [PMID: 38594264 PMCID: PMC11004019 DOI: 10.1038/s41531-024-00696-0] [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: 09/14/2023] [Accepted: 03/26/2024] [Indexed: 04/11/2024] Open
Abstract
The pathogenic effect of SNCA gene multiplications indicates that elevation of wild-type α-synuclein levels is sufficient to cause Parkinson's disease (PD). Mitochondria have been proposed to be a major target of α-synuclein-induced damage. PINK1/parkin/DJ-1-mediated mitophagy is a defense strategy that allows cells to selectively eliminate severely damaged mitochondria. Here, we quantified mitophagic flux and non-mitochondrial autophagic flux in three models of increased α-synuclein expression: 1/Drosophila melanogaster that transgenically express human wild-type and mutant α-synuclein in flight muscle; 2/human skin fibroblasts transfected with α-synuclein or β-synuclein; and 3/human induced pluripotent stem cell (iPSC)-derived neurons carrying an extra copy of wild-type SNCA under control of a doxycycline-inducible promoter, allowing titratable α-synuclein upregulation. In each model, elevated α-synuclein levels potently suppressed mitophagic flux, while non-mitochondrial autophagy was preserved. In human neurons, a twofold increase in wild-type α-synuclein was already sufficient to induce this effect. PINK1 and parkin activation and mitochondrial translocation of DJ-1 after mitochondrial depolarization were not affected by α-synuclein upregulation. Overexpression of the actin-severing protein cofilin or treatment with CK666, an inhibitor of the actin-related protein 2/3 (Arp2/3) complex, rescued mitophagy in neurons with increased α-synuclein, suggesting that excessive actin network stabilization mediated the mitophagy defect. In conclusion, elevated α-synuclein levels inhibit mitophagic flux. Disruption of actin dynamics may play a key role in this effect.
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Affiliation(s)
- Inge Kinnart
- Department of Neurosciences, Laboratory for Parkinson Research, KU Leuven, Leuven, Belgium
| | - Liselot Manders
- Department of Neurosciences, Laboratory for Parkinson Research, KU Leuven, Leuven, Belgium
| | - Thibaut Heyninck
- Department of Neurosciences, Laboratory for Parkinson Research, KU Leuven, Leuven, Belgium
| | - Dorien Imberechts
- Department of Neurosciences, Laboratory for Parkinson Research, KU Leuven, Leuven, Belgium
| | - Roman Praschberger
- Department of Neurosciences, Laboratory for Neuronal Communication, KU Leuven, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
| | - Nils Schoovaerts
- Department of Neurosciences, Laboratory for Neuronal Communication, KU Leuven, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
| | | | - Patrik Verstreken
- Department of Neurosciences, Laboratory for Neuronal Communication, KU Leuven, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
| | - Wim Vandenberghe
- Department of Neurosciences, Laboratory for Parkinson Research, KU Leuven, Leuven, Belgium.
- Department of Neurology, University Hospitals Leuven, Leuven, Belgium.
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2
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Jing S, Yi X. Exome sequencing reveals PPEF2 variant associated with high myopia. Gene 2024; 897:148091. [PMID: 38110044 DOI: 10.1016/j.gene.2023.148091] [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: 11/21/2023] [Revised: 12/08/2023] [Accepted: 12/14/2023] [Indexed: 12/20/2023]
Abstract
High myopia (HM) is a serious blinding eye disease, and genetic factors play an important role in the development of HM. In this study, whole exome sequencing (WES) was used to identify a novel variant c.A875G of the PPEF2 for a large Uyghur family with nonsyndromic HM. The variant was verified to cosegregate with HM in the family using Sanger sequencing. Another novel variant c.1959C > G in PPEF2 was identified in one of 100 sporadic cases of HM by multiplex PCR targeted amplicon sequencing (MTA-seq). The Ppef2 was verified that mainly expressed in the retinal pigment epithelium (RPE), choroid and retina tissues. Immunofluorescence (IF) and immunohistochemistry (IHC) assays showed that the PPEF2 was strongly expressed in the inner segment layer formed by photoreceptor protrusions, as well as in the outer nuclear layer. Compared with the wild-type, the c.A875G resulted in reduced protein levels but had no effect on protein subcellular localization in cells. In addition, the c.A875G variant resulted in a decreased migratory and proliferative capacity but promoted apoptosis in cells. In summary, PPEF2 was identified as a novel HM-causing gene, and this variant in PPEF2 might cause HM by regulating the migration, proliferation and apoptosis of myopia-related cells.
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Affiliation(s)
- Sili Jing
- Shaanxi Eye Hospital, Xi'an People's Hospital (Xi'an Fourth Hospital), Affiliated People's Hospital of Northwest University, Xian, 710004, China; Ophthalmology, Xinjiang Medical University Affiliated First Hospital, Urumqi, Xinjiang, China
| | - Xianglong Yi
- Ophthalmology, Xinjiang Medical University Affiliated First Hospital, Urumqi, Xinjiang, China.
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3
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Hou K, Liu T, Li J, Xian M, Sun L, Wei J. Liquid-liquid phase separation regulates alpha-synuclein aggregate and mitophagy in Parkinson's disease. Front Neurosci 2023; 17:1250532. [PMID: 37781241 PMCID: PMC10536155 DOI: 10.3389/fnins.2023.1250532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 08/29/2023] [Indexed: 10/03/2023] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease in the world, and alpha-synuclein (α-syn) abnormal aggregate and mitochondrial dysfunction play a crucial role in its pathological development. Recent studies have revealed that proteins can form condensates through liquid-liquid phase separation (LLPS), and LLPS has been found to be widely present in α-syn aberrant aggregate and mitophagy-related protein physiological processes. This review summarizes the occurrence of α-syn LLPS and its influencing factors, introduces the production and transformation of the related protein LLPS during PINK1-Parkin-mediated mitophagy, hoping to provide new ideas and methods for the study of PD pathology.
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Affiliation(s)
- Kaiying Hou
- School of Life Sciences, Henan University, Kaifeng, China
| | - Tingting Liu
- School of Life Sciences, Henan University, Kaifeng, China
| | - Jingwen Li
- School of Life Sciences, Henan University, Kaifeng, China
| | - Meiyan Xian
- School of Life Sciences, Henan University, Kaifeng, China
| | - Lin Sun
- College of Chemistry and Molecular Sciences, Henan University, Kaifeng, China
| | - Jianshe Wei
- School of Life Sciences, Henan University, Kaifeng, China
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4
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Williamson MG, Madureira M, McGuinness W, Heon-Roberts R, Mock ED, Naidoo K, Cramb KML, Caiazza MC, Malpartida AB, Lavelle M, Savory K, Humble SW, Patterson R, Davis JB, Connor-Robson N, Ryan BJ, Wade-Martins R. Mitochondrial dysfunction and mitophagy defects in LRRK2-R1441C Parkinson's disease models. Hum Mol Genet 2023; 32:2808-2821. [PMID: 37384414 PMCID: PMC10481106 DOI: 10.1093/hmg/ddad102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 07/01/2023] Open
Abstract
Mutations in the Leucine-Rich Repeat Kinase 2 (LRRK2) gene have been identified as one of the most common genetic causes of Parkinson's disease (PD). The LRRK2 PD-associated mutations LRRK2G2019S and LRRK2R1441C, located in the kinase domain and in the ROC-COR domain, respectively, have been demonstrated to impair mitochondrial function. Here, we sought to further our understanding of mitochondrial health and mitophagy by integrating data from LRRK2R1441C rat primary cortical and human induced pluripotent stem cell-derived dopamine (iPSC-DA) neuronal cultures as models of PD. We found that LRRK2R1441C neurons exhibit decreased mitochondrial membrane potential, impaired mitochondrial function and decreased basal mitophagy levels. Mitochondrial morphology was altered in LRRK2R1441C iPSC-DA but not in cortical neuronal cultures or aged striatal tissue, indicating a cell-type-specific phenotype. Additionally, LRRK2R1441C but not LRRK2G2019S neurons demonstrated decreased levels of the mitophagy marker pS65Ub in response to mitochondrial damage, which could disrupt degradation of damaged mitochondria. This impaired mitophagy activation and mitochondrial function were not corrected by the LRRK2 inhibitor MLi-2 in LRRK2R1441C iPSC-DA neuronal cultures. Furthermore, we demonstrate LRRK2 interaction with MIRO1, a protein necessary to stabilize and to anchor mitochondria for transport, occurs at mitochondria, in a genotype-independent manner. Despite this, we found that degradation of MIRO1 was impaired in LRRK2R1441C cultures upon induced mitochondrial damage, suggesting a divergent mechanism from the LRRK2G2019S mutation.
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Affiliation(s)
- Matthew G Williamson
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Marta Madureira
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
- ICBAS, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira, 228, Porto 4050-313, Portugal
| | - William McGuinness
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Rachel Heon-Roberts
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Elliot D Mock
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Kalina Naidoo
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Kaitlyn M L Cramb
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Maria-Claudia Caiazza
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Ana B Malpartida
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
| | - Martha Lavelle
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Katrina Savory
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Stewart W Humble
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
- National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda, MD, 20892, USA
| | - Ryan Patterson
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda, MD, 20892, USA
| | - John B Davis
- Oxford Drug Discovery Institute, Centre of Medicines Discovery, University of Oxford, NDM Research Building, Old Road Campus, Oxford OX3 7FZ, UK
| | - Natalie Connor-Robson
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
| | - Brent J Ryan
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
| | - Richard Wade-Martins
- Oxford Parkinson’s Disease Centre and Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford OX1 3QU, UK
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5
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Dong Y, Zhuang XX, Wang YT, Tan J, Feng D, Li M, Zhong Q, Song Z, Shen HM, Fang EF, Lu JH. Chemical mitophagy modulators: Drug development strategies and novel regulatory mechanisms. Pharmacol Res 2023; 194:106835. [PMID: 37348691 DOI: 10.1016/j.phrs.2023.106835] [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: 05/13/2023] [Revised: 06/09/2023] [Accepted: 06/19/2023] [Indexed: 06/24/2023]
Abstract
Maintaining mitochondrial homeostasis is a potential therapeutic strategy for various diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic disorders, and cancer. Selective degradation of mitochondria by autophagy (mitophagy) is a fundamental mitochondrial quality control mechanism conserved from yeast to humans. Indeed, small-molecule modulators of mitophagy are valuable pharmaceutical tools that can be used to dissect complex biological processes and turn them into potential drugs. In the past few years, pharmacological regulation of mitophagy has shown promising therapeutic efficacy in various disease models. However, with the increasing number of chemical mitophagy modulator studies, frequent methodological flaws can be observed, leading some studies to draw unreliable or misleading conclusions. This review attempts (a) to summarize the molecular mechanisms of mitophagy; (b) to propose a Mitophagy Modulator Characterization System (MMCS); (c) to perform a comprehensive analysis of methods used to characterize mitophagy modulators, covering publications over the past 20 years; (d) to provide novel targets for pharmacological intervention of mitophagy. We believe this review will provide a panorama of current research on chemical mitophagy modulators and promote the development of safe and robust mitophagy modulators with therapeutic potential by introducing high methodological standards.
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Affiliation(s)
- Yu Dong
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, 999078, Macau
| | - Xu-Xu Zhuang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, 999078, Macau
| | - Yi-Ting Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, 999078, Macau
| | - Jieqiong Tan
- Center for medical genetics, Central South University, Changsha 410031, Hunan, China
| | - Du Feng
- Key Laboratory of Protein Modification and Degradation, State Key Laboratory of Respiratory Disease, College of Basic Medical Science, Guangzhou Medical University, Guangzhou 511436, Guangdong, China
| | - Min Li
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson's Disease Research, School of Chinese Medicine, Hong Kong Baptist University, 999077, Hong Kong Special Administrative Region
| | - Qing Zhong
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Zhiyin Song
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Frontier Science Center for Immunology and Metabolism, Renmin Hospital of Wuhan University, Wuhan University, Wuhan 430072, Hubei, China
| | - Han-Ming Shen
- Department of Biomedical Sciences, Faculty of Health Sciences, Ministry of Education Frontiers Science Center for Precision Oncology, University of Macau, 999078, Macau
| | - Evandro F Fang
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
| | - Jia-Hong Lu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, 999078, Macau.
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6
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Moradi Vastegani S, Nasrolahi A, Ghaderi S, Belali R, Rashno M, Farzaneh M, Khoshnam SE. Mitochondrial Dysfunction and Parkinson's Disease: Pathogenesis and Therapeutic Strategies. Neurochem Res 2023:10.1007/s11064-023-03904-0. [PMID: 36943668 DOI: 10.1007/s11064-023-03904-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/21/2023] [Accepted: 02/28/2023] [Indexed: 03/23/2023]
Abstract
Parkinson's disease (PD) is a common age-related neurodegenerative disorder whose pathogenesis is not completely understood. Mitochondrial dysfunction and increased oxidative stress have been considered as major causes and central events responsible for the progressive degeneration of dopaminergic (DA) neurons in PD. Therefore, investigating mitochondrial disorders plays a role in understanding the pathogenesis of PD and can be an important therapeutic target for this disease. This study discusses the effect of environmental, genetic and biological factors on mitochondrial dysfunction and also focuses on the mitochondrial molecular mechanisms underlying neurodegeneration, and its possible therapeutic targets in PD, including reactive oxygen species generation, calcium overload, inflammasome activation, apoptosis, mitophagy, mitochondrial biogenesis, and mitochondrial dynamics. Other potential therapeutic strategies such as mitochondrial transfer/transplantation, targeting microRNAs, using stem cells, photobiomodulation, diet, and exercise were also discussed in this review, which may provide valuable insights into clinical aspects. A better understanding of the roles of mitochondria in the pathophysiology of PD may provide a rationale for designing novel therapeutic interventions in our fight against PD.
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Affiliation(s)
- Sadegh Moradi Vastegani
- Persian Gulf Physiology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Ava Nasrolahi
- Infectious Ophthalmologic Research Center, Imam Khomeini Hospital Clinical Research Development Unit, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Shahab Ghaderi
- Department of Neuroscience, School of Science and Advanced Technologies in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Rafie Belali
- Persian Gulf Physiology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Masome Rashno
- Asadabad School of Medical Sciences, Asadabad, Iran
- Student Research Committee, Asadabad School of Medical Sciences, Asadabad, Iran
| | - Maryam Farzaneh
- Fertility, Infertility and Perinatology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Seyed Esmaeil Khoshnam
- Persian Gulf Physiology Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
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7
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Usher JL, Sanchez‐Martinez A, Terriente‐Felix A, Chen P, Lee JJ, Chen C, Whitworth AJ. Parkin drives pS65-Ub turnover independently of canonical autophagy in Drosophila. EMBO Rep 2022; 23:e53552. [PMID: 36250243 PMCID: PMC9724668 DOI: 10.15252/embr.202153552] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/05/2022] [Accepted: 09/20/2022] [Indexed: 12/12/2022] Open
Abstract
Parkinson's disease-related proteins, PINK1 and Parkin, act in a common pathway to maintain mitochondrial quality control. While the PINK1-Parkin pathway can promote autophagic mitochondrial turnover (mitophagy) following mitochondrial toxification in cell culture, alternative quality control pathways are suggested. To analyse the mechanisms by which the PINK1-Parkin pathway operates in vivo, we developed methods to detect Ser65-phosphorylated ubiquitin (pS65-Ub) in Drosophila. Exposure to the oxidant paraquat led to robust, Pink1-dependent pS65-Ub production, while pS65-Ub accumulates in unstimulated parkin-null flies, consistent with blocked degradation. Additionally, we show that pS65-Ub specifically accumulates on disrupted mitochondria in vivo. Depletion of the core autophagy proteins Atg1, Atg5 and Atg8a did not cause pS65-Ub accumulation to the same extent as loss of parkin, and overexpression of parkin promoted turnover of both basal and paraquat-induced pS65-Ub in an Atg5-null background. Thus, we have established that pS65-Ub immunodetection can be used to analyse Pink1-Parkin function in vivo as an alternative to reporter constructs. Moreover, our findings suggest that the Pink1-Parkin pathway can promote mitochondrial turnover independently of canonical autophagy in vivo.
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Affiliation(s)
- Joanne L Usher
- MRC Mitochondrial Biology UnitCambridgeUK
- PNAC Division, MRC Laboratory of Molecular BiologyCambridgeUK
- Present address:
MSD R&D Innovation CentreLondonUK
| | | | | | - Po‐Lin Chen
- National Institute of Infectious Diseases and VaccinologyNational Health Research InstitutesZhunanTaiwan
| | | | - Chun‐Hong Chen
- National Institute of Infectious Diseases and VaccinologyNational Health Research InstitutesZhunanTaiwan
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8
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Abstract
Mitochondria are crucial organelles that play a central role in various cell signaling and metabolic pathways. A healthy mitochondrial population is maintained through a series of quality control pathways and requires a fine-tuned balance between mitochondrial biogenesis and degradation. Defective targeting of dysfunctional mitochondria to lysosomes through mitophagy has been linked to several diseases, but the underlying mechanisms and the relative importance of distinct mitophagy pathways in vivo are largely unknown. In this Cell Science at a Glance and the accompanying poster, we describe our current understanding of how parts of, or whole, mitochondria are recognized by the autophagic machinery and targeted to lysosomes for degradation. We also discuss how this might be regulated under different physiological conditions to maintain mitochondrial and cellular health.
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Affiliation(s)
- Ian G. Ganley
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Anne Simonsen
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0372 Oslo, Norway
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, University of Oslo, 0318 Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital Montebello, 0379 Oslo, Norway
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9
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Eldeeb MA, Thomas RA, Ragheb MA, Fallahi A, Fon EA. Mitochondrial quality control in health and in Parkinson's disease. Physiol Rev 2022; 102:1721-1755. [PMID: 35466694 DOI: 10.1152/physrev.00041.2021] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
As a central hub for cellular metabolism and intracellular signalling, the mitochondrion is a pivotal organelle, dysfunction of which has been linked to several human diseases including neurodegenerative disorders, and in particular Parkinson's disease. An inherent challenge that mitochondria face is the continuous exposure to diverse stresses which increase their likelihood of dysregulation. In response, eukaryotic cells have evolved sophisticated quality control mechanisms to monitor, identify, repair and/or eliminate abnormal or misfolded proteins within the mitochondrion and/or the dysfunctional mitochondrion itself. Chaperones identify unstable or otherwise abnormal conformations in mitochondrial proteins and can promote their refolding to recover their correct conformation and stability. However, if repair is not possible, the abnormal protein is selectively degraded to prevent potentially damaging interactions with other proteins or its oligomerization into toxic multimeric complexes. The autophagic-lysosomal system and the ubiquitin-proteasome system mediate the selective and targeted degradation of such abnormal or misfolded protein species. Mitophagy (a specific kind of autophagy) mediates the selective elimination of dysfunctional mitochondria, in order to prevent the deleterious effects the dysfunctional organelles within the cell. Despite our increasing understanding of the molecular responses toward dysfunctional mitochondria, many key aspects remain relatively poorly understood. Herein, we review the emerging mechanisms of mitochondrial quality control including quality control strategies coupled to mitochondrial import mechanisms. In addition, we review the molecular mechanisms regulating mitophagy with an emphasis on the regulation of PINK1/PARKIN-mediated mitophagy in cellular physiology and in the context of Parkinson's disease cell biology.
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Affiliation(s)
- Mohamed A Eldeeb
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Rhalena A Thomas
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Mohamed A Ragheb
- Chemistry Department (Biochemistry Division), Faculty of Science, Cairo University, Giza, Egypt
| | - Armaan Fallahi
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Edward A Fon
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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10
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Mahalaxmi G, Ashok S, Arun G, Srinivas G. Albumin binds to uncoupler CCCP to diminish depolarization of mitochondria. Toxicol In Vitro 2022; 80:105325. [PMID: 35121064 DOI: 10.1016/j.tiv.2022.105325] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 01/14/2022] [Accepted: 01/27/2022] [Indexed: 11/19/2022]
Abstract
Mitochondria are at the core of cellular energy metabolism and are also involved in the oxidative stress response and programmed cell death pathways. Mitochondrial dysfunction is found to be associated with many disease conditions like metabolic syndrome, neurodegenerative disorders, coronary artery diseases, cancer, etc. This has generated considerable interest in the scientific community over the assessment of mitochondrial function and mitochondrial damage. One of the most common methodologies in these studies is by analysing the mitochondrial activity in the presence of mitochondrial substrates, inhibitors and uncouplers. Apart from the specific effects of these molecules on mitochondria, their interactions with the components of the experimental system could interfere with the results derived. Therefore, the role some specific experimental conditions would have on the outcome should be carefully elucidated. Fetal Bovine Serum or Bovine Serum Albumin (BSA); routinely used in in vitro experiments for their growth promoting and surfactant properties; can have profound impact on the pharmacokinetics of chemical compounds as albumin residue can bind to and affect their bioavailability. In the present study, we demonstrate that Carbonyl cyanide 3-chlorophenylhydrazone (CCCP) induced mitochondrial depolarization is hindered in the presence of albumin due to the molecular interaction between CCCP and albumin.
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Affiliation(s)
- Ganjoo Mahalaxmi
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum 695011, Kerala, India
| | - Sivasailam Ashok
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum 695011, Kerala, India
| | - Gangadharan Arun
- Department of Biotechnology and Microbiology, Kannur University, Kerala, India
| | - Gopala Srinivas
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum 695011, Kerala, India.
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11
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Lechado Terradas A, Zittlau KI, Macek B, Fraiberg M, Elazar Z, Kahle PJ. Regulation of mitochondrial cargo-selective autophagy by posttranslational modifications. J Biol Chem 2021; 297:101339. [PMID: 34688664 PMCID: PMC8591368 DOI: 10.1016/j.jbc.2021.101339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 10/14/2021] [Accepted: 10/20/2021] [Indexed: 12/18/2022] Open
Abstract
Mitochondria are important organelles in eukaryotes. Turnover and quality control of mitochondria are regulated at the transcriptional and posttranslational level by several cellular mechanisms. Removal of defective mitochondrial proteins is mediated by mitochondria resident proteases or by proteasomal degradation of individual proteins. Clearance of bulk mitochondria occurs via a selective form of autophagy termed mitophagy. In yeast and some developing metazoan cells (e.g., oocytes and reticulocytes), mitochondria are largely removed by ubiquitin-independent mechanisms. In such cases, the regulation of mitophagy is mediated via phosphorylation of mitochondria-anchored autophagy receptors. On the other hand, ubiquitin-dependent recruitment of cytosolic autophagy receptors occurs in situations of cellular stress or disease, where dysfunctional mitochondria would cause oxidative damage. In mammalian cells, a well-studied ubiquitin-dependent mitophagy pathway induced by mitochondrial depolarization is regulated by the mitochondrial protein kinase PINK1, which upon activation recruits the ubiquitin ligase parkin. Here, we review mechanisms of mitophagy with an emphasis on posttranslational modifications that regulate various mitophagy pathways. We describe the autophagy components involved with particular emphasis on posttranslational modifications. We detail the phosphorylations mediated by PINK1 and parkin-mediated ubiquitylations of mitochondrial proteins that can be modulated by deubiquitylating enzymes. We also discuss the role of accessory factors regulating mitochondrial fission/fusion and the interplay with pro- and antiapoptotic Bcl-2 family members. Comprehensive knowledge of the processes of mitophagy is essential for the understanding of vital mitochondrial turnover in health and disease.
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Affiliation(s)
- Anna Lechado Terradas
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany; Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | | | - Boris Macek
- Proteome Center Tübingen, University of Tübingen, Tübingen, Germany
| | - Milana Fraiberg
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Zvulun Elazar
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Philipp J Kahle
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany; Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany; German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany.
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12
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Pollock L, Jardine J, Urbé S, Clague MJ. The PINK1 repertoire: Not just a one trick pony. Bioessays 2021; 43:e2100168. [PMID: 34617288 DOI: 10.1002/bies.202100168] [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: 07/05/2021] [Revised: 08/27/2021] [Accepted: 08/30/2021] [Indexed: 12/15/2022]
Abstract
PTEN-induced kinase 1 (PINK1) is a Parkinson's disease gene that acts as a sensor for mitochondrial damage. Its best understood role involves phosphorylating ubiquitin and the E3 ligase Parkin (PRKN) to trigger a ubiquitylation cascade that results in selective clearance of damaged mitochondria through mitophagy. Here we focus on other physiological roles of PINK1. Some of these also lie upstream of Parkin but others represent autonomous functions, for which alternative substrates have been identified. We argue that PINK1 orchestrates a multi-arm response to mitochondrial damage that impacts on mitochondrial architecture and biogenesis, calcium handling, transcription and translation. We further discuss a role for PINK1 in immune signalling co-ordinated at mitochondria and consider the significance of a freely diffusible cleavage product, that is constitutively generated and degraded under basal conditions.
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Affiliation(s)
- Liam Pollock
- Department of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Jane Jardine
- Université de Nantes, CNRS, Inserm, CRCINA, Nantes, France
| | - Sylvie Urbé
- Department of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Michael J Clague
- Department of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
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13
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Sukhorukov V, Voronkov D, Baranich T, Mudzhiri N, Magnaeva A, Illarioshkin S. Impaired Mitophagy in Neurons and Glial Cells during Aging and Age-Related Disorders. Int J Mol Sci 2021; 22:10251. [PMID: 34638589 PMCID: PMC8508639 DOI: 10.3390/ijms221910251] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/18/2021] [Accepted: 09/22/2021] [Indexed: 12/17/2022] Open
Abstract
Aging is associated with a decline in cognitive function, which can partly be explained by the accumulation of damage to the brain cells over time. Neurons and glia undergo morphological and ultrastructure changes during aging. Over the past several years, it has become evident that at the cellular level, various hallmarks of an aging brain are closely related to mitophagy. The importance of mitochondria quality and quantity control through mitophagy is highlighted by the contribution that defects in mitochondria-autophagy crosstalk make to aging and age-related diseases. In this review, we analyze some of the more recent findings regarding the study of brain aging and neurodegeneration in the context of mitophagy. We discuss the data on the dynamics of selective autophagy in neurons and glial cells during aging and in the course of neurodegeneration, focusing on three mechanisms of mitophagy: non-receptor-mediated mitophagy, receptor-mediated mitophagy, and transcellular mitophagy. We review the role of mitophagy in neuronal/glial homeostasis and in the molecular pathogenesis of neurodegenerative disorders, such as Parkinson's disease, Alzheimer's disease, and other disorders. Common mechanisms of aging and neurodegeneration that are related to different mitophagy pathways provide a number of promising targets for potential therapeutic agents.
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Affiliation(s)
- Vladimir Sukhorukov
- Research Center of Neurology, Department for Brain Research, 125367 Moscow, Russia; (D.V.); (T.B.); (N.M.); (A.M.); (S.I.)
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14
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Bastien J, Menon S, Messa M, Nyfeler B. Molecular targets and approaches to restore autophagy and lysosomal capacity in neurodegenerative disorders. Mol Aspects Med 2021; 82:101018. [PMID: 34489092 DOI: 10.1016/j.mam.2021.101018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/18/2021] [Accepted: 08/25/2021] [Indexed: 01/18/2023]
Abstract
Autophagy is a catabolic process that promotes cellular fitness by clearing aggregated protein species, pathogens and damaged organelles through lysosomal degradation. The autophagic process is particularly important in the nervous system where post-mitotic neurons rely heavily on protein and organelle quality control in order to maintain cellular health throughout the lifetime of the organism. Alterations of autophagy and lysosomal function are hallmarks of various neurodegenerative disorders. In this review, we conceptualize some of the mechanistic and genetic evidence pointing towards autophagy and lysosomal dysfunction as a causal driver of neurodegeneration. Furthermore, we discuss rate-limiting pathway nodes and potential approaches to restore pathway activity, from autophagy initiation, cargo sequestration to lysosomal capacity.
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Affiliation(s)
- Julie Bastien
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Suchithra Menon
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Mirko Messa
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Beat Nyfeler
- Novartis Institutes for BioMedical Research, Basel, Switzerland.
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15
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Hepowit NL, Kolbe CC, Zelle SR, Latz E, MacGurn JA. Regulation of ubiquitin and ubiquitin-like modifiers by phosphorylation. FEBS J 2021; 289:4797-4810. [PMID: 34214249 PMCID: PMC9271371 DOI: 10.1111/febs.16101] [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: 04/19/2021] [Revised: 05/28/2021] [Accepted: 07/01/2021] [Indexed: 12/31/2022]
Abstract
The regulatory influence of ubiquitin is vast, encompassing all cellular processes, by virtue of its central roles in protein degradation, membrane trafficking, and cell signaling. But how does ubiquitin, a 76 amino acid peptide, carry out such diverse, complex functions in eukaryotic cells? Part of the answer is rooted in the high degree of complexity associated with ubiquitin polymers, which can be 'read' and processed differently depending on topology and cellular context. However, recent evidence indicates that post-translational modifications on ubiquitin itself enhance the complexity of the ubiquitin code. Here, we review recent discoveries related to the regulation of the ubiquitin code by phosphorylation. We summarize what is currently known about phosphorylation of ubiquitin at Ser65, Ser57, and Thr12, and we discuss the potential for phosphoregulation of ubiquitin at other sites. We also discuss accumulating evidence that ubiquitin-like modifiers, such as SUMO, are likewise regulated by phosphorylation. A complete understanding of these regulatory codes and their complex lexicon will require dissection of mechanisms that govern phosphorylation of ubiquitin and ubiquitin-like proteins, particularly in the context of cellular stress and disease.
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Affiliation(s)
- Nathaniel L Hepowit
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Carl-Christian Kolbe
- Institute of Innate Immunity, University Hospital Bonn, University of Bonn, Germany
| | - Sarah R Zelle
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Eicke Latz
- Institute of Innate Immunity, University Hospital Bonn, University of Bonn, Germany.,German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department of Infectious Diseases & Immunology, UMass Medical School, Worcester, MA, USA.,Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - Jason A MacGurn
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
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16
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Onishi M, Okamoto K. Mitochondrial clearance: mechanisms and roles in cellular fitness. FEBS Lett 2021; 595:1239-1263. [PMID: 33615465 DOI: 10.1002/1873-3468.14060] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 01/29/2021] [Accepted: 02/12/2021] [Indexed: 12/14/2022]
Abstract
Mitophagy is one of the selective autophagy pathways that catabolizes dysfunctional or superfluous mitochondria. Under mitophagy-inducing conditions, mitochondria are labeled with specific molecular landmarks that recruit the autophagy machinery to the surface of mitochondria, enclosed into autophagosomes, and delivered to lysosomes (vacuoles in yeast) for degradation. As damaged mitochondria are the major sources of reactive oxygen species, mitophagy is critical for mitochondrial quality control and cellular health. Moreover, appropriate control of mitochondrial quantity via mitophagy is vital for the energy supply-demand balance in cells and whole organisms, cell differentiation, and developmental programs. Thus, it seems conceivable that defects in mitophagy could elicit pleiotropic pathologies such as excess inflammation, tissue injury, neurodegeneration, and aging. In this review, we will focus on the molecular basis and physiological relevance of mitophagy, and potential of mitophagy as a therapeutic target to overcome such disorders.
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Affiliation(s)
- Mashun Onishi
- Laboratory of Mitochondrial Dynamics, Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Koji Okamoto
- Laboratory of Mitochondrial Dynamics, Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
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17
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Clark EH, Vázquez de la Torre A, Hoshikawa T, Briston T. Targeting mitophagy in Parkinson's disease. J Biol Chem 2021; 296:100209. [PMID: 33372898 PMCID: PMC7948953 DOI: 10.1074/jbc.rev120.014294] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 12/18/2020] [Accepted: 12/18/2020] [Indexed: 12/22/2022] Open
Abstract
The genetics and pathophysiology of Parkinson's disease (PD) strongly implicate mitochondria in disease aetiology. Elegant studies over the last two decades have elucidated complex molecular signaling governing the identification and removal of dysfunctional mitochondria from the cell, a process of mitochondrial quality control known as mitophagy. Mitochondrial deficits and specifically reduced mitophagy are evident in both sporadic and familial PD. Mendelian genetics attributes loss-of-function mutations in key mitophagy regulators PINK1 and Parkin to early-onset PD. Pharmacologically enhancing mitophagy and accelerating the removal of damaged mitochondria are of interest for developing a disease-modifying PD therapeutic. However, despite significant understanding of both PINK1-Parkin-dependent and -independent mitochondrial quality control pathways, the therapeutic potential of targeting mitophagy remains to be fully explored. Here, we provide a summary of the genetic evidence supporting the role for mitophagy failure as a pathogenic mechanism in PD. We assess the tractability of mitophagy pathways and prospects for drug discovery and consider intervention points for mitophagy enhancement. We explore the numerous hit molecules beginning to emerge from high-content/high-throughput screening as well as the biochemical and phenotypic assays that enabled these screens. The chemical and biological properties of these reference compounds suggest many could be used to interrogate and perturb mitochondrial biology to validate promising drug targets. Finally, we address key considerations and challenges in achieving preclinical proof-of-concept, including in vivo mitophagy reporter methodologies and disease models, as well as patient stratification and biomarker development for mitochondrial forms of the disease.
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Affiliation(s)
- Emily H Clark
- Hatfield Research Laboratories, Neurology Innovation Centre, Eisai Ltd, Hatfield, United Kingdom
| | | | - Tamaki Hoshikawa
- Hatfield Research Laboratories, Neurology Innovation Centre, Eisai Ltd, Hatfield, United Kingdom
| | - Thomas Briston
- Hatfield Research Laboratories, Neurology Innovation Centre, Eisai Ltd, Hatfield, United Kingdom.
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18
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Mitochondrial Dysfunction and Mitophagy in Parkinson's Disease: From Mechanism to Therapy. Trends Biochem Sci 2020; 46:329-343. [PMID: 33323315 DOI: 10.1016/j.tibs.2020.11.007] [Citation(s) in RCA: 226] [Impact Index Per Article: 56.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 12/12/2022]
Abstract
Mitochondrial dysfunction has been associated with neurodegeneration in Parkinson's disease (PD) for over 30 years. Despite this, the role of mitochondrial dysfunction as an initiator, propagator, or bystander remains undetermined. The discovery of the role of the PD familial genes PTEN-induced putative kinase 1 (PINK1) and parkin (PRKN) in mediating mitochondrial degradation (mitophagy) reaffirmed the importance of this process in PD aetiology. Recently, progress has been made in understanding the upstream and downstream regulators of canonical PINK1/parkin-mediated mitophagy, alongside noncanonical PINK1/parkin mitophagy, in response to mitochondrial damage. Progress has also been made in understanding the role of PD-associated genes, such as SNCA, LRRK2, and CHCHD2, in mitochondrial dysfunction and their overlap with sporadic PD (sPD), opening opportunities for therapeutically targeting mitochondria in PD.
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19
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Zachari M, Ktistakis NT. Mammalian Mitophagosome Formation: A Focus on the Early Signals and Steps. Front Cell Dev Biol 2020; 8:171. [PMID: 32258042 PMCID: PMC7093328 DOI: 10.3389/fcell.2020.00171] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 03/02/2020] [Indexed: 11/15/2022] Open
Abstract
Mitophagy, a conserved intracellular process by which mitochondria are eliminated via the autophagic machinery, is a quality control mechanism which facilitates maintenance of a functional mitochondrial network and cell homeostasis, making it a key process in development and longevity. Mitophagy has been linked to multiple human disorders, especially neurodegenerative diseases where the long-lived neurons are relying on clearance of old/damaged mitochondria to survive. During the past decade, the availability of novel tools to study mitophagy both in vitro and in vivo has significantly advanced our understanding of the molecular mechanisms governing this fundamental process in normal physiology and in various disease models. We here give an overview of the known mitophagy pathways and how they are induced, with a particular emphasis on the early events governing mitophagosome formation.
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Affiliation(s)
- Maria Zachari
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, United Kingdom
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