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Cardanho-Ramos C, Simões RA, Wang YZ, Faria-Pereira A, Bomba-Warczak E, Craessaerts K, Spinazzi M, Savas JN, Morais VA. Local mitochondrial replication in the periphery of neurons requires the eEF1A1 protein and thetranslation of nuclear-encoded proteins. iScience 2024; 27:109136. [PMID: 38510136 PMCID: PMC10951640 DOI: 10.1016/j.isci.2024.109136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 12/19/2023] [Accepted: 02/01/2024] [Indexed: 03/22/2024] Open
Abstract
In neurons, it is commonly assumed that mitochondrial replication only occurs in the cell body, after which the mitochondria must travel to the neuron's periphery. However, while mitochondrial DNA replication has been observed to occur away from the cell body, the specific mechanisms involved remain elusive. Using EdU-labelling in mouse primary neurons, we developed a tool to determine the mitochondrial replication rate. Taking of advantage of microfluidic devices, we confirmed that mitochondrial replication also occurs locally in the periphery of neurons. To achieve this, mitochondria require de novo nuclear-encoded, but not mitochondrial-encoded protein translation. Following a proteomic screen comparing synaptic with non-synaptic mitochondria, we identified two elongation factors - eEF1A1 and TUFM - that were upregulated in synaptic mitochondria. We found that mitochondrial replication is impaired upon the downregulation of eEF1A1, and this is particularly relevant in the periphery of neurons.
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Affiliation(s)
- Carlos Cardanho-Ramos
- Instituto de Medicina Molecular-João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Rúben Alves Simões
- Instituto de Medicina Molecular-João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Yi-Zhi Wang
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Andreia Faria-Pereira
- Instituto de Medicina Molecular-João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Ewa Bomba-Warczak
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Katleen Craessaerts
- VIB Center for Brain and Disease Research and KU Leuven, Department of Neurosciences, Leuven, Belgium
- Dementia Research Institute, University College London, London, UK
| | - Marco Spinazzi
- VIB Center for Brain and Disease Research and KU Leuven, Department of Neurosciences, Leuven, Belgium
- Dementia Research Institute, University College London, London, UK
- Neuromuscular Reference Center, Department of Neurology, Centre Hospitalier Universitaire d'Angers, Angers, France
| | - Jeffrey N. Savas
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Vanessa A. Morais
- Instituto de Medicina Molecular-João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
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2
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Huang T, Li H, Chen X, Chen D, Yu B, He J, Luo Y, Yan H, Zheng P, Yu J, Huang Z. Dietary Ferulic Acid Increases Endurance Capacity by Promoting Skeletal Muscle Oxidative Phenotype, Mitochondrial Function, and Antioxidant Capacity. Mol Nutr Food Res 2024; 68:e2200719. [PMID: 38193241 DOI: 10.1002/mnfr.202200719] [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: 10/22/2022] [Revised: 06/23/2023] [Indexed: 01/10/2024]
Abstract
SCOPE Endurance capacity is essential for endurance athletes' achievement and individuals' health. Nutritional supplements are a proven way to enhance endurance capacity. Previous studies have shown that ferulic acid (FA) enhances endurance capacity, but the underlying mechanism is unclear. The study is aimed to investigate the mechanism by which FA increases endurance capacity. METHODS AND RESULTS Forty mice are divided into control and 0.5% FA-supplemented groups, and an exhaustive swimming test demonstrates increased endurance capacity with FA supplementation. This study investigates the underlying mechanism for this effect of FA. Firstly, RT-PCR and western blot analysis find that FA increases the transformation from fast to slow muscle fiber. Additionally, adenosine triphosphate concentration, metabolic enzyme activity, and mitochondrial DNA analysis find that FA increases mitochondrial biogenesis and activates nuclear factor erythroid 2-related factor (NRF)1 signaling pathway in muscle. Besides, through antioxidant capacity analysis, this study finds that FA activates NRF2 signaling pathway and improves the antioxidant capacity in muscle. Moreover, inhibiting NRF2 eliminates FA's effect on muscle fiber transformation in C2C12 cells. CONCLUSION Our results suggest that FA increases endurance capacity by promoting skeletal muscle oxidative phenotype, mitochondrial function, and antioxidant capacity, which may be related to the NRF1 and NRF2 signaling pathways.
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Affiliation(s)
- Tengteng Huang
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Huawei Li
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Xiaoling Chen
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Daiwen Chen
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Bing Yu
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Jun He
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Yuheng Luo
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Hui Yan
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Ping Zheng
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Jie Yu
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
| | - Zhiqing Huang
- Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, Sichuan, 611130, P. R. China
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Chen M, Yan R, Luo J, Ning J, Zhou R, Ding L. The Role of PGC-1α-Mediated Mitochondrial Biogenesis in Neurons. Neurochem Res 2023:10.1007/s11064-023-03934-8. [PMID: 37097395 DOI: 10.1007/s11064-023-03934-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 03/28/2023] [Accepted: 03/31/2023] [Indexed: 04/26/2023]
Abstract
Neurons are highly dependent on mitochondrial ATP production and Ca2+ buffering. Neurons have unique compartmentalized anatomy and energy requirements, and each compartment requires continuously renewed mitochondria to maintain neuronal survival and activity. Peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) is a key factor in the regulation of mitochondrial biogenesis. It is widely accepted that mitochondria are synthesized in the cell body and transported via axons to the distal end. However, axonal mitochondrial biogenesis is necessary to maintain axonal bioenergy supply and mitochondrial density due to limitations in mitochondrial axonal transport rate and mitochondrial protein lifespan. In addition, impaired mitochondrial biogenesis leading to inadequate energy supply and neuronal damage has been observed in neurological disorders. In this review, we focus on the sites where mitochondrial biogenesis occurs in neurons and the mechanisms by which it maintains axonal mitochondrial density. Finally, we summarize several neurological disorders in which mitochondrial biogenesis is affected.
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Affiliation(s)
- Mengjie Chen
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Ruyu Yan
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Jiansheng Luo
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Jiaqi Ning
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Ruiling Zhou
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Lingling Ding
- Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China.
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4
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Vargas JNS, Hamasaki M, Kawabata T, Youle RJ, Yoshimori T. The mechanisms and roles of selective autophagy in mammals. Nat Rev Mol Cell Biol 2023; 24:167-185. [PMID: 36302887 DOI: 10.1038/s41580-022-00542-2] [Citation(s) in RCA: 207] [Impact Index Per Article: 207.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2022] [Indexed: 11/09/2022]
Abstract
Autophagy is a process that targets various intracellular elements for degradation. Autophagy can be non-selective - associated with the indiscriminate engulfment of cytosolic components - occurring in response to nutrient starvation and is commonly referred to as bulk autophagy. By contrast, selective autophagy degrades specific targets, such as damaged organelles (mitophagy, lysophagy, ER-phagy, ribophagy), aggregated proteins (aggrephagy) or invading bacteria (xenophagy), thereby being importantly involved in cellular quality control. Hence, not surprisingly, aberrant selective autophagy has been associated with various human pathologies, prominently including neurodegeneration and infection. In recent years, considerable progress has been made in understanding mechanisms governing selective cargo engulfment in mammals, including the identification of ubiquitin-dependent selective autophagy receptors such as p62, NBR1, OPTN and NDP52, which can bind cargo and ubiquitin simultaneously to initiate pathways leading to autophagy initiation and membrane recruitment. This progress opens the prospects for enhancing selective autophagy pathways to boost cellular quality control capabilities and alleviate pathology.
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Affiliation(s)
- Jose Norberto S Vargas
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, UK
- UK Dementia Research Institute, University College London, London, UK
- Biochemistry Section, Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Maho Hamasaki
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan.
- Department of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan.
| | - Tsuyoshi Kawabata
- Department of Stem Cell Biology, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan
| | - Richard J Youle
- Biochemistry Section, Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
| | - Tamotsu Yoshimori
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan.
- Department of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan.
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5
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Altered transcriptome-proteome coupling indicates aberrant proteostasis in Parkinson's disease. iScience 2023; 26:105925. [PMID: 36711240 PMCID: PMC9874017 DOI: 10.1016/j.isci.2023.105925] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/02/2022] [Accepted: 01/03/2023] [Indexed: 01/06/2023] Open
Abstract
Aberrant proteostasis is thought to be implicated in Parkinson's disease (PD), but patient-derived evidence is scant. We hypothesized that impaired proteostasis is reflected as altered transcriptome-proteome correlation in the PD brain. We integrated transcriptomic and proteomic data from prefrontal cortex of PD patients and young and aged controls to assess RNA-protein correlations across samples. The aged brain showed a genome-wide decrease in mRNA-protein correlation. Genes encoding synaptic vesicle proteins showed negative correlations, likely reflecting spatial separation of mRNA and protein into soma and synapses. PD showed a broader transcriptome-proteome decoupling, consistent with a proteome-wide decline in proteostasis. Genes showing negative correlation in PD were enriched for proteasome subunits, indicating accentuated spatial separation of transcript and protein in PD neurons. In addition, PD showed positive correlations for mitochondrial respiratory chain genes, suggesting a tighter regulation in the face of mitochondrial dysfunction. Our results support the hypothesis that aberrant proteasomal function is implicated in PD pathogenesis.
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6
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Gale JR, Gedeon JY, Donnelly CJ, Gold MS. Local translation in primary afferents and its contribution to pain. Pain 2022; 163:2302-2314. [PMID: 35438669 PMCID: PMC9579217 DOI: 10.1097/j.pain.0000000000002658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 04/08/2022] [Indexed: 02/06/2023]
Abstract
ABSTRACT Chronic pain remains a significant problem due to its prevalence, impact, and limited therapeutic options. Progress in addressing chronic pain is dependent on a better understanding of underlying mechanisms. Although the available evidence suggests that changes within the central nervous system contribute to the initiation and maintenance of chronic pain, it also suggests that the primary afferent plays a critical role in all phases of the manifestation of chronic pain in most of those who suffer. Most notable among the changes in primary afferents is an increase in excitability or sensitization. A number of mechanisms have been identified that contribute to primary afferent sensitization with evidence for both increases in pronociceptive signaling molecules, such as voltage-gated sodium channels, and decreases in antinociceptive signaling molecules, such as voltage-dependent or calcium-dependent potassium channels. Furthermore, these changes in signaling molecules seem to reflect changes in gene expression as well as posttranslational processing. A mechanism of sensitization that has received far less attention, however, is the local or axonal translation of these signaling molecules. A growing body of evidence indicates that this process not only is dynamically regulated but also contributes to the initiation and maintenance of chronic pain. Here, we review the biology of local translation in primary afferents and its relevance to pain pathobiology.
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Affiliation(s)
- Jenna R Gale
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Jeremy Y Gedeon
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | | | - Michael S Gold
- Corresponding author: Michael S Gold, PhD, Department of Neurobiology, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15213, P: 412-383-5367,
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7
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Hees JT, Harbauer AB. Metabolic Regulation of Mitochondrial Protein Biogenesis from a Neuronal Perspective. Biomolecules 2022; 12:1595. [PMID: 36358945 PMCID: PMC9687362 DOI: 10.3390/biom12111595] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/24/2022] [Accepted: 10/26/2022] [Indexed: 09/29/2023] Open
Abstract
Neurons critically depend on mitochondria for ATP production and Ca2+ buffering. They are highly compartmentalized cells and therefore a finely tuned mitochondrial network constantly adapting to the local requirements is necessary. For neuronal maintenance, old or damaged mitochondria need to be degraded, while the functional mitochondrial pool needs to be replenished with freshly synthesized components. Mitochondrial biogenesis is known to be primarily regulated via the PGC-1α-NRF1/2-TFAM pathway at the transcriptional level. However, while transcriptional regulation of mitochondrial genes can change the global mitochondrial content in neurons, it does not explain how a morphologically complex cell such as a neuron adapts to local differences in mitochondrial demand. In this review, we discuss regulatory mechanisms controlling mitochondrial biogenesis thereby making a case for differential regulation at the transcriptional and translational level. In neurons, additional regulation can occur due to the axonal localization of mRNAs encoding mitochondrial proteins. Hitchhiking of mRNAs on organelles including mitochondria as well as contact site formation between mitochondria and endolysosomes are required for local mitochondrial biogenesis in axons linking defects in any of these organelles to the mitochondrial dysfunction seen in various neurological disorders.
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Affiliation(s)
- Jara Tabitha Hees
- TUM Medical Graduate Center, Technical University of Munich, 81675 Munich, Germany
- Max Planck Institute for Biological Intelligence, in Foundation, 82152 Planegg-Martinsried, Germany
| | - Angelika Bettina Harbauer
- Max Planck Institute for Biological Intelligence, in Foundation, 82152 Planegg-Martinsried, Germany
- Institute of Neuronal Cell Biology, Technical University of Munich, 80802 Munich, Germany
- Munich Cluster for Systems Neurology, 81377 Munich, Germany
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8
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Cohen B, Altman T, Golani-Armon A, Savulescu AF, Ibraheem A, Mhlanga MM, Perlson E, Arava YS. The nuclear encoded Cox7c mRNA co-transport with mitochondria along axons via coding-region dependent mechanism. J Cell Sci 2022; 135:276008. [PMID: 35833493 PMCID: PMC9481926 DOI: 10.1242/jcs.259436] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 07/07/2022] [Indexed: 11/20/2022] Open
Abstract
Nuclear-encoded mitochondrial protein mRNAs have been found to be localized and locally translated within neuronal processes. However, the mechanism of transport for those mRNAs to distal locations is not fully understood. Here, we describe axonal co-transport of Cox7c with mitochondria. Fractionation analysis and single-molecule fluorescence in situ hybridization (smFISH) assay revealed that endogenous mRNA encoding Cox7c was preferentially associated with mitochondria in a mouse neuronal cell line and within mouse primary motor neuron axons, whereas other mRNAs that do not encode mitochondrial protein were much less associated. Live-cell imaging of MS2-tagged Cox7c mRNA further confirmed the preferential colocalization and co-transport of Cox7c mRNA with mitochondria in motor neuron axons. Intriguingly, the coding region, rather than the 3′ untranslated region (UTR), was the key domain for the co-transport. Our results reveal that Cox7c mRNA can be transported with mitochondria along significant distances and that its coding region is a major recognition feature. This is consistent with the idea that mitochondria can play a vital role in spatial regulation of the axonal transcriptome at distant neuronal sites. Summary: Biochemical and live imaging analyses show that in mouse axons, Cox7c mRNA is associated and transported with mitochondria. Mutational analysis identifies mRNA domains essential for co-transport.
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Affiliation(s)
- Bar Cohen
- Faculty of Biology, Technion - Israel Institute of Technology, Israel
| | - Topaz Altman
- Sackler Faculty of Medicine, Tel Aviv University, Israel
| | - Adi Golani-Armon
- Faculty of Biology, Technion - Israel Institute of Technology, Israel.,Faculty of Nanosciences and Nanoengineering, Technion - Israel Institute of Technology, Israel
| | - Anca F Savulescu
- Division of Chemical, Systems & Synthetic Biology, Department of Integrative Biomedical Sciences, Faculty of Health Sciences, Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Amjd Ibraheem
- Sackler Faculty of Medicine, Tel Aviv University, Israel
| | - Musa M Mhlanga
- Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands.,Epigenomics & Single Cell Biophysics Group, Department of Cell Biology, FNWI, Radboud University, 6525 GA Nijmegen, the Netherlands.,Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Eran Perlson
- Sackler Faculty of Medicine, Tel Aviv University, Israel
| | - Yoav S Arava
- Faculty of Biology, Technion - Israel Institute of Technology, Israel
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9
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Vargas JNS, Sleigh JN, Schiavo G. Coupling axonal mRNA transport and local translation to organelle maintenance and function. Curr Opin Cell Biol 2022; 74:97-103. [PMID: 35220080 PMCID: PMC10477965 DOI: 10.1016/j.ceb.2022.01.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/14/2022] [Accepted: 01/22/2022] [Indexed: 12/14/2022]
Abstract
Neuronal homeostasis requires the transport of various organelles to distal compartments and defects in this process lead to neurological disorders. Although several mechanisms for the delivery of organelles to axons and dendrites have been elucidated, exactly how this process is orchestrated is not well-understood. In this review, we discuss the recent literature supporting a novel paradigm - the co-shuttling of mRNAs with different membrane-bound organelles. This model postulates that the tethering of ribonucleoprotein complexes to endolysosomes and mitochondria allows for the spatiotemporal coupling of organelle transport and the delivery of transcripts to axons. Subcellular translation of these "hitchhiking" transcripts may thus provide a proximal source of proteins required for the maintenance and function of organelles in axons.
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Affiliation(s)
- Jose Norberto S Vargas
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, UK; UCL Queen Square Motor Neuron Disease Centre, UCL Queen Square Institute of Neurology, University College London, London, UK; UK Dementia Research Institute, University College London, London, UK
| | - James N Sleigh
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, UK; UCL Queen Square Motor Neuron Disease Centre, UCL Queen Square Institute of Neurology, University College London, London, UK; UK Dementia Research Institute, University College London, London, UK
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, University College London, London, UK; UCL Queen Square Motor Neuron Disease Centre, UCL Queen Square Institute of Neurology, University College London, London, UK; UK Dementia Research Institute, University College London, London, UK.
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10
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Hobson BD, Kong L, Angelo MF, Lieberman OJ, Mosharov EV, Herzog E, Sulzer D, Sims PA. Subcellular and regional localization of mRNA translation in midbrain dopamine neurons. Cell Rep 2022; 38:110208. [PMID: 35021090 PMCID: PMC8844886 DOI: 10.1016/j.celrep.2021.110208] [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: 07/30/2021] [Revised: 10/25/2021] [Accepted: 12/13/2021] [Indexed: 12/12/2022] Open
Abstract
Midbrain dopaminergic (mDA) neurons exhibit extensive dendritic and axonal arborizations, but local protein synthesis is not characterized in these neurons. Here, we investigate messenger RNA (mRNA) localization and translation in mDA neuronal axons and dendrites, both of which release dopamine (DA). Using highly sensitive ribosome-bound RNA sequencing and imaging approaches, we find no evidence for mRNA translation in mDA axons. In contrast, mDA neuronal dendrites in the substantia nigra pars reticulata (SNr) contain ribosomes and mRNAs encoding the major components of DA synthesis, release, and reuptake machinery. Surprisingly, we also observe dendritic localization of mRNAs encoding synaptic vesicle-related proteins, including those involved in exocytic fusion. Our results are consistent with a role for local translation in the regulation of DA release from dendrites, but not from axons. Our translatome data define a molecular signature of sparse mDA neurons in the SNr, including the enrichment of Atp2a3/SERCA3, an atypical ER calcium pump. Local translation regulates the subcellular proteome in neurons but has not been characterized in midbrain dopamine neurons, cells with large dendrites and axonal arborizations. Hobson et al. investigate messenger RNA localization and translation in midbrain dopamine neurons in the mouse brain, finding ribosomes and dopaminergic mRNAs in dendrites, but not axons.
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Affiliation(s)
- Benjamin D Hobson
- Department of Systems Biology, Columbia University Irving Medical Center, New York 10032, NY, USA; Medical Scientist Training Program, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Linghao Kong
- Department of Systems Biology, Columbia University Irving Medical Center, New York 10032, NY, USA
| | - Maria Florencia Angelo
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France; Interdisciplinary Institute for Neuroscience, CNRS UMR 5297, Bordeaux, France
| | - Ori J Lieberman
- Medical Scientist Training Program, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Eugene V Mosharov
- Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA; Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY 10032, USA
| | - Etienne Herzog
- Interdisciplinary Institute for Neuroscience, Université de Bordeaux, Bordeaux, France; Interdisciplinary Institute for Neuroscience, CNRS UMR 5297, Bordeaux, France.
| | - David Sulzer
- Department of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Psychiatry, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Pharmacology, Columbia University Irving Medical Center, New York, NY 10032, USA; Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY 10032, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA.
| | - Peter A Sims
- Department of Systems Biology, Columbia University Irving Medical Center, New York 10032, NY, USA; Department of Biochemistry & Molecular Biophysics, Columbia University Irving Medical Center, New York, NY 10032, USA; Sulzberger Columbia Genome Center, Columbia University Irving Medical Center, New York, NY 10032, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA.
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11
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mtIF3 is locally translated in axons and regulates mitochondrial translation for axonal growth. BMC Biol 2022; 20:12. [PMID: 34996455 PMCID: PMC8742369 DOI: 10.1186/s12915-021-01215-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 11/09/2021] [Indexed: 11/13/2022] Open
Abstract
Background The establishment and maintenance of functional neural connections relies on appropriate distribution and localization of mitochondria in neurites, as these organelles provide essential energy and metabolites. In particular, mitochondria are transported to axons and support local energy production to maintain energy-demanding neuronal processes including axon branching, growth, and regeneration. Additionally, local protein synthesis is required for structural and functional changes in axons, with nuclear-encoded mitochondrial mRNAs having been found localized in axons. However, it remains unclear whether these mRNAs are locally translated and whether the potential translated mitochondrial proteins are involved in the regulation of mitochondrial functions in axons. Here, we aim to further understand the purpose of such compartmentalization by focusing on the role of mitochondrial initiation factor 3 (mtIF3), whose nuclear-encoded transcripts have been shown to be present in axonal growth cones. Results We demonstrate that brain-derived neurotrophic factor (BDNF) induces local translation of mtIF3 mRNA in axonal growth cones. Subsequently, mtIF3 protein is translocated into axonal mitochondria and promotes mitochondrial translation as assessed by our newly developed bimolecular fluorescence complementation sensor for the assembly of mitochondrial ribosomes. We further show that BDNF-induced axonal growth requires mtIF3-dependent mitochondrial translation in distal axons. Conclusion We describe a previously unknown function of mitochondrial initiation factor 3 (mtIF3) in axonal protein synthesis and development. These findings provide insight into the way neurons adaptively control mitochondrial physiology and axonal development via local mtIF3 translation. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01215-w.
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12
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Mitochondrial Biogenesis in Neurons: How and Where. Int J Mol Sci 2021; 22:ijms222313059. [PMID: 34884861 PMCID: PMC8657637 DOI: 10.3390/ijms222313059] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 11/27/2021] [Accepted: 11/29/2021] [Indexed: 11/27/2022] Open
Abstract
Neurons rely mostly on mitochondria for the production of ATP and Ca2+ homeostasis. As sub-compartmentalized cells, they have different pools of mitochondria in each compartment that are maintained by a constant mitochondrial turnover. It is assumed that most mitochondria are generated in the cell body and then travel to the synapse to exert their functions. Once damaged, mitochondria have to travel back to the cell body for degradation. However, in long cells, like motor neurons, this constant travel back and forth is not an energetically favourable process, thus mitochondrial biogenesis must also occur at the periphery. Ca2+ and ATP levels are the main triggers for mitochondrial biogenesis in the cell body, in a mechanism dependent on the Peroxisome-proliferator-activated γ co-activator-1α-nuclear respiration factors 1 and 2-mitochondrial transcription factor A (PGC-1α-NRF-1/2-TFAM) pathway. However, even though of extreme importance, very little is known about the mechanisms promoting mitochondrial biogenesis away from the cell body. In this review, we bring forward the evoked mechanisms that are at play for mitochondrial biogenesis in the cell body and periphery. Moreover, we postulate that mitochondrial biogenesis may vary locally within the same neuron, and we build upon the hypotheses that, in the periphery, local protein synthesis is responsible for giving all the machinery required for mitochondria to replicate themselves.
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13
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Li L, Yu J, Ji SJ. Axonal mRNA localization and translation: local events with broad roles. Cell Mol Life Sci 2021; 78:7379-7395. [PMID: 34698881 PMCID: PMC11072051 DOI: 10.1007/s00018-021-03995-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 09/17/2021] [Accepted: 10/14/2021] [Indexed: 12/19/2022]
Abstract
Messenger RNA (mRNA) can be transported and targeted to different subcellular compartments and locally translated. Local translation is an evolutionally conserved mechanism that in mammals, provides an important tool to exquisitely regulate the subcellular proteome in different cell types, including neurons. Local translation in axons is involved in processes such as neuronal development, function, plasticity, and diseases. Here, we summarize the current progress on axonal mRNA transport and translation. We focus on the regulatory mechanisms governing how mRNAs are transported to axons and how they are locally translated in axons. We discuss the roles of axonally synthesized proteins, which either function locally in axons, or are retrogradely trafficked back to soma to achieve neuron-wide gene regulation. We also examine local translation in neurological diseases. Finally, we give a critical perspective on the remaining questions that could be answered to uncover the fundamental rules governing local translation, and discuss how this could lead to new therapeutic targets for neurological diseases.
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Affiliation(s)
- Lichao Li
- School of Life Sciences, Department of Biology, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Brain Research Center, Southern University of Science and Technology, Shenzhen, 518055, Guangdong, China
| | - Jun Yu
- School of Life Sciences, Department of Biology, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Brain Research Center, Southern University of Science and Technology, Shenzhen, 518055, Guangdong, China
| | - Sheng-Jian Ji
- School of Life Sciences, Department of Biology, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Brain Research Center, Southern University of Science and Technology, Shenzhen, 518055, Guangdong, China.
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14
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Smith TP, Sahoo PK, Kar AN, Twiss JL. Intra-axonal mechanisms driving axon regeneration. Brain Res 2020; 1740:146864. [PMID: 32360100 DOI: 10.1016/j.brainres.2020.146864] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/27/2022]
Abstract
Traumatic injury to the peripheral and central nervous systems very often causes axotomy, where an axon loses connections with its target resulting in loss of function. The axon segments distal to the injury site lose connection with the cell body and degenerate. Axotomized neurons in the periphery can spontaneously mount a regenerative response and reconnect to their denervated target tissues, though this is rarely complete in humans. In contrast, spontaneous regeneration rarely occurs after axotomy in the spinal cord and brain. Here, we concentrate on the mechanisms underlying this spontaneous regeneration in the peripheral nervous system, focusing on events initiated from the axon that support regenerative growth. We contrast this with what is known for axonal injury responses in the central nervous system. Considering the neuropathy focus of this special issue, we further draw parallels and distinctions between the injury-response mechanisms that initiate regenerative gene expression programs and those that are known to trigger axon degeneration.
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Affiliation(s)
- Terika P Smith
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Pabitra K Sahoo
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Amar N Kar
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Jeffery L Twiss
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA.
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15
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Ge P, Dawson VL, Dawson TM. PINK1 and Parkin mitochondrial quality control: a source of regional vulnerability in Parkinson's disease. Mol Neurodegener 2020; 15:20. [PMID: 32169097 PMCID: PMC7071653 DOI: 10.1186/s13024-020-00367-7] [Citation(s) in RCA: 237] [Impact Index Per Article: 59.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/13/2020] [Indexed: 02/06/2023] Open
Abstract
That certain cell types in the central nervous system are more likely to undergo neurodegeneration in Parkinson's disease is a widely appreciated but poorly understood phenomenon. Many vulnerable subpopulations, including dopamine neurons in the substantia nigra pars compacta, have a shared phenotype of large, widely distributed axonal networks, dense synaptic connections, and high basal levels of neural activity. These features come at substantial bioenergetic cost, suggesting that these neurons experience a high degree of mitochondrial stress. In such a context, mechanisms of mitochondrial quality control play an especially important role in maintaining neuronal survival. In this review, we focus on understanding the unique challenges faced by the mitochondria in neurons vulnerable to neurodegeneration in Parkinson's and summarize evidence that mitochondrial dysfunction contributes to disease pathogenesis and to cell death in these subpopulations. We then review mechanisms of mitochondrial quality control mediated by activation of PINK1 and Parkin, two genes that carry mutations associated with autosomal recessive Parkinson's disease. We conclude by pinpointing critical gaps in our knowledge of PINK1 and Parkin function, and propose that understanding the connection between the mechanisms of sporadic Parkinson's and defects in mitochondrial quality control will lead us to greater insights into the question of selective vulnerability.
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Affiliation(s)
- Preston Ge
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Department of Physiology, Solomon H. Snyder Department of Neuroscience, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 733 North Broadway, Suite 731, Baltimore, MD 21205 USA
- Adrienne Helis Malvin Medical Research Foundation, New Orleans, LA 70130 USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130 USA
- Present address: Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
- Present address: Picower Institute for Learning and Memory, Cambridge, MA 02139 USA
- Present address: Harvard-MIT MD/PhD Program, Harvard Medical School, Boston, MA 02115 USA
| | - Valina L. Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Department of Physiology, Solomon H. Snyder Department of Neuroscience, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 733 North Broadway, Suite 731, Baltimore, MD 21205 USA
- Adrienne Helis Malvin Medical Research Foundation, New Orleans, LA 70130 USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130 USA
| | - Ted M. Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Department of Physiology, Solomon H. Snyder Department of Neuroscience, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 733 North Broadway, Suite 731, Baltimore, MD 21205 USA
- Adrienne Helis Malvin Medical Research Foundation, New Orleans, LA 70130 USA
- Diana Helis Henry Medical Research Foundation, New Orleans, LA 70130 USA
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16
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Pushpalatha KV, Besse F. Local Translation in Axons: When Membraneless RNP Granules Meet Membrane-Bound Organelles. Front Mol Biosci 2019; 6:129. [PMID: 31824961 PMCID: PMC6882739 DOI: 10.3389/fmolb.2019.00129] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/06/2019] [Indexed: 12/14/2022] Open
Abstract
Eukaryotic cell compartmentalization relies on long-known membrane-delimited organelles, as well as on more recently discovered membraneless macromolecular condensates. How these two types of organelles interact to regulate cellular functions is still largely unclear. In this review, we highlight how membraneless ribonucleoprotein (RNP) organelles, enriched in RNAs and associated regulatory proteins, cooperate with membrane-bound organelles for tight spatio-temporal control of gene expression in the axons of neuronal cells. Specifically, we present recent evidence that motile membrane-bound organelles are used as vehicles by RNP cargoes, promoting the long-range transport of mRNA molecules to distal axons. As demonstrated by recent work, membrane-bound organelles also promote local protein synthesis, by serving as platforms for the local translation of mRNAs recruited to their outer surface. Furthermore, dynamic and specific association between RNP cargoes and membrane-bound organelles is mediated by bi-partite adapter molecules that interact with both types of organelles selectively, in a regulated-manner. Maintaining such a dynamic interplay is critical, as alterations in this process are linked to neurodegenerative diseases. Together, emerging studies thus point to the coordination of membrane-bound and membraneless organelles as an organizing principle underlying local cellular responses.
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Affiliation(s)
| | - Florence Besse
- Université Côte d'Azur, CNRS, Inserm, Institut de Biology Valrose, Nice, France
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17
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Farris S, Ward JM, Carstens KE, Samadi M, Wang Y, Dudek SM. Hippocampal Subregions Express Distinct Dendritic Transcriptomes that Reveal Differences in Mitochondrial Function in CA2. Cell Rep 2019; 29:522-539.e6. [PMID: 31597108 PMCID: PMC6894405 DOI: 10.1016/j.celrep.2019.08.093] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/15/2019] [Accepted: 08/27/2019] [Indexed: 12/15/2022] Open
Abstract
RNA localization is one mechanism neurons use to spatially and temporally regulate gene expression at synapses. Here, we test the hypothesis that cells exhibiting distinct forms of synaptic plasticity will have differences in dendritically localized RNAs. Indeed, we discover that each major subregion of the adult mouse hippocampus expresses a unique complement of dendritic RNAs. Specifically, we describe more than 1,000 differentially expressed dendritic RNAs, suggesting that RNA localization and local translation are regulated in a cell type-specific manner. Furthermore, by focusing Gene Ontology analyses on the plasticity-resistant CA2, we identify an enrichment of mitochondria-associated pathways in CA2 cell bodies and dendrites, and we provide functional evidence that these pathways differentially influence plasticity and mitochondrial respiration in CA2. These data indicate that differences in dendritic transcriptomes may regulate cell type-specific properties important for learning and memory and may influence region-specific differences in disease pathology.
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Affiliation(s)
- Shannon Farris
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA
| | - James M Ward
- Integrative Bioinformatics, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA
| | - Kelly E Carstens
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA
| | - Mahsa Samadi
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA
| | - Yu Wang
- Cellular and Molecular Pathology, National Toxicology Program, NIH, Research Triangle Park, NC 27709, USA
| | - Serena M Dudek
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA.
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18
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Mandal A, Drerup CM. Axonal Transport and Mitochondrial Function in Neurons. Front Cell Neurosci 2019; 13:373. [PMID: 31447650 PMCID: PMC6696875 DOI: 10.3389/fncel.2019.00373] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/30/2019] [Indexed: 12/31/2022] Open
Abstract
The complex and elaborate architecture of a neuron poses a great challenge to the cellular machinery which localizes proteins and organelles, such as mitochondria, to necessary locations. Proper mitochondrial localization in neurons is particularly important as this organelle provides energy and metabolites essential to form and maintain functional neural connections. Consequently, maintenance of a healthy pool of mitochondria and removal of damaged organelles are essential for neuronal homeostasis. Long distance transport of the organelle itself as well as components necessary for maintaining mitochondria in distal compartments are important for a constant supply of healthy mitochondria at the right time and place. Accordingly, many neurodegenerative diseases have been associated with mitochondrial abnormalities. Here, we review our current understanding on transport-dependent mechanisms that regulate mitochondrial replenishment. We focus on axonal transport and import of mRNAs and proteins destined for mitochondria as well as mitochondrial fusion and fission to maintain mitochondrial homeostasis in distal compartments of the neuron.
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Affiliation(s)
- Amrita Mandal
- Unit on Neuronal Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Catherine M Drerup
- Unit on Neuronal Cell Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
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19
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Farias J, Sotelo JR, Sotelo‐Silveira J. Toward Axonal System Biology: Genome Wide Views of Local mRNA Translation. Proteomics 2019; 19:e1900054. [DOI: 10.1002/pmic.201900054] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/12/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Joaquina Farias
- Departamento de Proteínas y Ácidos NucleicosInstituto de Investigaciones Biológicas Clemente Estable Montevideo CP 11600 Uruguay
- Departamento de GenómicaInstituto de Investigaciones Biológicas Clemente Estable Montevideo CP 11600 Uruguay
| | - José Roberto Sotelo
- Departamento de Proteínas y Ácidos NucleicosInstituto de Investigaciones Biológicas Clemente Estable Montevideo CP 11600 Uruguay
| | - José Sotelo‐Silveira
- Departamento de GenómicaInstituto de Investigaciones Biológicas Clemente Estable Montevideo CP 11600 Uruguay
- Sección Biología CelularFacultad de Ciencias, Universidad de la República Montevideo CP 11400 Uruguay
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20
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Corti O. Neuronal Mitophagy: Lessons from a Pathway Linked to Parkinson's Disease. Neurotox Res 2019; 36:292-305. [PMID: 31102068 DOI: 10.1007/s12640-019-00060-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 04/17/2019] [Accepted: 05/06/2019] [Indexed: 02/06/2023]
Abstract
Neurons are specialized cells with complex and extended architecture and high energy requirements. Energy in the form of adenosine triphosphate, produced essentially by mitochondrial respiration, is necessary to preserve neuronal morphology, maintain resting potential, fire action potentials, and ensure neurotransmission. Pools of functional mitochondria are required in all neuronal compartments, including cell body and dendrites, nodes of Ranvier, growth cones, axons, and synapses. The mechanisms by which old or damaged mitochondria are removed and replaced in neurons remain to be fully understood. Mitophagy has gained considerable interest since the discovery of familial forms of Parkinson's disease caused by dysfunction of PINK1 and Parkin, two multifunctional proteins cooperating in the regulation of this process. Over the past 10 years, the molecular mechanisms by which PINK1 and Parkin jointly promote the degradation of defective mitochondria by autophagy have been dissected. However, our understanding of the relevance of mitophagy to mitochondrial homeostasis in neurons remains poor. Insight has been recently gained thanks to the development of fluorescent reporter systems for tracking mitochondria in the acidic compartment of the lysosome. Using these tools, mitophagy events have been visualized in primary neurons in culture and in vivo, under basal conditions and in response to toxic insults. Despite these advances, whether PINK1 and Parkin play a major role in promoting neuronal mitophagy under physiological conditions in adult animals and during aging remains a matter of debate. Future studies will have to clarify in how far dysfunction of neuronal mitophagy is central to the pathophysiology of Parkinson's disease.
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Affiliation(s)
- Olga Corti
- Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France.
- Inserm, U1127, F-75013, Paris, France.
- CNRS, UMR 7225, F-75013, Paris, France.
- Sorbonne Universités, F-75013, Paris, France.
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21
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Evidence for Compartmentalized Axonal Mitochondrial Biogenesis: Mitochondrial DNA Replication Increases in Distal Axons As an Early Response to Parkinson's Disease-Relevant Stress. J Neurosci 2018; 38:7505-7515. [PMID: 30030401 DOI: 10.1523/jneurosci.0541-18.2018] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 06/19/2018] [Accepted: 07/07/2018] [Indexed: 12/18/2022] Open
Abstract
Dysregulation of mitochondrial biogenesis is implicated in the pathogenesis of neurodegenerative diseases such as Parkinson's disease (PD). However, it is not clear how mitochondrial biogenesis is regulated in neurons, with their unique compartmentalized anatomy and energetic demands. This is particularly relevant in PD because selectively vulnerable neurons feature long, highly arborized axons where degeneration initiates. We previously found that exposure of neurons to chronic, sublethal doses of rotenone, a complex I inhibitor linked to PD, causes early increases in mitochondrial density specifically in distal axons, suggesting possible upregulation of mitochondrial biogenesis within axons. Here, we directly evaluated for evidence of mitochondrial biogenesis in distal axons and examined whether PD-relevant stress causes compartmentalized alterations. Using BrdU labeling and imaging to quantify replicating mitochondrial DNA (mtDNA) in primary rat neurons (pooled from both sexes), we provide evidence of mtDNA replication in axons along with cell bodies and proximal dendrites. We found that exposure to chronic, sublethal rotenone increases mtDNA replication first in neurites and later extending to cell bodies, complementing our mitochondrial density data. Further, isolating axons from cell bodies and dendrites, we discovered that rotenone exposure upregulates mtDNA replication in distal axons. Utilizing superresolution stimulated emission depletion (STED) imaging, we identified mtDNA replication at sites of mitochondrial-endoplasmic reticulum contacts in axons. Our evidence suggests that mitochondrial biogenesis occurs not only in cell bodies, but also in distal axons, and is altered under PD-relevant stress conditions in an anatomically compartmentalized manner. We hypothesize that this contributes to vulnerability in neurodegenerative diseases.SIGNIFICANCE STATEMENT Mitochondrial biogenesis is crucial for maintaining mitochondrial and cellular health and has been linked to neurodegenerative disease pathogenesis. However, regulation of this process is poorly understood in CNS neurons, which rely on mitochondrial function for survival. Our findings offer fundamental insight into these regulatory mechanisms by demonstrating that replication of mitochondrial DNA, an essential precursor for biogenesis, can occur in distal regions of CNS neuron axons independent of the soma. Further, this process is upregulated specifically in axons as an early response to neurodegeneration-relevant stress. This is the first demonstration of the compartmentalized regulation of CNS neuronal mitochondrial biogenesis in response to stress and may prove a useful target in development of therapeutic strategies for neurodegenerative disease.
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22
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Cioni JM, Koppers M, Holt CE. Molecular control of local translation in axon development and maintenance. Curr Opin Neurobiol 2018; 51:86-94. [PMID: 29549711 DOI: 10.1016/j.conb.2018.02.025] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 02/24/2018] [Accepted: 02/26/2018] [Indexed: 11/27/2022]
Abstract
The tips of axons are often far away from the cell soma where most proteins are synthesized. Recent work has revealed that axonal mRNA transport and localised translation are key regulatory mechanisms that allow these distant outposts of the cell to respond rapidly to extrinsic factors and maintain axonal homeostasis. Here, we review recent evidence pointing to an increasingly broad role for local protein synthesis in controlling axon shape, synaptogenesis and axon survival by regulating diverse cellular processes such as vesicle trafficking, cytoskeletal remodelling and mitochondrial integrity. We further highlight current research on the regulatory mechanisms that coordinate the localization and translation of functionally linked mRNAs in axons.
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Affiliation(s)
- Jean-Michel Cioni
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Max Koppers
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Christine E Holt
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK.
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23
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A compartmentalized culture device for studying the axons of CNS neurons. Anal Biochem 2017; 539:11-21. [DOI: 10.1016/j.ab.2017.09.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/25/2017] [Accepted: 09/20/2017] [Indexed: 12/27/2022]
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24
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Vincent T, Vingadassalon A, Ubrig E, Azeredo K, Srour O, Cognat V, Graindorge S, Salinas T, Maréchal-Drouard L, Duchêne AM. A genome-scale analysis of mRNAs targeting to plant mitochondria: upstream AUGs in 5' untranslated regions reduce mitochondrial association. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 92:1132-1142. [PMID: 29044717 DOI: 10.1111/tpj.13749] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/26/2017] [Accepted: 09/29/2017] [Indexed: 06/07/2023]
Abstract
Intracellular sorting of mRNAs is an essential process for regulating gene expression and protein localization. Most mitochondrial proteins are nuclear-encoded and imported into the mitochondria through post-translational or co-translational processes. In the latter case, mRNAs are found to be enriched in the vicinity of mitochondria. A genome-scale analysis of mRNAs associated with mitochondria has been performed to determine plant cytosolic mRNAs targeted to the mitochondrial surface. Many messengers encoding mitochondrial proteins were found associated with mitochondria. These mRNAs correspond to particular functions and complexes, such as respiration or mitoribosomes, which indicates a coordinated control of mRNA localization within metabolic pathways. In addition, upstream AUGs in 5' untranslated regions (UTRs), which modulate the translation efficiency of downstream sequences, were found to negatively affect the association of mRNAs with mitochondria. A mutational approach coupled with in vivo mRNA visualization confirmed this observation. Moreover, this technique allowed the identification of 3'-UTRs as another essential element for mRNA localization at the mitochondrial surface. Therefore, this work offers new insights into the mechanism, function and regulation of the association of cytosolic mRNAs with plant mitochondria.
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Affiliation(s)
- Timothée Vincent
- 'Bioimage and Bioinformatics' Platform, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Audrey Vingadassalon
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Elodie Ubrig
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Kevin Azeredo
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Ola Srour
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Valérie Cognat
- 'Bioimage and Bioinformatics' Platform, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Stéfanie Graindorge
- 'Bioimage and Bioinformatics' Platform, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Thalia Salinas
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Laurence Maréchal-Drouard
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
| | - Anne-Marie Duchêne
- 'Metabolism and Trafficking of RNA Within the Plant Cell' Team, Institut de Biologie Moléculaire des Plantes, UPR 2357 du CNRS, Université de Strasbourg, 12 Rue du Général Zimmer, Strasbourg Cedex, 67084, France
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25
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Misgeld T, Schwarz TL. Mitostasis in Neurons: Maintaining Mitochondria in an Extended Cellular Architecture. Neuron 2017; 96:651-666. [PMID: 29096078 DOI: 10.1016/j.neuron.2017.09.055] [Citation(s) in RCA: 309] [Impact Index Per Article: 44.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 09/25/2017] [Accepted: 09/28/2017] [Indexed: 02/06/2023]
Abstract
Neurons have more extended and complex shapes than other cells and consequently face a greater challenge in distributing and maintaining mitochondria throughout their arbors. Neurons can last a lifetime, but proteins turn over rapidly. Mitochondria, therefore, need constant rejuvenation no matter how far they are from the soma. Axonal transport of mitochondria and mitochondrial fission and fusion contribute to this rejuvenation, but local protein synthesis is also likely. Maintenance of a healthy mitochondrial population also requires the clearance of damaged proteins and organelles. This involves degradation of individual proteins, sequestration in mitochondria-derived vesicles, organelle degradation by mitophagy and macroautophagy, and in some cases transfer to glial cells. Both long-range transport and local processing are thus at work in achieving neuronal mitostasis-the maintenance of an appropriately distributed pool of healthy mitochondria for the duration of a neuron's life. Accordingly, defects in the processes that support mitostasis are significant contributors to neurodegenerative disorders.
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Affiliation(s)
- Thomas Misgeld
- Technical University of Munich, Institute of Neuronal Cell Biology, Munich, Germany; German Center for Neurodegenerative Diseases, Munich, Germany; Munich Cluster for Systems Neurology, Munich, Germany; Center of Integrated Protein Science, Munich, Germany.
| | - Thomas L Schwarz
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA; F.M. Kirby Neurobiology Center, Children's Hospital, Boston, MA, USA.
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26
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Smith GM, Gallo G. The role of mitochondria in axon development and regeneration. Dev Neurobiol 2017; 78:221-237. [PMID: 29030922 DOI: 10.1002/dneu.22546] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 09/12/2017] [Accepted: 10/08/2017] [Indexed: 12/26/2022]
Abstract
Mitochondria are dynamic organelles that undergo transport, fission, and fusion. The three main functions of mitochondria are to generate ATP, buffer cytosolic calcium, and generate reactive oxygen species. A large body of evidence indicates that mitochondria are either primary targets for neurological disease states and nervous system injury, or are major contributors to the ensuing pathologies. However, the roles of mitochondria in the development and regeneration of axons have just begun to be elucidated. Advances in the understanding of the functional roles of mitochondria in neurons had been largely impeded by insufficient knowledge regarding the molecular mechanisms that regulate mitochondrial transport, stalling, fission/fusion, and a paucity of approaches to image and analyze mitochondria in living axons at the level of the single mitochondrion. However, technical advances in the imaging and analysis of mitochondria in living neurons and significant insights into the mechanisms that regulate mitochondrial dynamics have allowed the field to advance. Mitochondria have now been attributed important roles in the mechanism of axon extension, regeneration, and axon branching. The availability of new experimental tools is expected to rapidly increase our understanding of the functions of axonal mitochondria during both development and later regenerative attempts. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 221-237, 2018.
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Affiliation(s)
- George M Smith
- Department of Neuroscience, Temple University, Lewis Katz School of Medicine, Philadelphia, Pennsylvania, 19140.,Shriners Hospitals Pediatric Research Center, Temple University, Lewis Katz School of Medicine, Philadelphia, Pennsylvania, 19140
| | - Gianluca Gallo
- Department of Anatomy and Cell Biology, Temple University, Lewis Katz School of Medicine, Philadelphia, Pennsylvania, 19140.,Shriners Hospitals Pediatric Research Center, Temple University, Lewis Katz School of Medicine, Philadelphia, Pennsylvania, 19140
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Gale JR, Aschrafi A, Gioio AE, Kaplan BB. Nuclear-Encoded Mitochondrial mRNAs: A Powerful Force in Axonal Growth and Development. Neuroscientist 2017; 24:142-155. [PMID: 28614981 DOI: 10.1177/1073858417714225] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Axons, their growth cones, and synaptic nerve terminals are neuronal subcompartments that have high energetic needs. As such, they are enriched in mitochondria, which supply the ATP necessary to meet these demands. To date, a heterogeneous population of nuclear-encoded mitochondrial mRNAs has been identified in distal axons and growth cones. Accumulating evidence suggests that the local translation of these mRNAs is required for mitochondrial maintenance and axonal viability. Here, we review evidence that suggests a critical role for axonal translation of nuclear-encoded mitochondrial mRNAs in axonal growth and development. Additionally, we explore the role that site-specific translation at the mitochondria itself may play in this process. Finally, we briefly review the clinical implications of dysregulation of local translation of mitochondrial-related mRNAs in neurodevelopmental disorders.
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Affiliation(s)
- Jenna R Gale
- 1 Laboratory of Molecular Biology, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Armaz Aschrafi
- 1 Laboratory of Molecular Biology, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Anthony E Gioio
- 1 Laboratory of Molecular Biology, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Barry B Kaplan
- 1 Laboratory of Molecular Biology, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
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