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Salehi S, Zare A, Gandhi G, Sendtner M, Briese M. Ptbp2 re-expression rescues axon growth defects in Smn-deficient motoneurons. Front Mol Neurosci 2024; 17:1393779. [PMID: 39246602 PMCID: PMC11377325 DOI: 10.3389/fnmol.2024.1393779] [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: 02/29/2024] [Accepted: 08/08/2024] [Indexed: 09/10/2024] Open
Abstract
Spinal muscular atrophy (SMA) is a neuromuscular disorder caused by mutations or deletions in the survival motoneuron 1 (SMN1) gene, resulting in deficiency of the SMN protein that is essential for motoneuron function. Smn depletion in mice disturbs axonal RNA transport and translation, thereby contributing to axon growth impairment, muscle denervation, and motoneuron degeneration. However, the mechanisms whereby Smn loss causes axonal defects remain unclear. RNA localization and translation in axons are controlled by RNA-binding proteins (RBP) and we recently observed that the neuronal RBP Ptbp2 modulates axon growth in motoneurons. Here, we identify Smn as an interactor of Ptbp2 in the cytosolic compartments of motoneurons. We show that the expression level of Ptbp2 is reduced in axons but not in the somata of Smn-depleted motoneurons. This is accompanied by reduced synthesis of the RBP hnRNP R in axons. Re-expression of Ptbp2 in axons compensates for the deficiency of Smn and rescues the defects in axon elongation and growth cone maturation observed in Smn-deficient motoneurons. Our data suggest that Ptbp2 and Smn are components of cytosolic mRNP particles, contributing to the precise spatial and temporal control of protein synthesis within axons and axon terminals.
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Affiliation(s)
- Saeede Salehi
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Abdolhossein Zare
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Gayatri Gandhi
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Michael Briese
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
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2
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Chekulaeva M. Mechanistic insights into the basis of widespread RNA localization. Nat Cell Biol 2024; 26:1037-1046. [PMID: 38956277 DOI: 10.1038/s41556-024-01444-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 05/20/2024] [Indexed: 07/04/2024]
Abstract
The importance of subcellular mRNA localization is well established, but the underlying mechanisms mostly remain an enigma. Early studies suggested that specific mRNA sequences recruit RNA-binding proteins (RBPs) to regulate mRNA localization. However, despite the observation of thousands of localized mRNAs, only a handful of these sequences and RBPs have been identified. This suggests the existence of alternative, and possibly predominant, mechanisms for mRNA localization. Here I re-examine currently described mRNA localization mechanisms and explore alternative models that could account for its widespread occurrence.
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Affiliation(s)
- Marina Chekulaeva
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany.
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3
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Sharma G, Paganin M, Lauria F, Perenthaler E, Viero G. The SMN-ribosome interplay: a new opportunity for Spinal Muscular Atrophy therapies. Biochem Soc Trans 2024; 52:465-479. [PMID: 38391004 PMCID: PMC10903476 DOI: 10.1042/bst20231116] [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: 12/22/2023] [Revised: 02/12/2024] [Accepted: 02/13/2024] [Indexed: 02/24/2024]
Abstract
The underlying cause of Spinal Muscular Atrophy (SMA) is in the reduction of survival motor neuron (SMN) protein levels due to mutations in the SMN1 gene. The specific effects of SMN protein loss and the resulting pathological alterations are not fully understood. Given the crucial roles of the SMN protein in snRNP biogenesis and its interactions with ribosomes and translation-related proteins and mRNAs, a decrease in SMN levels below a specific threshold in SMA is expected to affect translational control of gene expression. This review covers both direct and indirect SMN interactions across various translation-related cellular compartments and processes, spanning from ribosome biogenesis to local translation and beyond. Additionally, it aims to outline deficiencies and alterations in translation observed in SMA models and patients, while also discussing the implications of the relationship between SMN protein and the translation machinery within the context of current and future therapies.
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4
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Cottam NC, Bamfo T, Harrington MA, Charvet CJ, Hekmatyar K, Tulin N, Sun J. Cerebellar structural, astrocytic, and neuronal abnormalities in the SMNΔ7 mouse model of spinal muscular atrophy. Brain Pathol 2023; 33:e13162. [PMID: 37218083 PMCID: PMC10467044 DOI: 10.1111/bpa.13162] [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: 11/18/2022] [Accepted: 04/18/2023] [Indexed: 05/24/2023] Open
Abstract
Spinalmuscular atrophy (SMA) is a neuromuscular disease that affects as many as 1 in 6000 individuals at birth, making it the leading genetic cause of infant mortality. A growing number of studies indicate that SMA is a multi-system disease. The cerebellum has received little attention even though it plays an important role in motor function and widespread pathology has been reported in the cerebella of SMA patients. In this study, we assessed SMA pathology in the cerebellum using structural and diffusion magnetic resonance imaging, immunohistochemistry, and electrophysiology with the SMNΔ7 mouse model. We found a significant disproportionate loss in cerebellar volume, decrease in afferent cerebellar tracts, selective lobule-specific degeneration of Purkinje cells, abnormal lobule foliation and astrocyte integrity, and a decrease in spontaneous firing of cerebellar output neurons in the SMA mice compared to controls. Our data suggest that defects in cerebellar structure and function due to decreased survival motor neuron (SMN) levels impair the functional cerebellar output affecting motor control, and that cerebellar pathology should be addressed to achieve comprehensive treatment and therapy for SMA patients.
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Affiliation(s)
- Nicholas C. Cottam
- Department of Biological SciencesDelaware State UniversityDoverDelawareUSA
| | - Tiffany Bamfo
- Department of Biological SciencesDelaware State UniversityDoverDelawareUSA
| | | | - Christine J. Charvet
- Delaware Center for Neuroscience ResearchDelaware State UniversityDoverDelawareUSA
- Department of Anatomy, Physiology and PharmacologyAuburn UniversityAuburnAlabamaUSA
- Department of PsychologyDelaware State UniversityDoverDEUnited States
| | - Khan Hekmatyar
- Center for Biomedical and Brain ImagingUniversity of DelawareNewarkDelawareUSA
- Bioimaging Research Center for Biomedical and Brain ImagingUniversity of GeorgiaAthensGeorgiaUSA
| | - Nikita Tulin
- Department of NeuroscienceTemple UniversityPhiladelphiaPennsylvaniaUSA
| | - Jianli Sun
- Department of Biological SciencesDelaware State UniversityDoverDelawareUSA
- Delaware Center for Neuroscience ResearchDelaware State UniversityDoverDelawareUSA
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5
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Wang S, Sun S. Translation dysregulation in neurodegenerative diseases: a focus on ALS. Mol Neurodegener 2023; 18:58. [PMID: 37626421 PMCID: PMC10464328 DOI: 10.1186/s13024-023-00642-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023] Open
Abstract
RNA translation is tightly controlled in eukaryotic cells to regulate gene expression and maintain proteome homeostasis. RNA binding proteins, translation factors, and cell signaling pathways all modulate the translation process. Defective translation is involved in multiple neurological diseases including amyotrophic lateral sclerosis (ALS). ALS is a progressive neurodegenerative disorder and poses a major public health challenge worldwide. Over the past few years, tremendous advances have been made in the understanding of the genetics and pathogenesis of ALS. Dysfunction of RNA metabolisms, including RNA translation, has been closely associated with ALS. Here, we first introduce the general mechanisms of translational regulation under physiological and stress conditions and review well-known examples of translation defects in neurodegenerative diseases. We then focus on ALS-linked genes and discuss the recent progress on how translation is affected by various mutant genes and the repeat expansion-mediated non-canonical translation in ALS.
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Affiliation(s)
- Shaopeng Wang
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Shuying Sun
- Department of Physiology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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6
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Yang Z, Yu J, Zhang J, Song H, Ye H, Liu J, Wang N, Che P, Long G, Wang Y, Park J, Ji SJ. Facilitation of axonal transcriptome analysis with quantitative microfluidic devices. LAB ON A CHIP 2023; 23:2217-2227. [PMID: 37067243 DOI: 10.1039/d2lc01183b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Microfluidic chambers are powerful tools for studying axonal mRNA localization and translation in neurons. In addition to specific manipulation and measurements of axons, microfluidic chambers are used for collecting axonal materials to perform axonal transcriptome analysis. However, traditional bipartite and tripartite chambers have limitations either in purity or quantity of collected axons. Here, we improved the design of traditional chambers. Moreover, we developed two new quantitative chambers, multi-compartmental quantitative bipartite chamber (MQBC) and long quantitative tripartite chamber (LQTC). Compared with the traditional chambers, MQBC and LQTC could dramatically increase the efficiency in collecting axonal RNA. Finally, we applied these chambers to do comparative axon transcriptome analysis of different types of neurons. Thus, our newly designed quantitative chambers significantly improve axon collection efficiency and facilitate axonal transcriptome analysis.
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Affiliation(s)
- Zhuoxuan Yang
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Jun Yu
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Jian Zhang
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Huixue Song
- School of Microelectronics, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
| | - Haixia Ye
- School of Microelectronics, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
| | - Jianhui Liu
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Nijia Wang
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Pengfei Che
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Gaoxin Long
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Yunxuan Wang
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Jaewon Park
- School of Microelectronics, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
- OJeong Resilience Institute (OJERI), Korea University, Seoul, 02841, Korea.
| | - Sheng-Jian Ji
- School of Life Sciences, Department of Neuroscience, Brain Research Center, Shenzhen Key Laboratory of Gene Regulation and Systems Biology, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
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7
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Piol D, Robberechts T, Da Cruz S. Lost in local translation: TDP-43 and FUS in axonal/neuromuscular junction maintenance and dysregulation in amyotrophic lateral sclerosis. Neuron 2023; 111:1355-1380. [PMID: 36963381 DOI: 10.1016/j.neuron.2023.02.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/21/2022] [Accepted: 02/16/2023] [Indexed: 03/26/2023]
Abstract
Key early features of amyotrophic lateral sclerosis (ALS) are denervation of neuromuscular junctions and axonal degeneration. Motor neuron homeostasis relies on local translation through controlled regulation of axonal mRNA localization, transport, and stability. Yet the composition of the local transcriptome, translatome (mRNAs locally translated), and proteome during health and disease remains largely unexplored. This review covers recent discoveries on axonal translation as a critical mechanism for neuronal maintenance/survival. We focus on two RNA binding proteins, transactive response DNA binding protein-43 (TDP-43) and fused in sarcoma (FUS), whose mutations cause ALS and frontotemporal dementia (FTD). Emerging evidence points to their essential role in the maintenance of axons and synapses, including mRNA localization, transport, and local translation, and whose dysfunction may contribute to ALS. Finally, we describe recent advances in omics-based approaches mapping compartment-specific local RNA and protein compositions, which will be invaluable to elucidate fundamental local processes and identify key targets for therapy development.
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Affiliation(s)
- Diana Piol
- VIB-KU Leuven Center for Brain and Disease Research, Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Belgium
| | - Tessa Robberechts
- VIB-KU Leuven Center for Brain and Disease Research, Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Belgium
| | - Sandrine Da Cruz
- VIB-KU Leuven Center for Brain and Disease Research, Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Belgium.
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8
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Hennlein L, Ghanawi H, Gerstner F, Palominos García E, Yildirim E, Saal-Bauernschubert L, Moradi M, Deng C, Klein T, Appenzeller S, Sauer M, Briese M, Simon C, Sendtner M, Jablonka S. Plastin 3 rescues cell surface translocation and activation of TrkB in spinal muscular atrophy. J Cell Biol 2023; 222:e202204113. [PMID: 36607273 PMCID: PMC9827530 DOI: 10.1083/jcb.202204113] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 10/12/2022] [Accepted: 12/08/2022] [Indexed: 01/07/2023] Open
Abstract
Plastin 3 (PLS3) is an F-actin-bundling protein that has gained attention as a modifier of spinal muscular atrophy (SMA) pathology. SMA is a lethal pediatric neuromuscular disease caused by loss of or mutations in the Survival Motor Neuron 1 (SMN1) gene. Pathophysiological hallmarks are cellular maturation defects of motoneurons prior to degeneration. Despite the observed beneficial modifying effect of PLS3, the mechanism of how it supports F-actin-mediated cellular processes in motoneurons is not yet well understood. Our data reveal disturbed F-actin-dependent translocation of the Tropomyosin receptor kinase B (TrkB) to the cell surface of Smn-deficient motor axon terminals, resulting in reduced TrkB activation by its ligand brain-derived neurotrophic factor (BDNF). Improved actin dynamics by overexpression of hPLS3 restores membrane recruitment and activation of TrkB and enhances spontaneous calcium transients by increasing Cav2.1/2 "cluster-like" formations in SMA axon terminals. Thus, our study provides a novel role for PLS3 in supporting correct alignment of transmembrane proteins, a key mechanism for (moto)-neuronal development.
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Affiliation(s)
- Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Hanaa Ghanawi
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Florian Gerstner
- Carl-Ludwig-Institute for Physiology, Leipzig University, Leipzig, Germany
| | | | - Ezgi Yildirim
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | | | - Mehri Moradi
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Chunchu Deng
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Teresa Klein
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Silke Appenzeller
- Comprehensive Cancer Center Mainfranken; Core Unit Bioinformatics, University Hospital Würzburg, Würzburg, Germany
| | - Markus Sauer
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Michael Briese
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Christian Simon
- Carl-Ludwig-Institute for Physiology, Leipzig University, Leipzig, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
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9
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Pinho-Correia LM, Prokop A. Maintaining essential microtubule bundles in meter-long axons: a role for local tubulin biogenesis? Brain Res Bull 2023; 193:131-145. [PMID: 36535305 DOI: 10.1016/j.brainresbull.2022.12.005] [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: 10/16/2022] [Revised: 12/12/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
Axons are the narrow, up-to-meter long cellular processes of neurons that form the biological cables wiring our nervous system. Most axons must survive for an organism's lifetime, i.e. up to a century in humans. Axonal maintenance depends on loose bundles of microtubules that run without interruption all along axons. The continued turn-over and the extension of microtubule bundles during developmental, regenerative or plastic growth requires the availability of α/β-tubulin heterodimers up to a meter away from the cell body. The underlying regulation in axons is poorly understood and hardly features in past and contemporary research. Here we discuss potential mechanisms, particularly focussing on the possibility of local tubulin biogenesis in axons. Current knowledge might suggest that local translation of tubulin takes place in axons, but far less is known about the post-translational machinery of tubulin biogenesis involving three chaperone complexes: prefoldin, CCT and TBC. We discuss functional understanding of these chaperones from a range of model organisms including yeast, plants, flies and mice, and explain what is known from human diseases. Microtubules across species depend on these chaperones, and they are clearly required in the nervous system. However, most chaperones display a high degree of functional pleiotropy, partly through independent functions of individual subunits outside their complexes, thus posing a challenge to experimental studies. Notably, we found hardly any studies that investigate their presence and function particularly in axons, thus highlighting an important gap in our understanding of axon biology and pathology.
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Affiliation(s)
- Liliana Maria Pinho-Correia
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biology, Manchester, UK
| | - Andreas Prokop
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biology, Manchester, UK.
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10
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Miralles MP, Sansa A, Beltran M, Soler RM, Garcera A. Survival motor neuron protein and neurite degeneration are regulated by Gemin3 in spinal muscular atrophy motoneurons. Front Cell Neurosci 2022; 16:1054270. [PMID: 36619669 PMCID: PMC9813745 DOI: 10.3389/fncel.2022.1054270] [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: 09/26/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022] Open
Abstract
Spinal Muscular Atrophy (SMA) is a genetic neuromuscular disorder caused by reduction of the ubiquitously expressed protein Survival Motor Neuron (SMN). Low levels of SMN impact on spinal cord motoneurons (MNs) causing their degeneration and progressive muscle weakness and atrophy. To study the molecular mechanisms leading to cell loss in SMN-reduced MNs, we analyzed the NF-κB intracellular pathway in SMA models. NF-κB pathway activation is required for survival and regulates SMN levels in cultured MNs. Here we describe that NF-κB members, inhibitor of kappa B kinase beta (IKKβ), and RelA, were reduced in SMA mouse and human MNs. In addition, we observed that Gemin3 protein level was decreased in SMA MNs, but not in non-neuronal SMA cells. Gemin3 is a core member of the SMN complex responsible for small nuclear ribonucleoprotein biogenesis, and it regulates NF-κB activation through the mitogen-activated protein kinase TAK1. Our experiments showed that Gemin3 knockdown reduced SMN, IKKβ, and RelA protein levels, and caused significant neurite degeneration. Overexpression of SMN increased Gemin3 protein in SMA MNs, but did not prevent neurite degeneration in Gemin3 knockdown cells. These data indicated that Gemin3 reduction may contribute to cell degeneration in SMA MNs.
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11
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Zilio E, Piano V, Wirth B. Mitochondrial Dysfunction in Spinal Muscular Atrophy. Int J Mol Sci 2022; 23:10878. [PMID: 36142791 PMCID: PMC9503857 DOI: 10.3390/ijms231810878] [Citation(s) in RCA: 10] [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: 08/30/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a devastating neuromuscular disorder caused by recessive mutations in the SMN1 gene, globally affecting ~8-14 newborns per 100,000. The severity of the disease depends on the residual levels of functional survival of motor neuron protein, SMN. SMN is a ubiquitously expressed RNA binding protein involved in a plethora of cellular processes. In this review, we discuss the effects of SMN loss on mitochondrial functions in the neuronal and muscular systems that are the most affected in patients with spinal muscular atrophy. Our aim is to highlight how mitochondrial defects may contribute to disease progression and how restoring mitochondrial functionality may be a promising approach to develop new therapies. We also collected from previous studies a list of transcripts encoding mitochondrial proteins affected in various SMA models. Moreover, we speculate that in adulthood, when motor neurons require only very low SMN levels, the natural deterioration of mitochondria associated with aging may be a crucial triggering factor for adult spinal muscular atrophy, and this requires particular attention for therapeutic strategies.
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Affiliation(s)
- Eleonora Zilio
- Institute of Human Genetics, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany
| | - Valentina Piano
- Institute of Human Genetics, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
- Institute for Genetics, University of Cologne, 50674 Cologne, Germany
- Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany
| | - Brunhilde Wirth
- Institute of Human Genetics, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
- Institute for Genetics, University of Cologne, 50674 Cologne, Germany
- Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany
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12
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Deng C, Reinhard S, Hennlein L, Eilts J, Sachs S, Doose S, Jablonka S, Sauer M, Moradi M, Sendtner M. Impaired dynamic interaction of axonal endoplasmic reticulum and ribosomes contributes to defective stimulus-response in spinal muscular atrophy. Transl Neurodegener 2022; 11:31. [PMID: 35650592 PMCID: PMC9161492 DOI: 10.1186/s40035-022-00304-2] [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: 10/15/2021] [Accepted: 04/28/2022] [Indexed: 11/19/2022] Open
Abstract
Background Axonal degeneration and defects in neuromuscular neurotransmission represent a pathological hallmark in spinal muscular atrophy (SMA) and other forms of motoneuron disease. These pathological changes do not only base on altered axonal and presynaptic architecture, but also on alterations in dynamic movements of organelles and subcellular structures that are not necessarily reflected by static histopathological changes. The dynamic interplay between the axonal endoplasmic reticulum (ER) and ribosomes is essential for stimulus-induced local translation in motor axons and presynaptic terminals. However, it remains enigmatic whether the ER and ribosome crosstalk is impaired in the presynaptic compartment of motoneurons with Smn (survival of motor neuron) deficiency that could contribute to axonopathy and presynaptic dysfunction in SMA. Methods Using super-resolution microscopy, proximity ligation assay (PLA) and live imaging of cultured motoneurons from a mouse model of SMA, we investigated the dynamics of the axonal ER and ribosome distribution and activation. Results We observed that the dynamic remodeling of ER was impaired in axon terminals of Smn-deficient motoneurons. In addition, in axon terminals of Smn-deficient motoneurons, ribosomes failed to respond to the brain-derived neurotrophic factor stimulation, and did not undergo rapid association with the axonal ER in response to extracellular stimuli. Conclusions These findings implicate impaired dynamic interplay between the ribosomes and ER in axon terminals of motoneurons as a contributor to the pathophysiology of SMA and possibly also other motoneuron diseases. Supplementary Information The online version contains supplementary material available at 10.1186/s40035-022-00304-2.
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Affiliation(s)
- Chunchu Deng
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, 97078, Würzburg, Germany
| | - Sebastian Reinhard
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Wuerzburg, 97074, Würzburg, Germany
| | - Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, 97078, Würzburg, Germany
| | - Janna Eilts
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Wuerzburg, 97074, Würzburg, Germany
| | - Stefan Sachs
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Wuerzburg, 97074, Würzburg, Germany
| | - Sören Doose
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Wuerzburg, 97074, Würzburg, Germany
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, 97078, Würzburg, Germany
| | - Markus Sauer
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Wuerzburg, 97074, Würzburg, Germany
| | - Mehri Moradi
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, 97078, Würzburg, Germany.
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, 97078, Würzburg, Germany.
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13
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Taliaferro JM. Transcriptome-scale methods for uncovering subcellular RNA localization mechanisms. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119202. [PMID: 34998919 PMCID: PMC9035289 DOI: 10.1016/j.bbamcr.2021.119202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 12/03/2021] [Accepted: 12/17/2021] [Indexed: 12/21/2022]
Abstract
Across a variety of systems, thousands of RNAs are localized to specific subcellular locations. However, for the vast majority of these RNAs, the mechanisms that underlie their transport are unknown. Historically, these mechanisms were uncovered for a single transcript at a time by laboriously testing the ability of RNA fragments to direct transcript localization. Recently developed methods profile the content of subcellular transcriptomes using high-throughput sequencing, allowing the analysis of the localization of thousands of transcripts at once. By identifying commonalities shared among multiple localized transcripts, these methods have the potential to rapidly expand our understanding of RNA localization mechanisms.
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Affiliation(s)
- J Matthew Taliaferro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA; RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
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14
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Jablonka S, Hennlein L, Sendtner M. Therapy development for spinal muscular atrophy: perspectives for muscular dystrophies and neurodegenerative disorders. Neurol Res Pract 2022; 4:2. [PMID: 34983696 PMCID: PMC8725368 DOI: 10.1186/s42466-021-00162-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/21/2021] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Major efforts have been made in the last decade to develop and improve therapies for proximal spinal muscular atrophy (SMA). The introduction of Nusinersen/Spinraza™ as an antisense oligonucleotide therapy, Onasemnogene abeparvovec/Zolgensma™ as an AAV9-based gene therapy and Risdiplam/Evrysdi™ as a small molecule modifier of pre-mRNA splicing have set new standards for interference with neurodegeneration. MAIN BODY Therapies for SMA are designed to interfere with the cellular basis of the disease by modifying pre-mRNA splicing and enhancing expression of the Survival Motor Neuron (SMN) protein, which is only expressed at low levels in this disorder. The corresponding strategies also can be applied to other disease mechanisms caused by loss of function or toxic gain of function mutations. The development of therapies for SMA was based on the use of cell culture systems and mouse models, as well as innovative clinical trials that included readouts that had originally been introduced and optimized in preclinical studies. This is summarized in the first part of this review. The second part discusses current developments and perspectives for amyotrophic lateral sclerosis, muscular dystrophies, Parkinson's and Alzheimer's disease, as well as the obstacles that need to be overcome to introduce RNA-based therapies and gene therapies for these disorders. CONCLUSION RNA-based therapies offer chances for therapy development of complex neurodegenerative disorders such as amyotrophic lateral sclerosis, muscular dystrophies, Parkinson's and Alzheimer's disease. The experiences made with these new drugs for SMA, and also the experiences in AAV gene therapies could help to broaden the spectrum of current approaches to interfere with pathophysiological mechanisms in neurodegeneration.
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Affiliation(s)
- Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Versbacher Str. 5, 97078, Wuerzburg, Germany.
| | - Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Versbacher Str. 5, 97078, Wuerzburg, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Versbacher Str. 5, 97078, Wuerzburg, Germany.
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15
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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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16
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Deng C, Moradi M, Reinhard S, Ji C, Jablonka S, Hennlein L, Lüningschrör P, Doose S, Sauer M, Sendtner M. Dynamic remodeling of ribosomes and endoplasmic reticulum in axon terminals of motoneurons. J Cell Sci 2021; 134:272552. [PMID: 34668554 DOI: 10.1242/jcs.258785] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 10/14/2021] [Indexed: 12/23/2022] Open
Abstract
In neurons, the endoplasmic reticulum (ER) forms a highly dynamic network that enters axons and presynaptic terminals and plays a central role in Ca2+ homeostasis and synapse maintenance; however, the underlying mechanisms involved in regulation of its dynamic remodeling as well as its function in axon development and presynaptic differentiation remain elusive. Here, we used high-resolution microscopy and live-cell imaging to investigate rapid movements of the ER and ribosomes in axons of cultured motoneurons after stimulation with brain-derived neurotrophic factor. Our results indicate that the ER extends into axonal growth cone filopodia, where its integrity and dynamic remodeling are regulated mainly by actin and the actin-based motor protein myosin VI (encoded by Myo6). Additionally, we found that in axonal growth cones, ribosomes assemble into 80S subunits within seconds and associate with the ER in response to extracellular stimuli, which describes a novel function of axonal ER in dynamic regulation of local translation. This article has an associated First Person interview with Chunchu Deng, joint first author of the paper.
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Affiliation(s)
- Chunchu Deng
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Mehri Moradi
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Sebastian Reinhard
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, 97074 Würzburg, Germany
| | - Changhe Ji
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Patrick Lüningschrör
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Sören Doose
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, 97074 Würzburg, Germany
| | - Markus Sauer
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, 97074 Würzburg, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
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17
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Kariyawasam DST, D'Silva AM, Herbert K, Howells J, Carey K, Kandula T, Farrar MA, Lin CSY. Axonal excitability changes in children with spinal muscular atrophy treated with nusinersen. J Physiol 2021; 600:95-109. [PMID: 34783018 DOI: 10.1113/jp282249] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/05/2021] [Indexed: 11/08/2022] Open
Abstract
Spinal muscular atrophy (SMA) is associated with developmental disruption of motor axons in ventral roots of the spinal cord alongside motor axon degeneration. The pathogenesis of peripheral axonal change during development is pertinent to understand treatment response. Nerve excitability techniques, stimulating the median motor nerve at the wrist, were utilised to investigate axonal change during neurodevelopment in 24 children with SMA, compared with 71 age-matched controls. Longitudinal axonal response to nusinersen treatment in 18 children was also investigated. Significant differences in axonal development were noted in the youngest children with SMA, signified by reduced compound muscle action potential (CMAP) (P = 0.030), higher axonal threshold (P = 0.016), rheobase (minimal current amplitude of infinite duration, required to generate an action potential) (P = 0.012) and greater changes in depolarising and hyperpolarising threshold electrotonus. Subexcitability increased in all children with SMA, compared to controls. With treatment, nerve excitability changes were observed prominently in young children, with increases in CMAP, reduction in axonal threshold, fanning-in of threshold electrotonus, increase in resting current-threshold slope and reduction in subexcitability. Whilst motor axons continue to mature in SMA, developmental delays in passive and active membrane properties occur especially in early childhood. Concurrently, motor axons actively undergo degeneration. Nusinersen restores the developmental trajectory of motor axons reducing degeneration, especially in children with early treatment initiation. Our findings move the field forward in understanding the developmental aspect of childhood-onset motor neurone diseases and changes in axonal function associated with disease modification. KEY POINTS: Pathomechanisms in spinal muscular atrophy involve concurrent neurodevelopmental and neurodegenerative processes. The greatest delays in maturation of the passive and active properties of the peripheral motor axon are seen in early childhood. Nusinersen facilitates developmental recovery of the motor axon whilst also reducing neurodegeneration. Axonal dysfunction is reversed with SMN repletion particularly when intervention occurs early in development.
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Affiliation(s)
- Didu S T Kariyawasam
- Department of Neurology, Randwick, Sydney Children's Hospital, Sydney, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Arlene M D'Silva
- School of Women's and Children's Health, University of New South Wales Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Karen Herbert
- Department of Physiotherapy, Randwick, Sydney Children's Hospital, Sydney, New South Wales, Australia
| | - James Howells
- Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Kate Carey
- School of Women's and Children's Health, University of New South Wales Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Tejaswi Kandula
- Department of Neurology, Randwick, Sydney Children's Hospital, Sydney, New South Wales, Australia
| | - Michelle A Farrar
- Department of Neurology, Randwick, Sydney Children's Hospital, Sydney, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Cindy Shin-Yi Lin
- Translational Research Collective, Faculty of Medicine and Health, Brain and Mind Centre, University of Sydney, Sydney, New South Wales, Australia
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18
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Fusco CM, Desch K, Dörrbaum AR, Wang M, Staab A, Chan ICW, Vail E, Villeri V, Langer JD, Schuman EM. Neuronal ribosomes exhibit dynamic and context-dependent exchange of ribosomal proteins. Nat Commun 2021; 12:6127. [PMID: 34675203 PMCID: PMC8531293 DOI: 10.1038/s41467-021-26365-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 09/29/2021] [Indexed: 12/11/2022] Open
Abstract
Owing to their morphological complexity and dense network connections, neurons modify their proteomes locally, using mRNAs and ribosomes present in the neuropil (tissue enriched for dendrites and axons). Although ribosome biogenesis largely takes place in the nucleus and perinuclear region, neuronal ribosomal protein (RP) mRNAs have been frequently detected remotely, in dendrites and axons. Here, using imaging and ribosome profiling, we directly detected the RP mRNAs and their translation in the neuropil. Combining brief metabolic labeling with mass spectrometry, we found that a group of RPs rapidly associated with translating ribosomes in the cytoplasm and that this incorporation was independent of canonical ribosome biogenesis. Moreover, the incorporation probability of some RPs was regulated by location (neurites vs. cell bodies) and changes in the cellular environment (following oxidative stress). Our results suggest new mechanisms for the local activation, repair and/or specialization of the translational machinery within neuronal processes, potentially allowing neuronal synapses a rapid means to regulate local protein synthesis.
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Affiliation(s)
- Claudia M. Fusco
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Kristina Desch
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Aline R. Dörrbaum
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany ,Present Address: MOS, Center for Mass Spectrometry and Optical Spectroscopy, Mannheim, Germany
| | - Mantian Wang
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany ,grid.508836.0Present Address: Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Anja Staab
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Ivy C. W. Chan
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany ,grid.424247.30000 0004 0438 0426Present Address: German Center for Neurodegenerative Diseases, Bonn, Germany
| | - Eleanor Vail
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Veronica Villeri
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany ,grid.412041.20000 0001 2106 639XPresent Address: Department of Neuroscience, University of Bordeaux, Bordeaux, France
| | - Julian D. Langer
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany ,grid.419494.50000 0001 1018 9466Max Planck Institute for Biophysics, Frankfurt, Germany
| | - Erin M. Schuman
- grid.419505.c0000 0004 0491 3878Max Planck Institute for Brain Research, Frankfurt, Germany
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19
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Di Paolo A, Garat J, Eastman G, Farias J, Dajas-Bailador F, Smircich P, Sotelo-Silveira JR. Functional Genomics of Axons and Synapses to Understand Neurodegenerative Diseases. Front Cell Neurosci 2021; 15:686722. [PMID: 34248504 PMCID: PMC8267896 DOI: 10.3389/fncel.2021.686722] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 06/02/2021] [Indexed: 01/02/2023] Open
Abstract
Functional genomics studies through transcriptomics, translatomics and proteomics have become increasingly important tools to understand the molecular basis of biological systems in the last decade. In most cases, when these approaches are applied to the nervous system, they are centered in cell bodies or somatodendritic compartments, as these are easier to isolate and, at least in vitro, contain most of the mRNA and proteins present in all neuronal compartments. However, key functional processes and many neuronal disorders are initiated by changes occurring far away from cell bodies, particularly in axons (axopathologies) and synapses (synaptopathies). Both neuronal compartments contain specific RNAs and proteins, which are known to vary depending on their anatomical distribution, developmental stage and function, and thus form the complex network of molecular pathways required for neuron connectivity. Modifications in these components due to metabolic, environmental, and/or genetic issues could trigger or exacerbate a neuronal disease. For this reason, detailed profiling and functional understanding of the precise changes in these compartments may thus yield new insights into the still intractable molecular basis of most neuronal disorders. In the case of synaptic dysfunctions or synaptopathies, they contribute to dozens of diseases in the human brain including neurodevelopmental (i.e., autism, Down syndrome, and epilepsy) as well as neurodegenerative disorders (i.e., Alzheimer's and Parkinson's diseases). Histological, biochemical, cellular, and general molecular biology techniques have been key in understanding these pathologies. Now, the growing number of omics approaches can add significant extra information at a high and wide resolution level and, used effectively, can lead to novel and insightful interpretations of the biological processes at play. This review describes current approaches that use transcriptomics, translatomics and proteomic related methods to analyze the axon and presynaptic elements, focusing on the relationship that axon and synapses have with neurodegenerative diseases.
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Affiliation(s)
- Andres Di Paolo
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Joaquin Garat
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Guillermo Eastman
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Joaquina Farias
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Polo de Desarrollo Universitario “Espacio de Biología Vegetal del Noreste”, Centro Universitario Regional Noreste, Universidad de la República (UdelaR), Tacuarembó, Uruguay
| | - Federico Dajas-Bailador
- School of Life Sciences, Medical School Building, University of Nottingham, Nottingham, United Kingdom
| | - Pablo Smircich
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Universidad de la República (UdelaR), Montevideo, Uruguay
| | - José Roberto Sotelo-Silveira
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
- Departamento de Biología Celular y Molecular, Facultad de Ciencias, Universidad de la República (UdelaR), Montevideo, Uruguay
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20
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Di Paolo A, Farias J, Garat J, Macklin A, Ignatchenko V, Kislinger T, Sotelo Silveira J. Rat Sciatic Nerve Axoplasm Proteome Is Enriched with Ribosomal Proteins during Regeneration Processes. J Proteome Res 2021; 20:2506-2520. [PMID: 33793244 DOI: 10.1021/acs.jproteome.0c00980] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Axons are complex subcellular compartments that are extremely long in relation to cell bodies, especially in peripheral nerves. Many processes are required and regulated during axon injury, including anterograde and retrograde transport, glia-to-axon macromolecular transfer, and local axonal protein synthesis. Many in vitro omics approaches have been used to gain insight into these processes, but few have been applied in vivo. Here we adapted the osmotic ex vivo axoplasm isolation method and analyzed the adult rat sciatic-nerve-extruded axoplasm by label-free quantitative proteomics before and after injury. 2087 proteins groups were detected in the axoplasm, revealing translation machinery and microtubule-associated proteins as the most overrepresented biological processes. Ribosomal proteins (73) were detected in the uninjured axoplasm and increased their levels after injury but not within whole sciatic nerves. Meta-analysis showed that detected ribosomal proteins were present in in vitro axonal proteomes. Because local protein synthesis is important for protein localization, we were interested in detecting the most abundant newly synthesized axonal proteins in vivo. With an MS/MS-BONCAT approach, we detected 42 newly synthesized protein groups. Overall, our work indicates that proteomics profiling is useful for local axonal interrogation and suggests that ribosomal proteins may play an important role, especially during injury.
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Affiliation(s)
- Andres Di Paolo
- Departamento de Proteínas y Ácidos Nucleicos, IIBCE, 11600 Montevideo, Uruguay.,Departamento de Genómica, IIBCE, 11600 Montevideo, Uruguay
| | | | - Joaquin Garat
- Departamento de Genómica, IIBCE, 11600 Montevideo, Uruguay
| | - Andrew Macklin
- Princess Margaret Cancer Centre, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Vladimir Ignatchenko
- Princess Margaret Cancer Centre, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Thomas Kislinger
- Princess Margaret Cancer Centre, 101 College Street, Toronto, Ontario M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - José Sotelo Silveira
- Departamento de Genómica, IIBCE, 11600 Montevideo, Uruguay.,Departamento de Biología Celular y Molecular, Facultad de Ciencias, 11400 Montevideo, Uruguay
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21
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Ji C, Bader J, Ramanathan P, Hennlein L, Meissner F, Jablonka S, Mann M, Fischer U, Sendtner M, Briese M. Interaction of 7SK with the Smn complex modulates snRNP production. Nat Commun 2021; 12:1278. [PMID: 33627647 PMCID: PMC7904863 DOI: 10.1038/s41467-021-21529-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/29/2021] [Indexed: 11/09/2022] Open
Abstract
Gene expression requires tight coordination of the molecular machineries that mediate transcription and splicing. While the interplay between transcription kinetics and spliceosome fidelity has been investigated before, less is known about mechanisms regulating the assembly of the spliceosomal machinery in response to transcription changes. Here, we report an association of the Smn complex, which mediates spliceosomal snRNP biogenesis, with the 7SK complex involved in transcriptional regulation. We found that Smn interacts with the 7SK core components Larp7 and Mepce and specifically associates with 7SK subcomplexes containing hnRNP R. The association between Smn and 7SK complexes is enhanced upon transcriptional inhibition leading to reduced production of snRNPs. Taken together, our findings reveal a functional association of Smn and 7SK complexes that is governed by global changes in transcription. Thus, in addition to its canonical nuclear role in transcriptional regulation, 7SK has cytosolic functions in fine-tuning spliceosome production according to transcriptional demand. The noncoding RNA 7SK controls the transcription of mRNAs. Here, the authors show that the 7SK complex interacts with the Smn complex, suggesting crosstalk between transcription and snRNP assembly.
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Affiliation(s)
- Changhe Ji
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Jakob Bader
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Pradhipa Ramanathan
- Department of Biochemistry, Theodor Boveri Institute, University of Wuerzburg, Wuerzburg, Germany
| | - Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Felix Meissner
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany.,Experimental Systems Immunology, Max Planck Institute of Biochemistry, Martinsried, Germany.,Department for Systems Immunology & Proteomics, Institute of Innate Immunity, University Hospitals, University of Bonn, Bonn, Germany
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany.,NNF Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Utz Fischer
- Department of Biochemistry, Theodor Boveri Institute, University of Wuerzburg, Wuerzburg, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, Wuerzburg, Germany.
| | - Michael Briese
- Institute of Clinical Neurobiology, University Hospital Wuerzburg, Wuerzburg, Germany.
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22
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Mofatteh M. Neurodegeneration and axonal mRNA transportation. AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2021; 10:1-12. [PMID: 33815964 PMCID: PMC8012751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
The prevalence of neurodegenerative diseases is accelerating in rapidly aging global population. Novel and effective diagnostic and therapeutic methods are required to tackle the global issue of neurodegeneration in the future. A better understanding of the potential molecular mechanism causing neurodegeneration can shed light on dysfunctional processes in diseased neurons, which can pave the way to design and synthesize novel targets for early diagnosis during the asymptomatic phase of the disease. Abnormal protein aggregation is a hallmark of neurodegenerative diseases which can hamper transportation of cargoes into axons. Recent evidence suggests that disruption of local protein synthesis has been observed in neurodegenerative diseases. Because of their highly asymmetric structure, highly polarized neurons require trafficking of cargoes from the cell body to different subcellular regions to meet the extensive demands of cellular physiology. Localization of mRNAs and subsequent local translation to corresponding proteins in axons is a mechanism which allows neurons to rapidly respond to external stimuli as well as establishing neuronal networks by synthesizing proteins on demand. Axonal protein synthesis is required for axon guidance, synapse formation and plasticity, axon maintenance and regeneration in response to injury. Different types of excitatory and inhibitory neurons in the central and peripheral nervous systems have been shown to localize mRNA. Rising evidence suggests that the repertoire of localizing mRNA in axons can change during aging, indicating a connection between axonal mRNA trafficking and aging diseases such as neurodegeneration. Here, I briefly review the latest findings on the importance of mRNA localization and local translation in neurons and the consequences of their disruption in neurodegenerative diseases. In addition, I discuss recent evidence that dysregulation of mRNA localization and local protein translation can contribute to the formation of neurodegenerative diseases such as Alzheimer's disease, Amyotrophic Lateral Sclerosis, and Spinal Muscular Atrophy. In addition, I discuss recent findings on mRNAs localizing to mitochondria in neurodegeneration.
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Affiliation(s)
- Mohammad Mofatteh
- Lincoln College, University of OxfordOxford, UK
- Sir William Dunn School of Pathology, Medical Sciences Division, University of OxfordOxford, UK
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23
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Dalla Costa I, Buchanan CN, Zdradzinski MD, Sahoo PK, Smith TP, Thames E, Kar AN, Twiss JL. The functional organization of axonal mRNA transport and translation. Nat Rev Neurosci 2021; 22:77-91. [PMID: 33288912 PMCID: PMC8161363 DOI: 10.1038/s41583-020-00407-7] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2020] [Indexed: 12/13/2022]
Abstract
Axons extend for tremendously long distances from the neuronal soma and make use of localized mRNA translation to rapidly respond to different extracellular stimuli and physiological states. The locally synthesized proteins support many different functions in both developing and mature axons, raising questions about the mechanisms by which local translation is organized to ensure the appropriate responses to specific stimuli. Publications over the past few years have uncovered new mechanisms for regulating the axonal transport and localized translation of mRNAs, with several of these pathways converging on the regulation of cohorts of functionally related mRNAs - known as RNA regulons - that drive axon growth, axon guidance, injury responses, axon survival and even axonal mitochondrial function. Recent advances point to these different regulatory pathways as organizing platforms that allow the axon's proteome to be modulated to meet its physiological needs.
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Affiliation(s)
- Irene Dalla Costa
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Courtney N Buchanan
- 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
| | - Terika P Smith
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Elizabeth Thames
- 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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24
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Pereiro X, Ruzafa N, Urcola JH, Sharma SC, Vecino E. Differential Distribution of RBPMS in Pig, Rat, and Human Retina after Damage. Int J Mol Sci 2020; 21:ijms21239330. [PMID: 33297577 PMCID: PMC7729751 DOI: 10.3390/ijms21239330] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/25/2020] [Accepted: 12/03/2020] [Indexed: 12/24/2022] Open
Abstract
RNA binding protein with multiple splicing (RBPMS) is expressed exclusively in retinal ganglion cells (RGCs) in the retina and can label all RGCs in normal retinas of mice, rats, guinea pigs, rabbits, cats, and monkeys, but its function in these cells is not known. As a result of the limited knowledge regarding RBPMS, we analyzed the expression of RBPMS in the retina of different mammalian species (humans, pigs, and rats), in various stages of development (neonatal and adult) and with different levels of injury (control, hypoxia, and organotypic culture or explants). In control conditions, RBPMS was localized in the RGCs somas in the ganglion cell layer, whereas in hypoxic conditions, it was localized in the RGCs dendrites in the inner plexiform layer. Such differential distributions of RBPMS occurred in all analyzed species, and in adult and neonatal retinas. Furthermore, we demonstrate RBPMS localization in the degenerating RGCs axons in the nerve fiber layer of retinal explants. This is the first evidence regarding the possible transport of RBPMS in response to physiological damage in a mammalian retina. Therefore, RBPMS should be further investigated in relation to its role in axonal and dendritic degeneration.
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Affiliation(s)
- Xandra Pereiro
- Department of Cell Biology and Histology, Experimental Ophthalmo-Biology Group (GOBE), University of the Basque Country UPV/EHU, 48940 Leioa, Vizcaya, Spain; (X.P.); (N.R.); (J.H.U.); (S.C.S.)
| | - Noelia Ruzafa
- Department of Cell Biology and Histology, Experimental Ophthalmo-Biology Group (GOBE), University of the Basque Country UPV/EHU, 48940 Leioa, Vizcaya, Spain; (X.P.); (N.R.); (J.H.U.); (S.C.S.)
| | - J. Haritz Urcola
- Department of Cell Biology and Histology, Experimental Ophthalmo-Biology Group (GOBE), University of the Basque Country UPV/EHU, 48940 Leioa, Vizcaya, Spain; (X.P.); (N.R.); (J.H.U.); (S.C.S.)
- Department of Ophthalmology, Araba University Hospital, 01009 Vitoria, Alava, Spain
| | - Sansar C. Sharma
- Department of Cell Biology and Histology, Experimental Ophthalmo-Biology Group (GOBE), University of the Basque Country UPV/EHU, 48940 Leioa, Vizcaya, Spain; (X.P.); (N.R.); (J.H.U.); (S.C.S.)
- Department of Anatomy and Cell Biology, New York Medical College, Valhalla, NY 10595, USA
| | - Elena Vecino
- Department of Cell Biology and Histology, Experimental Ophthalmo-Biology Group (GOBE), University of the Basque Country UPV/EHU, 48940 Leioa, Vizcaya, Spain; (X.P.); (N.R.); (J.H.U.); (S.C.S.)
- Correspondence:
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25
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SMN protein promotes membrane compartmentalization of ribosomal protein S6 transcript in human fibroblasts. Sci Rep 2020; 10:19000. [PMID: 33149163 PMCID: PMC7643083 DOI: 10.1038/s41598-020-76174-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 09/24/2020] [Indexed: 12/14/2022] Open
Abstract
Alterations of RNA homeostasis can lead to severe pathological conditions. The Survival of Motor Neuron (SMN) protein, which is reduced in Spinal Muscular Atrophy, impacts critical aspects of the RNA life cycle, such as splicing, trafficking, and translation. Increasing evidence points to a potential role of SMN in ribosome biogenesis. Our previous study revealed that SMN promotes membrane-bound ribosomal proteins (RPs), sustaining activity-dependent local translation. Here, we suggest that plasma membrane domains could be a docking site not only for RPs but also for their encoding transcripts. We have shown that SMN knockdown perturbs subcellular localization as well as translation efficiency of RPS6 mRNA. We have also shown that plasma membrane-enriched fractions from human fibroblasts retain RPS6 transcripts in an SMN-dependent manner. Furthermore, we revealed that SMN traffics with RPS6 mRNA promoting its association with caveolin-1, a key component of membrane dynamics. Overall, these findings further support the SMN-mediated crosstalk between plasma membrane dynamics and translation machinery. Importantly, our study points to a potential role of SMN in the ribosome assembly pathway by selective RPs synthesis/localization in both space and time.
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26
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Lauria F, Bernabò P, Tebaldi T, Groen EJN, Perenthaler E, Maniscalco F, Rossi A, Donzel D, Clamer M, Marchioretto M, Omersa N, Orri J, Dalla Serra M, Anderluh G, Quattrone A, Inga A, Gillingwater TH, Viero G. SMN-primed ribosomes modulate the translation of transcripts related to spinal muscular atrophy. Nat Cell Biol 2020; 22:1239-1251. [PMID: 32958857 PMCID: PMC7610479 DOI: 10.1038/s41556-020-00577-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 08/13/2020] [Indexed: 12/20/2022]
Abstract
The contribution of ribosome heterogeneity and ribosome-associated proteins to the molecular control of proteomes in health and disease remains unclear. Here, we demonstrate that survival motor neuron (SMN) protein-the loss of which causes the neuromuscular disease spinal muscular atrophy (SMA)-binds to ribosomes and that this interaction is tissue-dependent. SMN-primed ribosomes are preferentially positioned within the first five codons of a set of mRNAs that are enriched for translational enhancer sequences in the 5' untranslated region (UTR) and rare codons at the beginning of their coding sequence. These SMN-specific mRNAs are associated with neurogenesis, lipid metabolism, ubiquitination, chromatin regulation and translation. Loss of SMN induces ribosome depletion, especially at the beginning of the coding sequence of SMN-specific mRNAs, leading to impairment of proteins that are involved in motor neuron function and stability, including acetylcholinesterase. Thus, SMN plays a crucial role in the regulation of ribosome fluxes along mRNAs encoding proteins that are relevant to SMA pathogenesis.
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Affiliation(s)
- Fabio Lauria
- Institute of Biophysics, CNR Unit at Trento, Trento, Italy
| | - Paola Bernabò
- Institute of Biophysics, CNR Unit at Trento, Trento, Italy
| | - Toma Tebaldi
- Department CIBIO, University of Trento, Trento, Italy
- Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, USA
| | - Ewout Joan Nicolaas Groen
- Edinburgh Medical School, Biomedical Sciences & Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
- Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, Utrecht, the Netherlands
| | - Elena Perenthaler
- Institute of Biophysics, CNR Unit at Trento, Trento, Italy
- Department of Clinical Genetics, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Federica Maniscalco
- Institute of Biophysics, CNR Unit at Trento, Trento, Italy
- Department CIBIO, University of Trento, Trento, Italy
| | | | - Deborah Donzel
- Institute of Biophysics, CNR Unit at Trento, Trento, Italy
| | | | | | - Neža Omersa
- National Institute of Chemistry, Ljubljana, Slovenia
| | - Julia Orri
- Institute of Biophysics, CNR Unit at Trento, Trento, Italy
- La Fundació Jesuïtes Educació, Barcelona, Spain
| | | | | | | | - Alberto Inga
- Department CIBIO, University of Trento, Trento, Italy
| | - Thomas Henry Gillingwater
- Edinburgh Medical School, Biomedical Sciences & Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
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Abstract
It is increasingly recognized that local protein synthesis (LPS) contributes to fundamental aspects of axon biology, in both developing and mature neurons. Mutations in RNA-binding proteins (RBPs), as central players in LPS, and other proteins affecting RNA localization and translation are associated with a range of neurological disorders, suggesting disruption of LPS may be of pathological significance. In this review, we substantiate this hypothesis by examining the link between LPS and key axonal processes, and the implicated pathophysiological consequences of dysregulated LPS. First, we describe how the length and autonomy of axons result in an exceptional reliance on LPS. We next discuss the roles of LPS in maintaining axonal structural and functional polarity and axonal trafficking. We then consider how LPS facilitates the establishment of neuronal connectivity through regulation of axonal branching and pruning, how it mediates axonal survival into adulthood and its involvement in neuronal stress responses.
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Affiliation(s)
- Julie Qiaojin Lin
- UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | | | - Christine E Holt
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
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28
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Shigeoka T, Koppers M, Wong HHW, Lin JQ, Cagnetta R, Dwivedy A, de Freitas Nascimento J, van Tartwijk FW, Ströhl F, Cioni JM, Schaeffer J, Carrington M, Kaminski CF, Jung H, Harris WA, Holt CE. On-Site Ribosome Remodeling by Locally Synthesized Ribosomal Proteins in Axons. Cell Rep 2020; 29:3605-3619.e10. [PMID: 31825839 PMCID: PMC6915326 DOI: 10.1016/j.celrep.2019.11.025] [Citation(s) in RCA: 93] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 09/30/2019] [Accepted: 11/06/2019] [Indexed: 01/19/2023] Open
Abstract
Ribosome assembly occurs mainly in the nucleolus, yet recent studies have revealed robust enrichment and translation of mRNAs encoding many ribosomal proteins (RPs) in axons, far away from neuronal cell bodies. Here, we report a physical and functional interaction between locally synthesized RPs and ribosomes in the axon. We show that axonal RP translation is regulated through a sequence motif, CUIC, that forms an RNA-loop structure in the region immediately upstream of the initiation codon. Using imaging and subcellular proteomics techniques, we show that RPs synthesized in axons join axonal ribosomes in a nucleolus-independent fashion. Inhibition of axonal CUIC-regulated RP translation decreases local translation activity and reduces axon branching in the developing brain, revealing the physiological relevance of axonal RP synthesis in vivo. These results suggest that axonal translation supplies cytoplasmic RPs to maintain/modify local ribosomal function far from the nucleolus in neurons.
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Affiliation(s)
- Toshiaki Shigeoka
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK.
| | - Max Koppers
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Hovy Ho-Wai Wong
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Julie Qiaojin Lin
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Roberta Cagnetta
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Asha Dwivedy
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | | | - Francesca W van Tartwijk
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB3 0AS, UK
| | - Florian Ströhl
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB3 0AS, UK
| | - Jean-Michel Cioni
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Julia Schaeffer
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK
| | - Clemens F Kaminski
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB3 0AS, UK
| | - Hosung Jung
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - William A Harris
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Christine E Holt
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK.
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29
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Guillaud L, El-Agamy SE, Otsuki M, Terenzio M. Anterograde Axonal Transport in Neuronal Homeostasis and Disease. Front Mol Neurosci 2020; 13:556175. [PMID: 33071754 PMCID: PMC7531239 DOI: 10.3389/fnmol.2020.556175] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
Neurons are highly polarized cells with an elongated axon that extends far away from the cell body. To maintain their homeostasis, neurons rely extensively on axonal transport of membranous organelles and other molecular complexes. Axonal transport allows for spatio-temporal activation and modulation of numerous molecular cascades, thus playing a central role in the establishment of neuronal polarity, axonal growth and stabilization, and synapses formation. Anterograde and retrograde axonal transport are supported by various molecular motors, such as kinesins and dynein, and a complex microtubule network. In this review article, we will primarily discuss the molecular mechanisms underlying anterograde axonal transport and its role in neuronal development and maturation, including the establishment of functional synaptic connections. We will then provide an overview of the molecular and cellular perturbations that affect axonal transport and are often associated with axonal degeneration. Lastly, we will relate our current understanding of the role of axonal trafficking concerning anterograde trafficking of mRNA and its involvement in the maintenance of the axonal compartment and disease.
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Affiliation(s)
- Laurent Guillaud
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Sara Emad El-Agamy
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Miki Otsuki
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Marco Terenzio
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
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30
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Turner-Bridger B, Caterino C, Cioni JM. Molecular mechanisms behind mRNA localization in axons. Open Biol 2020; 10:200177. [PMID: 32961072 PMCID: PMC7536069 DOI: 10.1098/rsob.200177] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/01/2020] [Indexed: 12/12/2022] Open
Abstract
Messenger RNA (mRNA) localization allows spatiotemporal regulation of the proteome at the subcellular level. This is observed in the axons of neurons, where mRNA localization is involved in regulating neuronal development and function by orchestrating rapid adaptive responses to extracellular cues and the maintenance of axonal homeostasis through local translation. Here, we provide an overview of the key findings that have broadened our knowledge regarding how specific mRNAs are trafficked and localize to axons. In particular, we review transcriptomic studies investigating mRNA content in axons and the molecular principles underpinning how these mRNAs arrived there, including cis-acting mRNA sequences and trans-acting proteins playing a role. Further, we discuss evidence that links defective axonal mRNA localization and pathological outcomes.
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Affiliation(s)
- Benita Turner-Bridger
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, UK
| | - Cinzia Caterino
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Via Olgettina 60, 20132 Milan, Italy
| | - Jean-Michel Cioni
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Via Olgettina 60, 20132 Milan, Italy
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31
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Briese M, Saal-Bauernschubert L, Lüningschrör P, Moradi M, Dombert B, Surrey V, Appenzeller S, Deng C, Jablonka S, Sendtner M. Loss of Tdp-43 disrupts the axonal transcriptome of motoneurons accompanied by impaired axonal translation and mitochondria function. Acta Neuropathol Commun 2020; 8:116. [PMID: 32709255 PMCID: PMC7379803 DOI: 10.1186/s40478-020-00987-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 07/04/2020] [Indexed: 01/02/2023] Open
Abstract
Protein inclusions containing the RNA-binding protein TDP-43 are a pathological hallmark of amyotrophic lateral sclerosis and other neurodegenerative disorders. The loss of TDP-43 function that is associated with these inclusions affects post-transcriptional processing of RNAs in multiple ways including pre-mRNA splicing, nucleocytoplasmic transport, modulation of mRNA stability and translation. In contrast, less is known about the role of TDP-43 in axonal RNA metabolism in motoneurons. Here we show that depletion of Tdp-43 in primary motoneurons affects axon growth. This defect is accompanied by subcellular transcriptome alterations in the axonal and somatodendritic compartment. The axonal localization of transcripts encoding components of the cytoskeleton, the translational machinery and transcripts involved in mitochondrial energy metabolism were particularly affected by loss of Tdp-43. Accordingly, we observed reduced protein synthesis and disturbed mitochondrial functions in axons of Tdp-43-depleted motoneurons. Treatment with nicotinamide rescued the axon growth defect associated with loss of Tdp-43. These results show that Tdp-43 depletion in motoneurons affects several pathways integral to axon health indicating that loss of TDP-43 function could thus make a major contribution to axonal pathomechanisms in ALS.
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32
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Farias J, Holt CE, Sotelo JR, Sotelo-Silveira JR. Axon microdissection and transcriptome profiling reveals the in vivo RNA content of fully differentiated myelinated motor axons. RNA (NEW YORK, N.Y.) 2020; 26:595-612. [PMID: 32051223 PMCID: PMC7161357 DOI: 10.1261/rna.073700.119] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 01/31/2020] [Indexed: 05/23/2023]
Abstract
Axonal protein synthesis has been shown to play a role in developmental and regenerative growth, as well as in the maintenance of the axoplasm in a steady state. Recent studies have begun to identify the mRNAs localized in axons, which could be translated locally under different conditions. Despite that by now hundreds or thousands of mRNAs have been shown to be localized into the axonal compartment of cultured neurons in vitro, knowledge of which mRNAs are localized in mature myelinated axons is quite limited. With the purpose of characterizing the transcriptome of mature myelinated motor axons of peripheral nervous systems, we modified the axon microdissection method devised by Koenig, enabling the isolation of the axoplasm RNA to perform RNA-seq analysis. The transcriptome analysis indicates that the number of RNAs detected in mature axons is lower in comparison with in vitro data, depleted of glial markers, and enriched in neuronal markers. The mature myelinated axons are enriched for mRNAs related to cytoskeleton, translation, and oxidative phosphorylation. Moreover, it was possible to define core genes present in axons when comparing our data with transcriptomic data of axons grown in different conditions. This work provides evidence that axon microdissection is a valuable method to obtain genome-wide data from mature and myelinated axons of the peripheral nervous system, and could be especially useful for the study of axonal involvement in neurodegenerative pathologies of motor neurons such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophies (SMA).
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Affiliation(s)
- Joaquina Farias
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, 11600, Uruguay
- Departamento de Proteínas y Ácidos Nucléicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, 11600, Uruguay
| | - Christine E Holt
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, CB2 3DY, United Kingdom
| | - José R Sotelo
- Departamento de Proteínas y Ácidos Nucléicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, 11600, Uruguay
| | - José R Sotelo-Silveira
- Departamento de Genómica, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, 11600, Uruguay
- Departamento de Biología Celular y Molecular, Facultad de Ciencias, Universidad de la República, Montevideo, 11400, Uruguay
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33
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Suzuki N, Akiyama T, Warita H, Aoki M. Omics Approach to Axonal Dysfunction of Motor Neurons in Amyotrophic Lateral Sclerosis (ALS). Front Neurosci 2020; 14:194. [PMID: 32269505 PMCID: PMC7109447 DOI: 10.3389/fnins.2020.00194] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/24/2020] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an intractable adult-onset neurodegenerative disease that leads to the loss of upper and lower motor neurons (MNs). The long axons of MNs become damaged during the early stages of ALS. Genetic and pathological analyses of ALS patients have revealed dysfunction in the MN axon homeostasis. However, the molecular pathomechanism for the degeneration of axons in ALS has not been fully elucidated. This review provides an overview of the proposed axonal pathomechanisms in ALS, including those involving the neuronal cytoskeleton, cargo transport within axons, axonal energy supply, clearance of junk protein, neuromuscular junctions (NMJs), and aberrant axonal branching. To improve understanding of the global changes in axons, the review summarizes omics analyses of the axonal compartments of neurons in vitro and in vivo, including a motor nerve organoid approach that utilizes microfluidic devices developed by this research group. The review also discusses the relevance of intra-axonal transcription factors frequently identified in these omics analyses. Local axonal translation and the relationship among these pathomechanisms should be pursued further. The development of novel strategies to analyze axon fractions provides a new approach to establishing a detailed understanding of resilience of long MN and MN pathology in ALS.
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Affiliation(s)
- Naoki Suzuki
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan.,Department of Neurology, Shodo-kai Southern Tohoku General Hospital, Miyagi, Japan
| | - Tetsuya Akiyama
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
| | - Hitoshi Warita
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
| | - Masashi Aoki
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
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von Kügelgen N, Chekulaeva M. Conservation of a core neurite transcriptome across neuronal types and species. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 11:e1590. [PMID: 32059075 DOI: 10.1002/wrna.1590] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/20/2020] [Accepted: 01/23/2020] [Indexed: 12/23/2022]
Abstract
The intracellular localization of mRNAs allows neurons to control gene expression in neurite extensions (axons and dendrites) and respond rapidly to local stimuli. This plays an important role in diverse processes including neuronal growth and synaptic plasticity, which in turn serves as a foundation for learning and memory. Recent high-throughput analyses have revealed that neurites contain hundreds to thousands of mRNAs, but an analysis comparing the transcriptomes derived from these studies has been lacking. Here we analyze 20 datasets pertaining to neuronal mRNA localization across species and neuronal types and identify a conserved set of mRNAs that had robustly localized to neurites in a high number of the studies. The set includes mRNAs encoding for ribosomal proteins and other components of the translation machinery, mitochondrial proteins, cytoskeletal components, and proteins associated with neurite formation. Our combinatorial analysis provides a unique resource for future hypothesis-driven research. This article is categorized under: RNA Export and Localization > RNA Localization RNA Evolution and Genomics > Computational Analyses of RNA RNA Methods > RNA Analyses in Cells.
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Affiliation(s)
- Nicolai von Kügelgen
- Non-coding RNAs and Mechanisms of Cytoplasmic Gene Regulation, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Marina Chekulaeva
- Non-coding RNAs and Mechanisms of Cytoplasmic Gene Regulation, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
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35
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Tejero R, Balk S, Franco-Espin J, Ojeda J, Hennlein L, Drexl H, Dombert B, Clausen JD, Torres-Benito L, Saal-Bauernschubert L, Blum R, Briese M, Appenzeller S, Tabares L, Jablonka S. R-Roscovitine Improves Motoneuron Function in Mouse Models for Spinal Muscular Atrophy. iScience 2020; 23:100826. [PMID: 31981925 PMCID: PMC6992996 DOI: 10.1016/j.isci.2020.100826] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 08/08/2019] [Accepted: 01/06/2020] [Indexed: 12/27/2022] Open
Abstract
Neurotransmission defects and motoneuron degeneration are hallmarks of spinal muscular atrophy, a monogenetic disease caused by the deficiency of the SMN protein. In the present study, we show that systemic application of R-Roscovitine, a Cav2.1/Cav2.2 channel modifier and a cyclin-dependent kinase 5 (Cdk-5) inhibitor, significantly improved survival of SMA mice. In addition, R-Roscovitine increased Cav2.1 channel density and sizes of the motor endplates. In vitro, R-Roscovitine restored axon lengths and growth cone sizes of Smn-deficient motoneurons corresponding to enhanced spontaneous Ca2+ influx and elevated Cav2.2 channel cluster formations independent of its capability to inhibit Cdk-5. Acute application of R-Roscovitine at the neuromuscular junction significantly increased evoked neurotransmitter release, increased the frequency of spontaneous miniature potentials, and lowered the activation threshold of silent terminals. These data indicate that R-Roscovitine improves Ca2+ signaling and Ca2+ homeostasis in Smn-deficient motoneurons, which is generally crucial for motoneuron differentiation, maturation, and function. R-Roscovitine prolongs survival of SMA mice R-Roscovitine increases Ca2+ influx and growth cone size of SMA motoneurons R-Roscovitine beneficially affects neurotransmission in SMA motor nerve terminals R-Roscovitine wakes up dormant synapses of SMA motoneurons
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Affiliation(s)
- Rocio Tejero
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain
| | - Stefanie Balk
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Julio Franco-Espin
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain
| | - Jorge Ojeda
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain
| | - Luisa Hennlein
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Hans Drexl
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Benjamin Dombert
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Jan-Dierk Clausen
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Laura Torres-Benito
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain
| | | | - Robert Blum
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Michael Briese
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Silke Appenzeller
- Comprehensive Cancer Center Mainfranken, University Hospital Würzburg, 97080 Würzburg, Germany; Core Unit SysMed, University of Würzburg, 97080 Würzburg, Germany
| | - Lucia Tabares
- Department of Medical Physiology and Biophysics, School of Medicine, University of Seville, 41009 Seville, Spain.
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany.
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36
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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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37
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Kaifer KA, Villalón E, O'Brien BS, Sison SL, Smith CE, Simon ME, Marquez J, O'Day S, Hopkins AE, Neff R, Rindt H, Ebert AD, Lorson CL. AAV9-mediated delivery of miR-23a reduces disease severity in Smn2B/-SMA model mice. Hum Mol Genet 2019; 28:3199-3210. [PMID: 31211843 PMCID: PMC6859438 DOI: 10.1093/hmg/ddz142] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 05/24/2019] [Accepted: 06/10/2019] [Indexed: 12/20/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a neuromuscular disease caused by deletions or mutations in survival motor neuron 1 (SMN1). The molecular mechanisms underlying motor neuron degeneration in SMA remain elusive, as global cellular dysfunction obscures the identification and characterization of disease-relevant pathways and potential therapeutic targets. Recent reports have implicated microRNA (miRNA) dysregulation as a potential contributor to the pathological mechanism in SMA. To characterize miRNAs that are differentially regulated in SMA, we profiled miRNA levels in SMA induced pluripotent stem cell (iPSC)-derived motor neurons. From this array, miR-23a downregulation was identified selectively in SMA motor neurons, consistent with previous reports where miR-23a functioned in neuroprotective and muscle atrophy-antagonizing roles. Reintroduction of miR-23a expression in SMA patient iPSC-derived motor neurons protected against degeneration, suggesting a potential miR-23a-specific disease-modifying effect. To assess this activity in vivo, miR-23a was expressed using a self-complementary adeno-associated virus serotype 9 (scAAV9) viral vector in the Smn2B/- SMA mouse model. scAAV9-miR-23a significantly reduced the pathology in SMA mice, including increased motor neuron size, reduced neuromuscular junction pathology, increased muscle fiber area, and extended survival. These experiments demonstrate that miR-23a is a novel protective modifier of SMA, warranting further characterization of miRNA dysfunction in SMA.
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Affiliation(s)
- Kevin A Kaifer
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Eric Villalón
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Benjamin S O'Brien
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Samantha L Sison
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Caley E Smith
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Madeline E Simon
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Jose Marquez
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Siri O'Day
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Abigail E Hopkins
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Rachel Neff
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Hansjörg Rindt
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Allison D Ebert
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Christian L Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
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38
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Nijssen J, Aguila J, Hoogstraaten R, Kee N, Hedlund E. Axon-Seq Decodes the Motor Axon Transcriptome and Its Modulation in Response to ALS. Stem Cell Reports 2019; 11:1565-1578. [PMID: 30540963 PMCID: PMC6294264 DOI: 10.1016/j.stemcr.2018.11.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 11/06/2018] [Accepted: 11/06/2018] [Indexed: 12/11/2022] Open
Abstract
Spinal motor axons traverse large distances to innervate target muscles, thus requiring local control of cellular events for proper functioning. To interrogate axon-specific processes we developed Axon-seq, a refined method incorporating microfluidics, RNA sequencing (RNA-seq), and bioinformatic quality control. We show that the axonal transcriptome is distinct from that of somas and contains fewer genes. We identified 3,500-5,000 transcripts in mouse and human stem cell-derived spinal motor axons, most of which are required for oxidative energy production and ribogenesis. Axons contained transcription factor mRNAs, e.g., Ybx1, with implications for local functions. As motor axons degenerate in amyotrophic lateral sclerosis (ALS), we investigated their response to the SOD1G93A mutation, identifying 121 ALS-dysregulated transcripts. Several of these are implicated in axonal function, including Nrp1, Dbn1, and Nek1, a known ALS-causing gene. In conclusion, Axon-seq provides an improved method for RNA-seq of axons, increasing our understanding of peripheral axon biology and identifying therapeutic targets in motor neuron disease.
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Affiliation(s)
- Jik Nijssen
- Department of Neuroscience, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Julio Aguila
- Department of Neuroscience, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Rein Hoogstraaten
- Department of Neuroscience, Karolinska Institutet, Stockholm 171 77, Sweden; Department of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht 3984 CG, Netherlands
| | - Nigel Kee
- Department of Neuroscience, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Eva Hedlund
- Department of Neuroscience, Karolinska Institutet, Stockholm 171 77, Sweden.
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39
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Quinlan KA, Reedich EJ, Arnold WD, Puritz AC, Cavarsan CF, Heckman CJ, DiDonato CJ. Hyperexcitability precedes motoneuron loss in the Smn2B/- mouse model of spinal muscular atrophy. J Neurophysiol 2019; 122:1297-1311. [PMID: 31365319 DOI: 10.1152/jn.00652.2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Spinal motoneuron dysfunction and loss are pathological hallmarks of the neuromuscular disease spinal muscular atrophy (SMA). Changes in motoneuron physiological function precede cell death, but how these alterations vary with disease severity and motoneuron maturational state is unknown. To address this question, we assessed the electrophysiology and morphology of spinal motoneurons of presymptomatic Smn2B/- mice older than 1 wk of age and tracked the timing of motor unit loss in this model using motor unit number estimation (MUNE). In contrast to other commonly used SMA mouse models, Smn2B/- mice exhibit more typical postnatal development until postnatal day (P)11 or 12 and have longer survival (~3 wk of age). We demonstrate that Smn2B/- motoneuron hyperexcitability, marked by hyperpolarization of the threshold voltage for action potential firing, was present at P9-10 and preceded the loss of motor units. Using MUNE studies, we determined that motor unit loss in this mouse model occurred 2 wk after birth. Smn2B/- motoneurons were also larger in size, which may reflect compensatory changes taking place during postnatal development. This work suggests that motoneuron hyperexcitability, marked by a reduced threshold for action potential firing, is a pathological change preceding motoneuron loss that is common to multiple models of severe SMA with different motoneuron maturational states. Our results indicate voltage-gated sodium channel activity may be altered in the disease process.NEW & NOTEWORTHY Changes in spinal motoneuron physiologic function precede cell death in spinal muscular atrophy (SMA), but how they vary with maturational state and disease severity remains unknown. This study characterized motoneuron and neuromuscular electrophysiology from the Smn2B/- model of SMA. Motoneurons were hyperexcitable at postnatal day (P)9-10, and specific electrophysiological changes in Smn2B/- motoneurons preceded functional motor unit loss at P14, as determined by motor unit number estimation studies.
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Affiliation(s)
- K A Quinlan
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island.,George and Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, Rhode Island.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - E J Reedich
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Human Molecular Genetics Program, Stanley Manne Children's Research Institute at Ann & Robert H. Lurie Children's Hospital, Chicago, Illinois
| | - W D Arnold
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus, Ohio.,Department of Physical Medicine and Rehabilitation, The Ohio State University Wexner Medical Center, Columbus, Ohio.,Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, Ohio.,Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - A C Puritz
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - C F Cavarsan
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, Rhode Island.,George and Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, Rhode Island
| | - C J Heckman
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - C J DiDonato
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Human Molecular Genetics Program, Stanley Manne Children's Research Institute at Ann & Robert H. Lurie Children's Hospital, Chicago, Illinois
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40
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Nijssen J, Aguila J, Hedlund E. Axon-seq for in Depth Analysis of the RNA Content of Neuronal Processes. Bio Protoc 2019; 9:e3312. [PMID: 33654821 DOI: 10.21769/bioprotoc.3312] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/24/2019] [Accepted: 07/22/2019] [Indexed: 11/02/2022] Open
Abstract
Neuronal processes have an RNA composition that is distinct from the cell body. Therefore, to fully understand neuronal biology in health and disease we need to study both somas, dendrites and axons. Here we describe a detailed protocol of a newly refined method, Axon-seq, for RNA sequencing of axons (and dendrites) grown in isolation using single microfluidic devices. We also detail how to generate motor neurons from mouse and human pluripotent stem cells for sequencing, but Axon-seq is applicable to any neuronal cell. In Axon-seq, the axons are recruited through a growth factor gradient, lysed and directly processed to cDNA without RNA isolation. A careful bioinformatic step ensures that any soma-contaminated samples are easily identified and removed.
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Affiliation(s)
- Jik Nijssen
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Julio Aguila
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Eva Hedlund
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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41
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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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42
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Badiola-Mateos M, Hervera A, Del Río JA, Samitier J. Challenges and Future Prospects on 3D in-vitro Modeling of the Neuromuscular Circuit. Front Bioeng Biotechnol 2018; 6:194. [PMID: 30622944 PMCID: PMC6297173 DOI: 10.3389/fbioe.2018.00194] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/27/2018] [Indexed: 12/18/2022] Open
Abstract
Movement of skeletal-muscle fibers is generated by the coordinated action of several cells taking part within the locomotion circuit (motoneurons, sensory-neurons, Schwann cells, astrocytes, microglia, and muscle-cells). Failures in any part of this circuit could impede or hinder coordinated muscle movement and cause a neuromuscular disease (NMD) or determine its severity. Studying fragments of the circuit cannot provide a comprehensive and complete view of the pathological process. We trace the historic developments of studies focused on in-vitro modeling of the spinal-locomotion circuit and how bioengineered innovative technologies show advantages for an accurate mimicking of physiological conditions of spinal-locomotion circuit. New developments on compartmentalized microfluidic culture systems (cμFCS), the use of human induced pluripotent stem cells (hiPSCs) and 3D cell-cultures are analyzed. We finally address limitations of current study models and three main challenges on neuromuscular studies: (i) mimic the whole spinal-locomotion circuit including all cell-types involved and the evaluation of independent and interdependent roles of each one; (ii) mimic the neurodegenerative response of mature neurons in-vitro as it occurs in-vivo; and (iii) develop, tune, implement, and combine cμFCS, hiPSC, and 3D-culture technologies to ultimately create patient-specific complete, translational, and reliable NMD in-vitro model. Overcoming these challenges would significantly facilitate understanding the events taking place in NMDs and accelerate the process of finding new therapies.
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Affiliation(s)
- Maider Badiola-Mateos
- Institute for Bioengineering of Catalonia-Barcelona Institute of Science and Technology, Barcelona, Spain.,Department of Electronics and Biomedical Engineering, Faculty of Physics, Universitat de Barcelona, Barcelona, Spain
| | - Arnau Hervera
- Institute for Bioengineering of Catalonia-Barcelona Institute of Science and Technology, Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Faculty of Biology, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Barcelona, Spain.,Institut de Neurociències de la Universitat de Barcelona, Barcelona, Spain
| | - José Antonio Del Río
- Institute for Bioengineering of Catalonia-Barcelona Institute of Science and Technology, Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Faculty of Biology, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Barcelona, Spain.,Institut de Neurociències de la Universitat de Barcelona, Barcelona, Spain
| | - Josep Samitier
- Institute for Bioengineering of Catalonia-Barcelona Institute of Science and Technology, Barcelona, Spain.,Department of Electronics and Biomedical Engineering, Faculty of Physics, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Madrid, Spain
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43
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Šoltić D, Bowerman M, Stock J, Shorrock HK, Gillingwater TH, Fuller HR. Multi-Study Proteomic and Bioinformatic Identification of Molecular Overlap between Amyotrophic Lateral Sclerosis (ALS) and Spinal Muscular Atrophy (SMA). Brain Sci 2018; 8:brainsci8120212. [PMID: 30518112 PMCID: PMC6315439 DOI: 10.3390/brainsci8120212] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/28/2018] [Accepted: 11/30/2018] [Indexed: 12/24/2022] Open
Abstract
Unravelling the complex molecular pathways responsible for motor neuron degeneration in amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) remains a persistent challenge. Interest is growing in the potential molecular similarities between these two diseases, with the hope of better understanding disease pathology for the guidance of therapeutic development. The aim of this study was to conduct a comparative analysis of published proteomic studies of ALS and SMA, seeking commonly dysregulated molecules to be prioritized as future therapeutic targets. Fifteen proteins were found to be differentially expressed in two or more proteomic studies of both ALS and SMA, and bioinformatics analysis identified over-representation of proteins known to associate in vesicles and molecular pathways, including metabolism of proteins and vesicle-mediated transport—both of which converge on endoplasmic reticulum (ER)-Golgi trafficking processes. Calreticulin, a calcium-binding chaperone found in the ER, was associated with both pathways and we independently confirm that its expression was decreased in spinal cords from SMA and increased in spinal cords from ALS mice. Together, these findings offer significant insights into potential common targets that may help to guide the development of new therapies for both diseases.
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Affiliation(s)
- Darija Šoltić
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
| | - Melissa Bowerman
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
| | - Joanne Stock
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
| | - Hannah K. Shorrock
- Biomedical Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh EH8 9AG, UK; (H.K.S.); (T.H.G.)
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Thomas H. Gillingwater
- Biomedical Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh EH8 9AG, UK; (H.K.S.); (T.H.G.)
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Heidi R. Fuller
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
- Correspondence: ; Tel.: +44-169-140-4693; Fax: +44-169-140-4065
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44
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Khalil B, Morderer D, Price PL, Liu F, Rossoll W. mRNP assembly, axonal transport, and local translation in neurodegenerative diseases. Brain Res 2018; 1693:75-91. [PMID: 29462608 PMCID: PMC5997521 DOI: 10.1016/j.brainres.2018.02.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/31/2018] [Accepted: 02/13/2018] [Indexed: 12/12/2022]
Abstract
The development, maturation, and maintenance of the mammalian nervous system rely on complex spatiotemporal patterns of gene expression. In neurons, this is achieved by the expression of differentially localized isoforms and specific sets of mRNA-binding proteins (mRBPs) that regulate RNA processing, mRNA trafficking, and local protein synthesis at remote sites within dendrites and axons. There is growing evidence that axons contain a specialized transcriptome and are endowed with the machinery that allows them to rapidly alter their local proteome via local translation and protein degradation. This enables axons to quickly respond to changes in their environment during development, and to facilitate axon regeneration and maintenance in adult organisms. Aside from providing autonomy to neuronal processes, local translation allows axons to send retrograde injury signals to the cell soma. In this review, we discuss evidence that disturbances in mRNP transport, granule assembly, axonal localization, and local translation contribute to pathology in various neurodegenerative diseases, including spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease (AD).
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Affiliation(s)
- Bilal Khalil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Dmytro Morderer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Phillip L Price
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA; Department of Cell Biology, Emory University, Atlanta, GA 30322 USA
| | - Feilin Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA; Eye Center, The Second Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Wilfried Rossoll
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA.
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45
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Ravanidis S, Kattan FG, Doxakis E. Unraveling the Pathways to Neuronal Homeostasis and Disease: Mechanistic Insights into the Role of RNA-Binding Proteins and Associated Factors. Int J Mol Sci 2018; 19:ijms19082280. [PMID: 30081499 PMCID: PMC6121432 DOI: 10.3390/ijms19082280] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 07/26/2018] [Accepted: 07/31/2018] [Indexed: 12/13/2022] Open
Abstract
The timing, dosage and location of gene expression are fundamental determinants of brain architectural complexity. In neurons, this is, primarily, achieved by specific sets of trans-acting RNA-binding proteins (RBPs) and their associated factors that bind to specific cis elements throughout the RNA sequence to regulate splicing, polyadenylation, stability, transport and localized translation at both axons and dendrites. Not surprisingly, misregulation of RBP expression or disruption of its function due to mutations or sequestration into nuclear or cytoplasmic inclusions have been linked to the pathogenesis of several neuropsychiatric and neurodegenerative disorders such as fragile-X syndrome, autism spectrum disorders, spinal muscular atrophy, amyotrophic lateral sclerosis and frontotemporal dementia. This review discusses the roles of Pumilio, Staufen, IGF2BP, FMRP, Sam68, CPEB, NOVA, ELAVL, SMN, TDP43, FUS, TAF15, and TIA1/TIAR in RNA metabolism by analyzing their specific molecular and cellular function, the neurological symptoms associated with their perturbation, and their axodendritic transport/localization along with their target mRNAs as part of larger macromolecular complexes termed ribonucleoprotein (RNP) granules.
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Affiliation(s)
- Stylianos Ravanidis
- Basic Sciences Division I, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece.
| | - Fedon-Giasin Kattan
- Basic Sciences Division I, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece.
| | - Epaminondas Doxakis
- Basic Sciences Division I, Biomedical Research Foundation, Academy of Athens, 11527 Athens, Greece.
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46
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Beattie CE, Kolb SJ. Spinal muscular atrophy: Selective motor neuron loss and global defect in the assembly of ribonucleoproteins. Brain Res 2018; 1693:92-97. [DOI: 10.1016/j.brainres.2018.02.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 02/10/2018] [Accepted: 02/15/2018] [Indexed: 12/13/2022]
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47
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Lee SJ, Oses-Prieto JA, Kawaguchi R, Sahoo PK, Kar AN, Rozenbaum M, Oliver D, Chand S, Ji H, Shtutman M, Miller-Randolph S, Taylor RJ, Fainzilber M, Coppola G, Burlingame AL, Twiss JL. hnRNPs Interacting with mRNA Localization Motifs Define Axonal RNA Regulons. Mol Cell Proteomics 2018; 17:2091-2106. [PMID: 30038033 DOI: 10.1074/mcp.ra118.000603] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 07/05/2018] [Indexed: 12/30/2022] Open
Abstract
mRNA translation in axons enables neurons to introduce new proteins at sites distant from their cell body. mRNA-protein interactions drive this post-transcriptional regulation, yet knowledge of RNA binding proteins (RBP) in axons is limited. Here we used proteomics to identify RBPs interacting with the axonal localizing motifs of Nrn1, Hmgb1, Actb, and Gap43 mRNAs, revealing many novel RBPs in axons. Interestingly, no RBP is shared between all four RNA motifs, suggesting graded and overlapping specificities of RBP-mRNA pairings. A systematic assessment of axonal mRNAs interacting with hnRNP H1, hnRNP F, and hnRNP K, proteins that bound with high specificity to Nrn1 and Hmgb1, revealed that axonal mRNAs segregate into axon growth-associated RNA regulons based on hnRNP interactions. Axotomy increases axonal transport of hnRNPs H1, F, and K, depletion of these hnRNPs decreases axon growth and reduces axonal mRNA levels and axonal protein synthesis. Thus, subcellular hnRNP-interacting RNA regulons support neuronal growth and regeneration.
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Affiliation(s)
- Seung Joon Lee
- From the ‡Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208
| | - Juan A Oses-Prieto
- §Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, 94158
| | - Riki Kawaguchi
- ¶Department of Psychiatry and Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095
| | - Pabitra K Sahoo
- From the ‡Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208
| | - Amar N Kar
- From the ‡Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208
| | - Meir Rozenbaum
- ‖Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - David Oliver
- **Department of Drug Discovery and Biomedical Sciences, University of South Carolina, Columbia, SC, 29208
| | - Shreya Chand
- §Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, 94158
| | - Hao Ji
- **Department of Drug Discovery and Biomedical Sciences, University of South Carolina, Columbia, SC, 29208
| | - Michael Shtutman
- **Department of Drug Discovery and Biomedical Sciences, University of South Carolina, Columbia, SC, 29208
| | | | - Ross J Taylor
- From the ‡Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208
| | - Mike Fainzilber
- ‖Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Giovanni Coppola
- ¶Department of Psychiatry and Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095.,‡‡Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, 90095
| | - Alma L Burlingame
- §Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, 94158
| | - Jeffery L Twiss
- From the ‡Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208;
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48
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Walker CA, Randolph LK, Matute C, Alberdi E, Baleriola J, Hengst U. Aβ 1-42 triggers the generation of a retrograde signaling complex from sentinel mRNAs in axons. EMBO Rep 2018; 19:e45435. [PMID: 29759981 PMCID: PMC6030698 DOI: 10.15252/embr.201745435] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 04/20/2018] [Accepted: 04/24/2018] [Indexed: 11/09/2022] Open
Abstract
Neurons frequently encounter neurodegenerative signals first in their periphery. For example, exposure of axons to oligomeric Aβ1-42 is sufficient to induce changes in the neuronal cell body that ultimately lead to degeneration. Currently, it is unclear how the information about the neurodegenerative insult is transmitted to the soma. Here, we find that the translation of pre-localized but normally silenced sentinel mRNAs in axons is induced within minutes of Aβ1-42 addition in a Ca2+-dependent manner. This immediate protein synthesis following Aβ1-42 exposure generates a retrograde signaling complex including vimentin. Inhibition of the immediate protein synthesis, knock-down of axonal vimentin synthesis, or inhibition of dynein-dependent transport to the soma prevented the normal cell body response to Aβ1-42 These results establish that CNS axons react to neurodegenerative insults via the local translation of sentinel mRNAs encoding components of a retrograde signaling complex that transmit the information about the event to the neuronal soma.
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Affiliation(s)
- Chandler A Walker
- Integrated Program in Cellular, Molecular and Biomedical Studies, Columbia University Irving Medical Center, New York, NY, USA
| | - Lisa K Randolph
- Doctoral Program in Neurobiology and Behavior, Columbia University, New York, NY, USA
| | - Carlos Matute
- Achucarro Basque Center for Neuroscience, Leioa, Spain
- Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), Leioa, Spain
- Centro de Investigación en Red de Enfermedades Neurodegenerativas (CIBERNED), Leioa, Spain
| | - Elena Alberdi
- Achucarro Basque Center for Neuroscience, Leioa, Spain
- Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), Leioa, Spain
- Centro de Investigación en Red de Enfermedades Neurodegenerativas (CIBERNED), Leioa, Spain
| | - Jimena Baleriola
- Achucarro Basque Center for Neuroscience, Leioa, Spain
- IKERBASQUE Basque Foundation for Science, Bilbao, Spain
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, NY, USA
| | - Ulrich Hengst
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, NY, USA
- Department of Pathology & Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
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49
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Sahoo PK, Smith DS, Perrone-Bizzozero N, Twiss JL. Axonal mRNA transport and translation at a glance. J Cell Sci 2018; 131:jcs196808. [PMID: 29654160 PMCID: PMC6518334 DOI: 10.1242/jcs.196808] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Localization and translation of mRNAs within different subcellular domains provides an important mechanism to spatially and temporally introduce new proteins in polarized cells. Neurons make use of this localized protein synthesis during initial growth, regeneration and functional maintenance of their axons. Although the first evidence for protein synthesis in axons dates back to 1960s, improved methodologies, including the ability to isolate axons to purity, highly sensitive RNA detection methods and imaging approaches, have shed new light on the complexity of the transcriptome of the axon and how it is regulated. Moreover, these efforts are now uncovering new roles for locally synthesized proteins in neurological diseases and injury responses. In this Cell Science at a Glance article and the accompanying poster, we provide an overview of how axonal mRNA transport and translation are regulated, and discuss their emerging links to neurological disorders and neural repair.
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Affiliation(s)
- Pabitra K Sahoo
- Department of Biological Sciences, University of South Carolina, 715 Sumter St., CLS 401, Columbia, SC 29208, USA
| | - Deanna S Smith
- Department of Biological Sciences, University of South Carolina, 715 Sumter St., CLS 401, Columbia, SC 29208, USA
| | - Nora Perrone-Bizzozero
- Department of Neurosciences, University of New Mexico School of Medicine, 1 University of New Mexico, MSC08 4740, Albuquerque, NM 87131, USA
| | - Jeffery L Twiss
- Department of Biological Sciences, University of South Carolina, 715 Sumter St., CLS 401, Columbia, SC 29208, USA
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50
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Chuang CF, King CE, Ho BW, Chien KY, Chang YC. Unbiased Proteomic Study of the Axons of Cultured Rat Cortical Neurons. J Proteome Res 2018; 17:1953-1966. [DOI: 10.1021/acs.jproteome.8b00069] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
| | | | | | - Kun-Yi Chien
- Department of Biochemistry and Molecular Biology, College of Medicine, Chang Gung University, Taoyuan City 33302, Taiwan
- Clinical Proteomics Core Laboratory, Linkou Chang Gung Memorial Hospital, Taoyuan City 33305, Taiwan
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