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Naskar A, Nayak A, Salaikumaran MR, Vishal SS, Gopal PP. Phase separation and pathologic transitions of RNP condensates in neurons: implications for amyotrophic lateral sclerosis, frontotemporal dementia and other neurodegenerative disorders. Front Mol Neurosci 2023; 16:1242925. [PMID: 37720552 PMCID: PMC10502346 DOI: 10.3389/fnmol.2023.1242925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/21/2023] [Indexed: 09/19/2023] Open
Abstract
Liquid-liquid phase separation results in the formation of dynamic biomolecular condensates, also known as membrane-less organelles, that allow for the assembly of functional compartments and higher order structures within cells. Multivalent, reversible interactions between RNA-binding proteins (RBPs), including FUS, TDP-43, and hnRNPA1, and/or RNA (e.g., RBP-RBP, RBP-RNA, RNA-RNA), result in the formation of ribonucleoprotein (RNP) condensates, which are critical for RNA processing, mRNA transport, stability, stress granule assembly, and translation. Stress granules, neuronal transport granules, and processing bodies are examples of cytoplasmic RNP condensates, while the nucleolus and Cajal bodies are representative nuclear RNP condensates. In neurons, RNP condensates promote long-range mRNA transport and local translation in the dendrites and axon, and are essential for spatiotemporal regulation of gene expression, axonal integrity and synaptic function. Mutations of RBPs and/or pathologic mislocalization and aggregation of RBPs are hallmarks of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease. ALS/FTD-linked mutations of RBPs alter the strength and reversibility of multivalent interactions with other RBPs and RNAs, resulting in aberrant phase transitions. These aberrant RNP condensates have detrimental functional consequences on mRNA stability, localization, and translation, and ultimately lead to compromised axonal integrity and synaptic function in disease. Pathogenic protein aggregation is dependent on various factors, and aberrant dynamically arrested RNP condensates may serve as an initial nucleation step for pathologic aggregate formation. Recent studies have focused on identifying mechanisms by which neurons resolve phase transitioned condensates to prevent the formation of pathogenic inclusions/aggregates. The present review focuses on the phase separation of neurodegenerative disease-linked RBPs, physiological functions of RNP condensates, and the pathologic role of aberrant phase transitions in neurodegenerative disease, particularly ALS/FTD. We also examine cellular mechanisms that contribute to the resolution of aberrant condensates in neurons, and potential therapeutic approaches to resolve aberrantly phase transitioned condensates at a molecular level.
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Affiliation(s)
- Aditi Naskar
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Asima Nayak
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | | | - Sonali S. Vishal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Pallavi P. Gopal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale School of Medicine, New Haven, CT, United States
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Bagyinszky E, Hulme J, An SSA. Studies of Genetic and Proteomic Risk Factors of Amyotrophic Lateral Sclerosis Inspire Biomarker Development and Gene Therapy. Cells 2023; 12:1948. [PMID: 37566027 PMCID: PMC10417729 DOI: 10.3390/cells12151948] [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: 06/21/2023] [Revised: 07/21/2023] [Accepted: 07/25/2023] [Indexed: 08/12/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease affecting the upper and lower motor neurons, leading to muscle weakness, motor impairments, disabilities and death. Approximately 5-10% of ALS cases are associated with positive family history (familial ALS or fALS), whilst the remainder are sporadic (sporadic ALS, sALS). At least 50 genes have been identified as causative or risk factors for ALS. Established pathogenic variants include superoxide dismutase type 1 (SOD1), chromosome 9 open reading frame 72 (c9orf72), TAR DNA Binding Protein (TARDBP), and Fused In Sarcoma (FUS); additional ALS-related genes including Charged Multivesicular Body Protein 2B (CHMP2B), Senataxin (SETX), Sequestosome 1 (SQSTM1), TANK Binding Kinase 1 (TBK1) and NIMA Related Kinase 1 (NEK1), have been identified. Mutations in these genes could impair different mechanisms, including vesicle transport, autophagy, and cytoskeletal or mitochondrial functions. So far, there is no effective therapy against ALS. Thus, early diagnosis and disease risk predictions remain one of the best options against ALS symptomologies. Proteomic biomarkers, microRNAs, and extracellular vehicles (EVs) serve as promising tools for disease diagnosis or progression assessment. These markers are relatively easy to obtain from blood or cerebrospinal fluids and can be used to identify potential genetic causative and risk factors even in the preclinical stage before symptoms appear. In addition, antisense oligonucleotides and RNA gene therapies have successfully been employed against other diseases, such as childhood-onset spinal muscular atrophy (SMA), which could also give hope to ALS patients. Therefore, an effective gene and biomarker panel should be generated for potentially "at risk" individuals to provide timely interventions and better treatment outcomes for ALS patients as soon as possible.
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Affiliation(s)
- Eva Bagyinszky
- Graduate School of Environment Department of Industrial and Environmental Engineering, Gachon University, Seongnam-si 13120, Republic of Korea;
| | - John Hulme
- Graduate School of Environment Department of Industrial and Environmental Engineering, Gachon University, Seongnam-si 13120, Republic of Korea;
| | - Seong Soo A. An
- Department of Bionano Technology, Gachon University, Seongnam-si 13120, Republic of Korea
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3
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Honda H, Yoshimura M, Arahata H, Yagita K, Sadashima S, Hamasaki H, Shijo M, Koyama S, Noguchi H, Sasagasako N. Mutated FUS in familial amyotrophic lateral sclerosis involves multiple hnRNPs in the formation of neuronal cytoplasmic inclusions. J Neuropathol Exp Neurol 2023; 82:231-241. [PMID: 36592411 DOI: 10.1093/jnen/nlac124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Fused in sarcoma (FUS), coded by FUS, is a heterogeneous nuclear ribonucleoprotein (hnRNP). FUS mutations are among the major mutations in familial amyotrophic lateral sclerosis (ALS-FUS: ALS6). The pathological hallmarks of ALS-FUS are FUS-positive neuronal cytoplasmic inclusions (NCI). We examined various hnRNPs in FUS NCIs in the hippocampus in ALS-FUS cases with different FUS mutations (Case 1, H517P; Case 2, R521C). We also examined TDP43-positive NCIs in sporadic ALS hippocampi. Immunohistochemistry was performed using primary antibodies against FUS, p-TDP43, TDP43, hnRNPA1, hnRNPD, PCBP1, PCBP2, and p62. Numerous FUS inclusions were found in the hippocampal granule and pyramidal cell layers. Double immunofluorescence revealed colocalization of FUS and p-TDP43, and FUS and PCBP2 (p-TDP43/FUS: 64.3%, PCBP2/FUS: 23.9%). Colocalization of FUS and PCBP1, however, was rare (PCBP1/FUS: 7.6%). In the hippocampi of patients with sporadic ALS, no colocalization was observed between TDP43-positive inclusions and other hnRNPs. This is the first study to show that FUS inclusions colocalize with other hnRNPs, such as TDP43, PCBP2, and PCBP1. These findings suggest that in ALS-FUS, FUS inclusions are the initiators, followed by alterations of multiple other hnRNPs, resulting in impaired RNA metabolism.
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Affiliation(s)
- Hiroyuki Honda
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Motoi Yoshimura
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hajime Arahata
- Division of Neurology, Department of Neurology, Neuro Muscular Center, National Omuta Hospital, Fukuoka, Japan
| | - Kaoru Yagita
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shoko Sadashima
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hideomi Hamasaki
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Masahiro Shijo
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Sachiko Koyama
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hideko Noguchi
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Naokazu Sasagasako
- Division of Neurology, Department of Neurology, Neuro Muscular Center, National Omuta Hospital, Fukuoka, Japan
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Yagita K, Sasagasako N, Koyama S, Noguchi H, Honda H. Amyotrophic lateral sclerosis with TDP-43 abnormalities exhibiting globular glial tau inclusions in frontotemporal lobes and pallido-nigral system. Neuropathology 2023; 43:117-126. [PMID: 36003035 DOI: 10.1111/neup.12862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/28/2022] [Accepted: 08/03/2022] [Indexed: 02/04/2023]
Abstract
Here we present the autopsy case of an 80-year-old woman with a 9-year history of motor neuron disease and atypical Parkinsonism. Her initial symptom was gait disturbance, and she subsequently developed limb weakness and Parkinsonism without response to levodopa. Her motor symptoms progressed to bulbar palsy, and she died of respiratory failure. Postmortem examination revealed characteristic findings of amyotrophic lateral sclerosis (ALS), including motor neuronal loss with astrogliosis, corticospinal tract degeneration, and TAR DNA-binding protein of 43 kDa abnormalities, including nuclear loss and skein-like inclusions. In contrast, severe tau pathological changes were seen in the frontotemporal lobes and pallido-nigral system. Tau pathologies affected not only neuronal components, such as neurofibrillary tangles and neuropil threads, but also glial cells (astrocytes and oligodendrocytes). Some glial tau pathologies exhibited peculiar round accumulations, reminiscent of globular glial inclusions (GGIs) in globular glial tauopathy. This unique autopsy case demonstrates that ALS with TDP-43 could be comorbid with globular glial tau inclusions and indicates that common pathological mechanisms exist among ALS and GGI formation.
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Affiliation(s)
- Kaoru Yagita
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Naokazu Sasagasako
- Department of Neurology, Neuro-Muscular Center, National Omuta Hospital, Omuta, Japan
| | - Sachiko Koyama
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hideko Noguchi
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroyuki Honda
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Han X, Zhan F, Yao Y, Cao L, Liu J, Yao S. Clinical heterogeneity in a family with flail arm syndrome and review of hnRNPA1-related spectrum. Ann Clin Transl Neurol 2022; 9:1910-1917. [PMID: 36314424 PMCID: PMC9735363 DOI: 10.1002/acn3.51682] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 09/24/2022] [Accepted: 10/04/2022] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE Flail arm syndrome (FAS) is one of the atypical subtypes of amyotrophic lateral sclerosis (ALS). Mutations in hnRNPA1 encoding heterogeneous nuclear ribonucleoprotein (hnRNP) A1 are a rare genetic cause of ALS. Herein, marked clinical heterogeneity of FAS in a pedigree with a known hnRNPA1 variant was described to raise early awareness of the ALS variant. Furtherly, a literature review of the hnRNPA1-related spectrum was made to summarize the clinical and genetic characteristics. METHODS Detailed clinical evaluation, muscle pathology, and whole-exome sequencing were performed. The sequence and co-segregation of the mutation among the family members were confirmed by Sanger sequencing. RESULTS The great clinical variability was found in a FAS pedigree. Muscle pathology revealed a cluster distribution of angulated or rounded atrophic fibers, accompanied by significant multi-nucleus aggregation. Immunohistochemical staining showed that mutant hnRNPA1 proteins accumulated in muscle fiber cytoplasm. Exome sequencing identified a documented variant in hnRNPA1 gene c.1018C > T (p.P340S), which co-segregated with disease in the family. Besides, highly phenotypic heterogeneity was also found in other hnRNPA1-related diseases. INTERPRETATION We described a Chinese pedigree with hnRNPA1-related FAS, which showed significant clinical variability among the intrafamilial members. FAS is a relatively milder variant of ALS, due to the highly heterogeneous clinical spectrum, early observation is of paramount importance. In addition, the highly phenotypic heterogeneity and molecular genetic mechanism of the hnRNPA1-related spectrum are still beyond fully understood. Further, the detailed molecular mechanism underlying the clinical diversity is warranted to be explored.
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Affiliation(s)
- Xiaochen Han
- Department of NeurologyThe Sixth Medical Center of PLA General HospitalBeijing100048China
| | - Feixia Zhan
- Department of NeurologyShanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine200233ShanghaiChina
| | - Yuxin Yao
- Department of NeurologyThe Sixth Medical Center of PLA General HospitalBeijing100048China
| | - Li Cao
- Department of NeurologyShanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine200233ShanghaiChina
| | - Jianguo Liu
- Department of NeurologyThe Sixth Medical Center of PLA General HospitalBeijing100048China
| | - Sheng Yao
- Department of NeurologyThe Sixth Medical Center of PLA General HospitalBeijing100048China
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Cappelli S, Spalloni A, Feiguin F, Visani G, Šušnjar U, Brown AL, De Bardi M, Borsellino G, Secrier M, Phatnani H, Romano M, Fratta P, Longone P, Buratti E. NOS1AP is a novel molecular target and critical factor in TDP-43 pathology. Brain Commun 2022; 4:fcac242. [PMID: 36267332 PMCID: PMC9576154 DOI: 10.1093/braincomms/fcac242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 07/05/2022] [Accepted: 09/22/2022] [Indexed: 11/13/2022] Open
Abstract
Many lines of evidence have highlighted the role played by heterogeneous nuclear ribonucleoproteins in amyotrophic lateral sclerosis. In this study, we have aimed to identify transcripts co-regulated by TAR DNA-binding protein 43 kDa and highly conserved heterogeneous nuclear ribonucleoproteins which have been previously shown to regulate TAR DNA-binding protein 43 kDa toxicity (deleted in azoospermia-associated protein 1, heterogeneous nuclear ribonucleoprotein -Q, -D, -K and -U). Using the transcriptome analyses, we have uncovered that Nitric Oxide Synthase 1 Adaptor Protein mRNA is a direct TAR DNA-binding protein 43 kDa target, and in flies, its modulation alone can rescue TAR DNA-binding protein 43 kDa pathology. In primary mouse cortical neurons, we show that TAR DNA-binding protein 43 kDa mediated downregulation of Nitric Oxide Synthase 1 Adaptor Protein expression strongly affects the NMDA-receptor signalling pathway. In human patients, the downregulation of Nitric Oxide Synthase 1 Adaptor Protein mRNA strongly correlates with TAR DNA-binding protein 43 kDa proteinopathy as measured by cryptic Stathmin-2 and Unc-13 homolog A cryptic exon inclusion. Overall, our results demonstrate that Nitric Oxide Synthase 1 Adaptor Protein may represent a novel disease-relevant gene, potentially suitable for the development of new therapeutic strategies.
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Affiliation(s)
- Sara Cappelli
- International Centre for Genetic Engineering and Biotechnology (ICGEB), AREA Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Alida Spalloni
- Molecular Neurobiology, Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, 00143 Rome, Italy
| | - Fabian Feiguin
- Department of Life and Environmental Sciences, University of Cagliari, 09042 Monserrato, Cagliari, Italy
| | - Giulia Visani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), AREA Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Urša Šušnjar
- International Centre for Genetic Engineering and Biotechnology (ICGEB), AREA Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Anna-Leigh Brown
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Marco De Bardi
- Neuroimmunology Unit, Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via Ardeatina 306-354, 00179 Rome, Italy
| | - Giovanna Borsellino
- Neuroimmunology Unit, Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via Ardeatina 306-354, 00179 Rome, Italy
| | - Maria Secrier
- UCL Genetics Institute, Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Hemali Phatnani
- Center for Genomics of Neurodegenerative Disease, New York Genome Center, New York, NY 10013, USA
| | - Maurizio Romano
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, 34127 Trieste, Italy
| | - Pietro Fratta
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
- UCL Genetics Institute, Department of Genetics, Evolution and Environment, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
| | - Patrizia Longone
- Molecular Neurobiology, Experimental Neuroscience, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, 00143 Rome, Italy
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), AREA Science Park, Padriciano 99, 34149 Trieste, Italy
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Heterogeneous nuclear ribonucleoprotein A/B: an emerging group of cancer biomarkers and therapeutic targets. Cell Death Dis 2022; 8:337. [PMID: 35879279 PMCID: PMC9314375 DOI: 10.1038/s41420-022-01129-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/11/2022] [Accepted: 07/13/2022] [Indexed: 11/20/2022]
Abstract
Heterogeneous nuclear ribonucleoprotein A/B (hnRNPA/B) is one of the core members of the RNA binding protein (RBP) hnRNPs family, including four main subtypes, A0, A1, A2/B1 and A3, which share the similar structure and functions. With the advance in understanding the molecular biology of hnRNPA/B, it has been gradually revealed that hnRNPA/B plays a critical role in almost the entire steps of RNA life cycle and its aberrant expression and mutation have important effects on the occurrence and progression of various cancers. This review focuses on the clinical significance of hnRNPA/B in various cancers and systematically summarizes its biological function and molecular mechanisms.
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Nedelsky NB, Taylor JP. Pathological phase transitions in ALS-FTD impair dynamic RNA-protein granules. RNA (NEW YORK, N.Y.) 2022; 28:97-113. [PMID: 34706979 PMCID: PMC8675280 DOI: 10.1261/rna.079001.121] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The genetics of human disease serves as a robust and unbiased source of insight into human biology, both revealing fundamental cellular processes and exposing the vulnerabilities associated with their dysfunction. Over the last decade, the genetics of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) have epitomized this concept, as studies of ALS-FTD-causing mutations have yielded fundamental discoveries regarding the role of biomolecular condensation in organizing cellular contents while implicating disturbances in condensate dynamics as central drivers of neurodegeneration. Here we review this genetic evidence, highlight its intersection with patient pathology, and discuss how studies in model systems have revealed a role for aberrant condensation in neuronal dysfunction and death. We detail how multiple, distinct types of disease-causing mutations promote pathological phase transitions that disturb the dynamics and function of ribonucleoprotein (RNP) granules. Dysfunction of RNP granules causes pleiotropic defects in RNA metabolism and can drive the evolution of these structures to end-stage pathological inclusions characteristic of ALS-FTD. We propose that aberrant phase transitions of these complex condensates in cells provide a parsimonious explanation for the widespread cellular abnormalities observed in ALS as well as certain histopathological features that characterize late-stage disease.
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Affiliation(s)
- Natalia B Nedelsky
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| | - J Paul Taylor
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
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9
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Knock-Down of Heterogeneous Nuclear Ribonucleoprotein A1 Results in Neurite Damage, Altered Stress Granule Biology, and Cellular Toxicity in Differentiated Neuronal Cells. eNeuro 2021; 8:ENEURO.0350-21.2021. [PMID: 34697074 PMCID: PMC8607908 DOI: 10.1523/eneuro.0350-21.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/29/2021] [Accepted: 10/18/2021] [Indexed: 12/13/2022] Open
Abstract
Heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) is an RNA binding protein (RBP) that is localized within neurons and plays crucial roles in RNA metabolism. Its importance in neuronal functioning is underscored from the study of its pathogenic features in many neurodegenerative diseases where neuronal hnRNP A1 is mislocalized from the nucleus to the cytoplasm resulting in loss of hnRNP A1 function. Here, we model hnRNP A1 loss-of-function by siRNA-mediated knock-down in differentiated Neuro-2a cells. Through RNA sequencing (RNA-seq) followed by gene ontology (GO) analyses, we show that hnRNP A1 is involved in important biological processes, including RNA metabolism, neuronal function, neuronal morphology, neuronal viability, and stress granule (SG) formation. We further confirmed several of these roles by showing that hnRNP A1 knock-down results in a reduction of neurite outgrowth, increase in cell cytotoxicity and changes in SG formation. In summary, these findings indicate that hnRNP A1 loss-of-function contributes to neuronal dysfunction and cell death and implicates hnRNP A1 dysfunction in the pathogenesis of neurodegenerative diseases.
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10
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Thibault PA, Ganesan A, Kalyaanamoorthy S, Clarke JPWE, Salapa HE, Levin MC. hnRNP A/B Proteins: An Encyclopedic Assessment of Their Roles in Homeostasis and Disease. BIOLOGY 2021; 10:biology10080712. [PMID: 34439945 PMCID: PMC8389229 DOI: 10.3390/biology10080712] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/16/2021] [Accepted: 07/21/2021] [Indexed: 12/13/2022]
Abstract
The hnRNP A/B family of proteins is canonically central to cellular RNA metabolism, but due to their highly conserved nature, the functional differences between hnRNP A1, A2/B1, A0, and A3 are often overlooked. In this review, we explore and identify the shared and disparate homeostatic and disease-related functions of the hnRNP A/B family proteins, highlighting areas where the proteins have not been clearly differentiated. Herein, we provide a comprehensive assembly of the literature on these proteins. We find that there are critical gaps in our grasp of A/B proteins' alternative splice isoforms, structures, regulation, and tissue and cell-type-specific functions, and propose that future mechanistic research integrating multiple A/B proteins will significantly improve our understanding of how this essential protein family contributes to cell homeostasis and disease.
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Affiliation(s)
- Patricia A. Thibault
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
| | - Aravindhan Ganesan
- ArGan’s Lab, School of Pharmacy, Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
| | - Subha Kalyaanamoorthy
- Department of Chemistry, Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
| | - Joseph-Patrick W. E. Clarke
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Health Sciences, College of Medicine, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Hannah E. Salapa
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
| | - Michael C. Levin
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
- Department of Health Sciences, College of Medicine, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Correspondence:
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11
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Amyotrophic Lateral Sclerosis: Molecular Mechanisms, Biomarkers, and Therapeutic Strategies. Antioxidants (Basel) 2021; 10:antiox10071012. [PMID: 34202494 PMCID: PMC8300638 DOI: 10.3390/antiox10071012] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 06/16/2021] [Accepted: 06/23/2021] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with the progressive loss of motor neurons, leading to a fatal paralysis. According to whether there is a family history of ALS, ALS can be roughly divided into two types: familial and sporadic. Despite decades of research, the pathogenesis of ALS is still unelucidated. To this end, we review the recent progress of ALS pathogenesis, biomarkers, and treatment strategies, mainly discuss the roles of immune disorders, redox imbalance, autophagy dysfunction, and disordered iron homeostasis in the pathogenesis of ALS, and introduce the effects of RNA binding proteins, ALS-related genes, and non-coding RNA as biomarkers on ALS. In addition, we also mention other ALS biomarkers such as serum uric acid (UA), cardiolipin (CL), chitotriosidase (CHIT1), and neurofilament light chain (NFL). Finally, we discuss the drug therapy, gene therapy, immunotherapy, and stem cell-exosomal therapy for ALS, attempting to find new therapeutic targets and strategies. A challenge is to study the various mechanisms of ALS as a syndrome. Biomarkers that have been widely explored are indispensable for the diagnosis, treatment, and prevention of ALS. Moreover, the development of new genes and targets is an urgent task in this field.
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12
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Ryu HG, Jung Y, Lee N, Seo JY, Kim SW, Lee KH, Kim DY, Kim KT. HNRNP A1 Promotes Lung Cancer Cell Proliferation by Modulating VRK1 Translation. Int J Mol Sci 2021; 22:ijms22115506. [PMID: 34071140 PMCID: PMC8197126 DOI: 10.3390/ijms22115506] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 05/14/2021] [Accepted: 05/21/2021] [Indexed: 01/12/2023] Open
Abstract
THeterogeneous nuclear ribonucleoprotein (HNRNP) A1 is the most abundant and ubiquitously expressed member of the HNRNP protein family. In recent years, it has become more evident that HNRNP A1 contributes to the development of neurodegenerative diseases. However, little is known about the underlying role of HNRNP A1 in cancer development. Here, we report that HNRNP A1 expression is significantly increased in lung cancer tissues and is negatively correlated with the overall survival of patients with lung cancer. Additionally, HNRNP A1 positively regulates vaccinia-related kinase 1 (VRK1) translation via binding directly to the 3′ untranslated region (UTR) of VRK1 mRNA, thus increasing cyclin D1 (CCND1) expression by VRK1-mediated phosphorylation of the cAMP response element–binding protein (CREB). Furthermore, HNRNP A1 binding to the cis-acting region of the 3′UTR of VRK1 mRNA contributes to increased lung cancer cell proliferation. Thus, our study unveils a novel role of HNRNP A1 in lung carcinogenesis via post-transcriptional regulation of VRK1 expression and suggests its potential as a therapeutic target for patients with lung cancer.
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Affiliation(s)
- Hye Guk Ryu
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea;
| | - Youngseob Jung
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (Y.J.); (J.-Y.S.); (S.W.K.)
| | - Namgyu Lee
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01065, USA;
| | - Ji-Young Seo
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (Y.J.); (J.-Y.S.); (S.W.K.)
| | - Sung Wook Kim
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (Y.J.); (J.-Y.S.); (S.W.K.)
| | - Kyung-Ha Lee
- Division of Cosmetic Science and Technology, Daegu Haany University, Gyeongsan 38610, Korea;
| | - Do-Yeon Kim
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Korea;
| | - Kyong-Tai Kim
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea;
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (Y.J.); (J.-Y.S.); (S.W.K.)
- Correspondence: ; Tel.: +82-54-279-2297
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13
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Harley J, Clarke BE, Patani R. The Interplay of RNA Binding Proteins, Oxidative Stress and Mitochondrial Dysfunction in ALS. Antioxidants (Basel) 2021; 10:antiox10040552. [PMID: 33918215 PMCID: PMC8066094 DOI: 10.3390/antiox10040552] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/26/2021] [Accepted: 03/31/2021] [Indexed: 12/12/2022] Open
Abstract
RNA binding proteins fulfil a wide number of roles in gene expression. Multiple mechanisms of RNA binding protein dysregulation have been implicated in the pathomechanisms of several neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). Oxidative stress and mitochondrial dysfunction also play important roles in these diseases. In this review, we highlight the mechanistic interplay between RNA binding protein dysregulation, oxidative stress and mitochondrial dysfunction in ALS. We also discuss different potential therapeutic strategies targeting these pathways.
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Affiliation(s)
- Jasmine Harley
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Benjamin E. Clarke
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
- Correspondence: (B.E.C.); (R.P.)
| | - Rickie Patani
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK;
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
- National Hospital for Neurology and Neurosurgery, University College London NHS, London WC1N 3BG, UK
- Correspondence: (B.E.C.); (R.P.)
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14
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Yoshimura M, Honda H, Sasagasako N, Mori S, Hamasaki H, Suzuki SO, Ishii T, Ninomiya T, Kira JI, Iwaki T. PCBP2 Is Downregulated in Degenerating Neurons and Rarely Observed in TDP-43-Positive Inclusions in Sporadic Amyotrophic Lateral Sclerosis. J Neuropathol Exp Neurol 2020; 80:220-228. [PMID: 33313661 DOI: 10.1093/jnen/nlaa148] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Various heterogeneous nuclear ribonucleoproteins (hnRNPs) are deposited in pathological inclusions of amyotrophic lateral sclerosis (ALS) and related diseases, such as frontotemporal lobar degeneration (FTLD). Recently, poly (rC)-binding protein 2 (PCBP2, hnRNP-E2), a member of the hnRNP family, was reported to be colocalized with transactivation-responsive DNA-binding protein 43 kDa (TDP-43)-immunopositive inclusions in cases of FTLD-TDP. Here, we used immunohistochemical methods to investigate PCBP1 and PCBP2 expression in the spinal cords of sporadic ALS patients, with special reference to TDP-43-positive inclusions. Thirty autopsy cases of sporadic ALS were examined by immunohistochemistry using antibodies against PCBP1, PCBP2, sequestosome 1 (p62), and TDP-43. In control subjects without neurological disorders, neurons predominantly expressed PCBP2, rather than PCBP1, in their cytoplasm and nuclei. Anterior horn cells of sporadic ALS patients often had various levels of PCBP2 expression, and motor neurons with skein-like inclusions often had reduced or lost cytoplasmic and nuclear PCBP2 staining. Notably, one case with FTLD-TDP subtype B pathology had marked colocalization of TDP-43 and PCBP2 in the cytoplasmic inclusions and dystrophic neurites of the cerebral cortex, hippocampus, and spinal cord. In conclusion, PCBP2 was reduced in anterior horn cells of sporadic ALS, but its occurrence in TDP-43 inclusions was a rare phenomenon.
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Affiliation(s)
- Motoi Yoshimura
- From the Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroyuki Honda
- From the Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Naokazu Sasagasako
- Department of Neurology, Neuro-Muscular Center, National Omuta Hospital, Omuta, Japan
| | - Shinichiro Mori
- From the Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Neurology, Division of Respirology, Neurology and Rheumatology, Kurume University School of Medicine, Kurume, Japan
| | - Hideomi Hamasaki
- From the Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Satoshi O Suzuki
- From the Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takashi Ishii
- From the Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Biochemistry, Oral Medicine Research Center, Fukuoka Dental College, Fukuoka, Japan
| | - Toshiharu Ninomiya
- Department of Epidemiology and Public Health and Center for Cohort Studies, Graduate School of Medical Science, Kyushu University, Fukuoka, Japan
| | - Jun-Ichi Kira
- Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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15
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The role of hnRNPs in frontotemporal dementia and amyotrophic lateral sclerosis. Acta Neuropathol 2020; 140:599-623. [PMID: 32748079 PMCID: PMC7547044 DOI: 10.1007/s00401-020-02203-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/27/2020] [Accepted: 07/27/2020] [Indexed: 12/12/2022]
Abstract
Dysregulated RNA metabolism is emerging as a crucially important mechanism underpinning the pathogenesis of frontotemporal dementia (FTD) and the clinically, genetically and pathologically overlapping disorder of amyotrophic lateral sclerosis (ALS). Heterogeneous nuclear ribonucleoproteins (hnRNPs) comprise a family of RNA-binding proteins with diverse, multi-functional roles across all aspects of mRNA processing. The role of these proteins in neurodegeneration is far from understood. Here, we review some of the unifying mechanisms by which hnRNPs have been directly or indirectly linked with FTD/ALS pathogenesis, including their incorporation into pathological inclusions and their best-known roles in pre-mRNA splicing regulation. We also discuss the broader functionalities of hnRNPs including their roles in cryptic exon repression, stress granule assembly and in co-ordinating the DNA damage response, which are all emerging pathogenic themes in both diseases. We then present an integrated model that depicts how a broad-ranging network of pathogenic events can arise from declining levels of functional hnRNPs that are inadequately compensated for by autoregulatory means. Finally, we provide a comprehensive overview of the most functionally relevant cellular roles, in the context of FTD/ALS pathogenesis, for hnRNPs A1-U.
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16
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Low YH, Asi Y, Foti SC, Lashley T. Heterogeneous Nuclear Ribonucleoproteins: Implications in Neurological Diseases. Mol Neurobiol 2020; 58:631-646. [PMID: 33000450 PMCID: PMC7843550 DOI: 10.1007/s12035-020-02137-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/17/2020] [Indexed: 12/13/2022]
Abstract
Heterogenous nuclear ribonucleoproteins (hnRNPs) are a complex and functionally diverse family of RNA binding proteins with multifarious roles. They are involved, directly or indirectly, in alternative splicing, transcriptional and translational regulation, stress granule formation, cell cycle regulation, and axonal transport. It is unsurprising, given their heavy involvement in maintaining functional integrity of the cell, that their dysfunction has neurological implications. However, compared to their more established roles in cancer, the evidence of hnRNP implication in neurological diseases is still in its infancy. This review aims to consolidate the evidences for hnRNP involvement in neurological diseases, with a focus on spinal muscular atrophy (SMA), Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), multiple sclerosis (MS), congenital myasthenic syndrome (CMS), and fragile X-associated tremor/ataxia syndrome (FXTAS). Understanding more about hnRNP involvement in neurological diseases can further elucidate the pathomechanisms involved in these diseases and perhaps guide future therapeutic advances.
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Affiliation(s)
- Yi-Hua Low
- The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Disorders, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.,Duke-NUS Medical School, Singapore, Singapore
| | - Yasmine Asi
- The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Disorders, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Sandrine C Foti
- The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Disorders, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK.,Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Tammaryn Lashley
- The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Disorders, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK. .,Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK.
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17
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Salapa HE, Hutchinson C, Popescu BF, Levin MC. Neuronal RNA-binding protein dysfunction in multiple sclerosis cortex. Ann Clin Transl Neurol 2020; 7:1214-1224. [PMID: 32608162 PMCID: PMC7359129 DOI: 10.1002/acn3.51103] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/27/2020] [Accepted: 05/26/2020] [Indexed: 12/12/2022] Open
Abstract
Objective Neurodegeneration is thought to be the primary cause of neurological disability in multiple sclerosis (MS). Dysfunctional RNA‐binding proteins (RBPs) including their mislocalization from nucleus to cytoplasm, stress granule formation, and altered RNA metabolism have been found to underlie neurodegeneration in amyotrophic lateral sclerosis and frontotemporal dementia. Yet, little is known about the role of dysfunctional RBPs in the pathogenesis of neurodegeneration in MS. As a follow‐up to our seminal finding of altered RBP function in a single case of MS, we posited that there would be evidence of RBP dysfunction in cortical neurons in MS. Methods Cortical neurons from 12 MS and six control cases were analyzed by immunohistochemistry for heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) and TAR‐DNA‐binding protein‐43 (TDP‐43). Seven distinct neuronal phenotypes were identified based on the nucleocytoplasmic staining of these RBPs. Statistical analyses were performed by analyzing each phenotype in relation to MS versus controls. Results Analyses revealed a continuum of hnRNP A1 and TDP‐43 nucleocytoplasmic staining was found in cortical neurons, from neurons with entirely nuclear staining with little cytoplasmic staining in contrast to those with complete nuclear depletion of RBPs concurrent with robust cytoplasmic staining. The neuronal phenotypes that showed the most nucleocytoplasmic mislocalization of hnRNP A1 and TDP‐43 statistically distinguished MS from control cases (P < 0.01, P < 0.001, respectively). Interpretation The discovery of hnRNP A1 and TDP‐43 nucleocytoplasmic mislocalization in neurons in MS brain demonstrate that dysfunctional RBPs may play a role in neurodegeneration in MS, as they do in other neurological diseases.
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Affiliation(s)
- Hannah E Salapa
- Department of Anatomy, Physiology and Pharmacology & Cameco MS Neuroscience Research Center, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada.,Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK, Canada
| | - Catherine Hutchinson
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK, Canada.,Neurology Division, Department of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Bogdan F Popescu
- Department of Anatomy, Physiology and Pharmacology & Cameco MS Neuroscience Research Center, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Michael C Levin
- Department of Anatomy, Physiology and Pharmacology & Cameco MS Neuroscience Research Center, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada.,Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK, Canada.,Neurology Division, Department of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
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18
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A Systematic Review of Genotype-Phenotype Correlation across Cohorts Having Causal Mutations of Different Genes in ALS. J Pers Med 2020; 10:jpm10030058. [PMID: 32610599 PMCID: PMC7564886 DOI: 10.3390/jpm10030058] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis is a rare and fatal neurodegenerative disease characterised by progressive deterioration of upper and lower motor neurons that eventually culminates in severe muscle atrophy, respiratory failure and death. There is a concerning lack of understanding regarding the mechanisms that lead to the onset of ALS and as a result there are no reliable biomarkers that aid in the early detection of the disease nor is there an effective treatment. This review first considers the clinical phenotypes associated with ALS, and discusses the broad categorisation of ALS and ALS-mimic diseases into upper and lower motor neuron diseases, before focusing on the genetic aetiology of ALS and considering the potential relationship of mutations of different genes to variations in phenotype. For this purpose, a systematic review is conducted collating data from 107 original published clinical studies on monogenic forms of the disease, surveying the age and site of onset, disease duration and motor neuron involvement. The collected data highlight the complexity of the disease's genotype-phenotype relationship, and thus the need for a nuanced approach to the development of clinical assays and therapeutics.
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19
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Picchiarelli G, Dupuis L. Role of RNA Binding Proteins with prion-like domains in muscle and neuromuscular diseases. Cell Stress 2020; 4:76-91. [PMID: 32292882 PMCID: PMC7146060 DOI: 10.15698/cst2020.04.217] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A number of neuromuscular and muscular diseases, including amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA) and several myopathies, are associated to mutations in related RNA-binding proteins (RBPs), including TDP-43, FUS, MATR3 or hnRNPA1/B2. These proteins harbor similar modular primary sequence with RNA binding motifs and low complexity domains, that enables them to phase separate and create liquid microdomains. These RBPs have been shown to critically regulate multiple events of RNA lifecycle, including transcriptional events, splicing and RNA trafficking and sequestration. Here, we review the roles of these disease-related RBPs in muscle and motor neurons, and how their dysfunction in these cell types might contribute to disease.
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Affiliation(s)
- Gina Picchiarelli
- Université de Strasbourg, INSERM, Mécanismes Centraux et Périphériques de la Neurodégénérescence, UMR_S 1118, Strasbourg, France
| | - Luc Dupuis
- Université de Strasbourg, INSERM, Mécanismes Centraux et Périphériques de la Neurodégénérescence, UMR_S 1118, Strasbourg, France
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20
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St Martin JL, Wang L, Kaprielian Z. Toxicity in ALS: TDP-43 modifiers and C9orf72. Neurosci Lett 2019; 716:134621. [PMID: 31726180 DOI: 10.1016/j.neulet.2019.134621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 10/24/2019] [Accepted: 11/07/2019] [Indexed: 12/13/2022]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a devastating and fatal neurodegenerative disease affecting approximately 30,000 individuals in the United States. The average age of onset is 55 years and progression of the disease is rapid with most patients dying of respiratory failure within 3-5 years. Currently available therapeutics have modest effects on patient survival, underscoring the immediate need for more effective medicines. Recent technological advances in next generation sequencing have led to a substantial uptick in the discovery of genes linked to ALS. Since 90 % of ALS cases are sporadic, risk genes identified in familial cases provide invaluable insights into the molecular pathogenesis of the disease. Most notably, TDP-43-expressing neuronal inclusions and C9orf72 mutations have emerged as the key pathological and genetic hallmarks, respectively, of ALS. In this review, we will discuss recent advances in modifiers of TDP-43 toxicity, with an emphasis on Ataxin-2, one of the most well-characterized TDP-43 modifiers. An understanding of Ataxin-2 function and related biological pathways could provide a framework for the discovery of other novel modifiers of TDP-43. We will also describe the pathogenic mechanisms underlying C9orf72 toxicity and how these impact the disease process. Finally, we will explore emerging therapeutic strategies for dampening TDP-43 and C9orf72 toxicity and, ultimately, slowing or halting the progression of ALS.
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Affiliation(s)
| | - Lina Wang
- Amgen, Neuroscience Discovery, Cambridge, MA, United States
| | - Zaven Kaprielian
- Dementia Discovery Foundation US Discovery, Boston, United States.
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21
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Mori S, Honda H, Ishii T, Yoshimura M, Sasagasako N, Suzuki SO, Taniwaki T, Iwaki T. Expanded polyglutamine impairs normal nuclear distribution of fused in sarcoma and poly (rC)‐binding protein 1 in Huntington's disease. Neuropathology 2019; 39:358-367. [DOI: 10.1111/neup.12600] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 07/25/2019] [Accepted: 08/08/2019] [Indexed: 12/14/2022]
Affiliation(s)
- Shinichiro Mori
- Department of NeuropathologyGraduate School of Medical Sciences, Kyushu University Fukuoka Japan
- Department of Neurology, Division of Respirology, Neurology and Rheumatology, Department of MedicineKurume University School of Medicine Kurume Japan
| | - Hiroyuki Honda
- Department of NeuropathologyGraduate School of Medical Sciences, Kyushu University Fukuoka Japan
| | - Takashi Ishii
- Department of BiochemistryFukuoka Dental College Fukuoka Japan
| | - Motoi Yoshimura
- Department of NeuropathologyGraduate School of Medical Sciences, Kyushu University Fukuoka Japan
| | - Naokazu Sasagasako
- Department of NeurologyNeuro‐Muscular Center, National Omuta Hospital Omuta Japan
| | - Satoshi O. Suzuki
- Department of NeuropathologyGraduate School of Medical Sciences, Kyushu University Fukuoka Japan
| | - Takayuki Taniwaki
- Department of Neurology, Division of Respirology, Neurology and Rheumatology, Department of MedicineKurume University School of Medicine Kurume Japan
| | - Toru Iwaki
- Department of NeuropathologyGraduate School of Medical Sciences, Kyushu University Fukuoka Japan
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22
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Bradley RA, Shireman J, McFalls C, Choi J, Canfield SG, Dong Y, Liu K, Lisota B, Jones JR, Petersen A, Bhattacharyya A, Palecek SP, Shusta EV, Kendziorski C, Zhang SC. Regionally specified human pluripotent stem cell-derived astrocytes exhibit different molecular signatures and functional properties. Development 2019; 146:dev.170910. [PMID: 31189664 DOI: 10.1242/dev.170910] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 06/03/2019] [Indexed: 01/10/2023]
Abstract
Astrocytes display diverse morphologies in different regions of the central nervous system. Whether astrocyte diversity is attributable to developmental processes and bears functional consequences, especially in humans, is unknown. RNA-seq of human pluripotent stem cell-derived regional astrocytes revealed distinct transcript profiles, suggesting differential functional properties. This was confirmed by differential calcium signaling as well as effects on neurite growth and blood-brain barrier formation. Distinct transcriptional profiles and functional properties of human astrocytes generated from regionally specified neural progenitors under the same conditions strongly implicate the developmental impact on astrocyte diversity. These findings provide a rationale for renewed examination of regional astrocytes and their role in the pathogenesis of psychiatric and neurological disorders.
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Affiliation(s)
- Robert A Bradley
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA.,Cellular and Molecular Biology Program, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Jack Shireman
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Caya McFalls
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Jeea Choi
- Department of Statistics, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Scott G Canfield
- Department of Chemical and Biological Engineering, University of Wisconsin - Madison, Madison, WI 53705, USA.,Department of Cellular and Integrative Physiology, School of Medicine, Indiana University - Terre Haute, IN 47885, USA
| | - Yi Dong
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Katie Liu
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Brianne Lisota
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Jeffery R Jones
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Andrew Petersen
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Anita Bhattacharyya
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Sean P Palecek
- Department of Chemical and Biological Engineering, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Eric V Shusta
- Department of Chemical and Biological Engineering, University of Wisconsin - Madison, Madison, WI 53705, USA
| | - Christina Kendziorski
- Department of Biostatistics and Medical Informatics, University of Wisconsin - Madison, Madison, WI 53792, USA
| | - Su-Chun Zhang
- Department of Neuroscience, Waisman Center, University of Wisconsin - Madison, Madison, WI 53705, USA .,Cellular and Molecular Biology Program, University of Wisconsin - Madison, Madison, WI 53705, USA.,Department of Neuroscience, Department of Neurology, School of Medicine and Public Health, University of Wisconsin - Madison, Madison, WI 53705, USA.,Program in Neuroscience & Behavioral Disorders, Duke-NUS Medical School, Singapore 169857
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23
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Fratta P, Isaacs AM. The snowball effect of RNA binding protein dysfunction in amyotrophic lateral sclerosis. Brain 2019; 141:1236-1238. [PMID: 29701791 PMCID: PMC5917769 DOI: 10.1093/brain/awy091] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- Pietro Fratta
- UCL Institute of Neurology, and MRC Centre for Neuromuscular Disease, Queen Square, London, WC1N 3BG, UK
| | - Adrian M Isaacs
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square London, WC1N 3BG, UK.,UK Dementia Research Institute at UCL, UCL Institute of Neurology, Queen Square London, WC1N 3BG, UK
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24
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Zhao M, Kim JR, van Bruggen R, Park J. RNA-Binding Proteins in Amyotrophic Lateral Sclerosis. Mol Cells 2018; 41:818-829. [PMID: 30157547 PMCID: PMC6182225 DOI: 10.14348/molcells.2018.0243] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 07/23/2018] [Accepted: 08/10/2018] [Indexed: 12/11/2022] Open
Abstract
Significant research efforts are ongoing to elucidate the complex molecular mechanisms underlying amyotrophic lateral sclerosis (ALS), which may in turn pinpoint potential therapeutic targets for treatment. The ALS research field has evolved with recent discoveries of numerous genetic mutations in ALS patients, many of which are in genes encoding RNA binding proteins (RBPs), including TDP-43, FUS, ATXN2, TAF15, EWSR1, hnRNPA1, hnRNPA2/B1, MATR3 and TIA1. Accumulating evidence from studies on these ALS-linked RBPs suggests that dysregulation of RNA metabolism, cytoplasmic mislocalization of RBPs, dysfunction in stress granule dynamics of RBPs and increased propensity of mutant RBPs to aggregate may lead to ALS pathogenesis. Here, we review current knowledge of the biological function of these RBPs and the contributions of ALS-linked mutations to disease pathogenesis.
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Affiliation(s)
- Melody Zhao
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
- Department of Molecular Genetics, University of Toronto, Toronto,
Canada
| | - Jihye Rachel Kim
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
- Department of Molecular Genetics, University of Toronto, Toronto,
Canada
| | - Rebekah van Bruggen
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
| | - Jeehye Park
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
- Department of Molecular Genetics, University of Toronto, Toronto,
Canada
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25
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Maeda N, Honda H, Suzuki SO, Fujii N, Kira JI, Iwaki T. Mitochondrial dysfunction and altered ribostasis in hippocampal neurons with cytoplasmic inclusions of multiple system atrophy. Neuropathology 2018; 38:361-371. [PMID: 29961958 DOI: 10.1111/neup.12482] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 04/30/2018] [Accepted: 05/01/2018] [Indexed: 11/30/2022]
Abstract
Multiple system atrophy (MSA) is a sporadic adult-onset neurodegenerative disease. It has recently been shown that patients with MSA accompanied by cognitive decline display numerous neuronal cytoplasmic inclusions (NCIs) in the limbic neurons. We examined potential mechanisms underlying the formation of these NCIs by determining of mitochondrial function and statuses of RNA processing by analyzing 12 pathologically confirmed cases of MSA. Among them, four had cognitive impairment Semiquantitative evaluation using immunohistochemistry analyses revealed a significantly greater NCI burden in the hippocampal cornu ammonis 1 (CA1) subfield, subiculum, and amygdala in the cases with cognitive impairments compared with those without cognitive impairment. Immunofluorescent staining revealed that limbic neurons with NCIs often accelerated production of reactive oxygen species (ROS) and degraded mitochondrial quality control. Immunofluorescent staining also revealed that neurons with these NCIs translocated heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) from the nucleus and aggregated abnormally at the perinuclear rim. Since the NCIs in the hippocampal neurons of MSA with cognitive impairments were more numerous, the neuronal mitochondrial dysfunction and altered ribostasis observed in NCI formation may be involved in the hippocampal degeneration of MSA.
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Affiliation(s)
- Norihisa Maeda
- Department of Neuropathology, Kyushu University, Fukuoka, Japan
- Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroyuki Honda
- Department of Neuropathology, Kyushu University, Fukuoka, Japan
| | | | - Naoki Fujii
- Department of Neurology, Neuro-Muscular Center, National Omuta Hospital, Fukuoka, Japan
| | - Jun-Ichi Kira
- Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Toru Iwaki
- Department of Neuropathology, Kyushu University, Fukuoka, Japan
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26
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Fifita JA, Zhang KY, Galper J, Williams KL, McCann EP, Hogan AL, Saunders N, Bauer D, Tarr IS, Pamphlett R, Nicholson GA, Rowe D, Yang S, Blair IP. Genetic and Pathological Assessment of hnRNPA1, hnRNPA2/B1, and hnRNPA3 in Familial and Sporadic Amyotrophic Lateral Sclerosis. NEURODEGENER DIS 2017; 17:304-312. [DOI: 10.1159/000481258] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 08/29/2017] [Indexed: 12/27/2022] Open
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Appocher C, Mohagheghi F, Cappelli S, Stuani C, Romano M, Feiguin F, Buratti E. Major hnRNP proteins act as general TDP-43 functional modifiers both in Drosophila and human neuronal cells. Nucleic Acids Res 2017; 45:8026-8045. [PMID: 28575377 PMCID: PMC5570092 DOI: 10.1093/nar/gkx477] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 05/16/2017] [Indexed: 12/13/2022] Open
Abstract
Nuclear factor TDP-43 is known to play an important role in several neurodegenerative pathologies. In general, TDP-43 is an abundant protein within the eukaryotic nucleus that binds to many coding and non-coding RNAs and influence their processing. Using Drosophila, we have performed a functional screening to establish the ability of major hnRNP proteins to affect TDP-43 overexpression/depletion phenotypes. Interestingly, we observed that lowering hnRNP and TDP-43 expression has a generally harmful effect on flies locomotor abilities. In parallel, our study has also identified a distinct set of hnRNPs that is capable of powerfully rescuing TDP-43 toxicity in the fly eye (Hrb27c, CG42458, Glo and Syp). Most importantly, removing the human orthologs of Hrb27c (DAZAP1) in human neuronal cell lines can correct several pre-mRNA splicing events altered by TDP-43 depletion. Moreover, using RNA sequencing analysis we show that DAZAP1 and TDP-43 can co-regulate an extensive number of biological processes and molecular functions potentially important for the neuron/motor neuron pathophysiology. Our results suggest that changes in hnRNP expression levels can significantly modulate TDP-43 functions and affect pathological outcomes.
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Affiliation(s)
- Chiara Appocher
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Fatemeh Mohagheghi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Sara Cappelli
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Maurizio Romano
- Department of Life Sciences, University of Trieste, Via A. Valerio 28, 34127 Trieste, Italy
| | - Fabian Feiguin
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
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Kapeli K, Martinez FJ, Yeo GW. Genetic mutations in RNA-binding proteins and their roles in ALS. Hum Genet 2017; 136:1193-1214. [PMID: 28762175 PMCID: PMC5602095 DOI: 10.1007/s00439-017-1830-7] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Accepted: 07/17/2017] [Indexed: 12/11/2022]
Abstract
Mutations in genes that encode RNA-binding proteins (RBPs) have emerged as critical determinants of neurological diseases, especially motor neuron disorders such as amyotrophic lateral sclerosis (ALS). RBPs are involved in all aspects of RNA processing, controlling the life cycle of RNAs from synthesis to degradation. Hallmark features of RBPs in neuron dysfunction include misregulation of RNA processing, mislocalization of RBPs to the cytoplasm, and abnormal aggregation of RBPs. Much progress has been made in understanding how ALS-associated mutations in RBPs drive pathogenesis. Here, we focus on several key RBPs involved in ALS—TDP-43, HNRNP A2/B1, HNRNP A1, FUS, EWSR1, and TAF15—and review our current understanding of how mutations in these proteins cause disease.
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Affiliation(s)
- Katannya Kapeli
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Fernando J Martinez
- Department of Cellular and Molecular Medicine, Stem Cell Program and Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Gene W Yeo
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore.
- Department of Cellular and Molecular Medicine, Stem Cell Program and Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA, 92093, USA.
- Molecular Engineering Laboratory, A*STAR, Singapore, 138673, Singapore.
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29
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Moujalled D, Grubman A, Acevedo K, Yang S, Ke YD, Moujalled DM, Duncan C, Caragounis A, Perera ND, Turner BJ, Prudencio M, Petrucelli L, Blair I, Ittner LM, Crouch PJ, Liddell JR, White AR. TDP-43 mutations causing amyotrophic lateral sclerosis are associated with altered expression of RNA-binding protein hnRNP K and affect the Nrf2 antioxidant pathway. Hum Mol Genet 2017; 26:1732-1746. [PMID: 28334913 DOI: 10.1093/hmg/ddx093] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 03/07/2017] [Indexed: 12/12/2022] Open
Abstract
TAR DNA binding protein 43 (TDP-43) is a major disease-associated protein involved in the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). Our previous studies found a direct association between TDP-43 and heterogeneous nuclear ribonucleoprotein K (hnRNP K). In this study, utilizing ALS patient fibroblasts harboring a TDP-43M337V mutation and NSC-34 motor neuronal cell line expressing TDP-43Q331K mutation, we show that hnRNP K expression is impaired in urea soluble extracts from mutant TDP-43 cell models. This was confirmed in vivo using TDP-43Q331K and inducible TDP-43A315T murine ALS models. We further investigated the potential pathological effects of mutant TDP-43-mediated changes to hnRNP K metabolism by RNA binding immunoprecipitation analysis. hnRNP K protein was bound to antioxidant NFE2L2 transcripts encoding Nrf2 antioxidant transcription factor, with greater enrichment in TDP-43M337V patient fibroblasts compared to healthy controls. Subsequent gene expression profiling revealed an increase in downstream antioxidant transcript expression of Nrf2 signaling in the spinal cord of TDP-43Q331K mice compared to control counterparts, yet the corresponding protein expression was not up-regulated in transgenic mice. Despite the elevated expression of antioxidant transcripts, we observed impaired levels of glutathione (downstream Nrf2 antioxidant) in TDP-43M337V patient fibroblasts and astrocyte cultures from TDP-43Q331K mice, indicative of elevated oxidative stress and failure of some upregulated antioxidant genes to be translated into protein. Our findings indicate that further exploration of the interplay between hnRNP K (or other hnRNPs) and Nrf2-mediated antioxidant signaling is warranted and may be an important driver for motor neuron degeneration in ALS.
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Affiliation(s)
- Diane Moujalled
- Department of Pathology, The University of Melbourne, Victoria 3010, Australia
| | - Alexandra Grubman
- Department of Pathology, The University of Melbourne, Victoria 3010, Australia
| | - Karla Acevedo
- Department of Pathology, The University of Melbourne, Victoria 3010, Australia
| | - Shu Yang
- The Australian School of Advanced Medicine, Macquarie University, NSW 2109, Australia
| | - Yazi D Ke
- Dementia Research Unit, Department of Anatomy, Faculty of Medicine, School of Medical Sciences, UNSW Australia, Sydney, NSW 2052, Australia
| | - Donia M Moujalled
- Australian Centre for Blood Diseases (ACBD), The Alfred Centre, Victoria 3004, Australia
| | - Clare Duncan
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3010, Australia
| | | | - Nirma D Perera
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3010, Australia
| | - Bradley J Turner
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3010, Australia
| | | | | | - Ian Blair
- The Australian School of Advanced Medicine, Macquarie University, NSW 2109, Australia
| | - Lars M Ittner
- Dementia Research Unit, Department of Anatomy, Faculty of Medicine, School of Medical Sciences, UNSW Australia, Sydney, NSW 2052, Australia
| | - Peter J Crouch
- Department of Pathology, The University of Melbourne, Victoria 3010, Australia
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3010, Australia
| | - Jeffrey R Liddell
- Department of Pathology, The University of Melbourne, Victoria 3010, Australia
| | - Anthony R White
- Department of Pathology, The University of Melbourne, Victoria 3010, Australia
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria 3010, Australia
- Berghofer Medical Research Institute, Herston, Queensland 4006, Australia
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MicroRNA Metabolism and Dysregulation in Amyotrophic Lateral Sclerosis. Mol Neurobiol 2017; 55:2617-2630. [PMID: 28421535 DOI: 10.1007/s12035-017-0537-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 04/07/2017] [Indexed: 12/12/2022]
Abstract
MicroRNAs (miRNAs) are a subset of endogenous, small, non-coding RNA molecules involved in the post-transcriptional regulation of eukaryotic gene expression. Dysregulation in miRNA-related pathways in the central nervous system (CNS) is associated with severe neuronal injury and cell death, which can lead to the development of neurodegenerative disorders, such as amyotrophic lateral sclerosis (ALS). ALS is a fatal adult onset disease characterized by the selective loss of upper and lower motor neurons. While the pathogenesis of ALS is still largely unknown, familial ALS forms linked to TAR DNA-binding protein 43 (TDP-43) and fused in sarcoma (FUS) gene mutations, as well as sporadic forms, display changes in several steps of RNA metabolism, including miRNA processing. Here, we review the current knowledge about miRNA metabolism and biological functions and their crucial role in ALS pathogenesis with an in-depth analysis on different pathways. A more precise understanding of miRNA involvement in ALS could be useful not only to elucidate their role in the disease etiopathogenesis but also to investigate their potential as disease biomarkers and novel therapeutic targets.
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31
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Suzuki H, Matsuoka M. hnRNPA1 autoregulates its own mRNA expression to remain non-cytotoxic. Mol Cell Biochem 2016; 427:123-131. [PMID: 28000042 DOI: 10.1007/s11010-016-2904-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 12/03/2016] [Indexed: 01/03/2023]
Abstract
Heterogeneous nuclear ribonucleoprotein (hnRNP)A1, a member of the hnRNP family, is involved in a variety of RNA metabolisms. The hnRNPA1 expression is altered in some human diseases and mutations of the hnRNPA1 gene cause amyotrophic lateral sclerosis and multisystem proteinopathy. It has been therefore assumed that the dysregulation of hnRNPA1 is linked to the pathogenesis of the diseases. However, the mechanism underlying the regulation of the hnRNPA1 expression remains unknown. In this study, using cell-based models, we have found that hnRNPA1 negatively regulates its own mRNA expression by inhibiting the intron10 splicing of hnRNPA1 pre-mRNA. This mechanism likely serves as an autoregulation of the hnRNPA1 expression. We have also found that a low-grade excess of hnRNPA1 expression causes cytotoxicity by activating the mitochondrial apoptosis pathway. Collectively, these data suggest that the level of hnRNPA1 is strictly controlled to be within a certain range by the mRNA autoregulation in the physiological condition so that the cytotoxicity-causative alteration of hnRNPA1 expression does not take place.
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Affiliation(s)
- Hiroaki Suzuki
- Department of Pharmacology, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-Ku, Tokyo, 160-8402, Japan
| | - Masaaki Matsuoka
- Department of Pharmacology, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-Ku, Tokyo, 160-8402, Japan. .,Department of Dermatological Neuroscience, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-Ku, Tokyo, 160-8402, Japan.
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32
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Guerrero EN, Wang H, Mitra J, Hegde PM, Stowell SE, Liachko NF, Kraemer BC, Garruto RM, Rao KS, Hegde ML. TDP-43/FUS in motor neuron disease: Complexity and challenges. Prog Neurobiol 2016; 145-146:78-97. [PMID: 27693252 PMCID: PMC5101148 DOI: 10.1016/j.pneurobio.2016.09.004] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Revised: 08/19/2016] [Accepted: 09/20/2016] [Indexed: 01/05/2023]
Abstract
Amyotrophic lateral sclerosis (ALS), a common motor neuron disease affecting two per 100,000 people worldwide, encompasses at least five distinct pathological subtypes, including, ALS-SOD1, ALS-C9orf72, ALS-TDP-43, ALS-FUS and Guam-ALS. The etiology of a major subset of ALS involves toxicity of the TAR DNA-binding protein-43 (TDP-43). A second RNA/DNA binding protein, fused in sarcoma/translocated in liposarcoma (FUS/TLS) has been subsequently associated with about 1% of ALS patients. While mutations in TDP-43 and FUS have been linked to ALS, the key contributing molecular mechanism(s) leading to cell death are still unclear. One unique feature of TDP-43 and FUS pathogenesis in ALS is their nuclear clearance and simultaneous cytoplasmic aggregation in affected motor neurons. Since the discoveries in the last decade implicating TDP-43 and FUS toxicity in ALS, a majority of studies have focused on their cytoplasmic aggregation and disruption of their RNA-binding functions. However, TDP-43 and FUS also bind to DNA, although the significance of their DNA binding in disease-affected neurons has been less investigated. A recent observation of accumulated genomic damage in TDP-43 and FUS-linked ALS and association of FUS with neuronal DNA damage repair pathways indicate a possible role of deregulated DNA binding function of TDP-43 and FUS in ALS. In this review, we discuss the different ALS disease subtypes, crosstalk of etiopathologies in disease progression, available animal models and their limitations, and recent advances in understanding the specific involvement of RNA/DNA binding proteins, TDP-43 and FUS, in motor neuron diseases.
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Affiliation(s)
- Erika N. Guerrero
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, USA
- Centre for Neuroscience, Institute for Scientific Research and Technology Services (INDICASAT-AIP), City of Knowledge, Panama
- Department of Biotechnology, Acharya Nagarjuna University, Guntur, India
| | - Haibo Wang
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, USA
| | - Joy Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, USA
| | - Pavana M. Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, USA
| | - Sara E. Stowell
- Department of Anthropology, Binghamton University, State University of New York, Binghamton, New York
| | - Nicole F Liachko
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, 98108, USA
| | - Brian C. Kraemer
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, 98108, USA
| | - Ralph M. Garruto
- Department of Anthropology, Binghamton University, State University of New York, Binghamton, New York
- Department of Biological Sciences, Binghamton University, State University of New York, Binghamton, New York
| | - K. S. Rao
- Centre for Neuroscience, Institute for Scientific Research and Technology Services (INDICASAT-AIP), City of Knowledge, Panama
- Department of Biotechnology, Acharya Nagarjuna University, Guntur, India
| | - Muralidhar L. Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, USA
- Houston Methodist Neurological Institute, Houston, Texas 77030 USA
- Weill Medical College of Cornell University, New York
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33
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TDP-43 aggregation mirrors TDP-43 knockdown, affecting the expression levels of a common set of proteins. Sci Rep 2016; 6:33996. [PMID: 27665936 PMCID: PMC5036055 DOI: 10.1038/srep33996] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 09/06/2016] [Indexed: 12/12/2022] Open
Abstract
TDP-43 protein plays an important role in regulating transcriptional repression, RNA metabolism, and splicing. Typically it shuttles between the nucleus and the cytoplasm to perform its functions, while abnormal cytoplasmic aggregation of TDP-43 has been associated with neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). For the purpose of this study we selected a set of proteins that were misregulated following silencing of TDP-43 and analysed their expression in a TDP-43-aggregation model cell line HEK293 Flp-in Flag-TDP-43-12x-Q/N F4L. Following TDP-43 sequestration in insoluble aggregates, we observed higher nuclear levels of EIF4A3, and POLDIP3β, whereas nuclear levels of DNMT3A, HNRNPA3, PABPC1 and POLDIP3α dropped, and cytoplasmic levels of RANBP1 dropped. In addition, immunofluorescence signal intensity quantifications showed increased nuclear expression of HNRNPL and YARS, and downregulation of cytoplasmic DPCD. Furthermore, cytoplasmic levels of predominantly nuclear protein ALYREF increased. In conclusion, by identifying a common set of proteins that are differentially expressed in a similar manner in these two different conditions, we show that TDP-43 aggregation has a comparable effect to TDP-43 knockdown.
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Abstract
The 3′ untranslated regions (3′UTRs) of mammalian mRNAs direct an extensive range of alternative post-transcriptional outcomes, including regulation of mRNA decay and translation, contributing significantly to overall gene regulation. However, our knowledge of the underlying sequences and mechanisms is incomplete. We identified a novel 3′UTR sequence motif in mammals that targets mRNAs for transcript degradation. The motif is found in hundreds of mRNAs and is enriched in transcripts encoding regulatory proteins, such as transcription and signaling factors. Degradation of mRNAs containing the motif is mediated by the CCR4-NOT deadenylation complex. We identified hnRNPs A1 and A2/B1 as trans factors that directly bind to the motif, indicating a novel role for these proteins in deadenylation. Interestingly, a genome-wide analysis of the impact of this new regulatory pathway showed that the most active motifs are located within the 5′ and 3′-terminal portions of 3′UTRs, whereas elements in the center tend to be inactive. The highly position-specific function of the motif adds a new layer of regulation to gene expression mediated by 3′UTRs.
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Affiliation(s)
- Rene Geissler
- a Department of Molecular Biology and Genetics , Cornell University , Ithaca , NY , USA
| | - Andrew Grimson
- a Department of Molecular Biology and Genetics , Cornell University , Ithaca , NY , USA
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Boeynaems S, Bogaert E, Van Damme P, Van Den Bosch L. Inside out: the role of nucleocytoplasmic transport in ALS and FTLD. Acta Neuropathol 2016; 132:159-173. [PMID: 27271576 PMCID: PMC4947127 DOI: 10.1007/s00401-016-1586-5] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 05/27/2016] [Accepted: 05/28/2016] [Indexed: 12/11/2022]
Abstract
Neurodegenerative diseases are characterized by the presence of protein inclusions with a different protein content depending on the type of disease. Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are no exceptions to this common theme. In most ALS and FTLD cases, the predominant pathological species are RNA-binding proteins. Interestingly, these proteins are both depleted from their normal nuclear localization and aggregated in the cytoplasm. This key pathological feature has suggested a potential dual mechanism with both nuclear loss of function and cytoplasmic gain of function being at play. Yet, why and how this pathological cascade is initiated in most patients, and especially sporadic cases, is currently unresolved. Recent breakthroughs in C9orf72 ALS/FTLD disease models point at a pivotal role for the nuclear transport system in toxicity. To address whether defects in nuclear transport are indeed implicated in the disease, we reviewed two decades of ALS/FTLD literature and combined this with bioinformatic analyses. We find that both RNA-binding proteins and nuclear transport factors are key players in ALS/FTLD pathology. Moreover, our analyses suggest that disturbances in nucleocytoplasmic transport play a crucial initiating role in the disease, by bridging both nuclear loss and cytoplasmic gain of functions. These findings highlight this process as a novel and promising therapeutic target for ALS and FTLD.
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Affiliation(s)
- Steven Boeynaems
- />Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven-University of Leuven, 3000 Leuven, Belgium
- />Laboratory of Neurobiology, Vesalius Research Center, VIB, Campus Gasthuisberg O&N4, PB912, Herestraat 49, 3000 Leuven, Belgium
| | - Elke Bogaert
- />Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven-University of Leuven, 3000 Leuven, Belgium
- />Laboratory of Neurobiology, Vesalius Research Center, VIB, Campus Gasthuisberg O&N4, PB912, Herestraat 49, 3000 Leuven, Belgium
| | - Philip Van Damme
- />Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven-University of Leuven, 3000 Leuven, Belgium
- />Laboratory of Neurobiology, Vesalius Research Center, VIB, Campus Gasthuisberg O&N4, PB912, Herestraat 49, 3000 Leuven, Belgium
| | - Ludo Van Den Bosch
- />Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven-University of Leuven, 3000 Leuven, Belgium
- />Laboratory of Neurobiology, Vesalius Research Center, VIB, Campus Gasthuisberg O&N4, PB912, Herestraat 49, 3000 Leuven, Belgium
- />Department of Neurology, University Hospitals Leuven, 3000 Leuven, Belgium
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Krebs BB, De Mesquita JF. Amyotrophic Lateral Sclerosis Type 20 - In Silico Analysis and Molecular Dynamics Simulation of hnRNPA1. PLoS One 2016; 11:e0158939. [PMID: 27414033 PMCID: PMC4945010 DOI: 10.1371/journal.pone.0158939] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 06/24/2016] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease that affects the upper and lower motor neurons. 5-10% of cases are genetically inherited, including ALS type 20, which is caused by mutations in the hnRNPA1 gene. The goals of this work are to analyze the effects of non-synonymous single nucleotide polymorphisms (nsSNPs) on hnRNPA1 protein function, to model the complete tridimensional structure of the protein using computational methods and to assess structural and functional differences between the wild type and its variants through Molecular Dynamics simulations. nsSNP, PhD-SNP, Polyphen2, SIFT, SNAP, SNPs&GO, SNPeffect and PROVEAN were used to predict the functional effects of nsSNPs. Ab initio modeling of hnRNPA1 was made using Rosetta and refined using KoBaMIN. The structure was validated by PROCHECK, Rampage, ERRAT, Verify3D, ProSA and Qmean. TM-align was used for the structural alignment. FoldIndex, DICHOT, ELM, D2P2, Disopred and DisEMBL were used to predict disordered regions within the protein. Amino acid conservation analysis was assessed by Consurf, and the molecular dynamics simulations were performed using GROMACS. Mutations D314V and D314N were predicted to increase amyloid propensity, and predicted as deleterious by at least three algorithms, while mutation N73S was predicted as neutral by all the algorithms. D314N and D314V occur in a highly conserved amino acid. The Molecular Dynamics results indicate that all mutations increase protein stability when compared to the wild type. Mutants D314N and N319S showed higher overall dimensions and accessible surface when compared to the wild type. The flexibility level of the C-terminal residues of hnRNPA1 is affected by all mutations, which may affect protein function, especially regarding the protein ability to interact with other proteins.
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Affiliation(s)
- Bruna Baumgarten Krebs
- Laboratory of Bioinformatics and Computational Biology, Department of Genetics and Molecular Biology, Federal University of Rio de Janeiro State (UNIRIO), Rio de Janeiro, Brazil
| | - Joelma Freire De Mesquita
- Laboratory of Bioinformatics and Computational Biology, Department of Genetics and Molecular Biology, Federal University of Rio de Janeiro State (UNIRIO), Rio de Janeiro, Brazil
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Alsultan AA, Waller R, Heath PR, Kirby J. The genetics of amyotrophic lateral sclerosis: current insights. Degener Neurol Neuromuscul Dis 2016; 6:49-64. [PMID: 30050368 PMCID: PMC6053097 DOI: 10.2147/dnnd.s84956] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that results in loss of the upper and lower motor neurons from motor cortex, brainstem, and spinal cord. While the majority of cases are sporadic, approximately 10% show familial inheritance. ALS is usually inherited in an autosomal dominant manner, although autosomal recessive and X-linked inheritance do occur. To date, 24 of the genes at 26 loci have been identified; these include loci linked to ALS and to frontotemporal dementia-ALS, where family pedigrees contain individuals with frontotemporal dementia with/without ALS. The most commonly established genetic causes of familial ALS (FALS) to date are the presence of a hexanucleotide repeat expansion in the C9ORF72 gene (39.3% FALS) and mutation of SOD1, TARDBP, and FUS, with frequencies of 12%-23.5%, 5%, and 4.1%, respectively. However, with the increasing use of next-generation sequencing of small family pedigrees, this has led to an increasing number of genes being associated with ALS. This review provides a comprehensive review on the genetics of ALS and an update of the pathogenic mechanisms associated with these genes. Commonly implicated pathways have been established, including RNA processing, the protein degradation pathways of autophagy and ubiquitin-proteasome system, as well as protein trafficking and cytoskeletal function. Elucidating the role genetics plays in both FALS and sporadic ALS is essential for understanding the subsequent cellular dysregulation that leads to motor neuron loss, in order to develop future effective therapeutic strategies.
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Affiliation(s)
- Afnan A Alsultan
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK,
| | - Rachel Waller
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK,
| | - Paul R Heath
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK,
| | - Janine Kirby
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK,
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Mohagheghi F, Prudencio M, Stuani C, Cook C, Jansen-West K, Dickson DW, Petrucelli L, Buratti E. TDP-43 functions within a network of hnRNP proteins to inhibit the production of a truncated human SORT1 receptor. Hum Mol Genet 2015; 25:534-45. [PMID: 26614389 DOI: 10.1093/hmg/ddv491] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 11/24/2015] [Indexed: 12/13/2022] Open
Abstract
The aggregation and mislocalization of RNA-binding proteins leads to the aberrant regulation of RNA metabolism and is a key feature of many neurodegenerative diseases, including amyotrophic lateral sclerosis and frontotemporal dementia. However, the pathological consequences of abnormal deposition of TDP-43 and other RNA-binding proteins remain unclear, as the specific molecular events that drive neurodegeneration have been difficult to identify and continue to be elusive. Here, we provide novel insight into the complexity of the RNA-binding protein network by demonstrating that the inclusion of exon 17b in the SORT1 mRNA, a pathologically relevant splicing event known to be regulated by TDP-43, is also considerably affected by additional RNA-binding proteins, such as hnRNP L, PTB/nPTB and hnRNP A1/A2. Most importantly, the expression of hnRNP A1/A2 and PTB/nPTB is significantly altered in patients with frontotemporal dementia with TDP-43-positive inclusions (FTLD-TDP), indicating that perturbations in RNA metabolism and processing in FTLD-TDP are not exclusively driven by a loss of TDP-43 function. These results also suggest that a comprehensive assessment of the RNA-binding protein network will dramatically advance our current understanding of the role of TDP-43 in disease pathogenesis, as well as enhance both diagnostic and therapeutic capabilities.
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Affiliation(s)
- Fatemeh Mohagheghi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy and
| | - Mercedes Prudencio
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road S, Jacksonville, FL 32224, USA
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy and
| | - Casey Cook
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road S, Jacksonville, FL 32224, USA
| | - Karen Jansen-West
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road S, Jacksonville, FL 32224, USA
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road S, Jacksonville, FL 32224, USA
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road S, Jacksonville, FL 32224, USA
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy and
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