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Bregalda A, Carducci C, Viscomi MT, Pierigè F, Biagiotti S, Menotta M, Biancucci F, Pascucci T, Leuzzi V, Magnani M, Rossi L. Myelin basic protein recovery during PKU mice lifespan and the potential role of microRNAs on its regulation. Neurobiol Dis 2023; 180:106093. [PMID: 36948260 DOI: 10.1016/j.nbd.2023.106093] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/10/2023] [Accepted: 03/17/2023] [Indexed: 03/24/2023] Open
Abstract
Untreated phenylketonuria (PKU) patients and PKU animal models show hypomyelination in the central nervous system and white matter damages, which are accompanied by myelin basic protein (MBP) impairment. Despite many assumptions, the primary explanation of the mentioned cerebral outcomes remains elusive. In this study, MBP protein and mRNA expression on brains of wild type (WT) and phenylketonuric (ENU2) mice were analyzed throughout mice lifespan (14-60-180-270-360-540 post-natal days, PND). The results confirmed the low MBP expression at first PND times, while revealed an unprecedented progressive MBP protein expression recovery in aged ENU2 mice. Unexpectedly, unaltered MBP mRNA expression between WT and ENU2 was always observed. Additionally, for the same time intervals, a significant decrease of the phenylalanine concentration in the peripheral blood and brain of ENU2 mice was detected, to date, for the first time. In this scenario, a translational hindrance of MBP during initial and late cerebral development in ENU2 mice was hypothesized, leading to the execution of a microRNA microarray analysis on 60 PND brains, which was followed by a proteomic assay on 60 and 360 PND brains in order to validate in silico miRNA-target predictions. Taken together, miR-218 - 1-3p, miR - 1231-3p and miR-217-5p were considered as the most impactful microRNAs, since a downregulation of their potential targets (MAG, CNTNAP2 and ANLN, respectively) can indirectly lead to a low MBP protein expression. These miRNAs, in addition, follow an opposite expression trend compared to MBP during adulthood, and their target proteins revealed a complete normalization in aged ENU2 mice. In conclusion, these results provide a new perspective on the PKU pathophysiology understanding and on a possible treatment, emphasizing the potential modulating role of differentially expressed microRNAs in MBP expression on PKU brains during PKU mouse lifespan.
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Affiliation(s)
- Alessandro Bregalda
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy.
| | - Claudia Carducci
- Department of Experimental Medicine, Sapienza University, viale del Policlinico 155, 00161 Rome, Italy
| | - Maria Teresa Viscomi
- Department of Life Sciences and Public Health, Sect. Histology and Embryology, Università Cattolica del S. Cuore, Largo F. Vito 1, 00168 Rome, Italy; Fondazione Policlinico Universitario "Agostino Gemelli", IRCCS, 00168 Rome, Italy
| | - Francesca Pierigè
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Sara Biagiotti
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Michele Menotta
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Federica Biancucci
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy
| | - Tiziana Pascucci
- Fondazione Santa Lucia IRCCS, via Ardeatina 306, 00142 Rome, Italy; Department of Psychology and Centro "Daniel Bovet", Sapienza University, via dei Marsi 78, 00185 Rome, Italy
| | - Vincenzo Leuzzi
- Department of Human Neuroscience, Sapienza University, via dei Sabelli 108, 00185 Rome, Italy
| | - Mauro Magnani
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy; EryDel SpA, via Antonio Meucci 3, 20091 Bresso, Milan, Italy
| | - Luigia Rossi
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", via Saffi 2, 61029 Urbino, PU, Italy; EryDel SpA, via Antonio Meucci 3, 20091 Bresso, Milan, Italy
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2
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The case of a patient with MIRAGE syndrome with familial dysautonomia-like symptoms. Hum Genome Var 2021; 8:27. [PMID: 34253717 PMCID: PMC8275606 DOI: 10.1038/s41439-021-00158-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/25/2021] [Accepted: 06/18/2021] [Indexed: 11/08/2022] Open
Abstract
We describe a case of posthumously diagnosed MIRAGE syndrome (Myelodysplasia, Infection, Restriction of growth, Adrenal hypoplasia, Genital problems, and Enteropathy) in a girl with a new pathogenic SAMD9 variant (p.F437S), who was initially considered to have familial dysautonomia (FD)-like disease due to increased levels of catecholamine metabolites. Functional analyses of F437S-SAMD9 were performed, showing characteristics of disease-causing variants. This new SAMD9 variant (p.F437S) also causes MIRAGE syndrome.
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Yannai S, Zonszain J, Donyo M, Ast G. Combinatorial treatment increases IKAP levels in human cells generated from Familial Dysautonomia patients. PLoS One 2019; 14:e0211602. [PMID: 30889183 PMCID: PMC6424424 DOI: 10.1371/journal.pone.0211602] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 03/07/2019] [Indexed: 02/06/2023] Open
Abstract
Familial Dysautonomia (FD) is an autosomal recessive congenital neuropathy that results from a point mutation at the 5' splice site of intron 20 in the IKBKAP gene. This mutation decreases production of the IKAP protein, and treatments that increase the level of the full-length IKBKAP transcript are likely to be of therapeutic value. We previously found that phosphatidylserine (PS), an FDA-approved food supplement, elevates IKAP levels in cells generated from FD patients. Here we demonstrate that combined treatment of cells generated from FD patients with PS and kinetin or PS and the histone deacetylase inhibitor trichostatin A (TSA) resulted in an additive elevation of IKAP compared to each drug alone. This indicates that the compounds influence different pathways. We also found that pridopidine enhances production of IKAP in cells generated from FD patients. Pridopidine has an additive effect on IKAP levels when used in combination with kinetin or TSA, but not with PS; suggesting that PS and pridopidine influence IKBKAP levels through the same mechanism. Indeed, we demonstrate that the effect of PS and pridopidine is through sigma-1 receptor-mediated activation of the BDNF signaling pathway. A combination treatment with any of these drugs with different mechanisms has potential to benefit FD patients.
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Affiliation(s)
- Sivan Yannai
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Jonathan Zonszain
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Maya Donyo
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Gil Ast
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
- * E-mail:
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Rubin BY, Anderson SL. IKBKAP/ELP1 gene mutations: mechanisms of familial dysautonomia and gene-targeting therapies. APPLICATION OF CLINICAL GENETICS 2017; 10:95-103. [PMID: 29290691 PMCID: PMC5735983 DOI: 10.2147/tacg.s129638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The successful completion of the Human Genome Project led to the discovery of the molecular basis of thousands of genetic disorders. The identification of the mutations that cause familial dysautonomia (FD), an autosomal recessive disorder that impacts sensory and autonomic neurons, was aided by the release of the human DNA sequence. The identification and characterization of the genetic cause of FD have changed the natural history of this disease. Genetic testing programs, which were established shortly after the disease-causing mutations were identified, have almost completely eliminated the birth of children with this disorder. Characterization of the principal disease-causing mutation has led to the development of therapeutic modalities that ameliorate its effect, while the development of mouse models that recapitulate the impact of the mutation has allowed for the in-depth characterization of its impact on neuronal development and survival. The intense research focus on this disorder, while clearly benefiting the FD patient population, also serves as a model for the positive impact focused research efforts can have on the future of other genetic diseases. Here, we present the research advances and scientific breakthroughs that have changed and will continue to change the natural history of this centuries-old genetic disease.
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Affiliation(s)
- Berish Y Rubin
- Department of Biological Sciences, Fordham University, Bronx, NY, USA
| | - Sylvia L Anderson
- Department of Biological Sciences, Fordham University, Bronx, NY, USA
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5
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Naftelberg S, Abramovitch Z, Gluska S, Yannai S, Joshi Y, Donyo M, Ben-Yaakov K, Gradus T, Zonszain J, Farhy C, Ashery-Padan R, Perlson E, Ast G. Phosphatidylserine Ameliorates Neurodegenerative Symptoms and Enhances Axonal Transport in a Mouse Model of Familial Dysautonomia. PLoS Genet 2016; 12:e1006486. [PMID: 27997532 PMCID: PMC5172536 DOI: 10.1371/journal.pgen.1006486] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 11/15/2016] [Indexed: 12/03/2022] Open
Abstract
Familial Dysautonomia (FD) is a neurodegenerative disease in which aberrant tissue-specific splicing of IKBKAP exon 20 leads to reduction of IKAP protein levels in neuronal tissues. Here we generated a conditional knockout (CKO) mouse in which exon 20 of IKBKAP is deleted in the nervous system. The CKO FD mice exhibit developmental delays, sensory abnormalities, and less organized dorsal root ganglia (DRGs) with attenuated axons compared to wild-type mice. Furthermore, the CKO FD DRGs show elevated HDAC6 levels, reduced acetylated α-tubulin, unstable microtubules, and impairment of axonal retrograde transport of nerve growth factor (NGF). These abnormalities in DRG properties underlie neuronal degeneration and FD symptoms. Phosphatidylserine treatment decreased HDAC6 levels and thus increased acetylation of α-tubulin. Further PS treatment resulted in recovery of axonal outgrowth and enhanced retrograde axonal transport by decreasing histone deacetylase 6 (HDAC6) levels and thus increasing acetylation of α-tubulin levels. Thus, we have identified the molecular pathway that leads to neurodegeneration in FD and have demonstrated that phosphatidylserine treatment has the potential to slow progression of neurodegeneration. We create a novel FD mouse model, in which exon 20 of IKBKAP was deleted in the nervous system, to study the role of IKAP in the neurodegeneration process. The lack of IKBKAP exon 20 impaired retrograde nerve growth factor (NGF) transport and axonal outgrowth. Reduction of IKAP levels resulted in elevated HDAC6 levels and thus reduced acetylated α-tubulin levels. Phosphatidylserine down-regulated HDAC6 levels, furthermore phosphatidylserine treatment facilitated axonal transport and stabilized microtubules. In brief: Naftelberg et al. identify the molecular pathway leading to neurodegeneration using a mouse model of familial dysautonomia and suggest that phosphatidylserine acts as an HDAC6 inhibitor to improve neurologic function.
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Affiliation(s)
- Shiran Naftelberg
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ziv Abramovitch
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Shani Gluska
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sivan Yannai
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yuvraj Joshi
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Maya Donyo
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Keren Ben-Yaakov
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Tal Gradus
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Jonathan Zonszain
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Chen Farhy
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ruth Ashery-Padan
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Eran Perlson
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- * E-mail: (EP); (GA)
| | - Gil Ast
- Department of Human Molecular Genetics and Biochemestry. Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- * E-mail: (EP); (GA)
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6
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Lim JL, van der Pol SMA, Baron W, McCord JM, de Vries HE, van Horssen J. Protandim Protects Oligodendrocytes against an Oxidative Insult. Antioxidants (Basel) 2016; 5:antiox5030030. [PMID: 27618111 PMCID: PMC5039579 DOI: 10.3390/antiox5030030] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 08/02/2016] [Indexed: 01/23/2023] Open
Abstract
Oligodendrocyte damage and loss are key features of multiple sclerosis (MS) pathology. Oligodendrocytes appear to be particularly vulnerable to reactive oxygen species (ROS) and cytokines, such as tumor necrosis factor-α (TNF), which induce cell death and prevent the differentiation of oligodendrocyte progenitor cells (OPCs). Here, we investigated the efficacy of sulforaphane (SFN), monomethyl fumarate (MMF) and Protandim to induce Nrf2-regulated antioxidant enzyme expression, and protect oligodendrocytes against ROS-induced cell death and ROS-and TNF-mediated inhibition of OPC differentiation. OLN-93 cells and primary rat oligodendrocytes were treated with SFN, MMF or Protandim resulting in significant induction of Nrf2-driven (antioxidant) proteins heme oygenase-1, nicotinamide adenine dinucleotide phosphate (NADPH): quinone oxidoreductase-1 and p62/SQSTM1, as analysed by Western blotting. After incubation with the compounds, oligodendrocytes were exposed to hydrogen peroxide. Protandim most potently promoted oligodendrocyte cell survival as measured by live/death viability assay. Moreover, OPCs were treated with Protandim or vehicle control prior to exposing them to TNF or hydrogen peroxide for five days, which inhibited OPC differentiation. Protandim significantly promoted OPC differentiation under influence of ROS, but not TNF. Protandim, a combination of five herbal ingredients, potently induces antioxidants in oligodendrocytes and is able to protect oligodendrocytes against oxidative stress by preventing ROS-induced cell death and promoting OPC differentiation.
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Affiliation(s)
- Jamie L Lim
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Neuroscience Campus Amsterdam, 1081 HZ Amsterdam, the Netherlands.
| | - Susanne M A van der Pol
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Neuroscience Campus Amsterdam, 1081 HZ Amsterdam, the Netherlands.
| | - Wia Baron
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, the Netherlands.
| | - Joe M McCord
- Department of Medicine, Division of Pulmonary Science and Critical Care Medicine, University of Colorado at Denver, Aurora, CO 80045, USA.
| | - Helga E de Vries
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Neuroscience Campus Amsterdam, 1081 HZ Amsterdam, the Netherlands.
| | - Jack van Horssen
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Neuroscience Campus Amsterdam, 1081 HZ Amsterdam, the Netherlands.
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7
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Dietrich P, Dragatsis I. Familial Dysautonomia: Mechanisms and Models. Genet Mol Biol 2016; 39:497-514. [PMID: 27561110 PMCID: PMC5127153 DOI: 10.1590/1678-4685-gmb-2015-0335] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 03/16/2016] [Indexed: 11/22/2022] Open
Abstract
Hereditary Sensory and Autonomic Neuropathies (HSANs) compose a heterogeneous group of genetic disorders characterized by sensory and autonomic dysfunctions. Familial Dysautonomia (FD), also known as HSAN III, is an autosomal recessive disorder that affects 1/3,600 live births in the Ashkenazi Jewish population. The major features of the disease are already present at birth and are attributed to abnormal development and progressive degeneration of the sensory and autonomic nervous systems. Despite clinical interventions, the disease is inevitably fatal. FD is caused by a point mutation in intron 20 of the IKBKAP gene that results in severe reduction in expression of IKAP, its encoded protein. In vitro and in vivo studies have shown that IKAP is involved in multiple intracellular processes, and suggest that failed target innervation and/or impaired neurotrophic retrograde transport are the primary causes of neuronal cell death in FD. However, FD is far more complex, and appears to affect several other organs and systems in addition to the peripheral nervous system. With the recent generation of mouse models that recapitulate the molecular and pathological features of the disease, it is now possible to further investigate the mechanisms underlying different aspects of the disorder, and to test novel therapeutic strategies.
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Affiliation(s)
- Paula Dietrich
- Department of Physiology, The University of Tennessee, Memphis, TN, USA
| | - Ioannis Dragatsis
- Department of Physiology, The University of Tennessee, Memphis, TN, USA
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Smith FL, Davis RL. Organ of Corti explants direct tonotopically graded morphology of spiral ganglion neurons in vitro. J Comp Neurol 2016; 524:2182-207. [PMID: 26663318 DOI: 10.1002/cne.23940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Revised: 11/12/2015] [Accepted: 11/30/2015] [Indexed: 01/25/2023]
Abstract
The spiral ganglion is a compelling model system to examine how morphological form contributes to sensory function. While the ganglion is composed mainly of a single class of type I neurons that make simple one-to-one connections with inner hair cell sensory receptors, it has an elaborate overall morphological design. Specific features, such as soma size and axon outgrowth, are graded along the spiral contour of the cochlea. To begin to understand the interplay between different regulators of neuronal morphology, we cocultured neuron explants with peripheral target tissues removed from distinct cochlear locations. Interestingly, these "hair cell microisolates" were capable of both increasing and decreasing neuronal somata size, without adversely affecting survival. Moreover, axon characteristics elaborated de novo by the primary afferents in culture were systematically regulated by the sensory endorgan. Apparent peripheral nervous system (PNS)-like and central nervous system (CNS)-like axonal profiles were established in our cocultures allowing an analysis of putative PNS/CNS axon length ratios. As predicted from the in vivo organization, PNS-like axon bundles elaborated by apical cocultures were longer than their basal counterparts and this phenotype was methodically altered when neuron explants were cocultured with microisolates from disparate cochlear regions. Thus, location-dependent signals within the organ of Corti may set the "address" of neurons within the spiral ganglion, allowing them to elaborate the appropriate tonotopically associated morphological features in order to carry out their signaling function. J. Comp. Neurol. 524:2182-2207, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Felicia L Smith
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey, USA
| | - Robin L Davis
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey, USA
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Norcliffe-Kaufmann L, Slaugenhaupt SA, Kaufmann H. Familial dysautonomia: History, genotype, phenotype and translational research. Prog Neurobiol 2016; 152:131-148. [PMID: 27317387 DOI: 10.1016/j.pneurobio.2016.06.003] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 06/10/2016] [Accepted: 06/11/2016] [Indexed: 01/30/2023]
Abstract
Familial dysautonomia (FD) is a rare neurological disorder caused by a splice mutation in the IKBKAP gene. The mutation arose in the 1500s within the small Jewish founder population in Eastern Europe and became prevalent during the period of rapid population expansion within the Pale of Settlement. The carrier rate is 1:32 in Jews descending from this region. The mutation results in a tissue-specific deficiency in IKAP, a protein involved in the development and survival of neurons. Patients homozygous for the mutations are born with multiple lesions affecting mostly sensory (afferent) fibers, which leads to widespread organ dysfunction and increased mortality. Neurodegenerative features of the disease include progressive optic atrophy and worsening gait ataxia. Here we review the progress made in the last decade to better understand the genotype and phenotype. We also discuss the challenges of conducting controlled clinical trials in this rare medically fragile population. Meanwhile, the search for better treatments as well as a neuroprotective agent is ongoing.
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Affiliation(s)
| | - Susan A Slaugenhaupt
- Center for Human Genetic Research, Massachusetts General Hospital Research Institute and Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Horacio Kaufmann
- Department of Neurology, New York University School of Medicine, New York, NY, USA.
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10
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Dimerization of elongator protein 1 is essential for Elongator complex assembly. Proc Natl Acad Sci U S A 2015; 112:10697-702. [PMID: 26261306 DOI: 10.1073/pnas.1502597112] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The evolutionarily conserved Elongator complex, which is composed of six subunits elongator protein 1 (Elp1 to -6), plays vital roles in gene regulation. The molecular hallmark of familial dysautonomia (FD) is the splicing mutation of Elp1 [also known as IκB kinase complex-associated protein (IKAP)] in the nervous system that is believed to be the primary cause of the devastating symptoms of this disease. Here, we demonstrate that disease-related mutations in Elp1 affect Elongator assembly, and we have determined the structure of the C-terminal portion of human Elp1 (Elp1-CT), which is sufficient for full-length Elp1 dimerization, as well as the structure of the cognate dimerization domain of yeast Elp1 (yElp1-DD). Our study reveals that the formation of the Elp1 dimer contributes to its stability in vitro and in vivo and is required for the assembly of both the human and yeast Elongator complexes. Functional studies suggest that Elp1 dimerization is essential for yeast viability. Collectively, our results identify the evolutionarily conserved dimerization domain of Elp1 and suggest that the pathological mechanisms underlying the onset and progression of Elp1 mutation-related disease may result from impaired Elongator activities.
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Ohe K, Hagiwara M. Modulation of alternative splicing with chemical compounds in new therapeutics for human diseases. ACS Chem Biol 2015; 10:914-24. [PMID: 25560473 DOI: 10.1021/cb500697f] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alternative splicing is a critical step where a limited number of human genes generate a complex and diverse proteome. Various diseases, including inherited diseases with abnormalities in the "genome code," have been found to result in an aberrant mis-spliced "transcript code" with correlation to the resulting phenotype. Chemical compound-based and nucleic acid-based strategies are trying to target this mis-spliced "transcript code". We will briefly mention about how to obtain splicing-modifying-compounds by high-throughput screening and overview of what is known about compounds that modify splicing pathways. The main focus will be on RNA-binding protein kinase inhibitors. In the main text, we will refer to diseases where splicing-modifying-compounds have been intensively investigated, with comparison to nucleic acid-based strategies. The information on their involvement in mis-splicing as well as nonsplicing events will be helpful in finding better compounds with less off-target effects for future implications in mis-splicing therapy.
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Affiliation(s)
- Kenji Ohe
- †Department of Anatomy and Developmental Biology and ‡Training Program of Leaders for Integrated Medical System for Fruitful Healthy-Longevity Society (LIMS), Kyoto University Graduate School of Medicine, Kyoto 606-8315, Japan
| | - Masatoshi Hagiwara
- †Department of Anatomy and Developmental Biology and ‡Training Program of Leaders for Integrated Medical System for Fruitful Healthy-Longevity Society (LIMS), Kyoto University Graduate School of Medicine, Kyoto 606-8315, Japan
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