151
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Huntington Disease as a Neurodevelopmental Disorder and Early Signs of the Disease in Stem Cells. Mol Neurobiol 2017; 55:3351-3371. [PMID: 28497201 PMCID: PMC5842500 DOI: 10.1007/s12035-017-0477-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 03/01/2017] [Indexed: 02/07/2023]
Abstract
Huntington disease (HD) is a dominantly inherited disorder caused by a CAG expansion mutation in the huntingtin (HTT) gene, which results in the HTT protein that contains an expanded polyglutamine tract. The adult form of HD exhibits a late onset of the fully symptomatic phase. However, there is also a long presymptomatic phase, which has been increasingly investigated and recognized as important for the disease development. Moreover, the juvenile form of HD, evoked by a higher number of CAG repeats, resembles a neurodevelopmental disorder and has recently been the focus of additional interest. Multiple lines of data, such as the developmental necessity of HTT, its role in the cell cycle and neurogenesis, and findings from pluripotent stem cells, suggest the existence of a neurodevelopmental component in HD pathogenesis. Therefore, we discuss the early molecular pathogenesis of HD in pluripotent and neural stem cells, with respect to the neurodevelopmental aspects of HD.
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152
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Shin A, Shin B, Shin JW, Kim KH, Atwal RS, Hope JM, Gillis T, Leszyk JD, Shaffer SA, Lee R, Kwak S, MacDonald ME, Gusella JF, Seong IS, Lee JM. Novel allele-specific quantification methods reveal no effects of adult onset CAG repeats on HTT mRNA and protein levels. Hum Mol Genet 2017; 26:1258-1267. [PMID: 28165127 PMCID: PMC6075029 DOI: 10.1093/hmg/ddx033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 12/08/2016] [Accepted: 01/19/2017] [Indexed: 01/26/2023] Open
Abstract
Huntington's disease (HD) reflects dominant consequences of a CAG repeat expansion mutation in HTT. Expanded CAG repeat size is the primary determinant of age at onset and age at death in HD. Although HD pathogenesis is driven by the expanded CAG repeat, whether the mutation influences the expression levels of mRNA and protein from the disease allele is not clear due to the lack of sensitive allele-specific quantification methods and the presence of confounding factors. To determine the impact of CAG expansion at the molecular level, we have developed novel allele-specific HTT mRNA and protein quantification methods based on principles of multiplex ligation-dependent probe amplification and targeted MS/MS parallel reaction monitoring, respectively. These assays, exhibiting high levels of specificity and sensitivity, were designed to distinguish allelic products based upon expressed polymorphic variants in HTT, including rs149 109 767. To control for other cis-haplotype variations, we applied allele-specific quantification assays to a panel of HD lymphoblastoid cell lines, each carrying the major European disease haplotype (i.e. hap.01) on the mutant chromosome. We found that steady state levels of HTT mRNA and protein were not associated with expanded CAG repeat length. Rather, the products of mutant and normal alleles, both mRNA and protein, were balanced, thereby arguing that a cis-regulatory effect of the expanded CAG repeat is not a critical component of the underlying mechanism of HD. These robust allele-specific assays could prove valuable for monitoring the impact of allele-specific gene silencing strategies currently being explored as therapeutic interventions in HD.
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Affiliation(s)
- Aram Shin
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Baehyun Shin
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Jun Wan Shin
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Kyung-Hee Kim
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Ranjit S. Atwal
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Jennifer M. Hope
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Tammy Gillis
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - John D. Leszyk
- Proteomics and Mass Spectrometry Facility, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Scott A. Shaffer
- Proteomics and Mass Spectrometry Facility, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Ramee Lee
- CHDI Foundation, Princeton, NJ 08540, USA
| | - Seung Kwak
- CHDI Foundation, Princeton, NJ 08540, USA
| | - Marcy E. MacDonald
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Medical and Population Genetics Program, The Broad Institute of M.I.T. and Harvard, Cambridge, MA 02142, USA
| | - James F. Gusella
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Medical and Population Genetics Program, The Broad Institute of M.I.T. and Harvard, Cambridge, MA 02142, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Ihn Sik Seong
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Jong-Min Lee
- Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
- Medical and Population Genetics Program, The Broad Institute of M.I.T. and Harvard, Cambridge, MA 02142, USA
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153
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Yu MS, Tanese N. Huntingtin Is Required for Neural But Not Cardiac/Pancreatic Progenitor Differentiation of Mouse Embryonic Stem Cells In vitro. Front Cell Neurosci 2017; 11:33. [PMID: 28270748 PMCID: PMC5318384 DOI: 10.3389/fncel.2017.00033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 02/06/2017] [Indexed: 12/25/2022] Open
Abstract
Mutation in the huntingtin (HTT) gene causes Huntington's disease (HD). It is an autosomal dominant trinucleotide-repeat expansion disease in which CAG repeat sequence expands to >35. This results in the production of mutant HTT protein with an increased stretch of glutamines near the N-terminus. The wild type HTT gene encodes a 350 kD protein whose function remains elusive. Mutant HTT protein has been implicated in transcription, axonal transport, cytoskeletal structure/function, signal transduction, and autophagy. HD is characterized by the appearance of nuclear inclusions and degeneration of the striatum. Although HTT protein is expressed early in embryos, most patients develop symptoms in mid-life. It is also unclear why the ubiquitously expressed mutant HTT specifically causes striatal atrophy. Wild type Htt is essential for development as Htt knockout mice die at day E7.5. Increasing evidence suggests mutant Htt may alter neurogenesis and development of striatal neurons resulting in neuronal loss. Using a mouse embryonic stem cell model, we examined the role of Htt in neural differentiation. We found cells lacking Htt inefficient in generating neural stem cells. In contrast differentiation into progenitors of mesoderm and endoderm lineages was not affected. The data suggests Htt is essential for neural but not cardiac/pancreatic progenitor differentiation of embryonic stem cells in vitro.
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Affiliation(s)
- Man Shan Yu
- Department of Microbiology, New York University School of Medicine, New York NY, USA
| | - Naoko Tanese
- Department of Microbiology, New York University School of Medicine, New York NY, USA
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154
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Adegbuyiro A, Sedighi F, Pilkington AW, Groover S, Legleiter J. Proteins Containing Expanded Polyglutamine Tracts and Neurodegenerative Disease. Biochemistry 2017; 56:1199-1217. [PMID: 28170216 DOI: 10.1021/acs.biochem.6b00936] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Several hereditary neurological and neuromuscular diseases are caused by an abnormal expansion of trinucleotide repeats. To date, there have been 10 of these trinucleotide repeat disorders associated with an expansion of the codon CAG encoding glutamine (Q). For these polyglutamine (polyQ) diseases, there is a critical threshold length of the CAG repeat required for disease, and further expansion beyond this threshold is correlated with age of onset and symptom severity. PolyQ expansion in the translated proteins promotes their self-assembly into a variety of oligomeric and fibrillar aggregate species that accumulate into the hallmark proteinaceous inclusion bodies associated with each disease. Here, we review aggregation mechanisms of proteins with expanded polyQ-tracts, structural consequences of expanded polyQ ranging from monomers to fibrillar aggregates, the impact of protein context and post-translational modifications on aggregation, and a potential role for lipid membranes in aggregation. As the pathogenic mechanisms that underlie these disorders are often classified as either a gain of toxic function or loss of normal protein function, some toxic mechanisms associated with mutant polyQ tracts will also be discussed.
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Affiliation(s)
- Adewale Adegbuyiro
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Faezeh Sedighi
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Albert W Pilkington
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Sharon Groover
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States.,Blanchette Rockefeller Neurosciences Institute, Robert C. Byrd Health Sciences Center, P.O. Box 9304, West Virginia University , Morgantown, West Virginia 26506, United States.,NanoSAFE, P.O. Box 6223, West Virginia University , Morgantown, West Virginia 26506, United States
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155
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Tartaglione AM, Popoli P, Calamandrei G. Regenerative medicine in Huntington's disease: Strengths and weaknesses of preclinical studies. Neurosci Biobehav Rev 2017; 77:32-47. [PMID: 28223129 DOI: 10.1016/j.neubiorev.2017.02.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/26/2017] [Accepted: 02/17/2017] [Indexed: 01/22/2023]
Abstract
Huntington's disease (HD) is an inherited neurodegenerative disorder, characterized by impairment in motor, cognitive and psychiatric domains. Currently, there is no specific therapy to act on the onset or progression of HD. The marked neuronal death observed in HD is a main argument in favour of stem cells (SCs) transplantation as a promising therapeutic perspective to replace the population of lost neurons and restore the functionality of the damaged circuitry. The availability of rodent models of HD encourages the investigation of the restorative potential of SCs transplantation longitudinally. However, the results of preclinical studies on SCs therapy in HD are so far largely inconsistent; this hampers the individuation of the more appropriate model and precludes the comparative analysis of transplant efficacy on behavioural end points. Thus, this review will describe the state of the art of in vivo research on SCs therapy in HD, analysing in a translational perspective the strengths and weaknesses of animal studies investigating the therapeutic potential of cell transplantation on HD progression.
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Affiliation(s)
- A M Tartaglione
- Centre for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy
| | - P Popoli
- National Centre for Medicines Research and Preclinical/Clinical Evaluation, Rome, Italy
| | - G Calamandrei
- Centre for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, Rome, Italy.
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156
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Abstract
Huntington disease (HD) is an autosomal dominant, neurodegenerative disorder with a primary etiology of striatal pathology. The Huntingtin gene (HTT) has a unique feature of a DNA trinucleotide (triplet) repeat, with repeat length ranging from 10 to 35 in the normal population. Repeat lengths between 36 and 39 cause HD at reduced penetrance (some will get the disease, others won't) and when expanded to 40 or more repeats (mHTT), causes HD at full penetrance (every person with this length or beyond will definitely develop the disease). The symptoms of HD may be motor, cognitive, and psychiatric, and are consistent with the pathophysiology of frontostriatal circuitry malfunction. Expressed ubiquitously and throughout the entire life cycle (development through adulthood), mHTT causes initial dysfunction and eventual death of a specific cell population within the striatum. Although all areas of the brain are eventually affected, the primary pathology of the disease is regionally specific. As a single-gene disorder, HD has the distinction of having the potential of treatment that is aimed directly at the known pathogenic mechanism by gene silencing, providing hope for neuroprotection and ultimately, prevention.
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Affiliation(s)
- Peggy C Nopoulos
- Department of Psychiatry, University of Iowa, Iowa City, Iowa, USA
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157
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Huntingtin-Mediated Multipolar-Bipolar Transition of Newborn Cortical Neurons Is Critical for Their Postnatal Neuronal Morphology. Neuron 2017; 93:99-114. [DOI: 10.1016/j.neuron.2016.11.035] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 09/25/2016] [Accepted: 11/16/2016] [Indexed: 01/05/2023]
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158
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Fruhmann G, Seynnaeve D, Zheng J, Ven K, Molenberghs S, Wilms T, Liu B, Winderickx J, Franssens V. Yeast buddies helping to unravel the complexity of neurodegenerative disorders. Mech Ageing Dev 2017; 161:288-305. [DOI: 10.1016/j.mad.2016.05.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 04/22/2016] [Accepted: 05/02/2016] [Indexed: 12/31/2022]
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159
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Wright DJ, Renoir T, Gray LJ, Hannan AJ. Huntington’s Disease: Pathogenic Mechanisms and Therapeutic Targets. ADVANCES IN NEUROBIOLOGY 2017; 15:93-128. [DOI: 10.1007/978-3-319-57193-5_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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160
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Foxa1 is essential for development and functional integrity of the subthalamic nucleus. Sci Rep 2016; 6:38611. [PMID: 27934886 PMCID: PMC5146925 DOI: 10.1038/srep38611] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 11/10/2016] [Indexed: 01/15/2023] Open
Abstract
Inactivation of transcription factor Foxa1 in mice results in neonatal mortality of unknown cause. Here, we report that ablation of Foxa1 causes impaired development and loss of the subthalamic nucleus (STN). Functional deficits in the STN have been implicated in the etiology of Huntington's and Parkinson's disease. We show that neuronal ablation by Synapsin1-Cre-mediated Foxa1 deletion is sufficient to induce hyperlocomotion in mice. Transcriptome profiling of STN neurons in conditional Foxa1 knockout mice revealed changes in gene expression reminiscent of those in neurodegenerative diseases. We identified Ppargc1a, a transcriptional co-activator that is implicated in neurodegeneration, as a Foxa1 target. These findings were substantiated by the observation of Foxa1-dependent demise of STN neurons in conditional models of Foxa1 mutant mice. Finally, we show that the spontaneous firing activity of Foxa1-deficient STN neurons is profoundly impaired. Our data reveal so far elusive roles of Foxa1 in the development and maintenance of STN function.
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161
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Casaca-Carreira J, Toonen LJ, Evers MM, Jahanshahi A, van-Roon-Mom WM, Temel Y. In vivo proof-of-concept of removal of the huntingtin caspase cleavage motif-encoding exon 12 approach in the YAC128 mouse model of Huntington’s disease. Biomed Pharmacother 2016; 84:93-96. [DOI: 10.1016/j.biopha.2016.09.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/25/2016] [Accepted: 09/05/2016] [Indexed: 12/17/2022] Open
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162
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Lokhande S, Patra BN, Ray A. A link between chromatin condensation mechanisms and Huntington's disease: connecting the dots. MOLECULAR BIOSYSTEMS 2016; 12:3515-3529. [PMID: 27714015 DOI: 10.1039/c6mb00598e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Huntington's disease is a rare neurodegenerative disorder whose complex pathophysiology exhibits system-wide changes in the body, with striking and debilitating clinical features targeting the central nervous system. Among the various molecular functions affected in this disease, mitochondrial dysfunction and transcriptional dysregulation are some of the most studied aspects of this disease. However, there is evidence of the involvement of a mutant Huntingtin protein in the processes of DNA damage, chromosome condensation and DNA repair. This review attempts to briefly recapitulate the clinical features, model systems used to study the disease, major molecular processes affected, and, more importantly, examines recent evidence for the involvement of the mutant Huntingtin protein in the processes regulating chromosome condensation, leading to DNA damage response and neuronal death.
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Affiliation(s)
- Sonali Lokhande
- Keck Graduate Institute of Applied Life Sciences, Claremont, CA 91711, USA.
| | - Biranchi N Patra
- Keck Graduate Institute of Applied Life Sciences, Claremont, CA 91711, USA.
| | - Animesh Ray
- Keck Graduate Institute of Applied Life Sciences, Claremont, CA 91711, USA.
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163
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Nelson CS, Beck JN, Wilson KA, Pilcher ER, Kapahi P, Brem RB. Cross-phenotype association tests uncover genes mediating nutrient response in Drosophila. BMC Genomics 2016; 17:867. [PMID: 27809764 PMCID: PMC5095962 DOI: 10.1186/s12864-016-3137-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 09/28/2016] [Indexed: 11/14/2022] Open
Abstract
Background Obesity-related diseases are major contributors to morbidity and mortality in the developed world. Molecular diagnostics and targets of therapies to combat nutritional imbalance are urgently needed in the clinic. Invertebrate animals have been a cornerstone of basic research efforts to dissect the genetics of metabolism and nutrient response. We set out to use fruit flies reared on restricted and nutrient-rich diets to identify genes associated with starvation resistance, body mass and composition, in a survey of genetic variation across the Drosophila Genetic Reference Panel (DGRP). Results We measured starvation resistance, body weight and composition in DGRP lines on each of two diets and used several association mapping strategies to harness this panel of phenotypes for molecular insights. We tested DNA sequence variants for a relationship with single metabolic traits and with multiple traits at once, using a scheme for cross-phenotype association mapping; we focused our association tests on homologs of human disease genes and common polymorphisms; and we tested for gene-by-diet interactions. The results revealed gene and gene-by-diet associations between 17 variants and body mass, whole-body triglyceride and glucose content, or starvation resistance. Focused molecular experiments validated the role in body mass of an uncharacterized gene, CG43921 (which we rename heavyweight), and previously unknown functions for the diacylglycerol kinase rdgA, the huntingtin homolog htt, and the ceramide synthase schlank in nutrient-dependent body mass, starvation resistance, and lifespan. Conclusions Our findings implicate a wealth of gene candidates in fly metabolism and nutrient response, and ascribe novel functions to htt, rdgA, hwt and schlank. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3137-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Christopher S Nelson
- Buck Institute for Research on Aging, 8001 Redwood Blvd., Novato, CA, 94947, USA
| | - Jennifer N Beck
- Buck Institute for Research on Aging, 8001 Redwood Blvd., Novato, CA, 94947, USA.,Department of Urology, University of California, San Francisco, CA, USA
| | - Kenneth A Wilson
- Buck Institute for Research on Aging, 8001 Redwood Blvd., Novato, CA, 94947, USA.,Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Elijah R Pilcher
- Buck Institute for Research on Aging, 8001 Redwood Blvd., Novato, CA, 94947, USA
| | - Pankaj Kapahi
- Buck Institute for Research on Aging, 8001 Redwood Blvd., Novato, CA, 94947, USA. .,Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA. .,Department of Urology, University of California, San Francisco, CA, USA.
| | - Rachel B Brem
- Buck Institute for Research on Aging, 8001 Redwood Blvd., Novato, CA, 94947, USA. .,Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA. .,Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, USA.
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164
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Arteaga-Bracho EE, Gulinello M, Winchester ML, Pichamoorthy N, Petronglo JR, Zambrano AD, Inocencio J, De Jesus CD, Louie JO, Gokhan S, Mehler MF, Molero AE. Postnatal and adult consequences of loss of huntingtin during development: Implications for Huntington's disease. Neurobiol Dis 2016; 96:144-155. [PMID: 27623015 DOI: 10.1016/j.nbd.2016.09.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/25/2016] [Accepted: 09/06/2016] [Indexed: 12/25/2022] Open
Abstract
The mutation in huntingtin (mHtt) leads to a spectrum of impairments in the developing forebrain of Huntington's disease (HD) mouse models. Whether these developmental alterations are due to loss- or gain-of-function mechanisms and contribute to HD pathogenesis is unknown. We examined the role of selective loss of huntingtin (Htt) function during development on postnatal vulnerability to cell death. We employed mice expressing very low levels of Htt throughout embryonic life to postnatal day 21 (Hdhd•hyp). We demonstrated that Hdhd•hyp mice exhibit: (1) late-life striatal and cortical neuronal degeneration; (2) neurological and skeletal muscle alterations; and (3) white matter tract impairments and axonal degeneration. Hdhd•hyp embryos also exhibited subpallial heterotopias, aberrant striatal maturation and deregulation of gliogenesis. These results indicate that developmental deficits associated with Htt functions render cells present at discrete neural foci increasingly susceptible to cell death, thus implying the potential existence of a loss-of-function developmental component to HD pathogenesis.
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Affiliation(s)
- Eduardo E Arteaga-Bracho
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Maria Gulinello
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA; Behavioral Core Facility, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Michael L Winchester
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Nandini Pichamoorthy
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Jenna R Petronglo
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Alicia D Zambrano
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Julio Inocencio
- The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Chirstopher D De Jesus
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Joseph O Louie
- The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Solen Gokhan
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Mark F Mehler
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA; Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, NY, USA; Ruth L. and David S. Gottesman Institute for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Center for Epigenomics, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Aging Research, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Aldrin E Molero
- Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, NY, USA; The Saul R. Korey Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, Bronx, NY, USA.
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165
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Huang WJ, Chen WW, Zhang X. Huntington's disease: Molecular basis of pathology and status of current therapeutic approaches. Exp Ther Med 2016; 12:1951-1956. [PMID: 27698679 PMCID: PMC5038571 DOI: 10.3892/etm.2016.3566] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/27/2016] [Indexed: 12/23/2022] Open
Abstract
Huntington's disease (HD) is a frequent and incurable hereditary neurodegenerative disorder that impairs motor and cognitive functions. Mutations in huntingtin (HTT) protein, which is essential for neuronal development, lead to the development of HD. An increase in the number of CAG repeats within the HTT gene, which lead to an expansion of polyglutamine tract in the resulting mutated HTT protein, which is toxic, is the causative factor of HD. Although the molecular basis of HD is known, there is no known cure for this disease other than symptomatic relief treatment approaches. The toxicity of mutHTT appears to be more detrimental to striatal medium spiny neurons, which degenerate in this disease. Therapeutic strategies addressing a reduction in the mutHTT content at the transcriptional level using zinc finger proteins and at the translational level with RNA interference and antisense oligonucleotides or promoting the proteosomal degradation of mutHTT are being studied extensively in preclinical models and also to a limited extent in clinical trials. The post-translational modification of mutHTT is another possibility that is currently being investigated for drug development. In addition to the pharmacological approaches, several lines of evidence suggested the potential therapeutic use of stem cell therapy, in particular using the patient-derived induced pluripotent stem cells, to replace the lost striatal neurons. The multi-pronged clinical investigations currently underway may identify therapies and potentially improve the quality of life for the HD patients in future.
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Affiliation(s)
- Wen-Juan Huang
- Department of Neurology, Xuzhou Central Hospital, Xuzhou, Jiangsu 221009, P.R. China
| | - Wei-Wei Chen
- Department of Neurology, Xuzhou Central Hospital, Xuzhou, Jiangsu 221009, P.R. China
| | - Xia Zhang
- Department of Neurology, Xuzhou Central Hospital, Xuzhou, Jiangsu 221009, P.R. China
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166
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Li L, Liu H, Dong P, Li D, Legant WR, Grimm JB, Lavis LD, Betzig E, Tjian R, Liu Z. Real-time imaging of Huntingtin aggregates diverting target search and gene transcription. eLife 2016; 5. [PMID: 27484239 PMCID: PMC4972539 DOI: 10.7554/elife.17056] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 07/07/2016] [Indexed: 01/21/2023] Open
Abstract
The presumptive altered dynamics of transient molecular interactions in vivo contributing to neurodegenerative diseases have remained elusive. Here, using single-molecule localization microscopy, we show that disease-inducing Huntingtin (mHtt) protein fragments display three distinct dynamic states in living cells - 1) fast diffusion, 2) dynamic clustering and 3) stable aggregation. Large, stable aggregates of mHtt exclude chromatin and form 'sticky' decoy traps that impede target search processes of key regulators involved in neurological disorders. Functional domain mapping based on super-resolution imaging reveals an unexpected role of aromatic amino acids in promoting protein-mHtt aggregate interactions. Genome-wide expression analysis and numerical simulation experiments suggest mHtt aggregates reduce transcription factor target site sampling frequency and impair critical gene expression programs in striatal neurons. Together, our results provide insights into how mHtt dynamically forms aggregates and disrupts the finely-balanced gene control mechanisms in neuronal cells.
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Affiliation(s)
- Li Li
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States.,LKS Bio-medical and Health Sciences Center, CIRM Center of Excellence, University of California, Berkeley, United States
| | - Hui Liu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Peng Dong
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Dong Li
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Wesley R Legant
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Jonathan B Grimm
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Luke D Lavis
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States.,Transcription Imaging Consortium, Howard Hughes Medical Institute, Ashburn, United States
| | - Eric Betzig
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Robert Tjian
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States.,LKS Bio-medical and Health Sciences Center, CIRM Center of Excellence, University of California, Berkeley, United States.,Transcription Imaging Consortium, Howard Hughes Medical Institute, Ashburn, United States
| | - Zhe Liu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States.,Transcription Imaging Consortium, Howard Hughes Medical Institute, Ashburn, United States
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167
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Fang B, Zhang M, Fan X, Ren F. The targeted proteins in tumor cells treated with the α-lactalbumin–oleic acid complex examined by descriptive and quantitative liquid chromatography–tandem mass spectrometry. J Dairy Sci 2016; 99:5991-6004. [DOI: 10.3168/jds.2016-10971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/14/2016] [Indexed: 01/26/2023]
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168
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Abstract
Polyglutamine (polyQ) expansion within Huntingtin (Htt) causes the fatal neurodegenerative disorder Huntington’s Disease (HD). Although Htt is ubiquitously expressed and conserved from Drosophila to humans, its normal biological function is still being elucidated. Here we characterize a role for the Drosophila Htt homolog (dHtt) in fast axonal transport (FAT). Generation and expression of transgenic dHtt-mRFP and human Htt-mRFP fusion proteins in Drosophila revealed co-localization with mitochondria and synaptic vesicles undergoing FAT. However, Htt was not ubiquitously associated with the transport machinery, as it was excluded from dense-core vesicles and APLIP1 containing vesicles. Quantification of cargo movement in dHtt deficient axons revealed that mitochondria and synaptic vesicles show a decrease in the distance and duration of transport, and an increase in the number of pauses. In addition, the ratio of retrograde to anterograde flux was increased in mutant animals. Densecore vesicles did not display similar defects in processivity, but did show altered retrograde to anterograde flux along axons. Given the co-localization with mitochondria and synaptic vesicles, but not dense-core vesicles, the data suggest dHtt likely acts locally at cargo interaction sites to regulate processivity. An increase in dynein heavy chain expression was also observed in dHtt mutants, suggesting that the altered flux observed for all cargo may represent secondary transport changes occurring independent of dHtt’s primary function. Expression of dHtt in a milton (HAP1) mutant background revealed that the protein does not require mitochondria or HAP1 to localize along axons, suggesting Htt has an independent mechanism for coupling with motors to regulate their processivity during axonal transport.
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Affiliation(s)
- Kurt R Weiss
- a Department of Biology , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA.,b Department of Brain and Cognitive Sciences , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA
| | - J Troy Littleton
- a Department of Biology , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA.,b Department of Brain and Cognitive Sciences , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA
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169
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Estévez-Fraga C, Avilés Olmos I, Mañanes Barral V, López-Sendón Moreno JL. Therapeutic advances in Huntington’s disease. Expert Opin Orphan Drugs 2016. [DOI: 10.1080/21678707.2016.1196128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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170
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N-terminal Huntingtin Knock-In Mice: Implications of Removing the N-terminal Region of Huntingtin for Therapy. PLoS Genet 2016; 12:e1006083. [PMID: 27203582 PMCID: PMC4874551 DOI: 10.1371/journal.pgen.1006083] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/04/2016] [Indexed: 02/07/2023] Open
Abstract
The Huntington’s disease (HD) protein, huntingtin (HTT), is a large protein consisting of 3144 amino acids and has conserved N-terminal sequences that are followed by a polyglutamine (polyQ) repeat. Loss of Htt is known to cause embryonic lethality in mice, whereas polyQ expansion leads to adult neuronal degeneration. Whether N-terminal HTT is essential for neuronal development or contributes only to late-onset neurodegeneration remains unknown. We established HTT knock-in mice (N160Q-KI) expressing the first 208 amino acids of HTT with 160Q, and they show age-dependent HTT aggregates in the brain and neurological phenotypes. Importantly, the N-terminal mutant HTT also preferentially accumulates in the striatum, the brain region most affected in HD, indicating the importance of N-terminal HTT in selective neuropathology. That said, homozygous N160Q-KI mice are also embryonic lethal, suggesting that N-terminal HTT alone is unable to support embryonic development. Using Htt knockout neurons, we found that loss of Htt selectively affects the survival of developing neuronal cells, but not astrocytes, in culture. This neuronal degeneration could be rescued by a truncated HTT lacking the first 237 amino acids, but not by N-terminal HTT (1–208 amino acids). Also, the rescue effect depends on the region in HTT known to be involved in intracellular trafficking. Thus, the N-terminal HTT region may not be essential for the survival of developing neurons, but when carrying a large polyQ repeat, can cause selective neuropathology. These findings imply a possible therapeutic benefit of removing the N-terminal region of HTT containing the polyQ repeat to treat the neurodegeneration in HD. The 17 amino acids in the N-terminal region of huntingtin (HTT) are conserved in a wide range of species and are followed by a polyglutamine repeat whose expansion causes selective neurodegeneration in Huntington’s disease (HD). Loss of Htt can affect developing neurons and early embryonic development in mice. Whether N-terminal HTT is important for the survival of developing neurons or contributes mainly to a gain of toxic function in HD remains unknown. In the current study, we generated N-terminal mutant HTT knock-in mice and found that N-terminal HTT with an expanded polyQ repeat is unable to support the early development of mice, but can cause age-dependent neurological phenotypes. Further, we show that a truncated HTT without the N-terminal region can rescue the Htt loss-mediated degeneration of developing neurons. Our studies suggest that removal of the N-terminal region of mutant HTT could be a strategy to abolish the neuronal toxicity of mutant HTT.
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171
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Vidoni C, Follo C, Savino M, Melone MAB, Isidoro C. The Role of Cathepsin D in the Pathogenesis of Human Neurodegenerative Disorders. Med Res Rev 2016; 36:845-70. [DOI: 10.1002/med.21394] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 03/29/2016] [Accepted: 03/29/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Chiara Vidoni
- Laboratory of Molecular Pathology, Department of Health Sciences; Università del Piemonte Orientale “A. Avogadro,”; Novara Italy
| | - Carlo Follo
- Laboratory of Molecular Pathology, Department of Health Sciences; Università del Piemonte Orientale “A. Avogadro,”; Novara Italy
| | - Miriam Savino
- Laboratory of Molecular Pathology, Department of Health Sciences; Università del Piemonte Orientale “A. Avogadro,”; Novara Italy
| | - Mariarosa A. B. Melone
- Division of Neurology, Department of Clinic and Experimental Medicine and Surgery; Second University of Naples; Naples Italy
- InterUniversity Center for Research in Neurosciences; Second University of Naples; Naples Italy
| | - Ciro Isidoro
- Laboratory of Molecular Pathology, Department of Health Sciences; Università del Piemonte Orientale “A. Avogadro,”; Novara Italy
- InterUniversity Center for Research in Neurosciences; Second University of Naples; Naples Italy
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172
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Ablation of huntingtin in adult neurons is nondeleterious but its depletion in young mice causes acute pancreatitis. Proc Natl Acad Sci U S A 2016; 113:3359-64. [PMID: 26951659 DOI: 10.1073/pnas.1524575113] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The Huntington's disease (HD) protein, huntingtin (HTT), is essential for early development. Because suppressing the expression of mutant HTT is an important approach to treat the disease, we must first understand the normal function of Htt in adults versus younger animals. Using inducible Htt knockout mice, we found that Htt depletion does not lead to adult neurodegeneration or animal death at >4 mo of age, which was also verified by selectively depleting Htt in neurons. On the other hand, young Htt KO mice die at 2 mo of age of acute pancreatitis due to the degeneration of pancreatic acinar cells. Importantly, Htt interacts with the trypsin inhibitor, serine protease inhibitor Kazal-type 3 (Spink3), to inhibit activation of digestive enzymes in acinar cells in young mice, and transgenic HTT can rescue the early death of Htt KO mice. These findings point out age- and cell type-dependent vital functions of Htt and the safety of knocking down neuronal Htt expression in adult brains as a treatment.
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173
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174
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Sarantos MR, Papanikolaou T, Ellerby LM, Hughes RE. Pizotifen Activates ERK and Provides Neuroprotection in vitro and in vivo in Models of Huntington's Disease. J Huntingtons Dis 2016; 1:195-210. [PMID: 23393546 DOI: 10.3233/jhd-120033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Huntington's disease (HD) is a dominantly inherited neurodegenerative condition characterized by dysfunction in striatal and cortical neurons. There are currently no approved drugs known to slow the progression of HD. OBJECTIVE To facilitate the development of therapies for HD, we identified approved drugs that can ameliorate mutant huntingtin-induced toxicity in experimental models of HD. METHODS A chemical screen was performed in a mouse Hdh(Q111/Q111) striatal cell model of HD. This screen identified a set of structurally related approved drugs (pizotifen, cyproheptadine, and loxapine) that rescued cell death in this model. Pizotifen was subsequently evaluated in the R6/2 HD mouse model. RESULTS We found that in striatal Hdh(Q111/Q111) cells, pizotifen treatment caused transient ERK activation and inhibition of ERK activation prevented rescue of cell death in this model. In the R6/2 HD mouse model, treatment with pizotifen activated ERK in the striatum, reduced neurodegeneration and significantly enhanced motor performance. CONCLUSIONS These results suggest that pizotifen and related approved drugs may provide a basis for developing disease modifying therapeutic interventions for HD.
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175
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Fisher SP, Schwartz MD, Wurts-Black S, Thomas AM, Chen TM, Miller MA, Palmerston JB, Kilduff TS, Morairty SR. Quantitative Electroencephalographic Analysis Provides an Early-Stage Indicator of Disease Onset and Progression in the zQ175 Knock-In Mouse Model of Huntington's Disease. Sleep 2016; 39:379-91. [PMID: 26446107 DOI: 10.5665/sleep.5448] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 09/05/2015] [Indexed: 01/09/2023] Open
Abstract
STUDY OBJECTIVES Patients with Huntington's disease (HD) show a high prevalence of sleep disorders that typically occur prior to the onset of motoric symptoms and neurodegeneration. Our understanding of the pathophysiological alterations in premanifest HD is limited, hindering the ability to measure disease modification in response to treatment. We used a full-length knock-in HD model to determine early changes in the electroencephalogram (EEG) and sleep that may predict the onset and progression of the disease. METHODS A 10-month longitudinal study was designed to determine the effect of the HD mutation on the EEG and sleep/wake changes in heterozygous (HET) and homozygous (HOM) zQ175 mice and wild-type (WT) littermates from 8 to 48 w of age. Mice were instrumented with tethered headmounts to record EEG/electromyography signals. Telemeters were implanted to continuously measure locomotor activity (LMA) and body temperature (Tb). Sleep deprivation (SDep) was performed at 8, 12, 16, 24, 32, and 48 w of age. RESULTS The HD mutation disrupted the EEG field potential from 8-12 w in an age- and mutant huntington dose-dependent manner, prior to changes in sleep/wake states, LMA, and Tb. Prominent effects of the HD mutation on the EEG included a progressive reduction in low frequency power, a slowing of rapid eye movement peak theta frequency, and the emergence of state-dependent beta/gamma oscillations. There was no effect of genotype on the relative increase in nonrapid eye movement delta power or sleep time in response to SDep. CONCLUSIONS The expression of the Huntington's disease (HD) mutation results in complex EEG alterations that occur prior to deficits in behavioral measures and are one of the earliest phenotypes uncovered in this mouse model. Despite these EEG changes, homeostatic responses to sleep loss were preserved in HET and HOM zQ175 mice. Greater insight into the localization and response of these EEG alterations to novel therapies may enable early intervention and improve outcomes for patients with HD.
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Affiliation(s)
- Simon P Fisher
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Michael D Schwartz
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Sarah Wurts-Black
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Alexia M Thomas
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Tsui-Ming Chen
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Michael A Miller
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Jeremiah B Palmerston
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Thomas S Kilduff
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
| | - Stephen R Morairty
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, California
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176
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Golas MM, Sander B. Use of human stem cells in Huntington disease modeling and translational research. Exp Neurol 2016; 278:76-90. [PMID: 26826449 DOI: 10.1016/j.expneurol.2016.01.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 01/22/2016] [Accepted: 01/25/2016] [Indexed: 02/08/2023]
Abstract
Huntington disease (HD) is a devastating neurological disorder caused by an extended CAG repeat in exon 1 of the gene that encodes the huntingtin (HTT) protein. HD pathology involves a loss of striatal medium spiny neurons (MSNs) and progressive neurodegeneration affects the striatum and other brain regions. Because HTT is involved in multiple cellular processes, the molecular mechanisms of HD pathogenesis should be investigated on multiple levels. On the cellular level, in vitro stem cell models, such as induced pluripotent stem cells (iPSCs) derived from HD patients and HD embryonic stem cells (ESCs), have yielded progress. Approaches to differentiate functional MSNs from ESCs, iPSCs, and neural stem/progenitor cells (NSCs/NPCs) have been established, enabling MSN differentiation to be studied and disease phenotypes to be recapitulated. Isolation of target stem cells and precursor cells may also provide a resource for grafting. In animal models, transplantation of striatal precursors differentiated in vitro to the striatum has been reported to improve disease phenotype. Initial clinical trials examining intrastriatal transplantation of fetal neural tissue suggest a more favorable clinical course in a subset of HD patients, though shortcomings persist. Here, we review recent advances in the development of cellular HD models and approaches aimed at cell regeneration with human stem cells. We also describe how genome editing tools could be used to correct the HTT mutation in patient-specific stem cells. Finally, we discuss the potential and the remaining challenges of stem cell-based approaches in HD research and therapy development.
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Affiliation(s)
- Monika M Golas
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark.
| | - Bjoern Sander
- Stereology and Electron Microscopy Laboratory, Department of Clinical Medicine, Aarhus University, Aarhus C, Denmark
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177
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Kerschbamer E, Biagioli M. Huntington's Disease as Neurodevelopmental Disorder: Altered Chromatin Regulation, Coding, and Non-Coding RNA Transcription. Front Neurosci 2016; 9:509. [PMID: 26793052 PMCID: PMC4710752 DOI: 10.3389/fnins.2015.00509] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 12/21/2015] [Indexed: 01/05/2023] Open
Affiliation(s)
- Emanuela Kerschbamer
- NeuroEpigenetics Laboratory, Centre for Integrative Biology, University of Trento Trento, Italy
| | - Marta Biagioli
- NeuroEpigenetics Laboratory, Centre for Integrative Biology, University of Trento Trento, Italy
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178
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Abstract
Huntington disease (HD) is caused by the CAG (Q) expansion in exon 1 of the IT15 gene encoding a polyglutamine (poly-Q) stretch of the Huntingtin protein (Htt). In the wild type protein, the repeats specify a stretch of up 34 Q in the N-terminal portion of Htt. In the pathological protein (mHtt) the poly-Q tract is longer. Proteolytic cleavage of the protein liberates an N-terminal fragment containing the expanded poly-Q tract becomes harmful to cells, in particular to striatal neurons. The fragments cause the transcriptional dysfunction of genes that are essential for neuronal survival. Htt, however, could also have non-transcriptional effects, e.g. it could directly alter Ca2+ homeostasis and/or mitochondrial morphology and function. Ca2+ dyshomeostasis and mitochondrial dysfunction are considered important in the molecular aetiology of the disease. Here we have analyzed the effect of the overexpression of Htt fragments (18Q, wild type form, wtHtt and 150Q mutated form, mHtt) on Ca2+ homeostasis in striatal neuronal precursor cells (Q7/7). We have found that the transient overexpression of the Htt fragments increases Ca2+ transients in the mitochondria of cells stimulated with Ca2+-mobilizing agonists. The bulk Ca2+ transients in the cytosol were unaffected, but the Ca2+ content of the endoplasmic reticulum was significantly decreased in the case of mHtt expression. To rule out possible transcriptional effects due to the presence of mHtt, we have measured the mRNA level of a subunit of the respiratory chain complex II, whose expression is commonly altered in many HD models. No effects on the mRNA level was found suggesting that, in our experimental condition, transcriptional action of Htt is not occurring and that the effects on Ca2+ homeostasis were dependent to non-transcriptional mechanisms.
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179
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Wojciechowski M, Gómez-Sicilia À, Carrión-Vázquez M, Cieplak M. Unfolding knots by proteasome-like systems: simulations of the behaviour of folded and neurotoxic proteins. MOLECULAR BIOSYSTEMS 2016; 12:2700-12. [DOI: 10.1039/c6mb00214e] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Knots in proteins have been proposed to resist proteasomal degradation, thought in turn to be related to neurodegenerative diseases such as Huntington.
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Affiliation(s)
| | - Àngel Gómez-Sicilia
- Instituto Cajal
- Consejo Superior de Investigaciones Científicas
- (CSIC)
- 28002 Madrid
- Spain
| | | | - Marek Cieplak
- Institute of Physics
- Polish Academy of Sciences
- PL-02668 Warsaw
- Poland
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180
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Sethi R, Patel V, Saleh AA, Roy I. Cellular toxicity of yeast prion protein Rnq1 can be modulated by N-terminal wild type huntingtin. Arch Biochem Biophys 2016; 590:82-89. [DOI: 10.1016/j.abb.2015.11.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 11/20/2015] [Accepted: 11/21/2015] [Indexed: 01/07/2023]
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181
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Kerkis I, Haddad MS, Valverde CW, Glosman S. Neural and mesenchymal stem cells in animal models of Huntington's disease: past experiences and future challenges. Stem Cell Res Ther 2015; 6:232. [PMID: 26667114 PMCID: PMC4678723 DOI: 10.1186/s13287-015-0248-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Huntington's disease (HD) is an inherited disease that causes progressive nerve cell degeneration. It is triggered by a mutation in the HTT gene that strongly influences functional abilities and usually results in movement, cognitive and psychiatric disorders. HD is incurable, although treatments are available to help manage symptoms and to delay the physical, mental and behavioral declines associated with the condition. Stem cells are the essential building blocks of life, and play a crucial role in the genesis and development of all higher organisms. Ablative surgical procedures and fetal tissue cell transplantation, which are still experimental, demonstrate low rates of recovery in HD patients. Due to neuronal cell death caused by accumulation of the mutated huntingtin (mHTT) protein, it is unlikely that such brain damage can be treated solely by drug-based therapies. Stem cell-based therapies are important in order to reconstruct damaged brain areas in HD patients. These therapies have a dual role: stem cell paracrine action, stimulating local cell survival, and brain tissue regeneration through the production of new neurons from the intrinsic and likely from donor stem cells. This review summarizes current knowledge on neural stem/progenitor cell and mesenchymal stem cell transplantation, which has been carried out in several animal models of HD, discussing cell distribution, survival and differentiation after transplantation, as well as functional recovery and anatomic improvements associated with these approaches. We also discuss the usefulness of this information for future preclinical and clinical studies in HD.
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Affiliation(s)
- Irina Kerkis
- Laboratório de Genética, Instituto Butantan, 1500 Av. Vital Brasil, São Paulo, 05503-900, Brazil.
| | - Monica Santoro Haddad
- Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, 455 Av. Dr. Arnaldao, São Paulo, 01246903, Brazil
| | | | - Sabina Glosman
- SoluBest Ltd, Weizmann Science Park, POB 4053 18 Einstein Street, Ness Ziona, 74140, Israel
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182
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Yan J, Zhang H, Liu Y, Zhao F, Zhu S, Xie C, Tang TS, Guo C. Germline deletion of huntingtin causes male infertility and arrested spermiogenesis in mice. J Cell Sci 2015; 129:492-501. [PMID: 26659666 DOI: 10.1242/jcs.173666] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 12/07/2015] [Indexed: 01/28/2023] Open
Abstract
Human Huntingtin (HTT), a Huntington's disease gene, is highly expressed in the mammalian brain and testis. Simultaneous knockout of mouse Huntingtin (Htt) in brain and testis impairs male fertility, providing evidence for a link between Htt and spermatogenesis; however, the underlying mechanism remains unclear. To understand better the function of Htt in spermatogenesis, we restricted the genetic deletion specifically to the germ cells using the Cre/loxP site-specific recombination strategy and found that the resulting mice manifested smaller testes, azoospermia and complete male infertility. Meiotic chromosome spread experiments showed that the process of meiosis was normal in the absence of Htt. Notably, we found that Htt-deficient round spermatids did not progress beyond step 3 during the post-meiotic phase, when round spermatids differentiate into mature spermatozoa. Using an iTRAQ-based quantitative proteomic assay, we found that knockout of Htt significantly altered the testis protein profile. The differentially expressed proteins exhibited a remarkable enrichment for proteins involved in translation regulation and DNA packaging, suggesting that Htt might play a role in spermatogenesis by regulating translation and DNA packaging in the testis.
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Affiliation(s)
- Jinting Yan
- CAS Key Laboratory of Genomic and Precision Medicine, China Gastrointestinal Cancer Research Center, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Hui Zhang
- CAS Key Laboratory of Genomic and Precision Medicine, China Gastrointestinal Cancer Research Center, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yang Liu
- CAS Key Laboratory of Genomic and Precision Medicine, China Gastrointestinal Cancer Research Center, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Feilong Zhao
- CAS Key Laboratory of Genomic and Precision Medicine, China Gastrointestinal Cancer Research Center, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Shu Zhu
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Chengmei Xie
- CAS Key Laboratory of Genomic and Precision Medicine, China Gastrointestinal Cancer Research Center, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Tie-Shan Tang
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Caixia Guo
- CAS Key Laboratory of Genomic and Precision Medicine, China Gastrointestinal Cancer Research Center, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
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Liu L, Huang JS, Han C, Zhang GX, Xu XY, Shen Y, Li J, Jiang HY, Lin ZC, Xiong N, Wang T. Induced Pluripotent Stem Cells in Huntington's Disease: Disease Modeling and the Potential for Cell-Based Therapy. Mol Neurobiol 2015; 53:6698-6708. [PMID: 26659595 DOI: 10.1007/s12035-015-9601-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 12/01/2015] [Indexed: 12/31/2022]
Abstract
Huntington's disease (HD) is an incurable neurodegenerative disorder that is characterized by motor dysfunction, cognitive impairment, and behavioral abnormalities. It is an autosomal dominant disorder caused by a CAG repeat expansion in the huntingtin gene, resulting in progressive neuronal loss predominately in the striatum and cortex. Despite the discovery of the causative gene in 1993, the exact mechanisms underlying HD pathogenesis have yet to be elucidated. Treatments that slow or halt the disease process are currently unavailable. Recent advances in induced pluripotent stem cell (iPSC) technologies have transformed our ability to study disease in human neural cells. Here, we firstly review the progress made to model HD in vitro using patient-derived iPSCs, which reveal unique insights into illuminating molecular mechanisms and provide a novel human cell-based platform for drug discovery. We then highlight the promises and challenges for pluripotent stem cells that might be used as a therapeutic source for cell replacement therapy of the lost neurons in HD brains.
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Affiliation(s)
- Ling Liu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jin-Sha Huang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Chao Han
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Guo-Xin Zhang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiao-Yun Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yan Shen
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jie Li
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hai-Yang Jiang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhi-Cheng Lin
- Department of Psychiatry, Harvard Medical School; Division of Alcohol and Drug Abuse, and Mailman Neuroscience Research Center, McLean Hospital, Belmont, MA, USA
| | - Nian Xiong
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Tao Wang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
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184
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Veldman MB, Rios-Galdamez Y, Lu XH, Gu X, Qin W, Li S, Yang XW, Lin S. The N17 domain mitigates nuclear toxicity in a novel zebrafish Huntington's disease model. Mol Neurodegener 2015; 10:67. [PMID: 26645399 PMCID: PMC4673728 DOI: 10.1186/s13024-015-0063-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 11/30/2015] [Indexed: 01/14/2023] Open
Abstract
Background Although the genetic cause for Huntington’s disease (HD) has been known for over 20 years, the mechanisms that cause the neurotoxicity and behavioral symptoms of this disease are not well understood. One hypothesis is that N-terminal fragments of the HTT protein are the causative agents in HD and that peptide sequences adjacent to the poly-glutamine (Q) repeats modify its toxicity. Here we test the function of the N-terminal 17 amino acids (N17) in the context of the exon 1 fragment of HTT in a novel, inducible zebrafish model of HD. Results Deletion of N17 coupled with 97Q expansion (mHTT-ΔN17-exon1) resulted in a robust, rapidly progressing movement deficit, while fish with intact N17 and 97Q expansion (mHTT-exon1) have more delayed-onset movement deficits with slower progression. The level of mHTT-ΔN17-exon1 protein was significantly higher than mHTT-exon1, although the mRNA level of each transgene was marginally different, suggesting that N17 may regulate HTT protein stability in vivo. In addition, cell lineage specific induction of the mHTT-ΔN17-exon1 transgene in neurons was sufficient to recapitulate the consequences of ubiquitous transgene expression. Within neurons, accelerated nuclear accumulation of the toxic HTT fragment was observed in mHTT-ΔN17-exon1 fish, demonstrating that N17 also plays an important role in sub-cellular localization in vivo. Conclusions We have developed a novel, inducible zebrafish model of HD. These animals exhibit a progressive movement deficit reminiscent of that seen in other animal models and human patients. Deletion of the N17 terminal amino acids of the huntingtin fragment results in an accelerated HD-like phenotype that may be due to enhanced protein stability and nuclear accumulation of HTT. These transgenic lines will provide a valuable new tool to study mechanisms of HD at the behavioral, cellular, and molecular levels. Future experiments will be focused on identifying genetic modifiers, mechanisms and therapeutics that alleviate polyQ aggregation in the nucleus of neurons. Electronic supplementary material The online version of this article (doi:10.1186/s13024-015-0063-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Matthew B Veldman
- Department of Molecular, Cell and Developmental Biology, University of California-Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - Yesenia Rios-Galdamez
- Department of Molecular, Cell and Developmental Biology, University of California-Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
| | - Xiao-Hong Lu
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, Los Angeles, USA.,Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, Los Angeles, USA.,Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Xiaofeng Gu
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, Los Angeles, USA.,Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, Los Angeles, USA.,Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Wei Qin
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Song Li
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - X William Yang
- Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, Los Angeles, USA.,Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, Los Angeles, USA.,Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Shuo Lin
- Department of Molecular, Cell and Developmental Biology, University of California-Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA, 90095, USA. .,Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China.
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185
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Holm IE, Alstrup AKO, Luo Y. Genetically modified pig models for neurodegenerative disorders. J Pathol 2015; 238:267-87. [DOI: 10.1002/path.4654] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/22/2015] [Accepted: 10/05/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Ida E Holm
- Department of Pathology; Randers Hospital; 8930 Randers Denmark
- Department of Clinical Medicine; Aarhus University; 8000 Aarhus C Denmark
| | | | - Yonglun Luo
- Department of Biomedicine; Aarhus University; 8000 Aarhus C Denmark
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186
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The Function of Autophagy in Neurodegenerative Diseases. Int J Mol Sci 2015; 16:26797-812. [PMID: 26569220 PMCID: PMC4661849 DOI: 10.3390/ijms161125990] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 10/30/2015] [Accepted: 11/02/2015] [Indexed: 12/11/2022] Open
Abstract
Macroautophagy, hereafter referred to as autophagy, is a bulk degradation process performed by lysosomes in which aggregated and altered proteins as well as dysfunctional organelles are decomposed. Autophagy is a basic cellular process that maintains homeostasis and is crucial for postmitotic neurons. Thus, impaired autophagic processes in neurons lead to improper homeostasis and neurodegeneration. Recent studies have suggested that impairments of the autophagic process are associated with several neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and static encephalopathy of childhood with neurodegeneration in adulthood. In this review, we focus on the recent findings regarding the autophagic process and the involvement of autophagy in neurodegenerative diseases.
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187
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Gómez-Sicilia À, Sikora M, Cieplak M, Carrión-Vázquez M. An Exploration of the Universe of Polyglutamine Structures. PLoS Comput Biol 2015; 11:e1004541. [PMID: 26495838 PMCID: PMC4619799 DOI: 10.1371/journal.pcbi.1004541] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 09/08/2015] [Indexed: 12/02/2022] Open
Abstract
Deposits of misfolded proteins in the human brain are associated with the development of many neurodegenerative diseases. Recent studies show that these proteins have common traits even at the monomer level. Among them, a polyglutamine region that is present in huntingtin is known to exhibit a correlation between the length of the chain and the severity as well as the earliness of the onset of Huntington disease. Here, we apply bias exchange molecular dynamics to generate structures of polyglutamine expansions of several lengths and characterize the resulting independent conformations. We compare the properties of these conformations to those of the standard proteins, as well as to other homopolymeric tracts. We find that, similar to the previously studied polyvaline chains, the set of possible transient folds is much broader than the set of known-to-date folds, although the conformations have different structures. We show that the mechanical stability is not related to any simple geometrical characteristics of the structures. We demonstrate that long polyglutamine expansions result in higher mechanical stability than the shorter ones. They also have a longer life span and are substantially more prone to form knotted structures. The knotted region has an average length of 35 residues, similar to the typical threshold for most polyglutamine-related diseases. Similarly, changes in shape and mechanical stability appear once the total length of the peptide exceeds this threshold of 35 glutamine residues. We suggest that knotted conformers may also harm the cellular machinery and thus lead to disease. Misfolding and aggregation of several proteins are known to be related to neurodegenerative diseases. Among them, polyglutamine expansions are known to be responsible for at least 9 diseases, including Huntington. Nonetheless, the structural properties of these intrinsically disordered proteins are difficult to study using classical techniques because of their rapid fluctuations that result in high conformational polymorphism. Here, we use molecular dynamics simulations to study polyglutamines of different chain lengths, starting with short non-pathogenic ones, and study the independent structures they are able to form. We characterize all structures by their geometrical properties, connectivity, putative mechanical stability and residence time (life span). Similar to the findings of a previous study with polyvalines, only some of the conformers are similar to those found in natural globular proteins. Moreover, we find structures that contain knots in both polyglutamine and polyvaline 60-mers, although the former contains many more knotted conformers than the latter. We suggest that these knotted conformers may impair the cell machinery for degradation and eventually lead to toxicity.
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Affiliation(s)
- Àngel Gómez-Sicilia
- Intituto Cajal/CSIC, Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia),Madrid, Spain
| | - Mateusz Sikora
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | | | - Mariano Carrión-Vázquez
- Intituto Cajal/CSIC, Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia),Madrid, Spain
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188
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Clemens LE, Weber JJ, Wlodkowski TT, Yu-Taeger L, Michaud M, Calaminus C, Eckert SH, Gaca J, Weiss A, Magg JCD, Jansson EKH, Eckert GP, Pichler BJ, Bordet T, Pruss RM, Riess O, Nguyen HP. Olesoxime suppresses calpain activation and mutant huntingtin fragmentation in the BACHD rat. Brain 2015; 138:3632-53. [PMID: 26490331 DOI: 10.1093/brain/awv290] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 08/11/2015] [Indexed: 12/14/2022] Open
Abstract
Huntington's disease is a fatal human neurodegenerative disorder caused by a CAG repeat expansion in the HTT gene, which translates into a mutant huntingtin protein. A key event in the molecular pathogenesis of Huntington's disease is the proteolytic cleavage of mutant huntingtin, leading to the accumulation of toxic protein fragments. Mutant huntingtin cleavage has been linked to the overactivation of proteases due to mitochondrial dysfunction and calcium derangements. Here, we investigated the therapeutic potential of olesoxime, a mitochondria-targeting, neuroprotective compound, in the BACHD rat model of Huntington's disease. BACHD rats were treated with olesoxime via the food for 12 months. In vivo analysis covered motor impairments, cognitive deficits, mood disturbances and brain atrophy. Ex vivo analyses addressed olesoxime's effect on mutant huntingtin aggregation and cleavage, as well as brain mitochondria function. Olesoxime improved cognitive and psychiatric phenotypes, and ameliorated cortical thinning in the BACHD rat. The treatment reduced cerebral mutant huntingtin aggregates and nuclear accumulation. Further analysis revealed a cortex-specific overactivation of calpain in untreated BACHD rats. Treated BACHD rats instead showed significantly reduced levels of mutant huntingtin fragments due to the suppression of calpain-mediated cleavage. In addition, olesoxime reduced the amount of mutant huntingtin fragments associated with mitochondria, restored a respiration deficit, and enhanced the expression of fusion and outer-membrane transport proteins. In conclusion, we discovered the calpain proteolytic system, a key player in Huntington's disease and other neurodegenerative disorders, as a target of olesoxime. Our findings suggest that olesoxime exerts its beneficial effects by improving mitochondrial function, which results in reduced calpain activation. The observed alleviation of behavioural and neuropathological phenotypes encourages further investigations on the use of olesoxime as a therapeutic for Huntington's disease.
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Affiliation(s)
- Laura E Clemens
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
| | - Jonasz J Weber
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
| | - Tanja T Wlodkowski
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
| | - Libo Yu-Taeger
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
| | - Magali Michaud
- 3 Trophos SA., Parc Scientifique de Luminy Case 931, 13288 Marseille Cedex 9, France
| | - Carsten Calaminus
- 4 Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, University of Tuebingen, Roentgenweg 13, 72076 Tuebingen, Germany
| | - Schamim H Eckert
- 5 Department of Pharmacology, Goethe University Frankfurt am Main, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Janett Gaca
- 5 Department of Pharmacology, Goethe University Frankfurt am Main, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Andreas Weiss
- 6 Novartis Institutes for BioMedical Research, Klybeckstrasse 141, 4057 Basel, Switzerland
| | - Janine C D Magg
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
| | - Erik K H Jansson
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
| | - Gunter P Eckert
- 5 Department of Pharmacology, Goethe University Frankfurt am Main, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Bernd J Pichler
- 4 Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, University of Tuebingen, Roentgenweg 13, 72076 Tuebingen, Germany
| | - Thierry Bordet
- 3 Trophos SA., Parc Scientifique de Luminy Case 931, 13288 Marseille Cedex 9, France
| | - Rebecca M Pruss
- 3 Trophos SA., Parc Scientifique de Luminy Case 931, 13288 Marseille Cedex 9, France
| | - Olaf Riess
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
| | - Huu P Nguyen
- 1 Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany 2 Centre for Rare Diseases, University of Tuebingen, Calwerstrasse 7, 72076 Tuebingen, Germany
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189
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White JA, Anderson E, Zimmerman K, Zheng KH, Rouhani R, Gunawardena S. Huntingtin differentially regulates the axonal transport of a sub-set of Rab-containing vesicles in vivo. Hum Mol Genet 2015; 24:7182-95. [PMID: 26450517 DOI: 10.1093/hmg/ddv415] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/28/2015] [Indexed: 11/14/2022] Open
Abstract
Loss of huntingtin (HTT), the Huntington's disease (HD) protein, was previously shown to cause axonal transport defects. Within axons, HTT can associate with kinesin-1 and dynein motors either directly or via accessory proteins for bi-directional movement. However, the composition of the vesicle-motor complex that contains HTT during axonal transport is unknown. Here we analyze the in vivo movement of 16 Rab GTPases within Drosophila larval axons and show that HTT differentially influences the movement of a particular sub-set of these Rab-containing vesicles. While reduction of HTT perturbed the bi-directional motility of Rab3 and Rab19-containing vesicles, only the retrograde motility of Rab7-containing vesicles was disrupted with reduction of HTT. Interestingly, reduction of HTT stimulated the anterograde motility of Rab2-containing vesicles. Simultaneous dual-view imaging revealed that HTT and Rab2, 7 or 19 move together during axonal transport. Collectively, our findings indicate that HTT likely influences the motility of different Rab-containing vesicles and Rab-mediated functions. These findings have important implications for our understanding of the complex role HTT plays within neurons normally, which when disrupted may lead to neuronal death and disease.
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Affiliation(s)
- Joseph A White
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Eric Anderson
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Katherine Zimmerman
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Kan Hong Zheng
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Roza Rouhani
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Shermali Gunawardena
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
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190
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Abstract
Polyglutamine (polyQ) diseases are heritable dominant neurological disorders, caused by abnormal CAG tri-nucleotide expansion in the coding sequence of affected genes. Extension of CAG repeats results in the production of aberrant gene products that are deleterious to neurons, such as transcripts with a CAG stem-loop secondary structure, and proteins containing a long stretch of polyQ residues. Thus, determining methods for the prevention or elimination of these mutant gene products from neuronal cells and translating this knowledge to clinical application are currently important goals in the fields of neurology and neurogenetics. Recently, several studies have revealed intriguing findings related to the allele-selective regulation of CAG-expanded genes, and have proposed novel designs to selectively diminish the mutant polyQ proteins. In this review, we focus on the genes, genetically engineered proteins, and oligonucleotides that show potential to modulate the expression of mutant genes. We also discuss their respective molecular functions at the levels of transcription, translation, and post-translation.
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Affiliation(s)
- Chia-Rung Liu
- a Institute of Biochemistry and Molecular Biology, National Yang-Ming University , Taipei , Taiwan , Republic of China
| | - Tzu-Hao Cheng
- a Institute of Biochemistry and Molecular Biology, National Yang-Ming University , Taipei , Taiwan , Republic of China.,b Brain Research Center, National Yang-Ming University , Taipei , Taiwan , Republic of China
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191
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Sharma S, Taliyan R. Transcriptional dysregulation in Huntington's disease: The role of histone deacetylases. Pharmacol Res 2015; 100:157-69. [PMID: 26254871 DOI: 10.1016/j.phrs.2015.08.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 08/03/2015] [Accepted: 08/03/2015] [Indexed: 12/16/2022]
Abstract
Huntington's disease (HD) is a progressive neurological disorder for which there are no disease-modifying treatments. Although, the exact underlying mechanism(s) leading to the neural cell death in HD still remains elusive, the transcriptional dysregulation is a major molecular feature. Recently, the transcriptional activation and repression regulated by chromatin acetylation has been found to be impaired in HD pathology. The acetylation and deacetylation of histone proteins is carried out by opposing actions of histone acetyl-transferases and histone deacetylases (HDACs), respectively. Studies carried out in cell culture, yeast, Drosophila and rodent model(s) have indicated that HDAC inhibitors (HDACIs) might provide useful class of therapeutic agents for HD. Clinical trials have also reported the beneficial effects of HDACIs in patients suffering from HD. Therefore, the development of HDACIs as therapeutics for HD has been vigorously pursued. In this review, we highlight and summarize the putative role of HDACs in HD like pathology and further discuss the potential of HDACIs as new therapeutic avenues for the treatment of HD.
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Affiliation(s)
- Sorabh Sharma
- Neuropharmacology Division, Department of Pharmacy Birla Institute of Technology and Science, Pilani 333031, Rajasthan, India.
| | - Rajeev Taliyan
- Neuropharmacology Division, Department of Pharmacy Birla Institute of Technology and Science, Pilani 333031, Rajasthan, India
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192
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Xu Z, Tito AJ, Rui YN, Zhang S. Studying polyglutamine diseases in Drosophila. Exp Neurol 2015; 274:25-41. [PMID: 26257024 DOI: 10.1016/j.expneurol.2015.08.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 08/02/2015] [Accepted: 08/03/2015] [Indexed: 12/16/2022]
Abstract
Polyglutamine (polyQ) diseases are a family of dominantly transmitted neurodegenerative disorders caused by an abnormal expansion of CAG trinucleotide repeats in the protein-coding regions of the respective disease-causing genes. Despite their simple genetic basis, the etiology of these diseases is far from clear. Over the past two decades, Drosophila has proven to be successful in modeling this family of neurodegenerative disorders, including the faithful recapitulation of pathological features such as polyQ length-dependent formation of protein aggregates and progressive neuronal degeneration. Additionally, it has been valuable in probing the pathogenic mechanisms, in identifying and evaluating disease modifiers, and in helping elucidate the normal functions of disease-causing genes. Knowledge learned from this simple invertebrate organism has had a large impact on our understanding of these devastating brain diseases.
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Affiliation(s)
- Zhen Xu
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States
| | - Antonio Joel Tito
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; Programs in Human and Molecular Genetics and Neuroscience, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Graduate School of Biomedical Sciences, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States
| | - Yan-Ning Rui
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States
| | - Sheng Zhang
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; Department of Neurobiology and Anatomy, 1825 Pressler Street, Houston, TX 77030, United States; Programs in Human and Molecular Genetics and Neuroscience, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Graduate School of Biomedical Sciences, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States.
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193
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Srivastava D, Chakrabarti O. Ubiquitin in regulation of spindle apparatus and its positioning: implications in development and disease. Biochem Cell Biol 2015; 93:273-81. [PMID: 26110206 DOI: 10.1139/bcb-2015-0011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Emerging data implicates ubiquitination, a post-translational modification, in regulating essential cellular events, one of them being mitosis. In this review we discuss how various E3 ligases modulate the cortical proteins such as dynein, LGN, NuMa, Gα, along with polymerization, stability, and integrity of spindles. These are responsible for regulating symmetric cell division. Some of the ubiquitin ligases regulating these proteins include PARK2, BRCA1/BARD1, MGRN1, SMURF2, and SIAH1; these play a pivotal role in the correct positioning of the spindle apparatus. A direct connection between developmental or various pathological disorders and the ubiquitination mediated cortical regulation is rather speculative, though deletions or mutations in them lead to developmental disorders and disease conditions.
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Affiliation(s)
- Devika Srivastava
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Sector-1, Block-AF, Bidhannagar, Kolkata, West Bengal 700064, India
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Sector-1, Block-AF, Bidhannagar, Kolkata, West Bengal 700064, India
| | - Oishee Chakrabarti
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Sector-1, Block-AF, Bidhannagar, Kolkata, West Bengal 700064, India
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Sector-1, Block-AF, Bidhannagar, Kolkata, West Bengal 700064, India
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194
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Bellone JA, Rudobeck E, Hartman RE, Szücs A, Vlkolinský R. A Single Low Dose of Proton Radiation Induces Long-Term Behavioral and Electrophysiological Changes in Mice. Radiat Res 2015. [DOI: 10.1667/rr13903.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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195
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Shannon KM, Fraint A. Therapeutic advances in Huntington's Disease. Mov Disord 2015; 30:1539-46. [DOI: 10.1002/mds.26331] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 06/15/2015] [Indexed: 01/09/2023] Open
Affiliation(s)
- Kathleen M. Shannon
- Department of Neurological Sciences; Rush Medical College; Chicago Illinois USA
| | - Avram Fraint
- Department of Neurological Sciences; Rush Medical College; Chicago Illinois USA
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196
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Østergaard ME, Kumar P, Nichols J, Watt A, Sharma PK, Nielsen P, Seth PP. Allele-Selective Inhibition of Mutant Huntingtin with 2-Thio- and C5- Triazolylphenyl-Deoxythymidine-Modified Antisense Oligonucleotides. Nucleic Acid Ther 2015. [PMID: 26222265 DOI: 10.1089/nat.2015.0547] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
We report the effect of introducing a single incorporation of 2-thio-deoxythymidine (2S-dT) or C5-Triazolylphenyl-deoxythymidine (5-TrPh-dT) at four positions within the gap region of RNase H gapmer antisense oligonucleotides (ASOs) for reducing wild-type and mutant huntingtin mRNA in human patient fibroblasts. We show that these modifications can modulate processing of the ASO/RNA heteroduplexes by recombinant human RNase H1 in a position-dependent manner. We also created a structural model of the catalytic domain of human RNase H bound to ASO/RNA heteroduplexes to rationalize the activity and selectivity observations in cells and in the biochemical assays. Our results highlight the ability of chemical modifications in the gap region to produce profound changes in ASO behavior.
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Affiliation(s)
| | - Pawan Kumar
- 2 Department of Physics, Chemistry and Pharmacy, Nucleic Acid Center, University of Southern Denmark , Odense, Denmark
| | | | - Andrew Watt
- 1 Isis Pharmaceuticals , Carlsbad, California
| | - Pawan K Sharma
- 3 Department of Chemistry, Kurukshetra University , Kurukshetra, India
| | - Poul Nielsen
- 2 Department of Physics, Chemistry and Pharmacy, Nucleic Acid Center, University of Southern Denmark , Odense, Denmark
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197
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Kay C, Collins JA, Skotte NH, Southwell AL, Warby SC, Caron NS, Doty CN, Nguyen B, Griguoli A, Ross CJ, Squitieri F, Hayden MR. Huntingtin Haplotypes Provide Prioritized Target Panels for Allele-specific Silencing in Huntington Disease Patients of European Ancestry. Mol Ther 2015. [PMID: 26201449 DOI: 10.1038/mt.2015.128] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Huntington disease (HD) is a dominant neurodegenerative disorder caused by a CAG repeat expansion in the Huntingtin gene (HTT). Heterozygous polymorphisms in cis with the mutation allow for allele-specific suppression of the pathogenic HTT transcript as a therapeutic strategy. To prioritize target selection, precise heterozygosity estimates are needed across diverse HD patient populations. Here we present the first comprehensive investigation of all common target alleles across the HTT gene, using 738 reference haplotypes from the 1000 Genomes Project and 2364 haplotypes from HD patients and relatives in Canada, Sweden, France, and Italy. The most common HD haplotypes (A1, A2, and A3a) define mutually exclusive sets of polymorphisms for allele-specific therapy in the greatest number of patients. Across all four populations, a maximum of 80% are treatable using these three target haplotypes. We identify a novel deletion found exclusively on the A1 haplotype, enabling potent and selective silencing of mutant HTT in approximately 40% of the patients. Antisense oligonucleotides complementary to the deletion reduce mutant A1 HTT mRNA by 78% in patient cells while sparing wild-type HTT expression. By suppressing specific haplotypes on which expanded CAG occurs, we demonstrate a rational approach to the development of allele-specific therapy for a monogenic disorder.
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Affiliation(s)
- Chris Kay
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jennifer A Collins
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Niels H Skotte
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Amber L Southwell
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Simon C Warby
- Department of Psychiatry, Université de Montréal, Montréal, Québec, Canada
| | - Nicholas S Caron
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Crystal N Doty
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Betty Nguyen
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Annamaria Griguoli
- Neurogenetics Unit and Rare Disease Centre, IRCCS Neuromed Pozzilli (IS), Pozzilli, Italy
| | - Colin J Ross
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ferdinando Squitieri
- Neurogenetics Unit and Rare Disease Centre, IRCCS Neuromed Pozzilli (IS), Pozzilli, Italy
| | - Michael R Hayden
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada.
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198
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Huntingtin is required for ciliogenesis and neurogenesis during early Xenopus development. Dev Biol 2015; 408:305-15. [PMID: 26192473 DOI: 10.1016/j.ydbio.2015.07.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 05/09/2015] [Accepted: 07/13/2015] [Indexed: 11/21/2022]
Abstract
Huntington's Disease (HD) is a neurodegenerative disorder that results from the abnormal expansion of poly-glutamine (polyQ) repeats in the Huntingtin (HTT) gene. Although HTT has been linked to a variety of cellular events, it is still not clear what the physiological functions of the protein are. Because of its critical role during mouse embryonic mouse development, we investigated the functions of Htt during early Xenopus embryogenesis. We find that reduction of Htt levels affects cilia polarity and function and causes whole body paralysis. Moreover, Htt loss of function leads to abnormal development of trigeminal and motor neurons. Interestingly, these phenotypes are partially rescued by either wild-type or expanded HTT. These results show that the Htt activity is required for normal embryonic development, and highlight the usefulness of the Xenopus system for investigating proteins involved in human diseases.
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199
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Ultrasensitive measurement of huntingtin protein in cerebrospinal fluid demonstrates increase with Huntington disease stage and decrease following brain huntingtin suppression. Sci Rep 2015; 5:12166. [PMID: 26174131 PMCID: PMC4502413 DOI: 10.1038/srep12166] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 06/18/2015] [Indexed: 11/26/2022] Open
Abstract
Quantitation of huntingtin protein in the brain is needed, both as a marker of Huntington disease (HD) progression and for use in clinical gene silencing trials. Measurement of huntingtin in cerebrospinal fluid could be a biomarker of brain huntingtin, but traditional protein quantitation methods have failed to detect huntingtin in cerebrospinal fluid. Using micro-bead based immunoprecipitation and flow cytometry (IP-FCM), we have developed a highly sensitive mutant huntingtin detection assay. The sensitivity of huntingtin IP-FCM enables accurate detection of mutant huntingtin protein in the cerebrospinal fluid of HD patients and model mice, demonstrating that mutant huntingtin levels in cerebrospinal fluid reflect brain levels, increasing with disease stage and decreasing following brain huntingtin suppression. This technique has potential applications as a research tool and as a clinical biomarker.
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200
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Szlachcic WJ, Switonski PM, Krzyzosiak WJ, Figlerowicz M, Figiel M. Huntington disease iPSCs show early molecular changes in intracellular signaling, the expression of oxidative stress proteins and the p53 pathway. Dis Model Mech 2015; 8:1047-57. [PMID: 26092128 PMCID: PMC4582098 DOI: 10.1242/dmm.019406] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 06/11/2015] [Indexed: 12/27/2022] Open
Abstract
Huntington disease (HD) is a brain disorder characterized by the late onset of motor and cognitive symptoms, even though the neurons in the brain begin to suffer dysfunction and degeneration long before symptoms appear. There is currently no cure. Several molecular and developmental effects of HD have been identified using neural stem cells (NSCs) and differentiated cells, such as neurons and astrocytes. Still, little is known regarding the molecular pathogenesis of HD in pluripotent cells, such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). Therefore, we examined putative signaling pathways and processes involved in HD pathogenesis in pluripotent cells. We tested naïve mouse HD YAC128 iPSCs and two types of human HD iPSC that were generated from HD and juvenile-HD patients. Surprisingly, we found that a number of changes affecting cellular processes in HD were also present in undifferentiated pluripotent HD iPSCs, including the dysregulation of the MAPK and Wnt signaling pathways and the dysregulation of the expression of genes related to oxidative stress, such as Sod1. Interestingly, a common protein interactor of the huntingtin protein and the proteins in the above pathways is p53, and the expression of p53 was dysregulated in HD YAC128 iPSCs and human HD iPSCs. In summary, our findings demonstrate that multiple molecular pathways that are characteristically dysregulated in HD are already altered in undifferentiated pluripotent cells and that the pathogenesis of HD might begin during the early stages of life.
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Affiliation(s)
- Wojciech J Szlachcic
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznań 61-704, Poland
| | - Pawel M Switonski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznań 61-704, Poland
| | - Wlodzimierz J Krzyzosiak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznań 61-704, Poland
| | - Marek Figlerowicz
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznań 61-704, Poland
| | - Maciej Figiel
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznań 61-704, Poland
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