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Chung CG, Kwon MJ, Jeon KH, Hyeon DY, Han MH, Park JH, Cha IJ, Cho JH, Kim K, Rho S, Kim GR, Jeong H, Lee JW, Kim T, Kim K, Kim KP, Ehlers MD, Hwang D, Lee SB. Golgi Outpost Synthesis Impaired by Toxic Polyglutamine Proteins Contributes to Dendritic Pathology in Neurons. Cell Rep 2018; 20:356-369. [PMID: 28700938 DOI: 10.1016/j.celrep.2017.06.059] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 04/28/2017] [Accepted: 06/21/2017] [Indexed: 11/29/2022] Open
Abstract
Dendrite aberration is a common feature of neurodegenerative diseases caused by protein toxicity, but the underlying mechanisms remain largely elusive. Here, we show that nuclear polyglutamine (polyQ) toxicity resulted in defective terminal dendrite elongation accompanied by a loss of Golgi outposts (GOPs) and a decreased supply of plasma membrane (PM) in Drosophila class IV dendritic arborization (da) (C4 da) neurons. mRNA sequencing revealed that genes downregulated by polyQ proteins included many secretory pathway-related genes, including COPII genes regulating GOP synthesis. Transcription factor enrichment analysis identified CREB3L1/CrebA, which regulates COPII gene expression. CrebA overexpression in C4 da neurons restores the dysregulation of COPII genes, GOP synthesis, and PM supply. Chromatin immunoprecipitation (ChIP)-PCR revealed that CrebA expression is regulated by CREB-binding protein (CBP), which is sequestered by polyQ proteins. Furthermore, co-overexpression of CrebA and Rac1 synergistically restores the polyQ-induced dendrite pathology. Collectively, our results suggest that GOPs impaired by polyQ proteins contribute to dendrite pathology through the CBP-CrebA-COPII pathway.
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Affiliation(s)
- Chang Geon Chung
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea
| | - Min Jee Kwon
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea
| | - Keun Hye Jeon
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea; Department of Family Medicine, Samsung Medical Center, Seoul 06351, Republic of Korea
| | - Do Young Hyeon
- School of Interdisciplinary Bioscience and Bioengineering, POSTECH, Pohang 37673, Republic of Korea
| | - Myeong Hoon Han
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea
| | - Jeong Hyang Park
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea
| | - In Jun Cha
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea
| | - Jae Ho Cho
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea
| | - Kunhyung Kim
- Department of New Biology, DGIST, Daegu 42988, Republic of Korea
| | - Sangchul Rho
- Center for Plant Aging Research, Institute for Basic Science, DGIST, Daegu 42988, Republic of Korea
| | - Gyu Ree Kim
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea
| | - Hyobin Jeong
- Center for Plant Aging Research, Institute for Basic Science, DGIST, Daegu 42988, Republic of Korea
| | - Jae Won Lee
- Department of Applied Chemistry, Institute of Natural Science, College of Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
| | - TaeSoo Kim
- Department of Life Science and the Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Keetae Kim
- Department of New Biology, DGIST, Daegu 42988, Republic of Korea
| | - Kwang Pyo Kim
- Department of Applied Chemistry, Institute of Natural Science, College of Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
| | | | - Daehee Hwang
- School of Interdisciplinary Bioscience and Bioengineering, POSTECH, Pohang 37673, Republic of Korea; Department of New Biology, DGIST, Daegu 42988, Republic of Korea; Center for Plant Aging Research, Institute for Basic Science, DGIST, Daegu 42988, Republic of Korea.
| | - Sung Bae Lee
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Republic of Korea.
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Westerberg G, Chiesa JA, Andersen CA, Diamanti D, Magnoni L, Pollio G, Darpo B, Zhou M. Safety, pharmacokinetics, pharmacogenomics and QT concentration-effect modelling of the SirT1 inhibitor selisistat in healthy volunteers. Br J Clin Pharmacol 2015; 79:477-91. [PMID: 25223836 DOI: 10.1111/bcp.12513] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 09/06/2014] [Indexed: 01/05/2023] Open
Abstract
AIM Selisistat (SEN0014196), a first-in-class SirT1 inhibitor, is being developed as a disease-modifying therapy for Huntington's disease. This first-in-human study investigated the safety, pharmacokinetics and pharmacogenomics of single and multiple doses of selisistat in healthy male and female subjects. METHOD In this double-blind, randomized, placebo-controlled study, seven cohorts of eight subjects received a single dose of selisistat at dose levels of 5, 25, 75, 150, 300 and 600 mg and four cohorts of eight subjects were administered 100, 200 and 300 mg once daily for 7 days. Blood sampling and safety assessments were conducted throughout the study. RESULTS Selisistat was rapidly absorbed and systemic exposure increased in proportion to dose in the 5-300 mg range. Steady-state plasma concentrations were achieved within 4 days of repeated dosing. The incidence of drug related adverse events showed no correlation with dose level or number of doses received and was comparable with the placebo group. No serious adverse events were reported and no subjects were withdrawn due to adverse events. There were no trends in clinical laboratory parameters or vital signs. No trends in heart rate or ECG parameters, including the QTc interval and T-wave morphology, were observed. There were no findings in physical or neurological examinations or postural control. Transcriptional alteration was observed in peripheral blood. CONCLUSION Selisistat was safe and well tolerated by healthy male and female subjects after single doses up to 600 mg and multiple doses up to 300 mg day(-1).
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Affiliation(s)
- Goran Westerberg
- Siena Biotech SpA, 35, Strada del Petriccio e Belriguardo, 53100, Siena, Italy; La Crocina Pharmaceutical Consultants D.I., Podere La Crocina, 53020, San Giovanni d'Asso, Italy
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3
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Zhou YF, Liao SS, Luo YY, Tang JG, Wang JL, Lei LF, Chi JW, Du J, Jiang H, Xia K, Tang BS, Shen L. SUMO-1 modification on K166 of polyQ-expanded ataxin-3 strengthens its stability and increases its cytotoxicity. PLoS One 2013; 8:e54214. [PMID: 23382880 PMCID: PMC3561348 DOI: 10.1371/journal.pone.0054214] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2012] [Accepted: 12/10/2012] [Indexed: 12/18/2022] Open
Abstract
Post-translational modification by SUMO was proposed to modulate the pathogenesis of several neurodegenerative diseases. Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is an autosomal dominant neurodegenerative disease caused by polyQ-expanded ataxin-3. We have previously shown that ataxin-3 was a new target of SUMOylation in vitro and in vivo. Here we identified that the major SUMO-1 binding site was located on lysine 166. SUMOylation did not influence the subcellular localization, ubiquitination or aggregates formation of mutant-type ataxin-3, but partially increased its stability and the cell apoptosis. Our findings revealed the role of ataxin-3 SUMOylation in SCA3/MJD pathogenesis.
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Affiliation(s)
- Ya-Fang Zhou
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Shu-Sheng Liao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Ying-Ying Luo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Jian-Guang Tang
- Department of Neurology, the Second Xiangya Hospital, Central South University, Changsha, China
| | - Jun-Ling Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Li-Fang Lei
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Jing-Wei Chi
- National Laboratory of Medical Genetics of China, Central South University, Changsha, China
| | - Juan Du
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- National Laboratory of Medical Genetics of China, Central South University, Changsha, China
| | - Kun Xia
- National Laboratory of Medical Genetics of China, Central South University, Changsha, China
| | - Bei-Sha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- National Laboratory of Medical Genetics of China, Central South University, Changsha, China
- Neurodegenerative Disorders Research Center, Central South University, Changsha, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- Neurodegenerative Disorders Research Center, Central South University, Changsha, China
- * E-mail:
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4
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Epigenetic programming of neurodegenerative diseases by an adverse environment. Brain Res 2012; 1444:96-111. [PMID: 22330722 DOI: 10.1016/j.brainres.2012.01.038] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 01/13/2012] [Accepted: 01/17/2012] [Indexed: 02/02/2023]
Abstract
Experience and environment can critically influence the risk and progression of neurodegenerative disorders. Epigenetic mechanisms, such as miRNA expression, DNA methylation, and histone modifications, readily respond to experience and environmental factors. Here we propose that epigenetic regulation of gene expression and environmental modulation thereof may play a key role in the onset and course of common neurological conditions, including Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. For example, epigenetic mechanisms may mediate long-term responses to adverse experience, such as stress, to affect disease susceptibility and the course of neurodegenerative events. This review introduces the epigenetic components and their possible role in mediating neuropathological processes in response to stress. We argue that epigenetic modifications will affect neurodegenerative events through altered gene function. The study of epigenetic states in neurodegenerative diseases presents an opportunity to gain new insights into risk factors and pathogenic mechanisms. Moreover, research into epigenetic regulation of disease may revolutionize health care by opening new avenues of personalized, preventive and curative medicine.
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Usdin K. The biological effects of simple tandem repeats: lessons from the repeat expansion diseases. Genome Res 2008; 18:1011-9. [PMID: 18593815 DOI: 10.1101/gr.070409.107] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tandem repeats are common features of both prokaryote and eukaryote genomes, where they can be found not only in intergenic regions but also in both the noncoding and coding regions of a variety of different genes. The repeat expansion diseases are a group of human genetic disorders caused by long and highly polymorphic tandem repeats. These disorders provide many examples of the effects that such repeats can have on many biological processes. While repeats in the coding sequence can result in the generation of toxic or malfunctioning proteins, noncoding repeats can also have significant effects including the generation of chromosome fragility, the silencing of the genes in which they are located, the modulation of transcription and translation, and the sequestering of proteins involved in processes such as splicing and cell architecture.
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Affiliation(s)
- Karen Usdin
- Section on Gene Structure and Disease, Laboratory of Molecular and Cellular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0830, USA.
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6
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Abstract
The discovery that expansion of unstable repeats can cause a variety of neurological disorders has changed the landscape of disease-oriented research for several forms of mental retardation, Huntington disease, inherited ataxias, and muscular dystrophy. The dynamic nature of these mutations provided an explanation for the variable phenotype expressivity within a family. Beyond diagnosis and genetic counseling, the benefits from studying these disorders have been noted in both neurobiology and cell biology. Examples include insight about the role of translational control in synaptic plasticity, the role of RNA processing in the integrity of muscle and neuronal function, the importance of Fe-S-containing enzymes for cellular energy, and the dramatic effects of altering protein conformations on neuronal function and survival. It is exciting that within a span of 15 years, pathogenesis studies of this class of disorders are beginning to reveal pathways that are potential therapeutic targets.
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Affiliation(s)
- Harry T Orr
- Institute of Human Genetics, Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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7
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Oliveira JMA, Chen S, Almeida S, Riley R, Gonçalves J, Oliveira CR, Hayden MR, Nicholls DG, Ellerby LM, Rego AC. Mitochondrial-dependent Ca2+ handling in Huntington's disease striatal cells: effect of histone deacetylase inhibitors. J Neurosci 2006; 26:11174-86. [PMID: 17065457 PMCID: PMC6674668 DOI: 10.1523/jneurosci.3004-06.2006] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Evidence suggests that neuronal dysfunction in Huntington's disease (HD) striatum involves deficits in mitochondrial function and in Ca2+ handling. However, the relationship between mitochondria and Ca2+ handling has been incompletely studied in intact HD striatal cells. Treatment with histone deacetylase (HDAC) inhibitors reduces cell death in HD models, but the effects of this promising therapy on cellular function are mostly unknown. Here, we use real-time functional imaging of intracellular Ca2+ and mitochondrial membrane potential to explore the role of in situ HD mitochondria in Ca2+ handling. Immortalized striatal (STHdh) cells and striatal neurons from transgenic mice, expressing full-length mutant huntingtin (Htt), were used to model HD. We show that (1) active glycolysis in STHdh cells occludes the mitochondrial role in Ca2+ handling as well as the effects of mitochondrial inhibitors, (2) STHdh cells and striatal neurons in the absence of glycolysis are critically dependent on oxidative phosphorylation for energy-dependent Ca2+ handling, (3) expression of full-length mutant Htt is associated with deficits in mitochondrial-dependent Ca2+ handling that can be ameliorated by treatment with HDAC inhibitors (treatment with trichostatin A or sodium butyrate decreases the proportion of STHdh cells losing Ca2+ homeostasis after Ca2+-ionophore challenging, and accelerates the restoration of intracellular Ca2+ in striatal neurons challenged with NMDA), and (4) neurons with different response patterns to NMDA receptor activation exhibit different average somatic areas and are differentially affected by treatment with HDAC inhibitors, suggesting subpopulation or functional state specificity. These findings indicate that neuroprotection induced by HDAC inhibitors involves more efficient Ca2+ handling, thus improving the neuronal ability to cope with excitotoxic stimuli.
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Affiliation(s)
- Jorge M. A. Oliveira
- Serviço de Farmacologia da Faculdade de Farmácia, Centro de Estudos de Química Orgânica, Fitoquímica e Farmacologia, Universidade do Porto, 4050-047 Porto, Portugal
- Buck Institute for Age Research, Novato, California 94945
- Center for Neuroscience and Cell Biology and Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Sylvia Chen
- Buck Institute for Age Research, Novato, California 94945
| | - Sandra Almeida
- Center for Neuroscience and Cell Biology and Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Rebeccah Riley
- Buck Institute for Age Research, Novato, California 94945
| | - Jorge Gonçalves
- Serviço de Farmacologia da Faculdade de Farmácia, Centro de Estudos de Química Orgânica, Fitoquímica e Farmacologia, Universidade do Porto, 4050-047 Porto, Portugal
| | - Catarina R. Oliveira
- Center for Neuroscience and Cell Biology and Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Michael R. Hayden
- Department of Medical Genetics, Center for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4, and
| | | | | | - A. Cristina Rego
- Center for Neuroscience and Cell Biology and Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
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8
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Butler R, Bates GP. Histone deacetylase inhibitors as therapeutics for polyglutamine disorders. Nat Rev Neurosci 2006; 7:784-96. [PMID: 16988654 DOI: 10.1038/nrn1989] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
During the past 5 years, gene expression studies in cell culture, animal models and in the brains of patients have shown that the perturbation of transcription frequently results in neuronal dysfunction in polyglutamine repeat diseases such as Huntington's disease. Histone deacetylases act as repressors of transcription through interactions with co-repressor complexes, which leads to chromatin remodelling. Aberrant interactions between polyglutamine proteins and regulators of transcription could be one mechanism by which transcriptional dysregulation occurs. Here, we discuss the potential therapeutic pathways through which histone deacetylase inhibitors might act to correct the aberrant transcription observed in Huntington's disease and other polyglutamine repeat diseases.
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Affiliation(s)
- Rachel Butler
- King's College London School of Medicine, Department of Medical and Molecular Genetics, 8th Floor Guy's Tower, Guy's Hospital, London SE1 9RT, UK
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9
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Caron C, Boyault C, Khochbin S. Regulatory cross-talk between lysine acetylation and ubiquitination: role in the control of protein stability. Bioessays 2005; 27:408-15. [PMID: 15770681 DOI: 10.1002/bies.20210] [Citation(s) in RCA: 213] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
It is now becoming apparent that cross-talk between two protein lysine modifications, acetylation and ubiquitination, is a critical regulatory mechanism controlling vital cellular functions. The most apparent effect is the inhibition of proteasome-mediated protein degradation by lysine acetylation. Analysis of the underlying mechanisms, however, shows that, besides a direct competition between the two lysine modifications, more complex and indirect processes also connect these two signalling pathways. These findings point to protein lysine acetylation as a potential regulator of various cellular functions involving protein ubiquitination.
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Affiliation(s)
- Cécile Caron
- Laboratoire de Biologie Moléculaie et Cellulaire de la Différenciation- INSERM U309 Equipe Chromatine et expression des gènes, Institut Albert Bonniot, Faculté de. Médecine-Pharmacie, 38706 La Tronche, France
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10
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Hague SM, Klaffke S, Bandmann O. Neurodegenerative disorders: Parkinson's disease and Huntington's disease. J Neurol Neurosurg Psychiatry 2005; 76:1058-63. [PMID: 16024878 PMCID: PMC1739745 DOI: 10.1136/jnnp.2004.060186] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Parkinson's disease and Huntington's disease are both model diseases. Parkinson's disease is the most common of several akinetic-rigid syndromes and Huntington's disease is only one of an ever growing number of trinucleotide repeat disorders. Molecular genetic studies and subsequent molecular biological studies have provided fascinating new insights into the pathogenesis of both disorders and there is now real hope for disease modifying treatment in the not too distant future for patients with Parkinson's disease or Huntington's disease.
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Affiliation(s)
- S M Hague
- Academic Neurology Unit, Division of Genomic Medicine, University of Sheffield, UK.
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11
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Autosomal dominant cerebellar ataxia. NEURODEGENER DIS 2005. [DOI: 10.1017/cbo9780511544873.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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12
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McMahon SJ, Pray-Grant MG, Schieltz D, Yates JR, Grant PA. Polyglutamine-expanded spinocerebellar ataxia-7 protein disrupts normal SAGA and SLIK histone acetyltransferase activity. Proc Natl Acad Sci U S A 2005; 102:8478-82. [PMID: 15932941 PMCID: PMC1150861 DOI: 10.1073/pnas.0503493102] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Histone acetyltransferases have been shown to participate in many essential cellular processes, particularly those associated with activation of transcription. SAGA (Spt-Ada-Gcn5 acetyltransferase) and SLIK (SAGA-like) are two highly homologous multisubunit histone acetyltransferase complexes that were originally identified in the yeast Saccharomyces cerevisiae. Here, we identify the protein Sgf73/Sca7 as a component of SAGA and SLIK, and a homologue of the human SCA7-encoded protein ataxin-7, which, in its polyglutamine expanded pathological form, is responsible for the neurodegenerative disease spinocerebellar ataxia 7 (SCA7). Our findings indicate that yeast Sca7 is necessary for the integrity and function of both SAGA and SLIK, and that the human ataxin-7 is able to compliment the loss of Sca7 in yeast. A polyglutamine-expanded version of ataxin-7 assembles a SAGA complex that is depleted of critical proteins that regulate the ability of SAGA to acetylate nucleosomes. These observations have significant implications for the function of the human Sca7 protein in disease pathogenesis.
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Affiliation(s)
- Stacey J McMahon
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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13
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Michno K, van de Hoef D, Wu H, Boulianne GL. Demented flies? using Drosophila to model human neurodegenerative diseases. Clin Genet 2005; 67:468-75. [PMID: 15857410 DOI: 10.1111/j.1399-0004.2005.00448.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The success of biomedical research in the past few decades has led to dramatic improvements in human health and, as a result, increased life expectancy. An unexpected consequence, however, has been an increase in the number of age-related diseases and, in particular, neurodegenerative diseases. Despite their prevalence, a therapeutic void exists in part due to an incomplete understanding of the biochemical pathogenesis of these diseases. A powerful method that can be used to understand the basic mechanisms underlying neurodegenerative diseases is to generate animal models based on manipulating the expression of single genes that are disease causative. This approach has been facilitated by the fact that many neurodegenerative diseases are inherited as autosomal dominant traits such that expression of the mutant gene in a model organism might be expected to recapitulate the disease. During the past few years, the fruit fly, Drosophila melanogaster, has emerged as a powerful tool to model human neurodegenerative diseases. Here, we describe the various approaches utilized to create fly models of human neurodegenerative disease, and how they can aid in our understanding of disease pathogenesis and facilitate drug discovery and testing.
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Affiliation(s)
- K Michno
- Program in Developmental Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
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14
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Michno K, van de Hoef D, Wu H, Boulianne GL. Modeling age-related diseases in Drosophila: can this fly? Curr Top Dev Biol 2005; 71:199-223. [PMID: 16344106 DOI: 10.1016/s0070-2153(05)71006-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Human neurodegenerative diseases are characterized by progressive neuronal cell loss often resulting in memory and cognitive decline, motor dysfunction, and ultimately premature death. Despite the prevalence of these diseases, there are no effective cures. Insight into many of these syndromes has come from the identification of single gene mutations that are associated with inherited forms of the disease. This has led to the development of animal models in which the pathogenesis caused by these genes can be rigorously examined. Due to their short life span and powerful genetic potential, several attempts have been made to model neurodegenerative diseases in the fruit fly Drosophila melanogaster. This review will describe how these models were generated and how faithfully they recapitulate human disease. In addition, how fly models can be used to identify genetic modifiers of known disease genes and what these have revealed about the biochemical pathways underlying disease pathogenesis is discussed. Finally, the review will describe how fly models can be used to identify new therapeutic targets and test the effectiveness of new drugs.
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Affiliation(s)
- Kinga Michno
- Program in Developmental Biology, The Hospital for Sick Children, Toronto, Ontario Canada M5G 1X8
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15
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Rouaux C, Loeffler JP, Boutillier AL. Targeting CREB-binding protein (CBP) loss of function as a therapeutic strategy in neurological disorders. Biochem Pharmacol 2004; 68:1157-64. [PMID: 15313413 DOI: 10.1016/j.bcp.2004.05.035] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2004] [Accepted: 05/24/2004] [Indexed: 01/06/2023]
Abstract
Histone acetylation/deacetylation is a master regulation of gene expression. Among the enzymes involved in this process, the CREB-binding protein (CBP) displays important functions during central nervous system development. Increasing evidence shows that CBP function is altered during neurodegenerative processes. CBP loss of function has now been reported in several diseases characterized by neurological disorders such as the Rubinstein-Taybi syndrome or polyglutamine-related pathologies (Huntington's disease). Our recent work suggests that CBP loss of function could also be involved in Alzheimer's disease and amyotrophic lateral sclerosis. In a simplified apoptotic model of primary neurons, we described CBP as a substrate of apoptotic caspases, an alternative to its classical proteasomal degradation. In these neuronal death contexts, histone acetylation levels were decreased as well. Altogether, these data point to a central role of CBP loss of function during neurodegeneration. In order to restore proper acetylation levels, a proposed therapeutic strategy relies on HDAC inhibition. Nevertheless, this approach lacks of specificity. Therefore new drugs targeted at counteracting CBP loss of function could stand as a valid therapeutic approach in neurodegenerative disorders. The challenge will be to respect the fine-tuning between cellular HAT/HDAC activities.
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Affiliation(s)
- Caroline Rouaux
- Laboratoire de Signalisation Moléculaire et Neurodégénérescence-EA#3433 11, rue Humann, 67085 Strasbourg Cedex, France
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16
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Yang XJ. The diverse superfamily of lysine acetyltransferases and their roles in leukemia and other diseases. Nucleic Acids Res 2004; 32:959-76. [PMID: 14960713 PMCID: PMC384351 DOI: 10.1093/nar/gkh252] [Citation(s) in RCA: 379] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 12/22/2003] [Accepted: 01/06/2004] [Indexed: 11/12/2022] Open
Abstract
Acetylation of the epsilon-amino group of lysine residues, or N(epsilon)-lysine acetylation, is an important post-translational modification known to occur in histones, transcription factors and other proteins. Since 1995, dozens of proteins have been discovered to possess intrinsic lysine acetyltransferase activity. Although most of these enzymes were first identified as histone acetyltransferases and then tested for activities towards other proteins, acetyltransferases only modifying non-histone proteins have also been identified. Lysine acetyltransferases form different groups, three of which are Gcn5/PCAF, p300/CBP and MYST proteins. While members of the former two groups mainly function as transcriptional co-activators, emerging evidence suggests that MYST proteins, such as Esa1, Sas2, MOF, TIP60, MOZ and MORF, have diverse roles in various nuclear processes. Aberrant lysine acetylation has been implicated in oncogenesis. The genes for p300, CBP, MOZ and MORF are rearranged in recurrent leukemia-associated chromosomal abnormalities. Consistent with their roles in leukemogenesis, these acetyltransferases interact with Runx1 (or AML1), one of the most frequent targets of chromosomal translocations in leukemia. Therefore, the diverse superfamily of lysine acetyltransferases executes an acetylation program that is important for different cellular processes and perturbation of such a program may cause the development of cancer and other diseases.
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Affiliation(s)
- Xiang-Jiao Yang
- Molecular Oncology Group, Department of Medicine, McGill University Health Center, Montréal, Quebec H3A 1A1, Canada.
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17
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Abstract
Molecular motors are the long-haul carriers of eukaryotic cells, moving cargos bidirectionally along microtubule tracks. In the December 12th issue of Cell, report that HDAC6, a tubulin deacetylase, functions as an adaptor that links cargos of aggregated protein to the minus end-directed motor, cytoplasmic dynein.
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Affiliation(s)
- Ron R Kopito
- Department of Biological Sciences, Bio-X Program, Stanford University, Stanford, CA 94305, USA
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Abstract
Can Drosophila models be engineered that accurately reflect Huntington's disease (HD) and other neurological diseases and can they contribute to the search for treatments and cures? A number of publications seem to provide a resounding yes to that question. Here we seek to review some of the salient features of these models.
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Affiliation(s)
- J Lawrence Marsh
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697-2300, USA.
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Bates GP, Hockly E. Experimental therapeutics in Huntington's disease: are models useful for therapeutic trials? Curr Opin Neurol 2003; 16:465-70. [PMID: 12869804 DOI: 10.1097/01.wco.0000084223.82329.bb] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
PURPOSE OF REVIEW Research conducted over the past 10 years has uncovered molecular mechanisms that are likely to be important in the early stages of Huntington's disease pathogenesis. This review summarizes the resources and strategies that are in place in order to exploit these new findings and use them to develop novel Huntington's disease therapeutics. The role that disease models will play in this process is discussed. RECENT FINDINGS A wide variety of models of Huntington's disease have been developed including yeast, Caenorhabditis elegans, Drosophila melanogaster and mouse. These can be developed as screening assays for the identification of chemical compounds that show beneficial effects against a specific phenotype and for the cross validation of potential therapeutics. The first compounds arising through this drug development pipeline have been reported. Similarly, the preclinical screening of compounds in mouse models is being developed in a coordinated manner. SUMMARY Our understanding of the molecular basis of Huntington's disease is increasing at an exponential rate. Over the next few years an increasing number of potential therapeutic compounds will have been identified. It will only be possible to take a small number of these through to phase III clinical trials. The challenge will be to use the in-vivo models of Huntington's disease to best predict which of these compounds should be pursued in the clinic, to avoid depleting the patient population willing to enter into trials, and demoralizing them by conducting repeated unsuccessful trials.
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Mattson MP. Methylation and acetylation in nervous system development and neurodegenerative disorders. Ageing Res Rev 2003; 2:329-42. [PMID: 12726778 DOI: 10.1016/s1568-1637(03)00013-8] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The cytoarchitecture and cellular signaling mechanisms of the nervous system are complex, and this complexity is reflected at the molecular level with more genes being expressed in the nervous system than in any other tissue. Gene expression and protein function in neural cells can be regulated by methylation and acetylation. Studies of mice deficient in enzymes that control DNA methylation and of animals with a dietary deficiency of folate have established critical roles for methylation in development of the nervous system. Various neuronal proteins including histones and tubulin are regulated by acetylation which appears to serve important functions in the development, stability and plasticity of neuronal networks. Some inherited neurological disorders have recently been linked to mutations in genes that regulate DNA methylation, and alterations in DNA and protein methylation and/or acetylation have been documented in studies of age-related neurodegenerative disorders including Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD). Manipulations of methylation and acetylation can affect the vulnerability of neurons to degeneration and apoptosis in experimental models of neurodegenerative disorders, suggesting a contribution to altered methylation and acetylation to the disease processes. Interestingly, dietary factors that influence DNA methylation may affect the risk of neurodegenerative disorders, for example, individuals with low dietary folate intake are at increased risk of Alzheimer's and Parkinson's diseases.
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Affiliation(s)
- Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Gerontology Research Center, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA.
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Koeller KM, Haggarty SJ, Perkins BD, Leykin I, Wong JC, Kao MCJ, Schreiber SL. Chemical genetic modifier screens: small molecule trichostatin suppressors as probes of intracellular histone and tubulin acetylation. CHEMISTRY & BIOLOGY 2003; 10:397-410. [PMID: 12770822 DOI: 10.1016/s1074-5521(03)00093-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Histone deacetylase (HDAC) inhibitors are being developed as new clinical agents in cancer therapy, in part because they interrupt cell cycle progression in transformed cell lines. To examine cell cycle arrest induced by HDAC inhibitor trichostatin A (TSA), a cytoblot cell-based screen was used to identify small molecule suppressors of this process. TSA suppressors (ITSAs) counteract TSA-induced cell cycle arrest, histone acetylation, and transcriptional activation. Hydroxamic acid-based HDAC inhibitors like TSA and suberoylanilide hydroxamic acid (SAHA) promote acetylation of cytoplasmic alpha-tubulin as well as histones, a modification also suppressed by ITSAs. Although tubulin acetylation appears irrelevant to cell cycle progression and transcription, it may play a role in other cellular processes. Small molecule suppressors such as the ITSAs, available from chemical genetic suppressor screens, may prove to be valuable probes of many biological processes.
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Affiliation(s)
- Kathryn M Koeller
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
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Cunliffe VT. Memory by modification: the influence of chromatin structure on gene expression during vertebrate development. Gene 2003; 305:141-50. [PMID: 12609734 DOI: 10.1016/s0378-1119(03)00386-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Multicellular development is programmed by regulated interactions between transcription factors and target genes. Target genes function as nucleosomal arrays whose higher order structure, composition and accessibility to transcription machinery are strictly and dynamically controlled. Several classes of chromatin-associated proteins generate or remove localized, covalent chromatin modifications that signify gene expression status, whereas others modulate nucleosome organization and so regulate template availability for transcription. In vertebrates, covalent modification of the DNA template itself also has dramatic impacts on gene expression and development. Here I review recent discoveries that improve our understanding of the influence of chromatin structure on gene expression and I discuss their relevance to mechanisms of vertebrate development.
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Affiliation(s)
- Vincent T Cunliffe
- Centre for Developmental Genetics, School of Medicine and Biomedical Science, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK.
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Albrecht M, Hoffmann D, Evert BO, Schmitt I, Wüllner U, Lengauer T. Structural modeling of ataxin-3 reveals distant homology to adaptins. Proteins 2003; 50:355-70. [PMID: 12486728 DOI: 10.1002/prot.10280] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Spinocerebellar ataxia type 3 (SCA3) is a polyglutamine disorder caused by a CAG repeat expansion in the coding region of a gene encoding ataxin-3, a protein of yet unknown function. Based on a comprehensive computational analysis, we propose a structural model and structure-based functions for ataxin-3. Our predictive strategy comprises the compilation of multiple sequence and structure alignments of carefully selected proteins related to ataxin-3. These alignments are consistent with additional information on sequence motifs, secondary structure, and domain architectures. The application of complementary methods revealed the homology of ataxin-3 to ENTH and VHS domain proteins involved in membrane trafficking and regulatory adaptor functions. We modeled the structure of ataxin-3 using the adaptin AP180 as a template and assessed the reliability of the model by comparison with known sequence and structural features. We could further infer potential functions of ataxin-3 in agreement with known experimental data. Our database searches also identified an as yet uncharacterized family of proteins, which we named josephins because of their pronounced homology to the Josephin domain of ataxin-3.
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Affiliation(s)
- Mario Albrecht
- Fraunhofer Institute for Algorithms and Scientific Computing (SCAI), Schloss Birlinghoven, Sankt Augustin, Germany.
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