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Potapenko A, Davidson JM, Lee A, Laird AS. The deubiquitinase function of ataxin-3 and its role in the pathogenesis of Machado-Joseph disease and other diseases. Biochem J 2024; 481:461-480. [PMID: 38497605 PMCID: PMC11088879 DOI: 10.1042/bcj20240017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/04/2024] [Accepted: 03/07/2024] [Indexed: 03/19/2024]
Abstract
Machado-Joseph disease (MJD) is a devastating and incurable neurodegenerative disease characterised by progressive ataxia, difficulty speaking and swallowing. Consequently, affected individuals ultimately become wheelchair dependent, require constant care, and face a shortened life expectancy. The monogenic cause of MJD is expansion of a trinucleotide (CAG) repeat region within the ATXN3 gene, which results in polyglutamine (polyQ) expansion within the resultant ataxin-3 protein. While it is well established that the ataxin-3 protein functions as a deubiquitinating (DUB) enzyme and is therefore critically involved in proteostasis, several unanswered questions remain regarding the impact of polyQ expansion in ataxin-3 on its DUB function. Here we review the current literature surrounding ataxin-3's DUB function, its DUB targets, and what is known regarding the impact of polyQ expansion on ataxin-3's DUB function. We also consider the potential neuroprotective effects of ataxin-3's DUB function, and the intersection of ataxin-3's role as a DUB enzyme and regulator of gene transcription. Ataxin-3 is the principal pathogenic protein in MJD and also appears to be involved in cancer. As aberrant deubiquitination has been linked to both neurodegeneration and cancer, a comprehensive understanding of ataxin-3's DUB function is important for elucidating potential therapeutic targets in these complex conditions. In this review, we aim to consolidate knowledge of ataxin-3 as a DUB and unveil areas for future research to aid therapeutic targeting of ataxin-3's DUB function for the treatment of MJD and other diseases.
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Affiliation(s)
- Anastasiya Potapenko
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Jennilee M. Davidson
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Albert Lee
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Angela S. Laird
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia
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Michalak M. Calreticulin: Endoplasmic reticulum Ca 2+ gatekeeper. J Cell Mol Med 2023; 28:e17839. [PMID: 37424156 PMCID: PMC10902585 DOI: 10.1111/jcmm.17839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 07/11/2023] Open
Abstract
Endoplasmic reticulum (ER) luminal Ca2+ is vital for the function of the ER and regulates many cellular processes. Calreticulin is a highly conserved, ER-resident Ca2+ binding protein and lectin-like chaperone. Over four decades of studying calreticulin demonstrate that this protein plays a crucial role in maintaining Ca2+ supply under different physiological conditions, in managing access to Ca2+ and how Ca2+ is used depending on the environmental events and in making sure that Ca2+ is not misused. Calreticulin plays a role of ER luminal Ca2+ sensor to manage Ca2+ -dependent ER luminal events including maintaining interaction with its partners, Ca2+ handling molecules, substrates and stress sensors. The protein is strategically positioned in the lumen of the ER from where the protein manages access to and distribution of Ca2+ for many cellular Ca2+ -signalling events. The importance of calreticulin Ca2+ pool extends beyond the ER and includes influence of cellular processes involved in many aspects of cellular pathophysiology. Abnormal handling of the ER Ca2+ contributes to many pathologies from heart failure to neurodegeneration and metabolic diseases.
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Affiliation(s)
- Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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Abstract
Neurodegenerative diseases are, at present, major socio-economic burdens without effective treatments and their increasing prevalence means that these diseases will be a challenge for future generations. Neurodegenerative diseases may differ in etiology and pathology but are often caused by the accumulation of dysfunctional and aggregation-prone proteins. Autophagy, a conserved cellular mechanism, deals with cellular stress and waste product build-up and has been shown to reduce the accumulation of dysfunctional proteins in animal models of neurodegenerative diseases. Historically, progress in understanding the precise function of lipids has traditionally been far behind other biological molecules (like proteins) but emerging works demonstrate the importance of lipids in the autophagy pathway and how the disturbance of lipid metabolism is connected to neurodegeneration. Here we review how altered autophagy and the disturbance of lipid metabolism, particularly of phosphoinositols and sphingolipids, feature in neurodegenerative diseases and address work from the field that suggests that these potentially offer an opportunity of therapeutic intervention.
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Affiliation(s)
- Sergio Hernandez-Diaz
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, 33000, Bordeaux, France.,CNRS, Institut des Maladies Neurodégénératives, UMR 5293, 33000, Bordeaux, France
| | - Sandra-Fausia Soukup
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, 33000, Bordeaux, France.,CNRS, Institut des Maladies Neurodégénératives, UMR 5293, 33000, Bordeaux, France
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4
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Kristensen LV, Oppermann FS, Rauen MJ, Hartmann-Petersen R, Thirstrup K. Polyglutamine expansion of ataxin-3 alters its degree of ubiquitination and phosphorylation at specific sites. Neurochem Int 2017; 105:42-50. [PMID: 28065793 DOI: 10.1016/j.neuint.2016.12.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 11/18/2016] [Accepted: 12/20/2016] [Indexed: 02/02/2023]
Abstract
Ubiquitination and phosphorylation of proteins represent post translational modifications (PTMs) capable of regulating a variety of cellular processes. In the neurodegenerative disorder spinocerebellar ataxia type 3 (SCA3), the disease causing protein ataxin-3 carries an expanded polyglutamine (polyQ) stretch causing it to aggregate in nuclear inclusions. These inclusions are decorated with ubiquitin suggestive of a malfunction in the clearance of the mutant protein. Differences in ubiquitin chain topology between normal and polyQ expanded ataxin-3 could be involved in the differential clearance of the two proteins and play a role in SCA3 pathogenesis. Likewise, changes in phosphorylation patterns between the two variants could contribute to pathogenic processes involved in SCA3. We therefore determined the ubiquitination and phosphorylation patterns, together with the ubiquitin-linkage types associated with normal and polyQ expanded ataxin-3 by mass spectrometry (MS). This analysis revealed a similar ubiquitin linkage pattern on normal and expanded ataxin-3. However, the distribution of ubiquitinated lysine residues was altered in polyQ expanded ataxin-3, with increased ubiquitination at the new identified ubiquitination site lysine-8. MS analysis of phosphorylation also revealed novel phosphorylation sites in ataxin-3, and an increase in phosphorylation of expanded ataxin-3 at several positions. The study suggests that differences in clearance of normal and expanded ataxin-3 are not attributed to differences in ubiquitin-linkage pattern. However, the observed differences between the normal and polyQ expanded ataxin-3 with respect to the degree of ubiquitination and phosphorylation on specific sites may have an impact on ataxin-3 function and SCA3 pathogenesis.
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Affiliation(s)
- Line V Kristensen
- Department of Neurodegeneration, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark; Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark.
| | - Felix S Oppermann
- Evotec München GmbH, Am Klopferspitz 19a, 82152 Martinsried, Germany
| | - Matthias J Rauen
- Department of Neurodegeneration, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark; Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | | | - Kenneth Thirstrup
- Department of Neurodegeneration, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
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5
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Maurer MJ, Spear ED, Yu AT, Lee EJ, Shahzad S, Michaelis S. Degradation Signals for Ubiquitin-Proteasome Dependent Cytosolic Protein Quality Control (CytoQC) in Yeast. G3 (BETHESDA, MD.) 2016; 6:1853-66. [PMID: 27172186 PMCID: PMC4938640 DOI: 10.1534/g3.116.027953] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/21/2016] [Indexed: 11/18/2022]
Abstract
Cellular protein quality control (PQC) systems selectively target misfolded or otherwise aberrant proteins for degradation by the ubiquitin-proteasome system (UPS). How cells discern abnormal from normal proteins remains incompletely understood, but involves in part the recognition between ubiquitin E3 ligases and degradation signals (degrons) that are exposed in misfolded proteins. PQC is compartmentalized in the cell, and a great deal has been learned in recent years about ER-associated degradation (ERAD) and nuclear quality control. In contrast, a comprehensive view of cytosolic quality control (CytoQC) has yet to emerge, and will benefit from the development of a well-defined set of model substrates. In this study, we generated an isogenic "degron library" in Saccharomyces cerevisiae consisting of short sequences appended to the C-terminus of a reporter protein, Ura3 About half of these degron-containing proteins are substrates of the integral membrane E3 ligase Doa10, which also plays a pivotal role in ERAD and some nuclear protein degradation. Notably, some of our degron fusion proteins exhibit dependence on the E3 ligase Ltn1/Rkr1 for degradation, apparently by a mechanism distinct from its known role in ribosomal quality control of translationally paused proteins. Ubr1 and San1, E3 ligases involved in the recognition of some misfolded CytoQC substrates, are largely dispensable for the degradation of our degron-containing proteins. Interestingly, the Hsp70/Hsp40 chaperone/cochaperones Ssa1,2 and Ydj1, are required for the degradation of all constructs tested. Taken together, the comprehensive degron library presented here provides an important resource of isogenic substrates for testing candidate PQC components and identifying new ones.
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Affiliation(s)
- Matthew J Maurer
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Eric D Spear
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Allen T Yu
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Evan J Lee
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Saba Shahzad
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Susan Michaelis
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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Vavilis T, Delivanoglou N, Aggelidou E, Stamoula E, Mellidis K, Kaidoglou A, Cheva A, Pourzitaki C, Chatzimeletiou K, Lazou A, Albani M, Kritis A. Oxygen-Glucose Deprivation (OGD) Modulates the Unfolded Protein Response (UPR) and Inflicts Autophagy in a PC12 Hypoxia Cell Line Model. Cell Mol Neurobiol 2015; 36:701-12. [PMID: 26239244 DOI: 10.1007/s10571-015-0250-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 07/29/2015] [Indexed: 11/29/2022]
Abstract
Hypoxia is the lack of sufficient oxygenation of tissue, imposing severe stress upon cells. It is a major feature of many pathological conditions such as stroke, traumatic brain injury, cerebral hemorrhage, perinatal asphyxia and can lead to cell death due to energy depletion and increased free radical generation. The present study investigates the effect of hypoxia on the unfolded protein response of the cell (UPR), utilizing a 16-h oxygen-glucose deprivation protocol (OGD) in a PC12 cell line model. Expression of glucose-regulated protein 78 (GRP78) and glucose-regulated protein 94 (GRP94), key players of the UPR, was studied along with the expression of glucose-regulated protein 75 (GRP75), heat shock cognate 70 (HSC70), and glyceraldehyde 3-phosphate dehydrogenase, all with respect to the cell death mechanism(s). Cells subjected to OGD displayed upregulation of GRP78 and GRP94 and concurrent downregulation of GRP75. These findings were accompanied with minimal apoptotic cell death and induction of autophagy. The above observation warrants further investigation to elucidate whether autophagy acts as a pro-survival mechanism that upon severe and prolonged hypoxia acts as a concerted cell response leading to cell death. In our OGD model, hypoxia modulates UPR and induces autophagy.
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Affiliation(s)
- Theofanis Vavilis
- Laboratory of Physiology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Nikoleta Delivanoglou
- Laboratory of Physiology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Eleni Aggelidou
- Laboratory of Physiology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Eleni Stamoula
- Laboratory of Physiology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Kyriakos Mellidis
- Laboratory of Physiology, School of Biology, Faculty of Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Aikaterini Kaidoglou
- Laboratory of Histology, Embryology and Anthropology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Angeliki Cheva
- Department of Pathology, General Hospital of Thessaloniki "G. Papanikolaou", Thessaloniki, Greece
| | - Chryssa Pourzitaki
- Laboratory of Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Katerina Chatzimeletiou
- Unit of Human Reproduction, 1st Department of Obstetrics and Gynaecology, Aristotle University Medical School, Papageorgiou General Hospital, Thessaloniki, Greece
| | - Antigone Lazou
- Laboratory of Physiology, School of Biology, Faculty of Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Maria Albani
- Laboratory of Physiology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Aristeidis Kritis
- Laboratory of Physiology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece.
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Haberman RP, Quigley CK, Gallagher M. Characterization of CpG island DNA methylation of impairment-related genes in a rat model of cognitive aging. Epigenetics 2012; 7:1008-19. [PMID: 22869088 PMCID: PMC3515010 DOI: 10.4161/epi.21291] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Cognitive abilities, particularly memory formation, vary substantially in the elderly, with some individuals exhibiting dramatic decline with age while others maintain function well into late life. Epigenetic modifications suggest an intriguing mechanism to account for the range of cognitive outcomes in aging as they are responsive to environmental influences and affect gene transcription in cognitively relevant brain regions. Leveraging a well-characterized rat model of neurocognitive aging that recapitulates the range of outcomes seen in humans, we previously identified gene expression profiles in the CA3 subregion of the hippocampus that distinguish between young and aged subjects as well as between impaired and preserved spatial memory function. To investigate the influence of epigenetics on these profiles, we examined genomic CpG DNA methylation in the promoter regions of three neurophysiologically relevant genes (Gabra5, Hspa5 and Syn1) whose expression levels decrease with age and correlate with spatial memory performance. Consistent with mRNA decreases, DNA methylation increased in aged rats relative to young in CpG dense regions of all target promoters examined. However, no correlation with cognition was found. Focused analysis of the Gabra5 gene found that methylation changes were limited to the CpG island and varied substantially across individual CpGs. Methylation at one CpG correlated with learning and demonstrated a significant difference between memory impaired aged rats and those with intact learning. These data provide evidence that broad age-dependent DNA methylation changes occur in CpG dense promoter regions of cognitively relevant genes but suggest that methylation at single CpGs may be more pertinent to individual cognitive differences.
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Affiliation(s)
- Rebecca P Haberman
- Department of Psychological and Brain Sciences, The Johns Hopkins University, Baltimore, MD, USA.
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The yeast ubr1 ubiquitin ligase participates in a prominent pathway that targets cytosolic thermosensitive mutants for degradation. G3-GENES GENOMES GENETICS 2012; 2:619-28. [PMID: 22670231 PMCID: PMC3362944 DOI: 10.1534/g3.111.001933] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2011] [Accepted: 03/16/2012] [Indexed: 12/17/2022]
Abstract
Mutations causing protein misfolding and proteolysis are associated with many genetic diseases. The degradation of these aberrant proteins typically is mediated by protein-quality control pathways that recognize misfolded domains. Several E3 ubiquitin ligases have been shown to target cytosolic misfolded proteins to the proteasome. In this study, we characterized a panel of more than 20 cytosolic thermosensitive mutants from six essential genes in Saccharomyces cerevisiae. These wild-type proteins are stable at restrictive temperature. In contrast, we found that a large portion of the mutants is degraded at nonpermissive temperature in a proteasome-dependent manner. Approximately one-third of the assessed unstable mutants are targeted by the Ubr1 ubiquitin ligase. In two cases, efficient degradation of the thermosensitive mutants is abrogated in the absence of Ubr1 alone, whereas in a third case it is reliant on the dual deletion of Ubr1 and the nuclear E3 ligase San1. We found that the impairment of the degradation of these quality control substrates at the restrictive temperature is associated with the suppression of thermosensitive phenotype. This study confirms that Ubr1 plays an important role in the degradation of cytosolic misfolded proteins and indicates that degradation mediated by protein quality control is a major cause for the conditional lethality of mutated essential genes.
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Kritis A, Pourzitaki C, Klagas I, Chourdakis M, Albani M. Proteases inhibition assessment on PC12 and NGF treated cells after oxygen and glucose deprivation reveals a distinct role for aspartyl proteases. PLoS One 2011; 6:e25950. [PMID: 22028798 PMCID: PMC3196512 DOI: 10.1371/journal.pone.0025950] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 09/14/2011] [Indexed: 11/24/2022] Open
Abstract
Hypoxia is a severe stressful condition and induces cell death leading to neuronal loss both to the developing and adult nervous system. Central theme to cellular death is the activation of different classes of proteases such as caspases calpains and cathepsins. In the present study we investigated the involvement of these proteases, in the hypoxia-induced PC12 cell death. Rat PC12 is a model cell line for experimentation relevant to the nervous system and several protocols have been developed for either lethal hypoxia (oxygen and glucose deprivation OGD) or ischemic preconditioning (IPS). Nerve Growth Factor (NGF) treated PC12 differentiate to a sympathetic phenotype, expressing neurites and excitability. Lethal hypoxia was established by exposing undifferentiated and NGF-treated PC12 cells to a mixture of N2/CO2 (93:5%) in DMEM depleted of glucose and sodium pyruvate for 16 h. The involvement of caspases, calpains and lysosomal cathepsins D and E to the cell death induced by lethal OGD was investigated employing protease specific inhibitors such as z-VAD-fmk for the caspases, MDL28170 for the calpains and pepstatin A for the cathepsins D and E. Our findings show that pepstatin A provides statistically significant protection from cell death of both naive and NGF treated PC12 cells exposed to lethal OGD. We propose that apart from the established processes of apoptosis and necrosis that are integral components of lethal OGD, the activation of cathepsins D and E launches additional cell death pathways in which these proteases are key partners.
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Affiliation(s)
- Aristidis Kritis
- Laboratory of Physiology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece.
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10
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Protein quality control mechanisms and neurodegenerative disorders: Checks, balances and deadlocks. Neurosci Res 2010; 68:159-66. [DOI: 10.1016/j.neures.2010.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Revised: 07/24/2010] [Accepted: 08/01/2010] [Indexed: 11/19/2022]
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Franssens V, Boelen E, Anandhakumar J, Vanhelmont T, Büttner S, Winderickx J. Yeast unfolds the road map toward α-synuclein-induced cell death. Cell Death Differ 2009; 17:746-53. [DOI: 10.1038/cdd.2009.203] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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Zhong N, Ramaswamy G, Weisgraber KH. Apolipoprotein E4 domain interaction induces endoplasmic reticulum stress and impairs astrocyte function. J Biol Chem 2009; 284:27273-80. [PMID: 19666463 PMCID: PMC2785655 DOI: 10.1074/jbc.m109.014464] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Domain interaction, a structural property of apolipoprotein E4 (apoE4), is predicted to contribute to the association of apoE4 with Alzheimer disease. Arg-61 apoE mice, a gene-targeted mouse model specific for domain interaction, have lower brain apoE levels and synaptic, functional, and cognitive deficits. We hypothesized that domain interaction elicits an endoplasmic reticulum (ER) stress in astrocytes and an unfolded protein response that targets Arg-61 apoE for degradation. Primary Arg-61 apoE astrocytes had less intracellular apoE than wild-type astrocytes, and unfolded protein response markers OASIS (old astrocyte specifically induced substance), ATF4, and XBP-1 and downstream effectors were up-regulated. ER stress appears to cause global astrocyte dysfunction as glucose uptake was decreased in Arg-61 apoE astrocytes, and astrocyte-conditioned medium promoted neurite outgrowth less efficiently than wild-type medium in Neuro-2a cell cultures. We showed age-dependent up-regulation of brain OASIS levels and processing in Arg-61 apoE mice. ER stress and astrocyte dysfunction represent a new paradigm underlying the association of apoE4 with neurodegeneration.
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Affiliation(s)
- Ning Zhong
- Gladstone Institute of Neurological Disease, San Francisco, California 94158, USA
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Orosz F, Lehotzky A, Oláh J, Ovádi J. TPPP/p25: A New Unstructured Protein Hallmarking Synucleinopathies. PROTEIN FOLDING AND MISFOLDING: NEURODEGENERATIVE DISEASES 2008. [DOI: 10.1007/978-1-4020-9434-7_10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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