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Serrano J, Martine L, Grosjean Y, Acar N, Alves G, Masson EAY. The importance of choosing the appropriate cholesterol quantification method: enzymatic assay versus gas chromatography. J Lipid Res 2024; 65:100561. [PMID: 38762123 PMCID: PMC11237936 DOI: 10.1016/j.jlr.2024.100561] [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: 02/06/2024] [Revised: 04/11/2024] [Accepted: 05/14/2024] [Indexed: 05/20/2024] Open
Abstract
Cholesterol is a major lipid of the animal realm with many biological roles. It is an important component of cellular membranes and a precursor of steroid hormones and bile acids. It is particularly abundant in nervous tissues, and dysregulation of cholesterol metabolism has been associated with neurodegenerative diseases such as Alzheimer's and Huntington's diseases. Deciphering the pathophysiological mechanisms of these disorders often involves animal models such as mice and Drosophila. Accurate quantification of cholesterol levels in the chosen models is a critical point of these studies. In the present work, we compare two common methods, gas chromatography coupled to flame-ionization detection (GC/FID) and a cholesterol oxidase-based fluorometric assay to measure cholesterol in mouse brains and Drosophila heads. Cholesterol levels measured by the two methods were similar for the mouse brain, which presents a huge majority of cholesterol in its sterol profile. On the contrary, depending on the method, measured cholesterol levels were very different for Drosophila heads, which present a complex sterol profile with a minority of cholesterol. We showed that the enzyme-based assay is not specific for cholesterol and detects other sterols as well. This method is therefore not suited for cholesterol measurement in models such as Drosophila. Alternatively, chromatographic methods, such as GC/FID, offer the required specificity for cholesterol quantification. Understanding the limitations of the quantification techniques is essential for reliable interpretation of the results in cholesterol-related research.
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Affiliation(s)
- Jeanne Serrano
- Eye & Nutrition Research Group, Centre des Sciences du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, Dijon, France; Sensory Perception & Glia-Neuron Interaction Research Group, Centre des Sciences du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, Dijon, France
| | - Lucy Martine
- Eye & Nutrition Research Group, Centre des Sciences du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, Dijon, France
| | - Yaël Grosjean
- Sensory Perception & Glia-Neuron Interaction Research Group, Centre des Sciences du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, Dijon, France
| | - Niyazi Acar
- Eye & Nutrition Research Group, Centre des Sciences du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, Dijon, France
| | - Georges Alves
- Sensory Perception & Glia-Neuron Interaction Research Group, Centre des Sciences du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, Dijon, France.
| | - Elodie A Y Masson
- Eye & Nutrition Research Group, Centre des Sciences du Goût et de l'Alimentation, CNRS, INRAE, Institut Agro, Université de Bourgogne, Dijon, France.
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2
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Shaheen A, Richter Gorey CL, Sghaier A, Dason JS. Cholesterol is required for activity-dependent synaptic growth. J Cell Sci 2023; 136:jcs261563. [PMID: 37902091 DOI: 10.1242/jcs.261563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/24/2023] [Indexed: 10/31/2023] Open
Abstract
Changes in cholesterol content of neuronal membranes occur during development and brain aging. Little is known about whether synaptic activity regulates cholesterol levels in neuronal membranes and whether these changes affect neuronal development and function. We generated transgenic flies that express the cholesterol-binding D4H domain of perfringolysin O toxin and found increased levels of cholesterol in presynaptic terminals of Drosophila larval neuromuscular junctions following increased synaptic activity. Reduced cholesterol impaired synaptic growth and largely prevented activity-dependent synaptic growth. Presynaptic knockdown of adenylyl cyclase phenocopied the impaired synaptic growth caused by reducing cholesterol. Furthermore, the effects of knocking down adenylyl cyclase and reducing cholesterol were not additive, suggesting that they function in the same pathway. Increasing cAMP levels using a dunce mutant with reduced phosphodiesterase activity failed to rescue this impaired synaptic growth, suggesting that cholesterol functions downstream of cAMP. We used a protein kinase A (PKA) sensor to show that reducing cholesterol levels reduced presynaptic PKA activity. Collectively, our results demonstrate that enhanced synaptic activity increased cholesterol levels in presynaptic terminals and that these changes likely activate the cAMP-PKA pathway during activity-dependent growth.
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Affiliation(s)
- Amber Shaheen
- Department of Biomedical Sciences, University of Windsor, Windsor, Ontario, N9B 3P4, Canada
| | - Claire L Richter Gorey
- Department of Biomedical Sciences, University of Windsor, Windsor, Ontario, N9B 3P4, Canada
| | - Adam Sghaier
- Department of Biomedical Sciences, University of Windsor, Windsor, Ontario, N9B 3P4, Canada
| | - Jeffrey S Dason
- Department of Biomedical Sciences, University of Windsor, Windsor, Ontario, N9B 3P4, Canada
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3
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Eberwein AE, Kulkarni SS, Rushton E, Broadie K. Glycosphingolipids are linked to elevated neurotransmission and neurodegeneration in a Drosophila model of Niemann Pick type C. Dis Model Mech 2023; 16:dmm050206. [PMID: 37815467 PMCID: PMC10581387 DOI: 10.1242/dmm.050206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 09/27/2023] [Indexed: 10/11/2023] Open
Abstract
The lipid storage disease Niemann Pick type C (NPC) causes neurodegeneration owing primarily to loss of NPC1. Here, we employed a Drosophila model to test links between glycosphingolipids, neurotransmission and neurodegeneration. We found that Npc1a nulls had elevated neurotransmission at the glutamatergic neuromuscular junction (NMJ), which was phenocopied in brainiac (brn) mutants, impairing mannosyl glucosylceramide (MacCer) glycosylation. Npc1a; brn double mutants had the same elevated synaptic transmission, suggesting that Npc1a and brn function within the same pathway. Glucosylceramide (GlcCer) synthase inhibition with miglustat prevented elevated neurotransmission in Npc1a and brn mutants, further suggesting epistasis. Synaptic MacCer did not accumulate in the NPC model, but GlcCer levels were increased, suggesting that GlcCer is responsible for the elevated synaptic transmission. Null Npc1a mutants had heightened neurodegeneration, but no significant motor neuron or glial cell death, indicating that dying cells are interneurons and that elevated neurotransmission precedes neurodegeneration. Glycosphingolipid synthesis mutants also had greatly heightened neurodegeneration, with similar neurodegeneration in Npc1a; brn double mutants, again suggesting that Npc1a and brn function in the same pathway. These findings indicate causal links between glycosphingolipid-dependent neurotransmission and neurodegeneration in this NPC disease model.
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Affiliation(s)
- Anna E. Eberwein
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
| | - Swarat S. Kulkarni
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
| | - Emma Rushton
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
| | - Kendal Broadie
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
- Department of Cell and Developmental Biology, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
- Vanderbilt Brain Institute, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
- Kennedy Center for Research on Human Development, Vanderbilt University and Medical Center, Nashville, TN 37235, USA
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4
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Yu M, Ye H, De-Paula RB, Mangleburg CG, Wu T, Lee TV, Li Y, Duong D, Phillips B, Cruchaga C, Allen GI, Seyfried NT, Al-Ramahi I, Botas J, Shulman JM. Functional screening of lysosomal storage disorder genes identifies modifiers of alpha-synuclein neurotoxicity. PLoS Genet 2023; 19:e1010760. [PMID: 37200393 DOI: 10.1371/journal.pgen.1010760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 05/31/2023] [Accepted: 04/25/2023] [Indexed: 05/20/2023] Open
Abstract
Heterozygous variants in the glucocerebrosidase (GBA) gene are common and potent risk factors for Parkinson's disease (PD). GBA also causes the autosomal recessive lysosomal storage disorder (LSD), Gaucher disease, and emerging evidence from human genetics implicates many other LSD genes in PD susceptibility. We have systemically tested 86 conserved fly homologs of 37 human LSD genes for requirements in the aging adult Drosophila brain and for potential genetic interactions with neurodegeneration caused by α-synuclein (αSyn), which forms Lewy body pathology in PD. Our screen identifies 15 genetic enhancers of αSyn-induced progressive locomotor dysfunction, including knockdown of fly homologs of GBA and other LSD genes with independent support as PD susceptibility factors from human genetics (SCARB2, SMPD1, CTSD, GNPTAB, SLC17A5). For several genes, results from multiple alleles suggest dose-sensitivity and context-dependent pleiotropy in the presence or absence of αSyn. Homologs of two genes causing cholesterol storage disorders, Npc1a / NPC1 and Lip4 / LIPA, were independently confirmed as loss-of-function enhancers of αSyn-induced retinal degeneration. The enzymes encoded by several modifier genes are upregulated in αSyn transgenic flies, based on unbiased proteomics, revealing a possible, albeit ineffective, compensatory response. Overall, our results reinforce the important role of lysosomal genes in brain health and PD pathogenesis, and implicate several metabolic pathways, including cholesterol homeostasis, in αSyn-mediated neurotoxicity.
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Affiliation(s)
- Meigen Yu
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
| | - Hui Ye
- Department of Neurology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Ruth B De-Paula
- Quantitative and Computational Biology Program, Baylor College of Medicine, Houston, Texas, United States of America
| | - Carl Grant Mangleburg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas, United States of America
| | - Timothy Wu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas, United States of America
| | - Tom V Lee
- Department of Neurology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Yarong Li
- Department of Neurology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Duc Duong
- Departments of Biochemistry and Neurology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Bridget Phillips
- Department of Psychiatry, Washington University, St. Louis, Missouri, United States of America
- NeuroGenomics and Informatics, Washington University, St. Louis, Missouri, United States of America
| | - Carlos Cruchaga
- Department of Psychiatry, Washington University, St. Louis, Missouri, United States of America
- NeuroGenomics and Informatics, Washington University, St. Louis, Missouri, United States of America
| | - Genevera I Allen
- Departments of Electrical and Computer Engineering, Computer Science, and Statistics, Rice University, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, United States of America
| | - Nicholas T Seyfried
- Departments of Biochemistry and Neurology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Ismael Al-Ramahi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, United States of America
- Center for Alzheimer's and Neurodegenerative Diseases, Baylor College of Medicine, Houston, Texas, United States of America
| | - Juan Botas
- Quantitative and Computational Biology Program, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, United States of America
- Center for Alzheimer's and Neurodegenerative Diseases, Baylor College of Medicine, Houston, Texas, United States of America
| | - Joshua M Shulman
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neurology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, United States of America
- Center for Alzheimer's and Neurodegenerative Diseases, Baylor College of Medicine, Houston, Texas, United States of America
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5
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Pan X, Dutta D, Lu S, Bellen HJ. Sphingolipids in neurodegenerative diseases. Front Neurosci 2023; 17:1137893. [PMID: 36875645 PMCID: PMC9978793 DOI: 10.3389/fnins.2023.1137893] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 01/27/2023] [Indexed: 02/18/2023] Open
Abstract
Neurodegenerative Diseases (NDDs) are a group of disorders that cause progressive deficits of neuronal function. Recent evidence argues that sphingolipid metabolism is affected in a surprisingly broad set of NDDs. These include some lysosomal storage diseases (LSDs), hereditary sensory and autonomous neuropathy (HSAN), hereditary spastic paraplegia (HSP), infantile neuroaxonal dystrophy (INAD), Friedreich's ataxia (FRDA), as well as some forms of amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD). Many of these diseases have been modeled in Drosophila melanogaster and are associated with elevated levels of ceramides. Similar changes have also been reported in vertebrate cells and mouse models. Here, we summarize studies using fly models and/or patient samples which demonstrate the nature of the defects in sphingolipid metabolism, the organelles that are implicated, the cell types that are initially affected, and potential therapeutics for these diseases.
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Affiliation(s)
- Xueyang Pan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Debdeep Dutta
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
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6
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The Role of Membrane Lipids in Light-Activation of Drosophila TRP Channels. Biomolecules 2022; 12:biom12030382. [PMID: 35327573 PMCID: PMC8945425 DOI: 10.3390/biom12030382] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 12/28/2022] Open
Abstract
Transient Receptor Potential (TRP) channels constitute a large superfamily of polymodal channel proteins with diverse roles in many physiological and sensory systems that function both as ionotropic and metabotropic receptors. From the early days of TRP channel discovery, membrane lipids were suggested to play a fundamental role in channel activation and regulation. A prominent example is the Drosophila TRP and TRP-like (TRPL) channels, which are predominantly expressed in the visual system of Drosophila. Light activation of the TRP and TRPL channels, the founding members of the TRP channel superfamily, requires activation of phospholipase Cβ (PLC), which hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) into Diacylglycerol (DAG) and Inositol 1, 4,5-trisphosphate (IP3). However, the events required for channel gating downstream of PLC activation are still under debate and led to several hypotheses regarding the mechanisms by which lipids gate the channels. Despite many efforts, compelling evidence of the involvement of DAG accumulation, PIP2 depletion or IP3-mediated Ca2+ release in light activation of the TRP/TRPL channels are still lacking. Exogeneous application of poly unsaturated fatty acids (PUFAs), a product of DAG hydrolysis was demonstrated as an efficient way to activate the Drosophila TRP/TRPL channels. However, compelling evidence for the involvement of PUFAs in physiological light-activation of the TRP/TRPL channels is still lacking. Light-induced mechanical force generation was measured in photoreceptor cells prior to channel opening. This mechanical force depends on PLC activity, suggesting that the enzymatic activity of PLC converting PIP2 into DAG generates membrane tension, leading to mechanical gating of the channels. In this review, we will present the roles of membrane lipids in light activation of Drosophila TRP channels and present the many advantages of this model system in the exploration of TRP channel activation under physiological conditions.
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7
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Texada MJ, Lassen M, Pedersen LH, Koyama T, Malita A, Rewitz K. Insulin signaling couples growth and early maturation to cholesterol intake in Drosophila. Curr Biol 2022; 32:1548-1562.e6. [PMID: 35245460 DOI: 10.1016/j.cub.2022.02.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 12/10/2021] [Accepted: 02/04/2022] [Indexed: 11/28/2022]
Abstract
Nutrition is one of the most important influences on growth and the timing of maturational transitions including mammalian puberty and insect metamorphosis. Childhood obesity is associated with precocious puberty, but the assessment mechanism that links body fat to early maturation is unknown. During development, the intake of nutrients promotes signaling through insulin-like systems that govern the growth of cells and tissues and also regulates the timely production of the steroid hormones that initiate the juvenile-adult transition. We show here that the dietary lipid cholesterol, which is required as a component of cell membranes and as a substrate for steroid biosynthesis, also governs body growth and maturation in Drosophila via promoting the expression and release of insulin-like peptides. This nutritional input acts via the nutrient sensor TOR, which is regulated by the Niemann-Pick-type-C 1 (Npc1) cholesterol transporter, in the glia of the blood-brain barrier and cells of the adipose tissue to remotely drive systemic insulin signaling and body growth. Furthermore, increasing intracellular cholesterol levels in the steroid-producing prothoracic gland strongly promotes endoreduplication, leading to an accelerated attainment of a nutritional checkpoint that normally ensures that animals do not initiate maturation prematurely. These findings, therefore, show that a Npc1-TOR signaling system couples the sensing of the lipid cholesterol with cellular and systemic growth control and maturational timing, which may help explain both the link between cholesterol and cancer as well as the connection between body fat (obesity) and early puberty.
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Affiliation(s)
- Michael J Texada
- Department of Biology, Section for Cell and Neurobiology, University of Copenhagen, Universitetsparken 15, Building 3, 2100 Copenhagen, Denmark.
| | - Mette Lassen
- Department of Biology, Section for Cell and Neurobiology, University of Copenhagen, Universitetsparken 15, Building 3, 2100 Copenhagen, Denmark
| | - Lisa H Pedersen
- Department of Biology, Section for Cell and Neurobiology, University of Copenhagen, Universitetsparken 15, Building 3, 2100 Copenhagen, Denmark
| | - Takashi Koyama
- Department of Biology, Section for Cell and Neurobiology, University of Copenhagen, Universitetsparken 15, Building 3, 2100 Copenhagen, Denmark
| | - Alina Malita
- Department of Biology, Section for Cell and Neurobiology, University of Copenhagen, Universitetsparken 15, Building 3, 2100 Copenhagen, Denmark
| | - Kim Rewitz
- Department of Biology, Section for Cell and Neurobiology, University of Copenhagen, Universitetsparken 15, Building 3, 2100 Copenhagen, Denmark.
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Glial contribution to cyclodextrin-mediated reversal of cholesterol accumulation in murine NPC1-deficient neurons in vivo. Neurobiol Dis 2021; 158:105469. [PMID: 34364974 DOI: 10.1016/j.nbd.2021.105469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 07/17/2021] [Accepted: 08/02/2021] [Indexed: 12/11/2022] Open
Abstract
Niemann-Pick type C disease is a rare and fatal lysosomal storage disorder presenting severe neurovisceral symptoms. Disease-causing mutations in genes encoding either NPC1 or NPC2 protein provoke accumulation of cholesterol and other lipids in specific structures of the endosomal-lysosomal system and degeneration of specific cells, notably neurons in the central nervous system (CNS). 2-hydroxypropyl-beta-cyclodextrin (CD) emerged as potential therapeutic approach based on animal studies and clinical data, but the mechanism of action in neurons has remained unclear. To address this topic in vivo, we took advantage of the retina as highly accessible part of the CNS and intravitreal injections as mode of drug administration. Coupling CD to gold nanoparticles allowed us to trace its intracellular location. We report that CD enters the endosomal-lysosomal system of neurons in vivo and enables the release of lipid-laden lamellar inclusions, which are then removed from the extracellular space by specific types of glial cells. Our data suggest that CD induces a concerted action of neurons and glial cells to restore lipid homeostasis in the central nervous system.
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9
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Rigon L, De Filippis C, Napoli B, Tomanin R, Orso G. Exploiting the Potential of Drosophila Models in Lysosomal Storage Disorders: Pathological Mechanisms and Drug Discovery. Biomedicines 2021; 9:biomedicines9030268. [PMID: 33800050 PMCID: PMC8000850 DOI: 10.3390/biomedicines9030268] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 02/18/2021] [Accepted: 03/03/2021] [Indexed: 12/12/2022] Open
Abstract
Lysosomal storage disorders (LSDs) represent a complex and heterogeneous group of rare genetic diseases due to mutations in genes coding for lysosomal enzymes, membrane proteins or transporters. This leads to the accumulation of undegraded materials within lysosomes and a broad range of severe clinical features, often including the impairment of central nervous system (CNS). When available, enzyme replacement therapy slows the disease progression although it is not curative; also, most recombinant enzymes cannot cross the blood-brain barrier, leaving the CNS untreated. The inefficient degradative capability of the lysosomes has a negative impact on the flux through the endolysosomal and autophagic pathways; therefore, dysregulation of these pathways is increasingly emerging as a relevant disease mechanism in LSDs. In the last twenty years, different LSD Drosophila models have been generated, mainly for diseases presenting with neurological involvement. The fruit fly provides a large selection of tools to investigate lysosomes, autophagy and endocytic pathways in vivo, as well as to analyse neuronal and glial cells. The possibility to use Drosophila in drug repurposing and discovery makes it an attractive model for LSDs lacking effective therapies. Here, ee describe the major cellular pathways implicated in LSDs pathogenesis, the approaches available for their study and the Drosophila models developed for these diseases. Finally, we highlight a possible use of LSDs Drosophila models for drug screening studies.
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Affiliation(s)
- Laura Rigon
- Fondazione Istituto di Ricerca Pediatrica “Città della Speranza”, Corso Stati Uniti 4, 35127 Padova, Italy; (C.D.F.); (R.T.)
- Correspondence:
| | - Concetta De Filippis
- Fondazione Istituto di Ricerca Pediatrica “Città della Speranza”, Corso Stati Uniti 4, 35127 Padova, Italy; (C.D.F.); (R.T.)
- Laboratory of Diagnosis and Therapy of Lysosomal Disorders, Department of Women’s and Children’s Health, University of Padova, Via Giustiniani 3, 35128 Padova, Italy
| | - Barbara Napoli
- Laboratory of Molecular Biology, Scientific Institute, IRCCS Eugenio Medea, Via Don Luigi Monza 20, Bosisio Parini, 23842 Lecco, Italy;
| | - Rosella Tomanin
- Fondazione Istituto di Ricerca Pediatrica “Città della Speranza”, Corso Stati Uniti 4, 35127 Padova, Italy; (C.D.F.); (R.T.)
- Laboratory of Diagnosis and Therapy of Lysosomal Disorders, Department of Women’s and Children’s Health, University of Padova, Via Giustiniani 3, 35128 Padova, Italy
| | - Genny Orso
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy;
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10
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Loss of NPC1 enhances phagocytic uptake and impairs lipid trafficking in microglia. Nat Commun 2021; 12:1158. [PMID: 33627648 PMCID: PMC7904859 DOI: 10.1038/s41467-021-21428-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 01/27/2021] [Indexed: 02/08/2023] Open
Abstract
Niemann-Pick type C disease is a rare neurodegenerative disorder mainly caused by mutations in NPC1, resulting in abnormal late endosomal/lysosomal lipid storage. Although microgliosis is a prominent pathological feature, direct consequences of NPC1 loss on microglial function remain not fully characterized. We discovered pathological proteomic signatures and phenotypes in NPC1-deficient murine models and demonstrate a cell autonomous function of NPC1 in microglia. Loss of NPC1 triggers enhanced phagocytic uptake and impaired myelin turnover in microglia that precede neuronal death. Npc1−/− microglia feature a striking accumulation of multivesicular bodies and impaired trafficking of lipids to lysosomes while lysosomal degradation function remains preserved. Molecular and functional defects were also detected in blood-derived macrophages of NPC patients that provide a potential tool for monitoring disease. Our study underscores an essential cell autonomous role for NPC1 in immune cells and implies microglial therapeutic potential. Niemann-Pick type C disease is a rare childhood neurodegenerative disorder predominantly caused by mutations in NPC1, resulting in abnormal late endosomal and lysosomal defects. Here the authors show that NPC1 disruption largely impairs microglial function.
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11
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Understanding and Treating Niemann-Pick Type C Disease: Models Matter. Int J Mol Sci 2020; 21:ijms21238979. [PMID: 33256121 PMCID: PMC7730076 DOI: 10.3390/ijms21238979] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 02/06/2023] Open
Abstract
Biomedical research aims to understand the molecular mechanisms causing human diseases and to develop curative therapies. So far, these goals have been achieved for a small fraction of diseases, limiting factors being the availability, validity, and use of experimental models. Niemann–Pick type C (NPC) is a prime example for a disease that lacks a curative therapy despite substantial breakthroughs. This rare, fatal, and autosomal-recessive disorder is caused by defects in NPC1 or NPC2. These ubiquitously expressed proteins help cholesterol exit from the endosomal–lysosomal system. The dysfunction of either causes an aberrant accumulation of lipids with patients presenting a large range of disease onset, neurovisceral symptoms, and life span. Here, we note general aspects of experimental models, we describe the line-up used for NPC-related research and therapy development, and we provide an outlook on future topics.
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12
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Chung HL, Wangler MF, Marcogliese PC, Jo J, Ravenscroft TA, Zuo Z, Duraine L, Sadeghzadeh S, Li-Kroeger D, Schmidt RE, Pestronk A, Rosenfeld JA, Burrage L, Herndon MJ, Chen S, Shillington A, Vawter-Lee M, Hopkin R, Rodriguez-Smith J, Henrickson M, Lee B, Moser AB, Jones RO, Watkins P, Yoo T, Mar S, Choi M, Bucelli RC, Yamamoto S, Lee HK, Prada CE, Chae JH, Vogel TP, Bellen HJ. Loss- or Gain-of-Function Mutations in ACOX1 Cause Axonal Loss via Different Mechanisms. Neuron 2020; 106:589-606.e6. [PMID: 32169171 PMCID: PMC7289150 DOI: 10.1016/j.neuron.2020.02.021] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 01/03/2020] [Accepted: 02/13/2020] [Indexed: 12/01/2022]
Abstract
ACOX1 (acyl-CoA oxidase 1) encodes the first and rate-limiting enzyme of the very-long-chain fatty acid (VLCFA) β-oxidation pathway in peroxisomes and leads to H2O2 production. Unexpectedly, Drosophila (d) ACOX1 is mostly expressed and required in glia, and loss of ACOX1 leads to developmental delay, pupal death, reduced lifespan, impaired synaptic transmission, and glial and axonal loss. Patients who carry a previously unidentified, de novo, dominant variant in ACOX1 (p.N237S) also exhibit glial loss. However, this mutation causes increased levels of ACOX1 protein and function resulting in elevated levels of reactive oxygen species in glia in flies and murine Schwann cells. ACOX1 (p.N237S) patients exhibit a severe loss of Schwann cells and neurons. However, treatment of flies and primary Schwann cells with an antioxidant suppressed the p.N237S-induced neurodegeneration. In summary, both loss and gain of ACOX1 lead to glial and neuronal loss, but different mechanisms are at play and require different treatments.
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Affiliation(s)
- Hyung-Lok Chung
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Michael F Wangler
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Paul C Marcogliese
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Juyeon Jo
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Department of Pediatrics, Section of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Thomas A Ravenscroft
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Zhongyuan Zuo
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Lita Duraine
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sina Sadeghzadeh
- Department of Psychology, Harvard University, Cambridge, MA 02138, USA
| | - David Li-Kroeger
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Robert E Schmidt
- Department of Pathology and Immunology, Division of Neuropathology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Alan Pestronk
- Department of Pathology and Immunology, Division of Neuropathology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lindsay Burrage
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mitchell J Herndon
- Department of Pathology and Immunology, Division of Neuropathology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Shan Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Amelle Shillington
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Marissa Vawter-Lee
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA; Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Robert Hopkin
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Jackeline Rodriguez-Smith
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA; Division of Rheumatology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Michael Henrickson
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA; Division of Rheumatology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Brendan Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ann B Moser
- Division of Neurogenetics, Kennedy Krieger Institute, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Richard O Jones
- Division of Neurogenetics, Kennedy Krieger Institute, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Paul Watkins
- Division of Neurogenetics, Kennedy Krieger Institute, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Taekyeong Yoo
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Soe Mar
- Department of Neurology, St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Murim Choi
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Robert C Bucelli
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hyun Kyoung Lee
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Pediatrics, Section of Neurology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Carlos E Prada
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Jong-Hee Chae
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Tiphanie P Vogel
- Department of Pediatrics, Section of Rheumatology, Baylor College of Medicine, Center for Human Immunobiology, Texas Children's Hospital, Houston, TX 77030, USA
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.
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13
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Lakkaraju A, Umapathy A, Tan LX, Daniele L, Philp NJ, Boesze-Battaglia K, Williams DS. The cell biology of the retinal pigment epithelium. Prog Retin Eye Res 2020; 78:100846. [PMID: 32105772 PMCID: PMC8941496 DOI: 10.1016/j.preteyeres.2020.100846] [Citation(s) in RCA: 185] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/19/2020] [Accepted: 02/23/2020] [Indexed: 02/07/2023]
Abstract
The retinal pigment epithelium (RPE), a monolayer of post-mitotic polarized epithelial cells, strategically situated between the photoreceptors and the choroid, is the primary caretaker of photoreceptor health and function. Dysfunction of the RPE underlies many inherited and acquired diseases that cause permanent blindness. Decades of research have yielded valuable insight into the cell biology of the RPE. In recent years, new technologies such as live-cell imaging have resulted in major advancement in our understanding of areas such as the daily phagocytosis and clearance of photoreceptor outer segment tips, autophagy, endolysosome function, and the metabolic interplay between the RPE and photoreceptors. In this review, we aim to integrate these studies with an emphasis on appropriate models and techniques to investigate RPE cell biology and metabolism, and discuss how RPE cell biology informs our understanding of retinal disease.
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Affiliation(s)
- Aparna Lakkaraju
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
| | - Ankita Umapathy
- Department of Ophthalmology and Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Li Xuan Tan
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
| | - Lauren Daniele
- Department of Biochemistry, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nancy J Philp
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Kathleen Boesze-Battaglia
- Department of Biochemistry, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David S Williams
- Department of Ophthalmology and Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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14
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Parker H, Ellison SM, Holley RJ, O'Leary C, Liao A, Asadi J, Glover E, Ghosh A, Jones S, Wilkinson FL, Brough D, Pinteaux E, Boutin H, Bigger BW. Haematopoietic stem cell gene therapy with IL-1Ra rescues cognitive loss in mucopolysaccharidosis IIIA. EMBO Mol Med 2020; 12:e11185. [PMID: 32057196 PMCID: PMC7059006 DOI: 10.15252/emmm.201911185] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 01/15/2020] [Accepted: 01/17/2020] [Indexed: 01/12/2023] Open
Abstract
Mucopolysaccharidosis IIIA is a neuronopathic lysosomal storage disease, characterised by heparan sulphate and other substrates accumulating in the brain. Patients develop behavioural disturbances and cognitive decline, a possible consequence of neuroinflammation and abnormal substrate accumulation. Interleukin (IL)‐1β and interleukin‐1 receptor antagonist (IL‐1Ra) expression were significantly increased in both murine models and human MPSIII patients. We identified pathogenic mechanisms of inflammasome activation, including that disease‐specific 2‐O‐sulphated heparan sulphate was essential for priming an IL‐1β response via the Toll‐like receptor 4 complex. However, mucopolysaccharidosis IIIA primary and secondary storage substrates, such as amyloid beta, were both required to activate the NLRP3 inflammasome and initiate IL‐1β secretion. IL‐1 blockade in mucopolysaccharidosis IIIA mice using IL‐1 receptor type 1 knockout or haematopoietic stem cell gene therapy over‐expressing IL‐1Ra reduced gliosis and completely prevented behavioural phenotypes. In conclusion, we demonstrate that IL‐1 drives neuroinflammation, behavioural abnormality and cognitive decline in mucopolysaccharidosis IIIA, highlighting haematopoietic stem cell gene therapy treatment with IL‐1Ra as a potential neuronopathic lysosomal disease treatment.
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Affiliation(s)
- Helen Parker
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Stuart M Ellison
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Rebecca J Holley
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Claire O'Leary
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Aiyin Liao
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Jalal Asadi
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Emily Glover
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Arunabha Ghosh
- Royal Manchester Children's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - Simon Jones
- Royal Manchester Children's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - Fiona L Wilkinson
- Division of Biomedical Sciences, School of Healthcare Science, Manchester Metropolitan University, Manchester, UK.,The Centre for Bioscience, Manchester Metropolitan University, Manchester, UK
| | - David Brough
- Division of Neuroscience & Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Emmanuel Pinteaux
- Division of Neuroscience & Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Hervé Boutin
- Division of Neuroscience & Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK.,Wolfson Molecular Imaging Centre, University of Manchester, Manchester, UK
| | - Brian W Bigger
- Stem Cell and Neurotherapies, Division of Cell Matrix Biology & Regenerative Medicine, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
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15
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Jing X, Behmer ST. Insect Sterol Nutrition: Physiological Mechanisms, Ecology, and Applications. ANNUAL REVIEW OF ENTOMOLOGY 2020; 65:251-271. [PMID: 31600456 DOI: 10.1146/annurev-ento-011019-025017] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Insects, like all eukaryotes, require sterols for structural and metabolic purposes. However, insects, like all arthropods, cannot make sterols. Cholesterol is the dominant tissue sterol for most insects; insect herbivores produce cholesterol by metabolizing phytosterols, but not always with high efficiency. Many insects grow on a mixed-sterol diet, but this ability varies depending on the types and ratio of dietary sterols. Dietary sterol uptake, transport, and metabolism are regulated by several proteins and processes that are relatively conserved across eukaryotes. Sterol requirements also impact insect ecology and behavior. There is potential to exploit insect sterol requirements to (a) control insect pests in agricultural systems and (b) better understand sterol biology, including in humans. We suggest that future studies focus on the genetic mechanism of sterol metabolism and reverse transportation, characterizing sterol distribution and function at the cellular level, the role of bacterial symbionts in sterol metabolism, and interrupting sterol trafficking for pest control.
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Affiliation(s)
- Xiangfeng Jing
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China;
- Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau, Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Spencer T Behmer
- Department of Entomology, Texas A&M University, College Station, Texas 77843, USA;
- Ecology & Evolutionary Biology Graduate Program, Texas A&M University, College Station, Texas 77843, USA
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16
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Takeshima M, Ogihara MH, Kataoka H. Sterol Characteristics in Silkworm Brain and Various Tissues Characterized by Precise Sterol Profiling Using LC-MS/MS. Int J Mol Sci 2019; 20:ijms20194840. [PMID: 31569473 PMCID: PMC6801466 DOI: 10.3390/ijms20194840] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 09/23/2019] [Accepted: 09/26/2019] [Indexed: 12/24/2022] Open
Abstract
Sterols, especially cholesterol (Chl), are fundamental for animal survival. Insects lacking the ability to synthesize Chl are sterol auxotrophic animals and utilize dietary Chl and phytosterols to survive. The sterols obtained from a diet are distributed to the tissues; however, sterol homeostasis in insect tissues remains to be elucidated. This study sought to understand the sterol characteristics of insect tissues through detailed sterol quantification and statistics. The combination of sterol quantification using liquid chromatography tandem mass spectrometry (LC-MS/MS) and principal component analysis (PCA) revealed tissue-specific sterol characteristics in the silkworm, Bombyx mori, a phytophagous insect. We found that insect tissues have tissue-intrinsic sterol profiles. The brain has a unique sterol composition as compared to other tissues—high concentration of Chl and less accumulation of phytosterols. Other tissues also have intrinsic sterol characteristics, which when defined by dietary sterols or Chl metabolites, indicate preference for a sterol and consistently manage their own sterol homeostasis. Though most tissues never change sterol profiles during development, the brain drastically changes its sterol profile at the wandering stage, indicating that it could alter sterol composition in preparation for metamorphosis. These results suggest the existence of tissue- and sterol-specific systems for sterol homeostasis in insects.
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Affiliation(s)
- Mika Takeshima
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
| | - Mari H Ogihara
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
- National Agriculture and Food Research Organization, 2 Ikenodai, Tsukuba, Ibaraki 305-0901, Japan.
| | - Hiroshi Kataoka
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
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17
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Bialistoky T, Manry D, Smith P, Ng C, Kim Y, Zamir S, Moyal V, Kalifa R, Schedl P, Gerlitz O, Deshpande G. Functional analysis of Niemann-Pick disease type C family protein, NPC1a, in Drosophila melanogaster. Development 2019; 146:dev.168427. [PMID: 31092503 DOI: 10.1242/dev.168427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 04/01/2019] [Indexed: 01/20/2023]
Abstract
During embryonic gonad coalescence, primordial germ cells (PGCs) follow a carefully choreographed migratory route circumscribed by guidance signals towards somatic gonadal precursor cells (SGPs). In Drosophila melanogaster, SGP-derived Hedgehog (Hh), which serves as a guidance cue for the PGCs, is potentiated by mesodermally restricted HMGCoA-reductase (Hmgcr) and the ABC transporter Multi-drug-resistant-49 (Mdr49). Given the importance of cholesterol modification in the processing and long-distance transmission of the Hh ligand, we have analyzed the involvement of the Niemann-Pick disease type C-1a (NPC1a) protein, a cholesterol transporter, in germ cell migration and Hedgehog signaling. We show that mesoderm-specific inactivation of Npc1a results in germ cell migration defects. Similar to Mdr49, PGC migration defects in the Npc1a embryos are ameliorated by a cholesterol-rich diet. Consistently, reduction in Npc1a weakens the ability of ectopic HMG Coenzyme A reductase (Hmgcr) to induce germ cell migration defects. Moreover, compromising Npc1a levels influences Hh signaling adversely during wing development, a process that relies upon long-range Hh signaling. Last, doubly heterozygous embryos (Mdr49/Npc1a) display enhanced germ cell migration defects when compared with single mutants (Npc1a/+ or Mdr49/+), supporting cooperative interaction between the two.
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Affiliation(s)
- Tzofia Bialistoky
- Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Diane Manry
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Peyton Smith
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Christopher Ng
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Yunah Kim
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Sol Zamir
- Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Victoria Moyal
- Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Rachel Kalifa
- Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Paul Schedl
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Offer Gerlitz
- Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Girish Deshpande
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
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18
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Deal SL, Yamamoto S. Unraveling Novel Mechanisms of Neurodegeneration Through a Large-Scale Forward Genetic Screen in Drosophila. Front Genet 2019; 9:700. [PMID: 30693015 PMCID: PMC6339878 DOI: 10.3389/fgene.2018.00700] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 12/13/2018] [Indexed: 01/04/2023] Open
Abstract
Neurodegeneration is characterized by progressive loss of neurons. Genetic and environmental factors both contribute to demise of neurons, leading to diverse devastating cognitive and motor disorders, including Alzheimer's and Parkinson's diseases in humans. Over the past few decades, the fruit fly, Drosophila melanogaster, has become an integral tool to understand the molecular, cellular and genetic mechanisms underlying neurodegeneration. Extensive tools and sophisticated technologies allow Drosophila geneticists to identify and study evolutionarily conserved genes that are essential for neural maintenance. In this review, we will focus on a large-scale mosaic forward genetic screen on the fly X-chromosome that led to the identification of a number of essential genes that exhibit neurodegenerative phenotypes when mutated. Most genes identified from this screen are evolutionarily conserved and many have been linked to human diseases with neurological presentations. Systematic electrophysiological and ultrastructural characterization of mutant tissue in the context of the Drosophila visual system, followed by a series of experiments to understand the mechanism of neurodegeneration in each mutant led to the discovery of novel molecular pathways that are required for neuronal integrity. Defects in mitochondrial function, lipid and iron metabolism, protein trafficking and autophagy are recurrent themes, suggesting that insults that eventually lead to neurodegeneration may converge on a set of evolutionarily conserved cellular processes. Insights from these studies have contributed to our understanding of known neurodegenerative diseases such as Leigh syndrome and Friedreich's ataxia and have also led to the identification of new human diseases. By discovering new genes required for neural maintenance in flies and working with clinicians to identify patients with deleterious variants in the orthologous human genes, Drosophila biologists can play an active role in personalized medicine.
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Affiliation(s)
- Samantha L Deal
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, United States
| | - Shinya Yamamoto
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, United States.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
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19
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Tied up: Does altering phosphoinositide-mediated membrane trafficking influence neurodegenerative disease phenotypes? J Genet 2018. [DOI: 10.1007/s12041-018-0961-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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20
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Nadiminti SSP, Kamak M, Koushika SP. Tied up: Does altering phosphoinositide-mediated membrane trafficking influence neurodegenerative disease phenotypes? J Genet 2018; 97:753-771. [PMID: 30027907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Phosphoinositides are a class of membrane lipids that are found on several intracellular compartments and play diverse roles inside cells, such as vesicle formation, protein trafficking, endocytosis etc. Intracellular distribution and levels of phosphoinositides are regulated by enzymes that generate and breakdown these lipids as well as other proteins that associate with phosphoinositides. These events lead to differing levels of specific phosphoinositides on different intracellular compartments. At these intracellular locations, phosphoinositides and their associated proteins, such as Rab GTPases, dynamin and BAR domain-containing proteins, regulate a variety of membrane trafficking pathways. Neurodegenerative phenotypes in disorders such as Parkinson's disease (PD) can arise as a consequence of altered or hampered intracellular trafficking. Altered trafficking can cause proteins such as α-synuclein to aggregate intracellularly. Several trafficking pathways are regulated bymaster regulators such as LRRK2,which is known to regulate the activity of phosphoinositide effector proteins. Perturbing either the levels of phosphoinositides or their interactions with different proteins disrupts intracellular trafficking pathways, contributing to phenotypes often observed in disorders such as Alzheimer's or PDs. Thus, studying phosphoinositide regulation and its role in trafficking can give us a deeper understanding of the contribution of disrupted trafficking to neurodegenerative phenotypes.
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Affiliation(s)
- Sravanthi S P Nadiminti
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai 400 005, India.
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21
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Ueda A, Woods S, McElree I, O'Harrow TCDG, Inman C, Thenuwara S, Aftab M, Iyengar A. Two novel forms of ERG oscillation in Drosophila: age and activity dependence. J Neurogenet 2018; 32:118-126. [PMID: 29688104 DOI: 10.1080/01677063.2018.1461866] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Over an animal's lifespan, neuronal circuits and systems often decline in an inherently heterogeneous fashion. To compare the age-dependent progression of changes in visual behavior with alterations in retinal physiology, we examined phototaxis and electroretinograms (ERGs) in a wild-type D. melanogaster strain (Canton-S) across their lifespan. In aged flies (beyond 50% median lifespan), we found a marked decline in phototaxis, while motor coordination was less disrupted, as indicated by relatively stronger negative geotaxis. These aged flies displayed substantially reduced ERG transient amplitudes while the receptor potentials (RP) remained largely intact. Using a repetitive light flash protocol, we serendipitously discovered two forms of activity-dependent oscillation in the ERG waveforms of young flies: 'light-off' and 'light-on' oscillations. After repeated 500 ms light flashes, light-off oscillations appeared during the ERG off-transients (frequency: 50-120 Hz, amplitude: ∼1 mV). Light-on oscillations (100-200 Hz, ∼0.3 mV) were induced by a series of 50 ms flashes, and were evident during the ERG on-transients. Both forms of oscillation were observed in other strains of D. melanogaster (Oregon-R, Berlin), additional Drosophila species (D. funerbris, D. euronotus, D. hydei, D. americana), and were evoked by a variety of light sources. Both light-off and light-on oscillations were distinct from previously described ERG oscillations in the visual mutant rosA in terms of location within the waveform and frequency. However, within rosA mutants, light-off oscillations, but not light-on oscillations could be recruited by the repetitive light flash protocol. Importantly though, we found that both forms of oscillation were rarely observed in aged flies. Although the physiological bases of these oscillations remain to be elucidated, they may provide important clues to age-related changes in neuronal excitability and synaptic transmission.
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Affiliation(s)
- Atsushi Ueda
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Scott Woods
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Ian McElree
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | | | - Casey Inman
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | | | - Muhammad Aftab
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Atulya Iyengar
- a Department of Biology , University of Iowa , Iowa City , IA , USA
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Reversal of Pathologic Lipid Accumulation in NPC1-Deficient Neurons by Drug-Promoted Release of LAMP1-Coated Lamellar Inclusions. J Neurosci 2017; 36:8012-25. [PMID: 27466344 DOI: 10.1523/jneurosci.0900-16.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/15/2016] [Indexed: 02/05/2023] Open
Abstract
UNLABELLED Aging and pathologic conditions cause intracellular aggregation of macromolecules and the dysfunction and degeneration of neurons, but the mechanisms are largely unknown. Prime examples are lysosomal storage disorders such as Niemann-Pick type C (NPC) disease, where defects in the endosomal-lysosomal protein NPC1 or NPC2 cause intracellular accumulation of unesterified cholesterol and other lipids leading to neurodegeneration and fatal neurovisceral symptoms. Here, we investigated the impact of NPC1 deficiency on rodent neurons using pharmacologic and genetic models of the disease. Improved ultrastructural detection of lipids and correlative light and electron microscopy identified lamellar inclusions as the subcellular site of cholesterol accumulation in neurons with impaired NPC1 activity. Immunogold labeling combined with transmission electron microscopy revealed the presence of CD63 on internal lamellae and of LAMP1 on the membrane surrounding the inclusions, indicating their origins from intraluminal vesicles of late endosomes and of a lysosomal compartment, respectively. Lamellar inclusions contained cell-intrinsic cholesterol and surface-labeled GM1, indicating the incorporation of plasma membrane components. Scanning electron microscopy revealed that the therapeutic drug candidate β-cyclodextrin induces the subplasmalemmal location of lamellar inclusions and their subsequent release to the extracellular space. In parallel, β-cyclodextrin mediated the NPC1-independent redistribution of cholesterol within neurons and thereby abolished a deleterious cycle of enhanced cholesterol synthesis and its intracellular accumulation, which was indicated by neuron-specific transcript analysis. Our study provides new mechanistic insight into the pathologic aggregation of macromolecules in neurons and suggests exocytosis as cellular target for its therapeutic reversal. SIGNIFICANCE STATEMENT Many neurodegenerative diseases involve pathologic accumulation of molecules within neurons, but the subcellular location and the cellular impact are often unknown and therapeutic approaches lacking. We investigated these questions in the lysosomal storage disorder Niemann-Pick type C (NPC), where a defect in intracellular cholesterol transport causes loss of neurons and fatal neurovisceral symptoms. Here, we identify lamellar inclusions as the subcellular site of lipid accumulation in neurons, we uncover a vicious cycle of cholesterol synthesis and accretion, which may cause gradual neurodegeneration, and we reveal how β-cyclodextrin, a potential therapeutic drug, reverts these changes. Our study provides new mechanistic insight in NPC disease and uncovers new targets for therapeutic approaches.
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Peters M, Katz B, Lev S, Zaguri R, Gutorov R, Minke B. Depletion of Membrane Cholesterol Suppresses Drosophila Transient Receptor Potential-Like (TRPL) Channel Activity. CURRENT TOPICS IN MEMBRANES 2017; 80:233-254. [DOI: 10.1016/bs.ctm.2017.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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24
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Hindle SJ, Hebbar S, Schwudke D, Elliott CJH, Sweeney ST. A saposin deficiency model in Drosophila: Lysosomal storage, progressive neurodegeneration and sensory physiological decline. Neurobiol Dis 2016; 98:77-87. [PMID: 27913291 PMCID: PMC5319729 DOI: 10.1016/j.nbd.2016.11.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/10/2016] [Accepted: 11/25/2016] [Indexed: 02/06/2023] Open
Abstract
Saposin deficiency is a childhood neurodegenerative lysosomal storage disorder (LSD) that can cause premature death within three months of life. Saposins are activator proteins that promote the function of lysosomal hydrolases that mediate the degradation of sphingolipids. There are four saposin proteins in humans, which are encoded by the prosaposin gene. Mutations causing an absence or impaired function of individual saposins or the whole prosaposin gene lead to distinct LSDs due to the storage of different classes of sphingolipids. The pathological events leading to neuronal dysfunction induced by lysosomal storage of sphingolipids are as yet poorly defined. We have generated and characterised a Drosophila model of saposin deficiency that shows striking similarities to the human diseases. Drosophila saposin-related (dSap-r) mutants show a reduced longevity, progressive neurodegeneration, lysosomal storage, dramatic swelling of neuronal soma, perturbations in sphingolipid catabolism, and sensory physiological deterioration. Our data suggests a genetic interaction with a calcium exchanger (Calx) pointing to a possible calcium homeostasis deficit in dSap-r mutants. Together these findings support the use of dSap-r mutants in advancing our understanding of the cellular pathology implicated in saposin deficiency and related LSDs. Drosophila model of PSD recapitulates neurodegenerative phenotype of human PSD. Preferential degeneration of sensory regions correlates with loss of sensory function. Sphingosine levels rise with age with an imbalance in sphingosine/ceramide ratios. Genetic interaction with the Na +/Ca + exchanger points to a calcium regulation deficit.
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Affiliation(s)
| | - Sarita Hebbar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, Karnataka 560065, India
| | - Dominik Schwudke
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, Karnataka 560065, India
| | | | - Sean T Sweeney
- Department of Biology, University of York, York YO10 5DD, UK.
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25
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Sivachenko A, Gordon HB, Kimball SS, Gavin EJ, Bonkowsky JL, Letsou A. Neurodegeneration in a Drosophila model of adrenoleukodystrophy: the roles of the Bubblegum and Double bubble acyl-CoA synthetases. Dis Model Mech 2016; 9:377-87. [PMID: 26893370 PMCID: PMC4852500 DOI: 10.1242/dmm.022244] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 02/17/2016] [Indexed: 12/21/2022] Open
Abstract
Debilitating neurodegenerative conditions with metabolic origins affect millions of individuals worldwide. Still, for most of these neurometabolic disorders there are neither cures nor disease-modifying therapies, and novel animal models are needed for elucidation of disease pathology and identification of potential therapeutic agents. To date, metabolic neurodegenerative disease has been modeled in animals with only limited success, in part because existing models constitute analyses of single mutants and have thus overlooked potential redundancy within metabolic gene pathways associated with disease. Here, we present the first analysis of a very-long-chain acyl-CoA synthetase (ACS) double mutant. We show that the Drosophila bubblegum(bgm) and double bubble(dbb) genes have overlapping functions, and that the consequences of double knockout of both bubblegum and double bubble in the fly brain are profound, affecting behavior and brain morphology, and providing the best paradigm to date for an animal model of adrenoleukodystrophy (ALD), a fatal childhood neurodegenerative disease associated with the accumulation of very-long-chain fatty acids. Using this more fully penetrant model of disease to interrogate brain morphology at the level of electron microscopy, we show that dysregulation of fatty acid metabolism via disruption of ACS function in vivois causal of neurodegenerative pathologies that are evident in both neuronal cells and their supporting cell populations, and leads ultimately to lytic cell death in affected areas of the brain. Finally, in an extension of our model system to the study of human disease, we describe our identification of an individual with leukodystrophy who harbors a rare mutation in SLC27a6(encoding a very-long-chain ACS), a human homolog of bgm and dbb.
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Affiliation(s)
- Anna Sivachenko
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Hannah B Gordon
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Suzanne S Kimball
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Erin J Gavin
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Joshua L Bonkowsky
- Department of Pediatrics, University of Utah, Salt Lake City, UT 84112, USA
| | - Anthea Letsou
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
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26
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Shahzad A, Siddiqui S, Bano A. Rhizoremediation of petroleum hydrocarbon, prospects and future. RSC Adv 2016. [DOI: 10.1039/c6ra12458e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Oil refineries generate several tones of oily waste which is dumped in an open pit within the vicinity of oil field.
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Affiliation(s)
- Asim Shahzad
- Mohi-Ud-Din Islamic University
- Pakistan
- Department of Bio Sciences
- University of Wah
- Wah Cannt
| | - Samina Siddiqui
- National Center for Excellence in Geology
- University of Peshawar
- Pakistan
| | - Asghari Bano
- Department of Bio Sciences
- University of Wah
- Wah Cannt
- Pakistan
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27
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28
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Yan X, Ma L, Hovakimyan M, Lukas J, Wree A, Frank M, Guthoff R, Rolfs A, Witt M, Luo J. Defects in the retina of Niemann-pick type C 1 mutant mice. BMC Neurosci 2014; 15:126. [PMID: 25472750 PMCID: PMC4267119 DOI: 10.1186/s12868-014-0126-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 11/12/2014] [Indexed: 11/24/2022] Open
Abstract
Background Niemann-Pick type C1 (NPC1) disease is an inherited lysosomal storage disease caused by mutation of the Npc1 gene, resulting in a progressive accumulation of unesterified cholesterol and glycolipids in lysosomes of multiple tissues and leading to neurodegeneration and other disease. In Npc1 mutant mice, retinal degeneration including impaired visual function, lipofuscin accumulation in the pigment epithelium and ganglion cells as well as photoreceptor defects has been found. However, the pathologies of other individual cell types of the retina in Npc1 mutant mice are still not fully clear. We hypothesized that horizontal cells, amacrine cells, bipolar cells and glial cells are also affected in the retina of Npc1 mutant mice. Results Immunohistochemistry and electron microscopy were used to investigate pathologies of ganglion cells, horizontal cells, amacrine cells, bipolar cells, and optic nerves as well as altered activity of glial cells in Npc1 mutant mice. Electron microscopy reveals that electron-dense inclusions are generally accumulated in ganglion cells, bipolar cells, Müller cells, and in the optic nerve. Furthermore, abnormal arborisation and ectopic processes of horizontal and amacrine cells as well as defective bipolar cells are observed by immunohistochemistry for specific cellular markers. Furthermore, hyperactivity of glial cells, including astrocytes, microglial cells, and Müller cells, is also revealed. Conclusions Our data extend previous findings to show multiple defects in the retina of Npc1 mutant mice, suggesting an important role of Npc1 protein in the normal function of the retina. Electronic supplementary material The online version of this article (doi:10.1186/s12868-014-0126-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xin Yan
- Albrecht-Kossel-Institute for Neuroregeneration, Rostock University Medical Center, Gehlsheimer Strasse 20, D-18147, Rostock, Germany.
| | - Lucy Ma
- Albrecht-Kossel-Institute for Neuroregeneration, Rostock University Medical Center, Gehlsheimer Strasse 20, D-18147, Rostock, Germany.
| | - Marina Hovakimyan
- Institute for Biomedical Engineering, Rostock University Medical Center, F.-Barnewitz Strasse 4, D-18119, Rostock, Germany.
| | - Jan Lukas
- Albrecht-Kossel-Institute for Neuroregeneration, Rostock University Medical Center, Gehlsheimer Strasse 20, D-18147, Rostock, Germany.
| | - Andreas Wree
- Department of Anatomy, Rostock University Medical Center, Gertrudenstrsse 9, D-18055, Rostock, Germany.
| | - Marcus Frank
- Electron Microscopy Center, Rostock University Medical Center, Strempelstr. 14, D-18057, Rostock, Germany.
| | - Rudolf Guthoff
- Department of Ophthalmology, Rostock University Medical Center, Doberaner Strasse 140, D-18057, Rostock, Germany.
| | - Arndt Rolfs
- Albrecht-Kossel-Institute for Neuroregeneration, Rostock University Medical Center, Gehlsheimer Strasse 20, D-18147, Rostock, Germany.
| | - Martin Witt
- Department of Anatomy, Rostock University Medical Center, Gertrudenstrsse 9, D-18055, Rostock, Germany.
| | - Jiankai Luo
- Albrecht-Kossel-Institute for Neuroregeneration, Rostock University Medical Center, Gehlsheimer Strasse 20, D-18147, Rostock, Germany.
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29
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Buard I, Pfrieger FW. Relevance of neuronal and glial NPC1 for synaptic input to cerebellar Purkinje cells. Mol Cell Neurosci 2014; 61:65-71. [DOI: 10.1016/j.mcn.2014.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 05/27/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022] Open
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Cholesterol in the retina: the best is yet to come. Prog Retin Eye Res 2014; 41:64-89. [PMID: 24704580 DOI: 10.1016/j.preteyeres.2014.03.002] [Citation(s) in RCA: 192] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 03/13/2014] [Accepted: 03/17/2014] [Indexed: 01/09/2023]
Abstract
Historically understudied, cholesterol in the retina is receiving more attention now because of genetic studies showing that several cholesterol-related genes are risk factors for age-related macular degeneration (AMD) and because of eye pathology studies showing high cholesterol content of drusen, aging Bruch's membrane, and newly found subretinal lesions. The challenge before us is determining how the cholesterol-AMD link is realized. Meeting this challenge will require an excellent understanding these genes' roles in retinal physiology and how chorioretinal cholesterol is maintained. In the first half of this review, we will succinctly summarize physico-chemical properties of cholesterol, its distribution in the human body, general principles of maintenance and metabolism, and differences in cholesterol handling in human and mouse that impact on experimental approaches. This information will provide a backdrop to the second part of the review focusing on unique aspects of chorioretinal cholesterol homeostasis, aging in Bruch's membrane, cholesterol in AMD lesions, a model for lesion biogenesis, a model for macular vulnerability based on vascular biology, and alignment of AMD-related genes and pathobiology using cholesterol and an atherosclerosis-like progression as unifying features. We conclude with recommendations for the most important research steps we can take towards delineating the cholesterol-AMD link.
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31
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Fourgeux C, Martine L, Acar N, Bron AM, Creuzot-Garcher CP, Bretillon L. In vivo consequences of cholesterol-24S-hydroxylase (CYP46A1) inhibition by voriconazole on cholesterol homeostasis and function in the rat retina. Biochem Biophys Res Commun 2014; 446:775-81. [DOI: 10.1016/j.bbrc.2014.01.118] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 01/23/2014] [Indexed: 01/06/2023]
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32
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Vance JE, Karten B. Niemann-Pick C disease and mobilization of lysosomal cholesterol by cyclodextrin. J Lipid Res 2014; 55:1609-21. [PMID: 24664998 DOI: 10.1194/jlr.r047837] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Indexed: 12/31/2022] Open
Abstract
Niemann-Pick type C (NPC) disease is a lysosomal storage disease in which endocytosed cholesterol becomes sequestered in late endosomes/lysosomes (LEs/Ls) because of mutations in either the NPC1 or NPC2 gene. Mutations in either of these genes can lead to impaired functions of the NPC1 or NPC2 proteins and progressive neurodegeneration as well as liver and lung disease. NPC1 is a polytopic protein of the LE/L limiting membrane, whereas NPC2 is a soluble protein in the LE/L lumen. These two proteins act in tandem and promote the export of cholesterol from LEs/Ls. Consequently, a defect in either NPC1 or NPC2 causes cholesterol accumulation in LEs/Ls. In this review, we summarize the molecular mechanisms leading to NPC disease, particularly in the CNS. Recent exciting data on the mechanism by which the cholesterol-sequestering agent cyclodextrin can bypass the functions of NPC1 and NPC2 in the LEs/Ls, and mobilize cholesterol from LEs/Ls, will be highlighted. Moreover, the possible use of cyclodextrin as a valuable therapeutic agent for treatment of NPC patients will be considered.
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Affiliation(s)
- Jean E Vance
- The Group on Molecular and Cell Biology of Lipids and Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Barbara Karten
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS, Canada
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33
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Moskalev A, Shaposhnikov M, Snezhkina A, Kogan V, Plyusnina E, Peregudova D, Melnikova N, Uroshlev L, Mylnikov S, Dmitriev A, Plusnin S, Fedichev P, Kudryavtseva A. Mining gene expression data for pollutants (dioxin, toluene, formaldehyde) and low dose of gamma-irradiation. PLoS One 2014; 9:e86051. [PMID: 24475070 PMCID: PMC3901678 DOI: 10.1371/journal.pone.0086051] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 12/04/2013] [Indexed: 12/28/2022] Open
Abstract
General and specific effects of molecular genetic responses to adverse environmental factors are not well understood. This study examines genome-wide gene expression profiles of Drosophila melanogaster in response to ionizing radiation, formaldehyde, toluene, and 2,3,7,8-tetrachlorodibenzo-p-dioxin. We performed RNA-seq analysis on 25,415 transcripts to measure the change in gene expression in males and females separately. An analysis of the genes unique to each treatment yielded a list of genes as a gene expression signature. In the case of radiation exposure, both sexes exhibited a reproducible increase in their expression of the transcription factors sugarbabe and tramtrack. The influence of dioxin up-regulated metabolic genes, such as anachronism, CG16727, and several genes with unknown function. Toluene activated a gene involved in the response to the toxins, Cyp12d1-p; the transcription factor Fer3's gene; the metabolic genes CG2065, CG30427, and CG34447; and the genes Spn28Da and Spn3, which are responsible for reproduction and immunity. All significantly differentially expressed genes, including those shared among the stressors, can be divided into gene groups using Gene Ontology Biological Process identifiers. These gene groups are related to defense response, biological regulation, the cell cycle, metabolic process, and circadian rhythms. KEGG molecular pathway analysis revealed alteration of the Notch signaling pathway, TGF-beta signaling pathway, proteasome, basal transcription factors, nucleotide excision repair, Jak-STAT signaling pathway, circadian rhythm, Hippo signaling pathway, mTOR signaling pathway, ribosome, mismatch repair, RNA polymerase, mRNA surveillance pathway, Hedgehog signaling pathway, and DNA replication genes. Females and, to a lesser extent, males actively metabolize xenobiotics by the action of cytochrome P450 when under the influence of dioxin and toluene. Finally, in this work we obtained gene expression signatures pollutants (dioxin, toluene), low dose of gamma-irradiation and common molecular pathways for different kind of stressors.
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Affiliation(s)
- Alexey Moskalev
- Laboratory of Molecular Radiobiology and Gerontology, Institute of Biology of Komi Science Center of RAS, Syktyvkar, Russia
- Ecological Department, Syktyvkar State University, Syktyvkar, Russia
- Laboratory of Genetics of Aging and Longevity, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Mikhail Shaposhnikov
- Laboratory of Molecular Radiobiology and Gerontology, Institute of Biology of Komi Science Center of RAS, Syktyvkar, Russia
- Ecological Department, Syktyvkar State University, Syktyvkar, Russia
| | - Anastasia Snezhkina
- Group of Postgenomic Studies, Engelhardt Institute of Molecular Biology of RAS, Moscow, Russia
| | - Valeria Kogan
- Laboratory of Genetics of Aging and Longevity, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Quantum Pharmaceuticals, Moscow, Russia
| | - Ekaterina Plyusnina
- Laboratory of Molecular Radiobiology and Gerontology, Institute of Biology of Komi Science Center of RAS, Syktyvkar, Russia
- Ecological Department, Syktyvkar State University, Syktyvkar, Russia
| | - Darya Peregudova
- Laboratory of Molecular Radiobiology and Gerontology, Institute of Biology of Komi Science Center of RAS, Syktyvkar, Russia
| | - Nataliya Melnikova
- Group of Postgenomic Studies, Engelhardt Institute of Molecular Biology of RAS, Moscow, Russia
| | - Leonid Uroshlev
- Group of Postgenomic Studies, Engelhardt Institute of Molecular Biology of RAS, Moscow, Russia
- Department of Computational Systems Biology, Vavilov Institute of General Genetics, Moscow, Russia
| | - Sergey Mylnikov
- Department of Genetics, St. Petersburg State University, St. Petersburg, Russia
| | - Alexey Dmitriev
- Group of Postgenomic Studies, Engelhardt Institute of Molecular Biology of RAS, Moscow, Russia
| | - Sergey Plusnin
- Laboratory of Molecular Radiobiology and Gerontology, Institute of Biology of Komi Science Center of RAS, Syktyvkar, Russia
- Ecological Department, Syktyvkar State University, Syktyvkar, Russia
| | - Peter Fedichev
- Laboratory of Genetics of Aging and Longevity, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Quantum Pharmaceuticals, Moscow, Russia
| | - Anna Kudryavtseva
- Group of Postgenomic Studies, Engelhardt Institute of Molecular Biology of RAS, Moscow, Russia
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34
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Dason JS, Charlton MP. A novel extraction protocol to probe the role of cholesterol in synaptic vesicle recycling. Methods Mol Biol 2014; 1174:361-373. [PMID: 24947395 DOI: 10.1007/978-1-4939-0944-5_25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Cholesterol helps to stabilize membrane fluidity and many membrane proteins interact with cholesterol and are functionally clustered in cholesterol rich "rafts." Synaptic vesicle (SV) membranes are enriched in cholesterol in comparison to other organelles. Attempts to study the function of this high cholesterol content have been hampered by the inability to extract cholesterol from SVs in live presynaptic terminals. Here, we describe a method to extract vesicular cholesterol using a temperature-sensitive Drosophila dynamin mutant, shibire-ts1 (shi), to trap SVs on the plasma membrane. Trapped SVs are more accessible to cholesterol extraction by the cholesterol chelator, methyl-β-cyclodextrin (MβCD). This method can likely be extended to extract other lipids from SVs and could also be used to add lipids. We speculate that this method could be used on mammalian preparations in conjunction with dynamin inhibitors.
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Affiliation(s)
- Jeffrey S Dason
- Department of Physiology, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, ON, Canada, M5S1A8,
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35
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Movassagh M, Mudvari P, Kokkinaki M, Edwards NJ, Golestaneh N, Horvath A. Analysis for co-occurring sequence features identifies link between common synonymous variant and an early-terminated NPC1 isoform. J Clin Bioinforma 2014. [DOI: 10.1186/2043-9113-4-14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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36
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Miller JD, Ganat YM, Kishinevsky S, Bowman RL, Liu B, Tu EY, Mandal P, Vera E, Shim JW, Kriks S, Taldone T, Fusaki N, Tomishima MJ, Krainc D, Milner TA, Rossi DJ, Studer L. Human iPSC-based modeling of late-onset disease via progerin-induced aging. Cell Stem Cell 2013; 13:691-705. [PMID: 24315443 PMCID: PMC4153390 DOI: 10.1016/j.stem.2013.11.006] [Citation(s) in RCA: 534] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 09/27/2013] [Accepted: 11/05/2013] [Indexed: 12/15/2022]
Abstract
Reprogramming somatic cells to induced pluripotent stem cells (iPSCs) resets their identity back to an embryonic age and, thus, presents a significant hurdle for modeling late-onset disorders. In this study, we describe a strategy for inducing aging-related features in human iPSC-derived lineages and apply it to the modeling of Parkinson's disease (PD). Our approach involves expression of progerin, a truncated form of lamin A associated with premature aging. We found that expression of progerin in iPSC-derived fibroblasts and neurons induces multiple aging-related markers and characteristics, including dopamine-specific phenotypes such as neuromelanin accumulation. Induced aging in PD iPSC-derived dopamine neurons revealed disease phenotypes that require both aging and genetic susceptibility, such as pronounced dendrite degeneration, progressive loss of tyrosine hydroxylase (TH) expression, and enlarged mitochondria or Lewy-body-precursor inclusions. Thus, our study suggests that progerin-induced aging can be used to reveal late-onset age-related disease features in hiPSC-based disease models.
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Affiliation(s)
- Justine D. Miller
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Gerstner Sloan-Kettering Graduate School, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Yosif M. Ganat
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Sarah Kishinevsky
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Robert L. Bowman
- Gerstner Sloan-Kettering Graduate School, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Cancer Biology and Genetics Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Becky Liu
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Edmund Y. Tu
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Pankaj Mandal
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, MA 02115, USA
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
| | - Elsa Vera
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Jae-won Shim
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Sonja Kriks
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Tony Taldone
- Molecular Pharmacology & Chemistry, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Noemi Fusaki
- DNAVEC Corporation, Tsukuba, Ibaraki 300-2611, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Mark J. Tomishima
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
| | - Dimitri Krainc
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Massachusetts General Institute for Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Teresa A. Milner
- Brain and Mind Research Institute, Weill Cornell Medical College, 407 East 61st Street, New York, NY 10065, USA
- Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, 1230 York Ave, New York, NY 10065, USA
| | - Derrick J. Rossi
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, Boston, MA 02115, USA
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
| | - Lorenz Studer
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
- Developmental Biology Program, Sloan-Kettering Institute for Cancer Research, 1275 York Ave, New York, NY 10065, USA
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Mechanism of inflammation in age-related macular degeneration: an up-to-date on genetic landmarks. Mediators Inflamm 2013; 2013:435607. [PMID: 24369445 PMCID: PMC3863457 DOI: 10.1155/2013/435607] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 09/28/2013] [Indexed: 12/13/2022] Open
Abstract
Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment among people over 50 years of age, accounting for up to 50% of all cases of legal blindness in Western countries. Although the aging represents the main determinant of AMD, it must be considered a multifaceted disease caused by interactions among environmental risk factors and genetic backgrounds. Mounting evidence and/or arguments document the crucial role of inflammation and immune-mediated processes in the pathogenesis of AMD. Proinflammatory effects secondary to chronic inflammation (e.g., alternative complement activation) and heterogeneous types of oxidative stress (e.g., impaired cholesterol homeostasis) can result in degenerative damages at the level of crucial macular structures, that is photoreceptors, retinal pigment epithelium, and Bruch's membrane. In the most recent years, the association of AMD with genes, directly or indirectly, involved in immunoinflammatory pathways is increasingly becoming an essential core for AMD knowledge. Starting from the key basic-research notions detectable at the root of AMD pathogenesis, the present up-to-date paper reviews the best-known and/or the most attractive genetic findings linked to the mechanisms of inflammation of this complex disease.
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Lopez ME, Scott MP. Genetic dissection of a cell-autonomous neurodegenerative disorder: lessons learned from mouse models of Niemann-Pick disease type C. Dis Model Mech 2013; 6:1089-100. [PMID: 23907005 PMCID: PMC3759329 DOI: 10.1242/dmm.012385] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Understanding neurodegenerative disease progression and its treatment requires the systematic characterization and manipulation of relevant cell types and molecular pathways. The neurodegenerative lysosomal storage disorder Niemann-Pick disease type C (NPC) is highly amenable to genetic approaches that allow exploration of the disease biology at the organismal, cellular and molecular level. Although NPC is a rare disease, genetic analysis of the associated neuropathology promises to provide insight into the logic of disease neural circuitry, selective neuron vulnerability and neural-glial interactions. The ability to control the disorder cell-autonomously and in naturally occurring spontaneous animal models that recapitulate many aspects of the human disease allows for an unparalleled dissection of the disease neurobiology in vivo. Here, we review progress in mouse-model-based studies of NPC disease, specifically focusing on the subtype that is caused by a deficiency in NPC1, a sterol-binding late endosomal membrane protein involved in lipid trafficking. We also discuss recent findings and future directions in NPC disease research that are pertinent to understanding the cellular and molecular mechanisms underlying neurodegeneration in general.
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Affiliation(s)
- Manuel E Lopez
- Departments of Developmental Biology, Genetics, and Bioengineering, Howard Hughes Medical Institute, Stanford University School of Medicine, Clark Center W200, 318 Campus Drive, Stanford, CA 94305-5439, USA
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van Bon BWM, Oortveld MAW, Nijtmans LG, Fenckova M, Nijhof B, Besseling J, Vos M, Kramer JM, de Leeuw N, Castells-Nobau A, Asztalos L, Viragh E, Ruiter M, Hofmann F, Eshuis L, Collavin L, Huynen MA, Asztalos Z, Verstreken P, Rodenburg RJ, Smeitink JA, de Vries BBA, Schenck A. CEP89 is required for mitochondrial metabolism and neuronal function in man and fly. Hum Mol Genet 2013; 22:3138-51. [PMID: 23575228 DOI: 10.1093/hmg/ddt170] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
It is estimated that the human mitochondrial proteome consists of 1000-1500 distinct proteins. The majority of these support the various biochemical pathways that are active in these organelles. Individuals with an oxidative phosphorylation disorder of unknown cause provide a unique opportunity to identify novel genes implicated in mitochondrial biology. We identified a homozygous deletion of CEP89 in a patient with isolated complex IV deficiency, intellectual disability and multisystemic problems. CEP89 is a ubiquitously expressed and highly conserved gene of unknown function. Immunocytochemistry and cellular fractionation experiments showed that CEP89 is present both in the cytosol and in the mitochondrial intermembrane space. Furthermore, we ascertained in vitro that downregulation of CEP89 resulted in a severe decrease in complex IV in-gel activity and altered mobility, suggesting that the complex is aberrantly formed. Two-dimensional BN-SDS gel analysis revealed that CEP89 associates with a high-molecular weight complex. Together, these data confirm a role for CEP89 in mitochondrial metabolism. In addition, we modeled CEP89 loss of function in Drosophila. Ubiquitous knockdown of fly Cep89 decreased complex IV activity and resulted in complete lethality. Furthermore, Cep89 is required for mitochondrial integrity, membrane depolarization and synaptic transmission of photoreceptor neurons, and for (sub)synaptic organization of the larval neuromuscular junction. Finally, we tested neuronal Cep89 knockdown flies in the light-off jump reflex habituation assay, which revealed its role in learning. We conclude that CEP89 proteins play an important role in mitochondrial metabolism, especially complex IV activity, and are required for neuronal and cognitive function across evolution.
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Affiliation(s)
- Bregje W M van Bon
- Department of Human Genetics, Radboud University Medical Centre, 6500 HB, Nijmegen, The Netherlands
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40
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Liu Z, Huang X. Lipid metabolism in Drosophila: development and disease. Acta Biochim Biophys Sin (Shanghai) 2013; 45:44-50. [PMID: 23257293 DOI: 10.1093/abbs/gms105] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Proteins, nucleic acids, and lipids are three major components of the cell. Despite a few basic metabolic pathways, we know very little about lipids, compared with the explosion of knowledge about proteins and nucleic acids. How many different forms of lipids are there? What are the in vivo functions of individual lipid? How does lipid metabolism contribute to normal development and human health? Many of these questions remain unanswered. For over a century, the fruit fly Drosophila melanogaster has been used as a model organism to study basic biological questions. In recent years, increasing evidences proved that Drosophila models are highly valuable for lipid metabolism and energy homeostasis researches. Some recent progresses of lipid metabolic regulation during Drosophila development and in Drosophila models of human diseases will be discussed in this review.
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Affiliation(s)
- Zhonghua Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
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41
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Quantitative proteomic analysis of Niemann-Pick disease, type C1 cerebellum identifies protein biomarkers and provides pathological insight. PLoS One 2012; 7:e47845. [PMID: 23144710 PMCID: PMC3483225 DOI: 10.1371/journal.pone.0047845] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 09/21/2012] [Indexed: 01/24/2023] Open
Abstract
Niemann-Pick disease, type C1 (NPC1) is a fatal, neurodegenerative disorder for which there is no definitive therapy. In NPC1, a pathological cascade including neuroinflammation, oxidative stress and neuronal apoptosis likely contribute to the clinical phenotype. While the genetic cause of NPC1 is known, we sought to gain a further understanding into the pathophysiology by identifying differentially expressed proteins in Npc1 mutant mouse cerebella. Using two-dimensional gel electrophoresis and mass spectrometry, 77 differentially expressed proteins were identified in Npc1 mutant mice cerebella compared to controls. These include proteins involved in glucose metabolism, detoxification/oxidative stress and Alzheimer disease-related proteins. Furthermore, members of the fatty acid binding protein family, including FABP3, FABP5 and FABP7, were found to have altered expression in the Npc1 mutant cerebellum relative to control. Translating our findings from the murine model to patients, we confirm altered expression of glutathione s-transferase α, superoxide dismutase, and FABP3 in cerebrospinal fluid of NPC1 patients relative to pediatric controls. A subset of NPC1 patients on miglustat, a glycosphingolipid synthesis inhibitor, showed significantly decreased levels of FABP3 compared to patients not on miglustat therapy. This study provides an initial report of dysregulated proteins in NPC1 which will assist with further investigation of NPC1 pathology and facilitate implementation of therapeutic trials.
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42
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Shi XZ, Zhong X, Yu XQ. Drosophila melanogaster NPC2 proteins bind bacterial cell wall components and may function in immune signal pathways. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2012; 42:545-56. [PMID: 22580186 PMCID: PMC3358802 DOI: 10.1016/j.ibmb.2012.04.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 03/22/2012] [Accepted: 04/13/2012] [Indexed: 05/14/2023]
Abstract
ML (MD-2 (myeloid differentiation factor-2)-related Lipid-recognition) is a conserved domain identified in MD-2, MD-1, NPC2 (Niemann-Pick disease type C2), and mite major allergen protein from animals, plants, and fungi. Vertebrate members of the ML family proteins, such as NPC2 and MD-2, play important roles in lipid metabolism and immune signaling pathway. MD-2 is an essential co-receptor in the lipopolysaccharide (LPS)/Toll-like receptor 4 (TLR4) signaling pathway. Insects contain multiple ML genes, arbitrarily named md-2- or npc2-like genes. However, whether insect ML genes have functions similar to vertebrate md-2 is unknown. In Drosophila melanogaster, there are eight npc2 genes (npc2a-h), and they can be further divided into three subgroups based on the numbers of cysteine residues (6, 7 and 8 Cys) in the mature proteins. The purpose of this study is to investigate whether any Drosophila npc2 genes may have functions in immune signaling pathways. We chose npc2a, npc2e and npc2h genes representing the three subgroups for this study. We showed that recombinant NPC2a, NPC2e and NPC2h not only bound to LPS and lipid A, but also bound to peptidoglycan (PG) and lipoteichoic acid (LTA), a property that has not been reported previously for vertebrate NPC2 or MD-2. More importantly, we showed that over-expression of NPC2a and NPC2e activated diptericin promoter reporter in S2 cells stimulated by PG, suggesting that NPC2e and NPC2a may play a role in the immune deficiency (Imd) pathway. This is the first in vitro study about NPC2 proteins in innate immunity of D. melanogaster.
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Affiliation(s)
| | | | - Xiao-Qiang Yu
- Send correspondence to: Xiao-Qiang Yu, PhD, Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, Telephone: (816)-235-6379, Fax: (816)-235-1503,
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Zheng W, Reem RE, Omarova S, Huang S, DiPatre PL, Charvet CD, Curcio CA, Pikuleva IA. Spatial distribution of the pathways of cholesterol homeostasis in human retina. PLoS One 2012; 7:e37926. [PMID: 22629470 PMCID: PMC3358296 DOI: 10.1371/journal.pone.0037926] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 04/30/2012] [Indexed: 01/25/2023] Open
Abstract
Background The retina is a light-sensitive tissue lining the inner surface of the eye and one of the few human organs whose cholesterol maintenance is still poorly understood. Challenges in studies of the retina include its complex multicellular and multilayered structure; unique cell types and functions; and specific physico-chemical environment. Methodology/Principal Findings We isolated specimens of the neural retina (NR) and underlying retinal pigment epithelium (RPE)/choroid from six deceased human donors and evaluated them for expression of genes and proteins representing the major pathways of cholesterol input, output and regulation. Eighty-four genes were studied by PCR array, 16 genes were assessed by quantitative real time PCR, and 13 proteins were characterized by immunohistochemistry. Cholesterol distribution among different retinal layers was analyzed as well by histochemical staining with filipin. Our major findings pertain to two adjacent retinal layers: the photoreceptor outer segments of NR and the RPE. We demonstrate that in the photoreceptor outer segments, cholesterol biosynthesis, catabolism and regulation via LXR and SREBP are weak or absent and cholesterol content is the lowest of all retinal layers. Cholesterol maintenance in the RPE is different, yet the gene expression also does not appear to be regulated by the SREBPs and varies significantly among different individuals. Conclusions/Significance This comprehensive investigation provides important insights into the relationship and spatial distribution of different pathways of cholesterol input, output and regulation in the NR-RPE region. The data obtained are important for deciphering the putative link between cholesterol and age-related macular degeneration, a major cause of irreversible vision loss in the elderly.
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Affiliation(s)
- Wenchao Zheng
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Rachel E. Reem
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Saida Omarova
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Suber Huang
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
- University Hospitals, Cleveland, Ohio, United States of America
| | - Pier Luigi DiPatre
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Casey D. Charvet
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Christine A. Curcio
- Department of Ophthalmology, University of Alabama, Birmingham, Alabama, United States of America
| | - Irina A. Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, United States of America
- * E-mail:
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44
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Seo Y, Yang SR, Kim HS, Yu KR, Shin Y, Kang SK, Kang KS. JNK Activation by Up-Regulation of iNOS on Cholesterol Accumulation Limits Neurogenesis and Induces Region-Specific DNA Damage Responses in the Subventricular Zone of NPC Mice. Antioxid Redox Signal 2012:120410100912001. [PMID: 22384812 DOI: 10.1089/ars.2011.4301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Abstract Aims: We explore the region-specific impact of nitric oxide (NO) on adult neural stem cell (aNSC) niches with regard to neurogenesis and NSC damage and investigate the underlying mechanisms in Niemann-Pick disease type C (NPC) mice. Results: Among the two anatomical stem-cell niches of the brain, subventricular zone (SVZ)-derived aNSCs enhanced c-Jun N-terminal kinase (JNK) activity because of excessive NO production by the cholesterol accumulation. Activated JNK interacts with γH2AX, a marker for DNA damage; however, almost none of the aNSCs in the dentate gyrus (DG) showed either JNK signaling activation or abundant DNA damage. SVZ-derived aNSCs were protected from DNA damage by the treatment of Nω-nitro-L-arginine methyl ester (L-NAME), a NO synthase (NOS) inhibitor, both in vitro and in vivo. We also observed that U18666A, an inducer of cholesterol accumulation, increased inducible NOS expression, JNK activation, and DNA damage in the wild type (WT)-aNSCs. Interestingly, we found that endogenous cholesterol efflux transporters and their regulator were less activated in the SVZ than in the DG, in both WT and NPC mice. This result explains the high vulnerability of SVZ-derived aNSCs to the cholesterol imbalance as observed in NPC mice. Innovation and Conclusion: In this study, we demonstrated that the SVZ-derived aNSCs might be major targets of NPC. Significantly, aNSCs showed different responses depending on their anatomical origins due to dissimilarities in their cholesterol transporting system and NO-dependent JNK activation. These findings can contribute to the understanding of the region-specific nature of the two SVZ and DG neurogenic niches. Antioxid. Redox Signal. 00, 000-000.
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Affiliation(s)
- Yoojin Seo
- 1 Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University , Seoul, Republic of Korea
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45
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Mercer AJ, Szalewski RJ, Jackman SL, Van Hook MJ, Thoreson WB. Regulation of presynaptic strength by controlling Ca2+ channel mobility: effects of cholesterol depletion on release at the cone ribbon synapse. J Neurophysiol 2012; 107:3468-78. [PMID: 22442573 DOI: 10.1152/jn.00779.2011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Synaptic communication requires proper coupling between voltage-gated Ca(2+) (Ca(V)) channels and synaptic vesicles. In photoreceptors, L-type Ca(V) channels are clustered close to synaptic ribbon release sites. Although clustered, Ca(V) channels move continuously within a confined domain slightly larger than the base of the ribbon. We hypothesized that expanding Ca(V) channel confinement domains should increase the number of channel openings needed to trigger vesicle release. Using single-particle tracking techniques, we measured the expansion of Ca(V) channel confinement domains caused by depletion of membrane cholesterol with cholesterol oxidase or methyl-β-cyclodextrin. With paired whole cell recordings from cones and horizontal cells, we then determined the number of Ca(V) channel openings contributing to cone Ca(V) currents (I(Ca)) and the number of vesicle fusion events contributing to horizontal cell excitatory postsynaptic currents (EPSCs) following cholesterol depletion. Expansion of Ca(V) channel confinement domains reduced the peak efficiency of release, decreasing the number of vesicle fusion events accompanying opening of each Ca(V) channel. Cholesterol depletion also inhibited exocytotic capacitance increases evoked by brief depolarizing steps. Changes in efficiency were not due to changes in I(Ca) amplitude or glutamate receptor properties. Replenishing cholesterol restored Ca(V) channel domain size and release efficiency to control levels. These results indicate that cholesterol is important for organizing the cone active zone. Furthermore, the finding that cholesterol depletion impairs coupling between channel opening and vesicle release by allowing Ca(V) channels to move further from release sites shows that changes in presynaptic Ca(V) channel mobility can be a mechanism for adjusting synaptic strength.
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Affiliation(s)
- Aaron J Mercer
- Dept. of Ophthalmology and Visual Sciences, Univ. of Nebraska Medical Center, Omaha, NE 68198-5840, USA
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46
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Lakkaraju A. Endo-lysosome function in the retinal pigment epithelium in health and disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 723:723-9. [PMID: 22183399 DOI: 10.1007/978-1-4614-0631-0_92] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Aparna Lakkaraju
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, 1300 University Ave, MSC 3385, Madison, WI 53706, USA.
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47
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Invertebrate models of lysosomal storage disease: what have we learned so far? INVERTEBRATE NEUROSCIENCE 2011; 11:59-71. [PMID: 22038288 DOI: 10.1007/s10158-011-0125-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 10/08/2011] [Indexed: 01/17/2023]
Abstract
The lysosomal storage diseases (LSDs) collectively account for death in 1 in 8,000 children. Although some forms are treatable, they are essentially incurable and usually are lethal in the first decade of life. The most intractable forms of LSD are those with neuronal involvement. In an effort to identify the pathological signaling driving pathology in the LSDs, invertebrate models have been developed. In this review, we outline our current understanding of LSDs and recent findings using invertebrate models. We outline strategies and pitfalls for the development of such models. Available models of LSD in Drosophila and Caenorhabditis elegans are uncovering roles for LSD-related proteins with previously unknown function using both gain-of-function and loss-of-function strategies. These models of LSD in Drosophila and C. elegans have identified potential pathogenic signaling cascades that are proving critical to our understanding of these lethal diseases.
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48
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Yu T, Shakkottai VG, Chung C, Lieberman AP. Temporal and cell-specific deletion establishes that neuronal Npc1 deficiency is sufficient to mediate neurodegeneration. Hum Mol Genet 2011; 20:4440-51. [PMID: 21856732 DOI: 10.1093/hmg/ddr372] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Niemann-Pick type C (NPC) disease is an autosomal recessive lysosomal storage disorder caused by mutations in the NPC1 or NPC2 genes. Loss of function mutations in either gene disrupt intracellular lipid trafficking and lead to a clinically heterogeneous phenotype that invariably includes neurological dysfunction and early death. The mechanism by which impaired lipid transport leads to neurodegeneration is poorly understood. Here we used mice with a conditional null allele to establish the timing and cell type that underlie neurodegeneration due to Npc1 deficiency. We show that global deletion of Npc1 in adult mice leads to progressive weight loss, impaired motor function and early death in a time course similar to that resulting from germline deletion. These phenotypes are associated with the occurrence of characteristic neuropathology including patterned Purkinje cell loss, axonal spheroids and reactive gliosis, demonstrating that there is not a significant developmental component to NPC neurodegeneration. Furthermore, we show that these same changes occur when Npc1 is specifically deleted only in neurons, establishing that neuronal deficiency is sufficient to mediate central nervous system (CNS) disease. In contrast, astrocyte-specific deletion does not impact behavioral phenotypes, CNS histopathology or synaptic function. We conclude that defects arising in neurons, but not in astrocytes, are the determining factor in the development of NPC neuropathology.
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Affiliation(s)
- Ting Yu
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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49
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Gatto CL, Broadie K. Fragile X mental retardation protein is required for programmed cell death and clearance of developmentally-transient peptidergic neurons. Dev Biol 2011; 356:291-307. [PMID: 21596027 PMCID: PMC3143227 DOI: 10.1016/j.ydbio.2011.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Revised: 04/22/2011] [Accepted: 05/03/2011] [Indexed: 01/19/2023]
Abstract
Fragile X syndrome (FXS), caused by loss of fragile X mental retardation 1 (FMR1) gene function, is the most common heritable cause of intellectual disability and autism spectrum disorders. The FMR1 product (FMRP) is an RNA-binding protein best established to function in activity-dependent modulation of synaptic connections. In the Drosophila FXS disease model, loss of functionally-conserved dFMRP causes synaptic overgrowth and overelaboration in pigment dispersing factor (PDF) peptidergic neurons in the adult brain. Here, we identify a very different component of PDF neuron misregulation in dfmr1 mutants: the aberrant retention of normally developmentally-transient PDF tritocerebral (PDF-TRI) neurons. In wild-type animals, PDF-TRI neurons in the central brain undergo programmed cell death and complete, processive clearance within days of eclosion. In the absence of dFMRP, a defective apoptotic program leads to constitutive maintenance of these peptidergic neurons. We tested whether this apoptotic defect is circuit-specific by examining crustacean cardioactive peptide (CCAP) and bursicon circuits, which are similarly developmentally-transient and normally eliminated immediately post-eclosion. In dfmr1 null mutants, CCAP/bursicon neurons also exhibit significantly delayed clearance dynamics, but are subsequently eliminated from the nervous system, in contrast to the fully persistent PDF-TRI neurons. Thus, the requirement of dFMRP for the retention of transitory peptidergic neurons shows evident circuit specificity. The novel defect of impaired apoptosis and aberrant neuron persistence in the Drosophila FXS model suggests an entirely new level of "pruning" dysfunction may contribute to the FXS disease state.
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Affiliation(s)
- Cheryl L Gatto
- Departments of Biological Sciences and Cell and Developmental Biology, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37232, USA
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50
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Schwend T, Loucks EJ, Snyder D, Ahlgren SC. Requirement of Npc1 and availability of cholesterol for early embryonic cell movements in zebrafish. J Lipid Res 2011; 52:1328-44. [PMID: 21576600 DOI: 10.1194/jlr.m012377] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Niemann-Pick disease, type C (NP-C), often associated with Niemann-Pick disease, type C1 (NPC1) mutations, is a cholesterol-storage disorder characterized by cellular lipid accumulation, neurodegeneration, and reduced steroid production. To study NPC1 function in vivo, we cloned zebrafish npc1 and analyzed its gene expression and activity by reducing Npc1 protein with morpholino (MO)-oligonucleotides. Filipin staining in npc1-morphant cells was punctate, suggesting abnormal accumulation of cholesterol. Developmentally, reducing Npc1 did not disrupt early cell fate or survival; however, early morphogenetic movements were delayed, and the actin cytoskeleton network was abnormal. MO-induced defects were rescued with ectopic expression of mouse NPC1, demonstrating functional gene conservation, and by treatments with steroids pregnenolone or dexamethasone, suggesting that reduced steroidogenesis contributed to abnormal cell movements. Cell death was found in anterior tissues of npc1 morphants at later stages, consistent with findings in mammals. Collectively, these studies show that npc1 is required early for proper cell movement and cholesterol localization and later for cell survival.
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Affiliation(s)
- Tyler Schwend
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago , IL, USA
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