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Genotype-Phenotype Correlations in Human Diseases Caused by Mutations of LINC Complex-Associated Genes: A Systematic Review and Meta-Summary. Cells 2022; 11:cells11244065. [PMID: 36552829 PMCID: PMC9777268 DOI: 10.3390/cells11244065] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/09/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Mutations in genes encoding proteins associated with the linker of nucleoskeleton and cytoskeleton (LINC) complex within the nuclear envelope cause different diseases with varying phenotypes including skeletal muscle, cardiac, metabolic, or nervous system pathologies. There is some understanding of the structure of LINC complex-associated proteins and how they interact, but it is unclear how mutations in genes encoding them can cause the same disease, and different diseases with different phenotypes. Here, published mutations in LINC complex-associated proteins were systematically reviewed and analyzed to ascertain whether patterns exist between the genetic sequence variants and clinical phenotypes. This revealed LMNA is the only LINC complex-associated gene in which mutations commonly cause distinct conditions, and there are no clear genotype-phenotype correlations. Clusters of LMNA variants causing striated muscle disease are located in exons 1 and 6, and metabolic disease-associated LMNA variants are frequently found in the tail of lamin A/C. Additionally, exon 6 of the emerin gene, EMD, may be a mutation "hot-spot", and diseases related to SYNE1, encoding nesprin-1, are most often caused by nonsense type mutations. These results provide insight into the diverse roles of LINC-complex proteins in human disease and provide direction for future gene-targeted therapy development.
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Kwak DH, Park JH, Choi ES, Park SH, Lee SY, Lee S. Ganglioside GD1a enhances osteogenesis by activating ERK1/2 in mesenchymal stem cells of Lmna mutant mice. Aging (Albany NY) 2022; 14:9445-9457. [PMID: 36375476 PMCID: PMC9792213 DOI: 10.18632/aging.204378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 10/24/2022] [Indexed: 11/16/2022]
Abstract
Mutations in Lmna usually cause a series of human disorders, such as premature aging syndrome (progeria) involving the skeletal system. Gangliosides are known to be involved in cell surface differentiation and proliferation of stem cells. However, the role of gangliosides in Lmna dysfunctional mesenchymal stem cells (MSCs) is unclear. Therefore, Ganglioside's role in osteogenesis of Lmna dysfunctional MSCs analyzed. As a result of the analysis, it was confirmed that the expression of ganglioside GD1a was significantly reduced in MSCs derived from LmnaDhe/+ mice and in MSCs subjected to Lamin A/C knockdown using siRNA. Osteogenesis-related bone morphogenetic protein-2 and Osteocalcin protein, and gene expression were significantly decreased due to Lmna dysfunction. A result of treating MSCs with Lmna dysfunction with ganglioside GD1a (3 μg/ml), significantly increased bone differentiation in ganglioside GD1a treatment to Lmna-mutated MSCs. In addition, the level of pERK1/2, related to bone differentiation mechanisms was significantly increased. Ganglioside GD1a was treated to Congenital progeria LmnaDhe/+ mice. As a result, femur bone volume in ganglioside GD1a-treated LmnaDhe/+ mice was more significantly increased than in the LmnaDhe/+ mice. Therefore, it was confirmed that the ganglioside GD1a plays an important role in enhancing osteogenic differentiation in MSC was a dysfunction of Lmna.
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Affiliation(s)
- Dong Hoon Kwak
- Department of Pharmacology, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
- Brain Research Institute, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
| | - Ji Hye Park
- Department of Pharmacology, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
- Brain Research Institute, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
| | - Eul Sig Choi
- Department of Pharmacology, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
- Brain Research Institute, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
| | - Seong Hyun Park
- Department of Pharmacology, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
- Brain Research Institute, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
| | - Seo-Yeon Lee
- Department of Pharmacology, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
- Brain Research Institute, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
| | - Seoul Lee
- Department of Pharmacology, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
- Brain Research Institute, Wonkwang University, Iksan, Jeollabuk-do 54538, Republic of Korea
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3
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Lessel I, Chen MJ, Lüttgen S, Arndt F, Fuchs S, Meien S, Thiele H, Jones JR, Shaw BR, Crossman DK, Nürnberg P, Korf BR, Kubisch C, Lessel D. Two novel cases further expand the phenotype of TOR1AIP1-associated nuclear envelopathies. Hum Genet 2020; 139:483-498. [PMID: 32055997 PMCID: PMC7078146 DOI: 10.1007/s00439-019-02105-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 12/22/2019] [Indexed: 12/19/2022]
Abstract
Biallelic variants in TOR1AIP1, encoding the integral nuclear membrane protein LAP1 (lamina-associated polypeptide 1) with two functional isoforms LAP1B and LAP1C, have initially been linked to muscular dystrophies with variable cardiac and neurological impairment. Furthermore, a recurrent homozygous nonsense alteration, resulting in loss of both LAP1 isoforms, was identified in seven likely related individuals affected by multisystem anomalies with progeroid-like appearance and lethality within the 1st decade of life. Here, we have identified compound heterozygosity in TOR1AIP1 affecting both LAP1 isoforms in two unrelated individuals affected by congenital bilateral hearing loss, ventricular septal defect, bilateral cataracts, mild to moderate developmental delay, microcephaly, mandibular hypoplasia, short stature, progressive muscular atrophy, joint contractures and severe chronic heart failure, with much longer survival. Cellular characterization of primary fibroblasts of one affected individual revealed absence of both LAP1B and LAP1C, constitutively low lamin A/C levels, aberrant nuclear morphology including nuclear cytoplasmic channels, and premature senescence, comparable to findings in other progeroid forms of nuclear envelopathies. We additionally observed an abnormal activation of the extracellular signal-regulated kinase 1/2 (ERK 1/2). Ectopic expression of wild-type TOR1AIP1 mitigated these cellular phenotypes, providing further evidence for the causal role of identified genetic variants. Altogether, we thus further expand the TOR1AIP1-associated phenotype by identifying individuals with biallelic loss-of-function variants who survived beyond the 1st decade of life and reveal novel molecular consequences underlying the TOR1AIP1-associated disorders.
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Affiliation(s)
- Ivana Lessel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Mei-Jan Chen
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, 36394, USA
| | - Sabine Lüttgen
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Florian Arndt
- Department for Pediatric Cardiology, University Heart Center Hamburg, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Sigrid Fuchs
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Stefanie Meien
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Holger Thiele
- Cologne Center for Genomics, University of Cologne, 50931, Cologne, Germany
| | - Julie R Jones
- Molecular Diagnostic Laboratory, Greenwood Genetic Center, Greenwood, SC, 29646, USA
| | - Brandon R Shaw
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, 36394, USA
| | - David K Crossman
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, 36394, USA
| | - Peter Nürnberg
- Cologne Center for Genomics, University of Cologne, 50931, Cologne, Germany.,Center for Molecular Medicine Cologne, University of Cologne, 50931, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, 50931, Cologne, Germany
| | - Bruce R Korf
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, 36394, USA
| | - Christian Kubisch
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Davor Lessel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
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Dubińska-Magiera M, Kozioł K, Machowska M, Piekarowicz K, Filipczak D, Rzepecki R. Emerin Is Required for Proper Nucleus Reassembly after Mitosis: Implications for New Pathogenetic Mechanisms for Laminopathies Detected in EDMD1 Patients. Cells 2019; 8:E240. [PMID: 30871242 PMCID: PMC6468536 DOI: 10.3390/cells8030240] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 02/26/2019] [Accepted: 03/05/2019] [Indexed: 12/29/2022] Open
Abstract
Emerin is an essential LEM (LAP2, Emerin, MAN1) domain protein in metazoans and an integral membrane protein associated with inner and outer nuclear membranes. Mutations in the human EMD gene coding for emerin result in the rare genetic disorder: Emery⁻Dreifuss muscular dystrophy type 1 (EDMD1). This disease belongs to a broader group called laminopathies-a heterogeneous group of rare genetic disorders affecting tissues of mesodermal origin. EDMD1 phenotype is characterized by progressive muscle wasting, contractures of the elbow and Achilles tendons, and cardiac conduction defects. Emerin is involved in many cellular and intranuclear processes through interactions with several partners: lamins; barrier-to-autointegration factor (BAF), β-catenin, actin, and tubulin. Our study demonstrates the presence of the emerin fraction which associates with mitotic spindle microtubules and centrosomes during mitosis and colocalizes during early mitosis with lamin A/C, BAF, and membranes at the mitotic spindle. Transfection studies with cells expressing EGFP-emerin protein demonstrate that the emerin fusion protein fraction also localizes to centrosomes and mitotic spindle microtubules during mitosis. Transient expression of emerin deletion mutants revealed that the resulting phenotypes vary and are mutant dependent. The most frequent phenotypes include aberrant nuclear shape, tubulin network mislocalization, aberrant mitosis, and mislocalization of centrosomes. Emerin deletion mutants demonstrated different chromatin binding capacities in an in vitro nuclear assembly assay and chromatin-binding properties correlated with the strength of phenotypic alteration in transfected cells. Aberrant tubulin staining and microtubule network phenotype appearance depended on the presence of the tubulin binding region in the expressed deletion mutants. We believe that the association with tubulin might help to "deliver" emerin and associated membranes to decondensing chromatin. Preliminary analyses of cells from Polish patients with EDMD1 revealed that for several mutations thought to be null for emerin protein, a truncated emerin protein was present. We infer that the EDMD1 phenotype may be strengthened by the toxicity of truncated emerin expressed in patients with certain nonsense mutations in EMD.
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Affiliation(s)
- Magda Dubińska-Magiera
- Laboratory of Nuclear Proteins, Faculty of Biotechnology, University of Wroclaw, Fryderyka Joliot-Curie 14a, 50-383 Wroclaw, Poland.
- Department of Animal Developmental Biology, Institute of Experimental Biology, University of Wroclaw, Sienkiewicza 21, 50-335 Wroclaw, Poland.
| | - Katarzyna Kozioł
- Laboratory of Nuclear Proteins, Faculty of Biotechnology, University of Wroclaw, Fryderyka Joliot-Curie 14a, 50-383 Wroclaw, Poland.
| | - Magdalena Machowska
- Laboratory of Nuclear Proteins, Faculty of Biotechnology, University of Wroclaw, Fryderyka Joliot-Curie 14a, 50-383 Wroclaw, Poland.
| | - Katarzyna Piekarowicz
- Laboratory of Nuclear Proteins, Faculty of Biotechnology, University of Wroclaw, Fryderyka Joliot-Curie 14a, 50-383 Wroclaw, Poland.
| | - Daria Filipczak
- Laboratory of Nuclear Proteins, Faculty of Biotechnology, University of Wroclaw, Fryderyka Joliot-Curie 14a, 50-383 Wroclaw, Poland.
| | - Ryszard Rzepecki
- Laboratory of Nuclear Proteins, Faculty of Biotechnology, University of Wroclaw, Fryderyka Joliot-Curie 14a, 50-383 Wroclaw, Poland.
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5
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Mohammad RM, Muqbil I, Lowe L, Yedjou C, Hsu HY, Lin LT, Siegelin MD, Fimognari C, Kumar NB, Dou QP, Yang H, Samadi AK, Russo GL, Spagnuolo C, Ray SK, Chakrabarti M, Morre JD, Coley HM, Honoki K, Fujii H, Georgakilas AG, Amedei A, Niccolai E, Amin A, Ashraf SS, Helferich WG, Yang X, Boosani CS, Guha G, Bhakta D, Ciriolo MR, Aquilano K, Chen S, Mohammed SI, Keith WN, Bilsland A, Halicka D, Nowsheen S, Azmi AS. Broad targeting of resistance to apoptosis in cancer. Semin Cancer Biol 2015; 35 Suppl:S78-S103. [PMID: 25936818 PMCID: PMC4720504 DOI: 10.1016/j.semcancer.2015.03.001] [Citation(s) in RCA: 517] [Impact Index Per Article: 57.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 03/04/2015] [Accepted: 03/04/2015] [Indexed: 12/15/2022]
Abstract
Apoptosis or programmed cell death is natural way of removing aged cells from the body. Most of the anti-cancer therapies trigger apoptosis induction and related cell death networks to eliminate malignant cells. However, in cancer, de-regulated apoptotic signaling, particularly the activation of an anti-apoptotic systems, allows cancer cells to escape this program leading to uncontrolled proliferation resulting in tumor survival, therapeutic resistance and recurrence of cancer. This resistance is a complicated phenomenon that emanates from the interactions of various molecules and signaling pathways. In this comprehensive review we discuss the various factors contributing to apoptosis resistance in cancers. The key resistance targets that are discussed include (1) Bcl-2 and Mcl-1 proteins; (2) autophagy processes; (3) necrosis and necroptosis; (4) heat shock protein signaling; (5) the proteasome pathway; (6) epigenetic mechanisms; and (7) aberrant nuclear export signaling. The shortcomings of current therapeutic modalities are highlighted and a broad spectrum strategy using approaches including (a) gossypol; (b) epigallocatechin-3-gallate; (c) UMI-77 (d) triptolide and (e) selinexor that can be used to overcome cell death resistance is presented. This review provides a roadmap for the design of successful anti-cancer strategies that overcome resistance to apoptosis for better therapeutic outcome in patients with cancer.
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Affiliation(s)
- Ramzi M Mohammad
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States; Interim translational Research Institute, Hamad Medical Corporation, Doha, Qatar.
| | - Irfana Muqbil
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
| | - Leroy Lowe
- Getting to Know Cancer, Truro, Nova Scotia, Canada
| | - Clement Yedjou
- C-SET, [Jackson, #229] State University, Jackson, MS, United States
| | - Hsue-Yin Hsu
- Department of Life Sciences, Tzu-Chi University, Hualien, Taiwan
| | - Liang-Tzung Lin
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Markus David Siegelin
- Department of Pathology and Cell Biology, Columbia University, New York City, NY, United States
| | - Carmela Fimognari
- Dipartimento di Scienze per la Qualità della Vita Alma Mater Studiorum-Università di Bologna, Italy
| | - Nagi B Kumar
- Moffit Cancer Center, University of South Florida College of Medicine, Tampa, FL, United States
| | - Q Ping Dou
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States; Departments of Pharmacology and Pathology, Karmanos Cancer Institute, Detroit MI, United States
| | - Huanjie Yang
- The School of Life Science and Technology, Harbin Institute of Technology, Harbin, Heilongjiang, China
| | | | - Gian Luigi Russo
- Institute of Food Sciences National Research Council, Avellino, Italy
| | - Carmela Spagnuolo
- Institute of Food Sciences National Research Council, Avellino, Italy
| | - Swapan K Ray
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC, United States
| | - Mrinmay Chakrabarti
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC, United States
| | - James D Morre
- Mor-NuCo, Inc, Purdue Research Park, West Lafayette, IN, United States
| | - Helen M Coley
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - Kanya Honoki
- Department of Orthopedic Surgery, Nara Medical University, Kashihara, Japan
| | - Hiromasa Fujii
- Department of Orthopedic Surgery, Nara Medical University, Kashihara, Japan
| | - Alexandros G Georgakilas
- Department of Physics, School of Applied Mathematical and Physical Sciences, National Technical University of Athens, Zografou 15780, Athens, Greece
| | - Amedeo Amedei
- Department of Experimental and Clinical Medicine, university of florence, Italy
| | - Elena Niccolai
- Department of Experimental and Clinical Medicine, university of florence, Italy
| | - Amr Amin
- Department of Biology, College of Science, UAE University, United Arab Emirates; Faculty of Science, Cairo University, Egypt
| | - S Salman Ashraf
- Department of Chemistry, College of Science, UAE University, United Arab Emirates
| | - William G Helferich
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Xujuan Yang
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Chandra S Boosani
- Department of BioMedical Sciences, School of Medicine Creighton University, Omaha NE, United States
| | - Gunjan Guha
- School of Chemical and Bio Technology, SASTRA University, Thanjavur, India
| | - Dipita Bhakta
- School of Chemical and Bio Technology, SASTRA University, Thanjavur, India
| | | | - Katia Aquilano
- Department of Biology, University of Rome "Tor Vergata", Italy
| | - Sophie Chen
- Ovarian and Prostate Cancer Research Trust Laboratory, Guildford, Surrey, United Kingdom
| | - Sulma I Mohammed
- Department of Comparative Pathobiology and Purdue University Center for Cancer Research, Purdue, West Lafayette, IN, United States
| | - W Nicol Keith
- Institute of Cancer Sciences, University of Glasgow, Glasgow, Ireland
| | - Alan Bilsland
- Institute of Cancer Sciences, University of Glasgow, Glasgow, Ireland
| | - Dorota Halicka
- Department of Pathology, New York Medical College, Valhalla, NY, United States
| | - Somaira Nowsheen
- Mayo Graduate School, Mayo Medical School, Mayo Clinic Medical Scientist Training Program, Rochester, MN, United States
| | - Asfar S Azmi
- Department of Oncology, Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
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Wong X, Luperchio TR, Reddy KL. NET gains and losses: the role of changing nuclear envelope proteomes in genome regulation. Curr Opin Cell Biol 2014; 28:105-20. [PMID: 24886773 DOI: 10.1016/j.ceb.2014.04.005] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 03/21/2014] [Accepted: 04/11/2014] [Indexed: 01/13/2023]
Abstract
In recent years, our view of the nucleus has changed considerably with an increased awareness of the roles dynamic higher order chromatin structure and nuclear organization play in nuclear function. More recently, proteomics approaches have identified differential expression of nuclear lamina and nuclear envelope transmembrane (NET) proteins. Many NETs have been implicated in a range of developmental disorders as well as cell-type specific biological processes, including genome organization and nuclear morphology. While further studies are needed, it is clear that the differential nuclear envelope proteome contributes to cell-type specific nuclear identity and functions. This review discusses the importance of proteome diversity at the nuclear periphery and highlights the putative roles of NET proteins, with a focus on nuclear architecture.
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Affiliation(s)
- Xianrong Wong
- Johns Hopkins University, School of Medicine, Department of Biological Chemistry and Center for Epigenetics, 855N. Wolfe St., Rangos 574, Baltimore, MD 21044, United States
| | - Teresa R Luperchio
- Johns Hopkins University, School of Medicine, Department of Biological Chemistry and Center for Epigenetics, 855N. Wolfe St., Rangos 574, Baltimore, MD 21044, United States
| | - Karen L Reddy
- Johns Hopkins University, School of Medicine, Department of Biological Chemistry and Center for Epigenetics, 855N. Wolfe St., Rangos 574, Baltimore, MD 21044, United States.
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7
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Oleas J, Yokoi F, DeAndrade MP, Pisani A, Li Y. Engineering animal models of dystonia. Mov Disord 2014; 28:990-1000. [PMID: 23893455 DOI: 10.1002/mds.25583] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 05/25/2013] [Accepted: 05/29/2013] [Indexed: 12/19/2022] Open
Abstract
Dystonia is a neurological disorder characterized by abnormal involuntary movements that are prolonged and often cause twisting and turning. Several genetically modified worms, fruit flies, and rodents have been generated as models of genetic dystonias, in particular DYT1, DYT11, and DYT12 dystonias. Although these models do not show overt dystonic symptoms, the rodent models exhibit motor deficits in specialized behavioral tasks, such as the rotarod and beam-walking tests. For example, in a rodent model of DYT12 dystonia, which is generally stress triggered, motor deficits are observed only after the animal is stressed. Moreover, in a rodent model of DYT1 dystonia, the motor and electrophysiological deficits can be rescued by trihexyphenidyl, a common anticholinergic medication used to treat dystonic symptoms in human patients. Biochemically, the DYT1 and DYT11 animal models also share some similarities to patients, such as a reduction in striatal D2 dopamine receptor and binding activities. In addition, conditional knockout mouse models for DYT1 and DYT11 dystonia demonstrate that loss of the causal dystonia-related proteins in the striatum leads to motor deficits. Interestingly, loss of the DYT1 dystonia causal protein in Purkinje cells shows an improvement in motor performance, suggesting that gene therapy targeting of the cerebellum or intervention in its downstream pathways may be useful. Finally, recent studies using DYT1 dystonia worm and mouse models led to a potential novel therapeutic agent, which is currently undergoing clinical trials. These results indicate that genetic animal models are powerful tools to elucidate the pathophysiology and to further develop new therapeutics for dystonia.
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Affiliation(s)
- Janneth Oleas
- Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida 32610, USA
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8
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Genome regulation at the peripheral zone: lamina associated domains in development and disease. Curr Opin Genet Dev 2014; 25:50-61. [PMID: 24556270 DOI: 10.1016/j.gde.2013.11.021] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 11/29/2013] [Indexed: 12/18/2022]
Abstract
The nuclear periphery has been implicated in gene regulation and it has been proposed that proximity to the nuclear lamina and inner nuclear membrane (INM) leads to gene repression. More recently, it appears that there is a correlation and interdependence between lamina associated domains (LADs), the epigenome and overall three-dimensional architecture of the genome. However, the mechanisms of such organization at the 'peripheral zone' and the functional significance of these associations are poorly understood. The role these domains play in development and disease is an active and exciting area of research, expanding our knowledge of how the three-dimensional (3D) genome is regulated.
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9
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Osorio DS, Gomes ER. The contemporary nucleus: A trip down memory lane. Biol Cell 2013; 105:430-41. [DOI: 10.1111/boc.201300009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 06/21/2013] [Indexed: 01/12/2023]
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10
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Chen CY, Chi YH, Mutalif RA, Starost MF, Myers TG, Anderson SA, Stewart CL, Jeang KT. Accumulation of the inner nuclear envelope protein Sun1 is pathogenic in progeric and dystrophic laminopathies. Cell 2012; 149:565-77. [PMID: 22541428 PMCID: PMC3340584 DOI: 10.1016/j.cell.2012.01.059] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 12/01/2011] [Accepted: 01/30/2012] [Indexed: 11/28/2022]
Abstract
Human LMNA gene mutations result in laminopathies that include Emery-Dreifuss muscular dystrophy (AD-EDMD) and Hutchinson-Gilford progeria, the premature aging syndrome (HGPS). The Lmna null (Lmna(-/-)) and progeroid LmnaΔ9 mutant mice are models for AD-EDMD and HGPS, respectively. Both animals develop severe tissue pathologies with abbreviated life spans. Like HGPS cells, Lmna(-/-) and LmnaΔ9 fibroblasts have typically misshapen nuclei. Unexpectedly, Lmna(-/-) or LmnaΔ9 mice that are also deficient for the inner nuclear membrane protein Sun1 show markedly reduced tissue pathologies and enhanced longevity. Concordantly, reduction of SUN1 overaccumulation in LMNA mutant fibroblasts and in cells derived from HGPS patients corrected nuclear defects and cellular senescence. Collectively, these findings implicate Sun1 protein accumulation as a common pathogenic event in Lmna(-/-), LmnaΔ9, and HGPS disorders.
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Affiliation(s)
- Chia-Yen Chen
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ya-Hui Chi
- the National Health Research Institutes, Zhunan, Taiwan
| | | | - Matthew F. Starost
- Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
| | - Timothy G. Myers
- Microarray Research Facility, Genomic Technologies Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Stasia A. Anderson
- National Heart, Lung, and Blood Institute Animal MRI Core, National Institutes of Health, Bethesda, MD, USA
| | | | - Kuan-Teh Jeang
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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11
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Yokoi F, Dang MT, Yang G, Li J, Doroodchi A, Zhou T, Li Y. Abnormal nuclear envelope in the cerebellar Purkinje cells and impaired motor learning in DYT11 myoclonus-dystonia mouse models. Behav Brain Res 2012; 227:12-20. [PMID: 22040906 PMCID: PMC3242862 DOI: 10.1016/j.bbr.2011.10.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 10/10/2011] [Accepted: 10/16/2011] [Indexed: 11/22/2022]
Abstract
Myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonia. DYT11 M-D is caused by mutations in SGCE which codes for ɛ-sarcoglycan. SGCE is maternally imprinted and paternally expressed. Abnormal nuclear envelope has been reported in mouse models of DYT1 generalized torsion dystonia. However, it is not known whether similar alterations occur in DYT11 M-D. We developed a mouse model of DYT11 M-D using paternally inherited Sgce heterozygous knockout (Sgce KO) mice and reported that they had myoclonus and motor coordination and learning deficits in the beam-walking test. However, the specific brain regions that contribute to these phenotypes have not been identified. Since ɛ-sarcoglycan is highly expressed in the cerebellar Purkinje cells, here we examined the nuclear envelope in these cells using a transmission electron microscope and found that they are abnormal in Sgce KO mice. Our results put DYT11 M-D in a growing family of nuclear envelopathies. To analyze the effect of loss of ɛ-sarcoglycan function in the cerebellar Purkinje cells, we produced paternally inherited cerebellar Purkinje cell-specific Sgce conditional knockout (Sgce pKO) mice. Sgce pKO mice showed motor learning deficits, while they did not show abnormal nuclear envelope in the cerebellar Purkinje cells, robust motor deficits, or myoclonus. The results suggest that ɛ-sarcoglycan in the cerebellar Purkinje cells contributes to the motor learning, while loss of ɛ-sarcoglycan in other brain regions may contribute to nuclear envelope abnormality, myoclonus and motor coordination deficits.
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Affiliation(s)
- Fumiaki Yokoi
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Mai T. Dang
- Department of Neurology, Hospital of University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Guang Yang
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - JinDong Li
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Atbin Doroodchi
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Tong Zhou
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yuqing Li
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
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Yokoi F, Dang MT, Zhou T, Li Y. Abnormal nuclear envelopes in the striatum and motor deficits in DYT11 myoclonus-dystonia mouse models. Hum Mol Genet 2011; 21:916-25. [PMID: 22080833 DOI: 10.1093/hmg/ddr528] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
DYT11 myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonic symptoms and caused by mutations in paternally expressed SGCE, which codes for ε-sarcoglycan. Paternally inherited Sgce heterozygous knock-out (KO) mice exhibit motor deficits and spontaneous myoclonus. Abnormal nuclear envelopes have been reported in cellular and mouse models of early-onset DYT1 generalized torsion dystonia; however, the relationship between the abnormal nuclear envelopes and motor symptoms are not clear. Furthermore, it is not known whether abnormal nuclear envelope exists in non-DYT1 dystonia. In the present study, abnormal nuclear envelopes in the striatal medium spiny neurons (MSNs) were found in Sgce KO mice. To analyze whether the loss of ε-sarcoglycan in the striatum alone causes abnormal nuclear envelopes, motor deficits or myoclonus, we produced paternally inherited striatum-specific Sgce conditional KO (Sgce sKO) mice and analyzed their phenotypes. Sgce sKO mice exhibited motor deficits in both beam-walking and accelerated rotarod tests, while they did not exhibit abnormal nuclear envelopes, alteration in locomotion, or myoclonus. The results suggest that the loss of ε-sarcoglycan in the striatum contributes to motor deficits, while it alone does not produce abnormal nuclear envelopes or myoclonus. Development of therapies targeting the striatum to compensate for the loss of ε-sarcoglycan function may rescue the motor deficits in DYT11 M-D patients.
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Affiliation(s)
- Fumiaki Yokoi
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610-0236, USA
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13
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Odgren PR, Pratt CH, MacKay CA, Mason-Savas A, Curtain M, Shopland L, Ichicki T, Sundberg JP, Donahue LR. Disheveled hair and ear (Dhe), a spontaneous mouse Lmna mutation modeling human laminopathies. PLoS One 2010; 5:e9959. [PMID: 20376364 PMCID: PMC2848607 DOI: 10.1371/journal.pone.0009959] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Accepted: 03/11/2010] [Indexed: 12/23/2022] Open
Abstract
Background Investigations of naturally-occurring mutations in animal models provide important insights and valuable disease models. Lamins A and C, along with lamin B, are type V intermediate filament proteins which constitute the proteinaceous boundary of the nucleus. LMNA mutations in humans cause a wide range of phenotypes, collectively termed laminopathies. To identify the mutation and investigate the phenotype of a spontaneous, semi-dominant mutation that we have named Disheveled hair and ear (Dhe), which causes a sparse coat and small external ears in heterozygotes and lethality in homozygotes by postnatal day 10. Findings Genetic mapping identified a point mutation in the Lmna gene, causing a single amino acid change, L52R, in the coiled coil rod domain of lamin A and C proteins. Cranial sutures in Dhe/+ mice failed to close. Gene expression for collagen types I and III in sutures was deficient. Skulls were small and disproportionate. Skeletons of Dhe/+ mice were hypomineralized and total body fat was deficient in males. In homozygotes, skin and oral mucosae were dysplastic and ulcerated. Nuclear morphometry of cultured cells revealed gene dose-dependent blebbing and wrinkling. Conclusion Dhe mice should provide a useful new model for investigations of the pathogenesis of laminopathies.
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Affiliation(s)
- Paul R. Odgren
- Department of Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Craig H. Pratt
- Institute for Molecular Biophysics, Bar Harbor, Maine, United States of America
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Carole A. MacKay
- Department of Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - April Mason-Savas
- Department of Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Michelle Curtain
- Genetic Resource Science, Bar Harbor, Maine, United States of America
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Lindsay Shopland
- Institute for Molecular Biophysics, Bar Harbor, Maine, United States of America
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Tsutomu Ichicki
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - John P. Sundberg
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Leah Rae Donahue
- Genetic Resource Science, Bar Harbor, Maine, United States of America
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- * E-mail:
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Chi YH, Chen ZJ, Jeang KT. The nuclear envelopathies and human diseases. J Biomed Sci 2009; 16:96. [PMID: 19849840 PMCID: PMC2770040 DOI: 10.1186/1423-0127-16-96] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Accepted: 10/22/2009] [Indexed: 12/30/2022] Open
Abstract
The nuclear envelope (NE) consists of two membrane layers that segregate the nuclear from the cytoplasmic contents. Recent progress in our understanding of nuclear-lamina associated diseases has revealed intriguing connections between the envelope components and nuclear processes. Here, we review the functions of the nuclear envelope in chromosome organization, gene expression, DNA repair and cell cycle progression, and correlate deficiencies in envelope function with human pathologies.
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Affiliation(s)
- Ya-Hui Chi
- Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan 35053, Taiwan, Republic of China
| | - Zi-Jie Chen
- Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan 35053, Taiwan, Republic of China
| | - Kuan-Teh Jeang
- Molecular Virology Section, Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
- Building 4, Room 306, 9000 Rockville Pike, Bethesda, MD 20892-0460, USA
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15
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Abstract
During mitosis in metazoans, the nuclear envelope (NE) breaks down at prophase and reassembles at telophase. The regulation of NE assembly is essential to correct cell functioning. The complex issue of the regulation of NE formation remains to be solved. It is still uncertain that a single mechanism depicts NE formation during mitosis. The aim of this review is to address some of the cytological, biophysical, and molecular aspects of models of NE formation. Our emphasis is on the role of lipids and their modifying enzymes in envelope assembly. We consider how the NE can be used as a model in characterizing membrane dynamics during membrane fusion. Fusion mechanisms that give insight into the formation of the double membrane of the envelope are summarized. We speculate on the possible roles of phosphoinositides in membrane fusion and NE formation.
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Affiliation(s)
- Banafshé Larijani
- Lincoln's Inn Fields Laboratories, Cancer Research UK, London WC2A 3PX, UK.
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Haraguchi T, Kojidani T, Koujin T, Shimi T, Osakada H, Mori C, Yamamoto A, Hiraoka Y. Live cell imaging and electron microscopy reveal dynamic processes of BAF-directed nuclear envelope assembly. J Cell Sci 2008; 121:2540-54. [PMID: 18628300 DOI: 10.1242/jcs.033597] [Citation(s) in RCA: 165] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Assembly of the nuclear envelope (NE) in telophase is essential for higher eukaryotic cells to re-establish a functional nucleus. Time-lapse, FRAP and FRET analyses in human cells showed that barrier-to-autointegration factor (BAF), a DNA-binding protein, assembled first at the distinct ;core' region of the telophase chromosome and formed an immobile complex by directly binding with other core-localizing NE proteins, such as lamin A and emerin. Correlative light and electron microscopy after live cell imaging, further showed that BAF formed an electron-dense structure on the chromosome surface of the core, close to spindle microtubules (MTs) prior to the attachment of precursor NE membranes, suggesting that MTs may mediate core assembly of BAF. Disruption of the spindle MTs consistently abolished BAF accumulation at the core. In addition, RNAi of BAF eliminated the core assembly of lamin A and emerin, caused abnormal cytoplasmic accumulation of precursor nuclear membranes and resulted in a significant delay of NE assembly. These results suggest that the MT-mediated BAF accumulation at the core facilitates NE assembly at the end of mitosis.
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Affiliation(s)
- Tokuko Haraguchi
- CREST Research Project, Kobe Advanced ICT Research Center, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe, Japan.
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17
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Anderson DJ, Hetzer MW. Shaping the endoplasmic reticulum into the nuclear envelope. J Cell Sci 2008; 121:137-42. [PMID: 18187447 DOI: 10.1242/jcs.005777] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The nuclear envelope (NE), a double membrane enclosing the nucleus of eukaryotic cells, controls the flow of information between the nucleoplasm and the cytoplasm and provides a scaffold for the organization of chromatin and the cytoskeleton. In dividing metazoan cells, the NE breaks down at the onset of mitosis and then reforms around segregated chromosomes to generate the daughter nuclei. Recent data from intact cells and cell-free nuclear assembly systems suggest that the endoplasmic reticulum (ER) is the source of membrane for NE assembly. At the end of mitosis, ER membrane tubules are targeted to chromatin via tubule ends and reorganized into flat nuclear membrane sheets by specific DNA-binding membrane proteins. In contrast to previous models, which proposed vesicle fusion to be the principal mechanism of NE formation, these new studies suggest that the nuclear membrane forms by the chromatin-mediated reshaping of the ER.
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Affiliation(s)
- Daniel J Anderson
- Salk Institute for Biological Studies, Molecular and Cell Biology Laboratory, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
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18
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Truant R, Atwal RS, Burtnik A. Nucleocytoplasmic trafficking and transcription effects of huntingtin in Huntington's disease. Prog Neurobiol 2007; 83:211-27. [PMID: 17240517 DOI: 10.1016/j.pneurobio.2006.11.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 11/29/2006] [Accepted: 11/30/2006] [Indexed: 01/08/2023]
Abstract
There are nine genetic neurodegenerative diseases caused by a similar genetic defect, a CAG DNA triplet-repeat expansion in the disease gene's open reading frame resulting in a polyglutamine expansion in the disease proteins. Despite the commonality of polyglutamine expansion, each of the polyglutamine diseases manifest as unique diseases, with some similarities, but important differences. These differences suggest that the context of the polyglutamine expansion is important to the mechanism of pathology of the disease proteins. Therefore, it is becoming increasingly paramount to understand the normal functions of these polyglutamine disease proteins, which include huntingtin, the polyglutamine-expanded protein in Huntington's disease (HD). Transcriptional dysregulation is seen in HD. Here we discuss the role of normal huntingtin in transcriptional regulation and misregulation in Huntington's disease in relation to potentially analogous model systems, and to other polyglutamine disease proteins. Huntingtin has functional roles in both the cytoplasm and the nucleus. One commonality of activity of polyglutamine disease proteins is at the level of protein dynamics and ability to import and export to and from the nucleus. Knowing the temporal location of huntingtin protein in response to signaling and neuronal communication could lead to valuable insights into an important trigger of HD pathology.
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Affiliation(s)
- Ray Truant
- McMaster University, Department of Biochemistry and Biomedical Sciences, HSC4H24A, 1200 Main Street West, Hamilton, Ontario, Canada L8N3Z5.
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19
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20
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Broers JLV, Ramaekers FCS, Bonne G, Yaou RB, Hutchison CJ. Nuclear Lamins: Laminopathies and Their Role in Premature Ageing. Physiol Rev 2006; 86:967-1008. [PMID: 16816143 DOI: 10.1152/physrev.00047.2005] [Citation(s) in RCA: 441] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
It has been demonstrated that nuclear lamins are important proteins in maintaining cellular as well as nuclear integrity, and in maintaining chromatin organization in the nucleus. Moreover, there is growing evidence that lamins play a prominent role in transcriptional control. The family of laminopathies is a fast-growing group of diseases caused by abnormalities in the structure or processing of the lamin A/C ( LMNA) gene. Mutations or incorrect processing cause more than a dozen different inherited diseases, ranging from striated muscular diseases, via fat- and peripheral nerve cell diseases, to progeria. This broad spectrum of diseases can only be explained if the responsible A-type lamin proteins perform multiple functions in normal cells. This review gives an overview of current knowledge on lamin structure and function and all known diseases associated with LMNA abnormalities. Based on the knowledge of the different functions of A-type lamins and associated proteins, explanations for the observed phenotypes are postulated. It is concluded that lamins seem to be key players in, among others, controlling the process of cellular ageing, since disturbance in lamin protein structure gives rise to several forms of premature ageing.
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Affiliation(s)
- J L V Broers
- Department of Molecular Cell Biology, University of Maastricht, Research Institutes CARIM, GROW, and EURON, The Netherlands
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21
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Abstract
The muscular dystrophies are characterised by progressive muscle weakness and wasting. Pathologically the hallmarks are muscle fibre degeneration and fibrosis. Several recessive forms of muscular dystrophy are caused by defects in proteins localised to the sarcolemma. However, it is now apparent that others are due to defects in a wide range of proteins including those which are either nuclear-related (Emery-Dreifuss type muscular dystrophies, oculopharyngeal muscular dystrophy), enzymatic (limb-girdle muscular dystrophy 2A, myotonic dystrophy) or sarcomeric (limb-girdle muscular dystrophies 1A and 2G). Although the clinical and molecular basis of these disorders is heterogeneous all display myopathic morphological features. These include variation in fibre size, an increase in internal nuclei, and some myofibrillar distortion. Degeneration and fibrosis occur, but usually not to the same extent as in muscular dystrophies associated with sarcolemmal protein defects. This review outlines the genetic basis of these "non-sarcolemmal" forms of dystrophy and discusses current ideas on their pathogenesis.
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Affiliation(s)
- S C Brown
- Dubowitz Neuromuscular Centre, Imperial College School of Medicine, Hammersmith Hospital, London, UK
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22
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Lane KT, Beese LS. Thematic review series: lipid posttranslational modifications. Structural biology of protein farnesyltransferase and geranylgeranyltransferase type I. J Lipid Res 2006; 47:681-99. [PMID: 16477080 DOI: 10.1194/jlr.r600002-jlr200] [Citation(s) in RCA: 183] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
More than 100 proteins necessary for eukaryotic cell growth, differentiation, and morphology require posttranslational modification by the covalent attachment of an isoprenoid lipid (prenylation). Prenylated proteins include members of the Ras, Rab, and Rho families, lamins, CENPE and CENPF, and the gamma subunit of many small heterotrimeric G proteins. This modification is catalyzed by the protein prenyltransferases: protein farnesyltransferase (FTase), protein geranylgeranyltransferase type I (GGTase-I), and GGTase-II (or RabGGTase). In this review, we examine the structural biology of FTase and GGTase-I (the CaaX prenyltransferases) to establish a framework for understanding the molecular basis of substrate specificity and mechanism. These enzymes have been identified in a number of species, including mammals, fungi, plants, and protists. Prenyltransferase structures include complexes that represent the major steps along the reaction path, as well as a number of complexes with clinically relevant inhibitors. Such complexes may assist in the design of inhibitors that could lead to treatments for cancer, viral infection, and a number of deadly parasitic diseases.
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Affiliation(s)
- Kimberly T Lane
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
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23
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Takata T, Shimo-Oka T, Miki K, Fujii N. Characterization of new d-β-aspartate-containing proteins in a lens-derived cell line. Biochem Biophys Res Commun 2005; 334:1022-31. [PMID: 16038880 DOI: 10.1016/j.bbrc.2005.06.195] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Accepted: 06/30/2005] [Indexed: 10/25/2022]
Abstract
Although proteins are generally composed of l-alpha-amino acids, biologically uncommon D-beta-aspartic acid (Asp)-containing proteins have been reported in various tissues from elderly individuals. Our previous study indicated that the N/N1003A cell line, derived from rabbit lens, includes D-beta-Asp-containing proteins of approximately 50 kDa by Western blot analysis of a 2D-gel using a polyclonal antibody that is highly specific for D-beta-Asp-containing proteins. In this study, we identified the D-beta-Asp-containing proteins by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and the Mascot online database searching algorithm. The results indicate that one of these 50 kDa proteins is an enolase showing homology with tau-crystallin. Other D-beta-Asp-containing proteins, which we have recently discovered include lamin A/C, cytoplasmic NADP+-dependent isocitrate dehydrogenase, fructose-bisphosphate aldolase A, aldose reductase, L-lactate dehydrogenase A or calponin H2, phosphoglycerate mutase 1, phosphatidylethanolamine-binding protein, alpha-B-crystallin, and peptidyl-prolyl cis-trans isomerase A (PPlase).
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Affiliation(s)
- Takumi Takata
- Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan, Osaka 590-0494, Japan
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24
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Abstract
Most neuromuscular disorders display only non-specific myopathological features in routine histological preparations. However, a number of proteins, including sarcolemmal, sarcomeric, and nuclear proteins as well as enzymes with defects responsible for neuromuscular disorders, have been identified during the past two decades, allowing a more specific and firm diagnosis of muscle diseases. Identification of protein defects relies predominantly on immunohistochemical preparations and on Western blot analysis. While immunohistochemistry is very useful in identifying abnormal expression of primary protein abnormalities in recessive conditions, it is less helpful in detecting primary defects in dominantly inherited disorders. Abnormal immunohistochemical expression patterns can be confirmed by Western blot analysis which may also be informative in dominant disorders, although its role has yet to be established. Besides identification of specific protein defects, immunohistochemistry is also helpful in the differentiation of inflammatory myopathies by subtyping cellular infiltrates and demonstrating up-regulation of subtle immunological parameters such as cell adhesion molecules. The role of immunohistochemistry in denervating disorders, however, remains controversial in the absence of a reliable marker of muscle fibre denervation. Nevertheless, as well as the diagnostic value of immunocytochemical analysis it may also widen understanding of muscle fibre pathology as well as help in the development of therapeutic strategies.
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Affiliation(s)
- D S Tews
- Edinger-Institute of the Johann-Wolfgang Goethe-University, Frankfurt, Germany.
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25
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Brimah K, Ehrhardt J, Mouly V, Butler-Browne GS, Partridge TA, Morgan JE. Human muscle precursor cell regeneration in the mouse host is enhanced by growth factors. Hum Gene Ther 2005; 15:1109-24. [PMID: 15610611 DOI: 10.1089/hum.2004.15.1109] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to optimize human muscle formation in vivo from implanted human muscle precursor cells. We transplanted donor muscle precursor cells (MPCs) prepared from postnatal or fetal human muscle into immunodeficient host mice and showed that irradiation of host muscle significantly enhanced muscle formation by donor cells. The amount of donor muscle formed in cryodamaged host muscle was increased by exposure of donor cells to growth factors before their implantation into injured host muscle. Insulin-like growth factor type I (IGF-I) significantly increased the amount of muscle formed by postnatal human muscle cells, but not by fetal human MPCs. However, treatment of fetal muscle cells with IGF-I, in combination with basic fibroblast growth factor and plasmin, significantly increased the amount of donor muscle formed. In vivo, human MPCs formed mosaic human-mouse muscle fibers, in which each human myonucleus was associated with a zone of human sarcolemmal protein spectrin.
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Affiliation(s)
- K Brimah
- Muscle Cell Biology Group, MRC Clinical Sciences Centre, Imperial College, London W12 ONN, United Kingdom
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Maraldi NM, Squarzoni S, Sabatelli P, Capanni C, Mattioli E, Ognibene A, Lattanzi G. Laminopathies: Involvement of structural nuclear proteins in the pathogenesis of an increasing number of human diseases. J Cell Physiol 2005; 203:319-27. [PMID: 15389628 DOI: 10.1002/jcp.20217] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Just at the beginning of the millennium the neologism laminopathies has been introduced in the scientific vocabulary. An exponential increase of interest on the subject started concomitantly, so that a formerly quite neglected group of rare human diseases is now widely investigated. This review will cover the history of the identification of the molecular basis for fourteen (since now) hereditary diseases arising from defects in genes that encode nuclear envelope and nuclear lamina-associated proteins and will also consider the hypotheses that can account for the role of structural nuclear proteins in the pathogenesis of diseases affecting a wide spectrum of tissues.
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Affiliation(s)
- Nadir M Maraldi
- ITOI-CNR, Unit of Bologna via di Barbiano 1/10 c/o IOR, 40136 Bologna, Italy.
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Haraguchi T, Holaska JM, Yamane M, Koujin T, Hashiguchi N, Mori C, Wilson KL, Hiraoka Y. Emerin binding to Btf, a death-promoting transcriptional repressor, is disrupted by a missense mutation that causes Emery-Dreifuss muscular dystrophy. ACTA ACUST UNITED AC 2004; 271:1035-45. [PMID: 15009215 DOI: 10.1111/j.1432-1033.2004.04007.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Loss of functional emerin, a nuclear membrane protein, causes X-linked recessive Emery-Dreifuss muscular dystrophy. In a yeast two-hybrid screen, we found that emerin interacts with Btf, a death-promoting transcriptional repressor, which is expressed at high levels in skeletal muscle. Biochemical analysis showed that emerin binds Btf with an equilibrium affinity (KD) of 100 nm. Using a collection of 21 clustered alanine-substitution mutations in emerin, the residues required for binding to Btf mapped to two regions of emerin that flank its lamin-binding domain. Two disease-causing mutations in emerin, S54F and Delta95-99, disrupted binding to Btf. The Delta95-99 mutation was relatively uninformative, as this mutation also disrupts emerin binding to lamin A and a different transcription repressor named germ cell-less (GCL). In striking contrast, emerin mutant S54F, which binds normally to barrier-to-autointegration factor, lamin A and GCL, selectively disrupted emerin binding to Btf. We localized endogenous Btf in HeLa cells by indirect immunoflurorescence using affinity-purified antibodies against Btf. In nonapoptotic HeLa cells Btf was found in dot-like structures throughout the nuclear interior. However, within 3 h after treating cells with Fas antibody to induce apoptosis, the distribution of Btf changed, and Btf concentrated in a distinct zone near the nuclear envelope. These results suggest that Btf localization is regulated by apoptotic signals, and that loss of emerin binding to Btf may be relevant to muscle wasting in Emery-Dreifuss muscular dystrophy.
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Affiliation(s)
- Tokuko Haraguchi
- CREST Research Project, Kansai Advanced Research Center, Communications Research Laboratory, Iwaoka-cho, Nishi-ku, Kobe, Japan.
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Wilkinson FL, Holaska JM, Zhang Z, Sharma A, Manilal S, Holt I, Stamm S, Wilson KL, Morris GE. Emerin interacts in vitro with the splicing-associated factor, YT521-B. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:2459-66. [PMID: 12755701 DOI: 10.1046/j.1432-1033.2003.03617.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Emerin is a nuclear membrane protein that interacts with lamin A/C at the nuclear envelope. Mutations in either emerin or lamin A/C cause Emery-Dreifuss muscular dystrophy (EDMD). The functions of emerin are poorly understood, but EDMD affects mainly skeletal and cardiac muscle. We used a high-stringency yeast two-hybrid method to screen a human heart cDNA library, with full-length emerin as bait. Four out of five candidate interactors identified were nuclear proteins: lamin A, splicing factor YT521-B, proteasome subunit PA28 gamma and transcription factor vav-1. Specific binding between emerin and the functional C-terminal domain of YT521-B was confirmed by pull-down assays and biomolecular interaction analysis (BIAcore). Inhibition by emerin of YT521-B-dependent splice site selection in vivo suggests that the interaction is physiologically significant. A 'bipartite' binding site for YT521-B in emerin was identified using alanine substitution or disease-associated mutations in emerin. The transcription factor GCL (germ cell-less) has previously been shown to bind to the same site. The results are consistent with an emerging view that lamins and lamina-associated proteins, like emerin, have a regulatory role, as well as a structural role in the nucleus. YT521-B joins a growing list of candidates for a role in a gene expression model of the pathogenesis of EDMD.
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Abstract
Mechanisms for nuclear migration and nuclear anchorage function together to control nuclear positioning. Both tubulin and actin networks play important roles in nuclear positioning. The actin cytoskeleton has been shown to position nuclei in a variety of systems from yeast to plants and animals. It can either act as a stable skeleton to anchor nuclei or supply the active force to move nuclei. Two C. elegans genes and their homologues play important roles in these processes. Syne/ANC-1 anchors nuclei by directly tethering the nuclear envelope to the actin cytoskeleton, and UNC-84/SUN functions at the nuclear envelope to recruit Syne/ANC-1.
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Affiliation(s)
- Daniel A Starr
- Howard Hughes Medical Institute and Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309, USA.
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Maraldi NM, Squarzoni S, Sabatelli P, Lattanzi G, Ognibene A, Manzoli FA. Emery-Dreifuss muscular dystrophy, nuclear cell signaling and chromatin remodeling. ADVANCES IN ENZYME REGULATION 2002; 42:1-18. [PMID: 12123703 DOI: 10.1016/s0065-2571(01)00022-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Nadir M Maraldi
- Institute of Citomorfologia Normale e Patologica C.N.R. and Laboratory of Biologia Cellulare e Microscopia Elettronica, I. O. R., Bologna, Italy
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Abstract
The nuclear lamina is composed of both A- and B-type lamins and lamin-binding proteins. Many lamin-binding proteins are integral proteins of the inner nuclear membrane. Lamins and inner nuclear membrane proteins are important for a variety of cell functions, including nuclear assembly, replication, transcription, and nuclear integrity. Recent advances in the field in the past year include the identification of a family of spectrin-repeat-containing inner nuclear membrane proteins and other novel inner-membrane proteins, and the discovery of a nuclear membrane fusion complex. There is also growing evidence that A- and B-type lamins and their binding partners have distinct roles during nuclear assembly and interphase.
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Affiliation(s)
- James M Holaska
- Department of Cell Biology, The Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205, USA
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Vlcek S, Korbei B, Foisner R. Distinct functions of the unique C terminus of LAP2alpha in cell proliferation and nuclear assembly. J Biol Chem 2002; 277:18898-907. [PMID: 11864981 DOI: 10.1074/jbc.m200048200] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The non-membrane-bound lamina-associated polypeptide 2 isoform, LAP2alpha, forms nucleoskeletal structures with A-type lamins and interacts with chromosomes in a cell cycle-dependent manner. LAP2alpha contains a LEM (LAP2, emerin, and MAN1) domain in the constant N terminus that binds to chromosomal barrier-to-autointegration factor, and a C-terminal unique region that is essential for chromosome binding. Here we show that C-terminal LAP2alpha fragment efficiently bound to mitotic chromosomes and inhibited assembly of endogenous LAP2alpha, nuclear membranes, and lamins A/C in in vitro nuclear assembly assays. Full-length recombinant LAP2alpha, which bound to chromosomes, and N-terminal fragment, which did not bind, had no effect on assembly. This suggested an essential role for the LAP2alpha C terminus in chromosome association and for the N-terminal LEM domain in subsequent assembly stages. In vivo analysis upon transient expression of GFP-tagged LAP2alpha fragments confirmed that, unlike the N-terminal fragment, the C-terminal fragment was able to bind to chromosomes during mitosis, if expressed weakly. At higher expression levels, C-terminal LAP2alpha fragment and full-length protein led to cell cycle arrest in interphase and apoptosis, as shown by fluorescence-activated cell sorter analysis, time lapse microscopy, and BrdUrd incorporation assays. These data indicated distinct functions of LAP2alpha in cell cycle progression during interphase and in nuclear reassembly during mitosis.
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Affiliation(s)
- Sylvia Vlcek
- Department of Biochemistry and Molecular Cell Biology, Vienna Biocenter, University of Vienna, A-1030 Vienna, Austria
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Gindullis F, Rose A, Patel S, Meier I. Four signature motifs define the first class of structurally related large coiled-coil proteins in plants. BMC Genomics 2002; 3:9. [PMID: 11972898 PMCID: PMC102765 DOI: 10.1186/1471-2164-3-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2002] [Accepted: 04/09/2002] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Animal and yeast proteins containing long coiled-coil domains are involved in attaching other proteins to the large, solid-state components of the cell. One subgroup of long coiled-coil proteins are the nuclear lamins, which are involved in attaching chromatin to the nuclear envelope and have recently been implicated in inherited human diseases. In contrast to other eukaryotes, long coiled-coil proteins have been barely investigated in plants. RESULTS We have searched the completed Arabidopsis genome and have identified a family of structurally related long coiled-coil proteins. Filament-like plant proteins (FPP) were identified by sequence similarity to a tomato cDNA that encodes a coiled-coil protein which interacts with the nuclear envelope-associated protein, MAF1. The FPP family is defined by four novel unique sequence motifs and by two clusters of long coiled-coil domains separated by a non-coiled-coil linker. All family members are expressed in a variety of Arabidopsis tissues. A homolog sharing the structural features was identified in the monocot rice, indicating conservation among angiosperms. CONCLUSION Except for myosins, this is the first characterization of a family of long coiled-coil proteins in plants. The tomato homolog of the FPP family binds in a yeast two-hybrid assay to a nuclear envelope-associated protein. This might suggest that FPP family members function in nuclear envelope biology. Because the full Arabidopsis genome does not appear to contain genes for lamins, it is of interest to investigate other long coiled-coil proteins, which might functionally replace lamins in the plant kingdom.
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Affiliation(s)
- Frank Gindullis
- CellTec Biotechnologie GmbH, Frohmestrasse 110, D-22459 Hamburg, Germany
| | - Annkatrin Rose
- Plant Biotechnology Center and Department of Plant Biology, Ohio State University, 210 Rightmire Hall, 1060 Carmack Road, Columbus, Ohio 43210, USA
| | - Shalaka Patel
- Plant Biotechnology Center and Department of Plant Biology, Ohio State University, 210 Rightmire Hall, 1060 Carmack Road, Columbus, Ohio 43210, USA
| | - Iris Meier
- Plant Biotechnology Center and Department of Plant Biology, Ohio State University, 210 Rightmire Hall, 1060 Carmack Road, Columbus, Ohio 43210, USA
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Wu W, Lin F, Worman HJ. Intracellular trafficking of MAN1, an integral protein of the nuclear envelope inner membrane. J Cell Sci 2002; 115:1361-71. [PMID: 11896184 DOI: 10.1242/jcs.115.7.1361] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
MAN1 is an integral protein of the inner nuclear membrane that shares the LEM domain, a conserved globular domain of approximately 40 amino acids, with lamina-associated polypeptide (LAP) 2 and emerin. Confocal immuofluorescence microscopy studies of the intracellular targeting of truncated forms of MAN1 showed that the nucleoplasmic, N-terminal domain is necessary for inner nuclear membrane retention. A protein containing the N-terminal domain with the first transmembrane segment of MAN1 is retained in the inner nuclear membrane, whereas the transmembrane segments with the C-terminal domain of MAN1 is not targeted to the inner nuclear membrane. The N-terminal domain of MAN1 is also sufficient for inner nuclear membrane targeting as it can target a chimeric type II integral protein to this subcellular location. Deletion mutants of the N-terminal of MAN1 are not efficiently retained in the inner nuclear membrane. When the N-terminal domain of MAN1 is increased in size from∼50 kDa to ∼100 kDa, the protein cannot reach the inner nuclear membrane. Fluorescence recovery after photobleaching experiments of MAN1 fused to green fluorescent protein show that the fusion protein is relatively immobile in the nuclear envelope compared with the endoplasmic reticulum of interphase cells, suggesting binding to a nuclear component. These results are in agreement with the `diffusion-retention' model for targeting integral proteins to the inner nuclear membrane.
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Affiliation(s)
- Wei Wu
- Departments of Medicine and of Anatomy and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA
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Abstract
Characterization of the mechanisms underlying various types of muscular dystrophy has been an outstanding triumph of molecular biology. Increasing clarification of the aberrant cellular processes responsible for these conditions may ultimately permit the development of effective means for molecular intervention, allowing correction of the abnormal cellular physiology that results in the dystrophic phenotype.
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Affiliation(s)
- Edward A Burton
- Department of Clinical Neurology, University of Oxford, Oxford OX1 3QX, United Kingdom
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Mislow JMK, Kim MS, Davis DB, McNally EM. Myne-1, a spectrin repeat transmembrane protein of the myocyte inner nuclear membrane, interacts with lamin A/C. J Cell Sci 2002; 115:61-70. [PMID: 11801724 DOI: 10.1242/jcs.115.1.61] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mutations in the genes encoding the inner nuclear membrane proteins lamin A/C and emerin produce cardiomyopathy and muscular dystrophy in humans and mice. The mechanism by which these broadly expressed gene products result in tissue-specific dysfunction is not known. We have identified a protein of the inner nuclear membrane that is highly expressed in striated and smooth muscle. This protein, myne-1 (myocyte nuclear envelope), is predicted to have seven spectrin repeats, an interrupted LEM domain and a single transmembrane domain at its C-terminus. We found that myne-1 is expressed upon early muscle differentiation in multiple intranuclear foci concomitant with lamin A/C expression. In mature muscle, myne-1 and lamin A/C are perfectly colocalized, although colocalization with emerin is only partial. Moreover, we show that myne-1 and lamin A/C coimmunoprecipitate from differentiated muscle in vitro. The muscle-specific inner nuclear envelope expression of myne-1, along with its interaction with lamin A/C, indicates that this gene is a potential mediator of cardiomyopathy and muscular dystrophy.
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Affiliation(s)
- John M K Mislow
- Department of Pathology, The University of Chicago, Chicago, IL 60637, USA
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Wright R, Boggs J. Learning cell biology as a team: a project-based approach to upper-division cell biology. CELL BIOLOGY EDUCATION 2002; 1:145-53. [PMID: 12669105 PMCID: PMC149487 DOI: 10.1187/cbe.02-03-0006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2002] [Revised: 07/22/2002] [Accepted: 07/29/2002] [Indexed: 12/17/2022]
Abstract
To help students develop successful strategies for learning how to learn and communicate complex information in cell biology, we developed a quarter-long cell biology class based on team projects. Each team researches a particular human disease and presents information about the cellular structure or process affected by the disease, the cellular and molecular biology of the disease, and recent research focused on understanding the cellular mechanisms of the disease process. To support effective teamwork and to help students develop collaboration skills useful for their future careers, we provide training in working in small groups. A final poster presentation, held in a public forum, summarizes what students have learned throughout the quarter. Although student satisfaction with the course is similar to that of standard lecture-based classes, a project-based class offers unique benefits to both the student and the instructor.
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Affiliation(s)
- Robin Wright
- Department of Zoology, University of Washington, Seattle, Washington 98195, USA.
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