1
|
Storey EC, Holt I, Brown S, Synowsky S, Shirran S, Fuller HR. Proteomic characterization of human LMNA-related congenital muscular dystrophy muscle cells. Neuromuscul Disord 2024; 38:26-41. [PMID: 38554696 DOI: 10.1016/j.nmd.2024.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 03/08/2024] [Accepted: 03/11/2024] [Indexed: 04/02/2024]
Abstract
LMNA-related congenital muscular dystrophy (L-CMD) is caused by mutations in the LMNA gene, encoding lamin A/C. To further understand the molecular mechanisms of L-CMD, proteomic profiling using DIA mass spectrometry was conducted on immortalized myoblasts and myotubes from controls and L-CMD donors each harbouring a different LMNA mutation (R249W, del.32 K and L380S). Compared to controls, 124 and 228 differentially abundant proteins were detected in L-CMD myoblasts and myotubes, respectively, and were associated with enriched canonical pathways including synaptogenesis and necroptosis in myoblasts, and Huntington's disease and insulin secretion in myotubes. Abnormal nuclear morphology and reduced lamin A/C and emerin abundance was evident in all L-CMD cell lines compared to controls, while nucleoplasmic aggregation of lamin A/C was restricted to del.32 K cells, and mislocalization of emerin was restricted to R249W cells. Abnormal nuclear morphology indicates loss of nuclear lamina integrity as a common feature of L-CMD, likely rendering muscle cells vulnerable to mechanically induced stress, while differences between L-CMD cell lines in emerin and lamin A localization suggests that some molecular alterations in L-CMD are mutation specific. Nonetheless, identifying common proteomic alterations and molecular pathways across all three L-CMD lines has highlighted potential targets for the development of non-mutation specific therapies.
Collapse
Affiliation(s)
- Emily C Storey
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK
| | - Ian Holt
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK
| | - Sharon Brown
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK
| | - Silvia Synowsky
- BSRC Mass Spectrometry and Proteomics Facility, University of St Andrews, KY16 9ST, UK
| | - Sally Shirran
- BSRC Mass Spectrometry and Proteomics Facility, University of St Andrews, KY16 9ST, UK
| | - Heidi R Fuller
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK.
| |
Collapse
|
2
|
Bihani A, Avvaru AK, Mishra RK. Biochemical Deconstruction and Reconstruction of Nuclear Matrix Reveals the Layers of Nuclear Organization. Mol Cell Proteomics 2023; 22:100671. [PMID: 37863319 PMCID: PMC10687341 DOI: 10.1016/j.mcpro.2023.100671] [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: 08/30/2023] [Revised: 10/11/2023] [Accepted: 10/15/2023] [Indexed: 10/22/2023] Open
Abstract
Nuclear matrix (NuMat) is the fraction of the eukaryotic nucleus insoluble to detergents and high-salt extractions that manifests as a pan-nuclear fiber-granule network. NuMat consists of ribonucleoprotein complexes, members of crucial nuclear functional modules, and DNA fragments. Although NuMat captures the organization of nonchromatin nuclear space, very little is known about components organization within NuMat. To understand the organization of NuMat components, we subfractionated it with increasing concentrations of the chaotrope guanidinium hydrochloride (GdnHCl) and analyzed the proteomic makeup of the fractions. We observe that the solubilization of proteins at different concentrations of GdnHCl is finite and independent of the broad biophysical properties of the protein sequences. Looking at the extraction pattern of the nuclear envelope and nuclear pore complex, we surmise that this fractionation represents easily solubilized/loosely bound and difficultly solubilized/tightly bound components of NuMat. Microscopic analyses of the localization of key NuMat proteins across sequential GdnHCl extractions of in situ NuMat further elaborate on the divergent extraction patterns. Furthermore, we solubilized NuMat in 8M GdnHCl and upon removal of GdnHCl through dialysis, en masse renaturation leads to RNA-dependent self-assembly of fibrous structures. The major proteome component of the self-assembled fibers comes from the difficultly solubilized, tightly bound component. This fractionation of the NuMat reveals different organizational levels within it which may reflect the structural and functional organization of nuclear architecture.
Collapse
Affiliation(s)
- Ashish Bihani
- CSIR - Centre for Cellular and Molecular Biology (CCMB), Hyderabad, India.
| | - Akshay K Avvaru
- CSIR - Centre for Cellular and Molecular Biology (CCMB), Hyderabad, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Rakesh K Mishra
- CSIR - Centre for Cellular and Molecular Biology (CCMB), Hyderabad, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India; Tata Institute for Genetics and Society (TIGS), Bengaluru, India.
| |
Collapse
|
3
|
Kim HJ, Lee PCW, Hong JH. Overview of cellular homeostasis-associated nuclear envelope lamins and associated input signals. Front Cell Dev Biol 2023; 11:1173514. [PMID: 37250905 PMCID: PMC10213260 DOI: 10.3389/fcell.2023.1173514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/03/2023] [Indexed: 05/31/2023] Open
Abstract
With the discovery of the role of the nuclear envelope protein lamin in human genetic diseases, further diverse roles of lamins have been elucidated. The roles of lamins have been addressed in cellular homeostasis including gene regulation, cell cycle, cellular senescence, adipogenesis, bone remodeling as well as modulation of cancer biology. Features of laminopathies line with oxidative stress-associated cellular senescence, differentiation, and longevity and share with downstream of aging-oxidative stress. Thus, in this review, we highlighted various roles of lamin as key molecule of nuclear maintenance, specially lamin-A/C, and mutated LMNA gene clearly reveal aging-related genetic phenotypes, such as enhanced differentiation, adipogenesis, and osteoporosis. The modulatory roles of lamin-A/C in stem cell differentiation, skin, cardiac regulation, and oncology have also been elucidated. In addition to recent advances in laminopathies, we highlighted for the first kinase-dependent nuclear lamin biology and recently developed modulatory mechanisms or effector signals of lamin regulation. Advanced knowledge of the lamin-A/C proteins as diverse signaling modulators might be biological key to unlocking the complex signaling of aging-related human diseases and homeostasis in cellular process.
Collapse
Affiliation(s)
- Hyeong Jae Kim
- Department of Physiology, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon, Republic of Korea
| | - Peter C. W. Lee
- Lung Cancer Research Center, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Republic of Korea
| | - Jeong Hee Hong
- Department of Physiology, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon, Republic of Korea
| |
Collapse
|
4
|
Guan G, Cannon RD, Coates DE, Mei L. Effect of the Rho-Kinase/ROCK Signaling Pathway on Cytoskeleton Components. Genes (Basel) 2023; 14:272. [PMID: 36833199 PMCID: PMC9957420 DOI: 10.3390/genes14020272] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/10/2023] [Accepted: 01/16/2023] [Indexed: 01/22/2023] Open
Abstract
The mechanical properties of cells are important in tissue homeostasis and enable cell growth, division, migration and the epithelial-mesenchymal transition. Mechanical properties are determined to a large extent by the cytoskeleton. The cytoskeleton is a complex and dynamic network composed of microfilaments, intermediate filaments and microtubules. These cellular structures confer both cell shape and mechanical properties. The architecture of the networks formed by the cytoskeleton is regulated by several pathways, a key one being the Rho-kinase/ROCK signaling pathway. This review describes the role of ROCK (Rho-associated coiled-coil forming kinase) and how it mediates effects on the key components of the cytoskeleton that are critical for cell behaviour.
Collapse
Affiliation(s)
- Guangzhao Guan
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Department of Oral Diagnostic and Surgical Sciences, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Richard D. Cannon
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Dawn E. Coates
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Li Mei
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| |
Collapse
|
5
|
Zheng M, Jin G, Zhou Z. Post-Translational Modification of Lamins: Mechanisms and Functions. Front Cell Dev Biol 2022; 10:864191. [PMID: 35656549 PMCID: PMC9152177 DOI: 10.3389/fcell.2022.864191] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/17/2022] [Indexed: 12/22/2022] Open
Abstract
Lamins are the ancient type V intermediate filament proteins contributing to diverse biological functions, such as the maintenance of nuclear morphology, stabilization of chromatin architecture, regulation of cell cycle progression, regulation of spatial-temporal gene expressions, and transduction of mechano-signaling. Deregulation of lamins is associated with abnormal nuclear morphology and chromatin disorganization, leading to a variety of diseases such as laminopathy and premature aging, and might also play a role in cancer. Accumulating evidence indicates that lamins are functionally regulated by post-translational modifications (PTMs) including farnesylation, phosphorylation, acetylation, SUMOylation, methylation, ubiquitination, and O-GlcNAcylation that affect protein stabilization and the association with chromatin or associated proteins. The mechanisms by which these PTMs are modified and the relevant functionality become increasingly appreciated as understanding of these changes provides new insights into the molecular mechanisms underlying the laminopathies concerned and novel strategies for the management. In this review, we discussed a range of lamin PTMs and their roles in both physiological and pathological processes, as well as potential therapeutic strategies by targeting lamin PTMs.
Collapse
Affiliation(s)
- Mingyue Zheng
- Medical Research Center, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Guoxiang Jin
- Medical Research Center, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhongjun Zhou
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| |
Collapse
|
6
|
Malashicheva A, Perepelina K. Diversity of Nuclear Lamin A/C Action as a Key to Tissue-Specific Regulation of Cellular Identity in Health and Disease. Front Cell Dev Biol 2021; 9:761469. [PMID: 34722546 PMCID: PMC8548693 DOI: 10.3389/fcell.2021.761469] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/20/2021] [Indexed: 12/12/2022] Open
Abstract
A-type lamins are the main structural components of the nucleus, which are mainly localized at the nucleus periphery. First of all, A-type lamins, together with B-type lamins and proteins of the inner nuclear membrane, form a stiff structure-the nuclear lamina. Besides maintaining the nucleus cell shape, A-type lamins play a critical role in many cellular events, such as gene transcription and epigenetic regulation. Nowadays it is clear that lamins play a very important role in determining cell fate decisions. Various mutations in genes encoding A-type lamins lead to damages of different types of tissues in humans, collectively known as laminopathies, and it is clear that A-type lamins are involved in the regulation of cell differentiation and stemness. However, the mechanisms of this regulation remain unclear. In this review, we discuss how A-type lamins can execute their regulatory role in determining the differentiation status of a cell. We have summarized recent data focused on lamin A/C action mechanisms in regulation of cell differentiation and identity development of stem cells of different origin. We also discuss how this knowledge can promote further research toward a deeper understanding of the role of lamin A/C mutations in laminopathies.
Collapse
Affiliation(s)
- Anna Malashicheva
- Laboratory of Regenerative Biomedicine, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
| | - Kseniya Perepelina
- Laboratory of Regenerative Biomedicine, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
| |
Collapse
|
7
|
Gatti G, Vilardo L, Musa C, Di Pietro C, Bonaventura F, Scavizzi F, Torcinaro A, Bucci B, Saporito R, Arisi I, De Santa F, Raspa M, Guglielmi L, D’Agnano I. Role of Lamin A/C as Candidate Biomarker of Aggressiveness and Tumorigenicity in Glioblastoma Multiforme. Biomedicines 2021; 9:biomedicines9101343. [PMID: 34680461 PMCID: PMC8533312 DOI: 10.3390/biomedicines9101343] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/21/2021] [Accepted: 09/24/2021] [Indexed: 12/11/2022] Open
Abstract
Nuclear lamina components have long been regarded as scaffolding proteins, forming a dense fibrillar structure necessary for the maintenance of the nucleus shape in all the animal kingdom. More recently, mutations, aberrant localisation and deregulation of these proteins have been linked to several diseases, including cancer. Using publicly available data we found that the increased expression levels of the nuclear protein Lamin A/C correlate with a reduced overall survival in The Cancer Genome Atlas Research Network (TCGA) patients affected by glioblastoma multiforme (GBM). We show that the expression of the LMNA gene is linked to the enrichment of cancer-related pathways, particularly pathways related to cell adhesion and cell migration. Mimicking the modulation of LMNA in a GBM preclinical cancer model, we confirmed both in vitro and in vivo that the increased expression of LMNA is associated with an increased aggressiveness and tumorigenicity. In addition, delving into the possible mechanism behind LMNA-induced GBM aggressiveness and tumorigenicity, we found that the mTORC2 component, Rictor, plays a central role in mediating these effects.
Collapse
Affiliation(s)
- Giuliana Gatti
- Department of Biotechnology and Translational Medicine, University of Milan, 20129 Milan, Italy;
| | - Laura Vilardo
- Institute for Biomedical Technologies (ITB), CNR, 20054 Segrate, Italy; (L.V.); (C.M.)
| | - Carla Musa
- Institute for Biomedical Technologies (ITB), CNR, 20054 Segrate, Italy; (L.V.); (C.M.)
| | - Chiara Di Pietro
- Institute of Biochemistry and Cell Biology (IBBC), CNR, 00015 Monterotondo, Italy; (C.D.P.); (F.B.); (F.S.); (A.T.); (F.D.S.); (M.R.)
| | - Fabrizio Bonaventura
- Institute of Biochemistry and Cell Biology (IBBC), CNR, 00015 Monterotondo, Italy; (C.D.P.); (F.B.); (F.S.); (A.T.); (F.D.S.); (M.R.)
| | - Ferdinando Scavizzi
- Institute of Biochemistry and Cell Biology (IBBC), CNR, 00015 Monterotondo, Italy; (C.D.P.); (F.B.); (F.S.); (A.T.); (F.D.S.); (M.R.)
| | - Alessio Torcinaro
- Institute of Biochemistry and Cell Biology (IBBC), CNR, 00015 Monterotondo, Italy; (C.D.P.); (F.B.); (F.S.); (A.T.); (F.D.S.); (M.R.)
| | - Barbara Bucci
- UOC Clinical Pathology, San Pietro Hospital FBF, 00189 Rome, Italy; (B.B.); (R.S.)
| | - Raffaele Saporito
- UOC Clinical Pathology, San Pietro Hospital FBF, 00189 Rome, Italy; (B.B.); (R.S.)
| | - Ivan Arisi
- Bioinformatics Facility, European Brain Research Institute (EBRI) “Rita Levi Montalcini”, 00161 Rome, Italy;
| | - Francesca De Santa
- Institute of Biochemistry and Cell Biology (IBBC), CNR, 00015 Monterotondo, Italy; (C.D.P.); (F.B.); (F.S.); (A.T.); (F.D.S.); (M.R.)
| | - Marcello Raspa
- Institute of Biochemistry and Cell Biology (IBBC), CNR, 00015 Monterotondo, Italy; (C.D.P.); (F.B.); (F.S.); (A.T.); (F.D.S.); (M.R.)
| | - Loredana Guglielmi
- Institute for Biomedical Technologies (ITB), CNR, 20054 Segrate, Italy; (L.V.); (C.M.)
- Correspondence: (L.G.); (I.D.)
| | - Igea D’Agnano
- Institute for Biomedical Technologies (ITB), CNR, 20054 Segrate, Italy; (L.V.); (C.M.)
- Correspondence: (L.G.); (I.D.)
| |
Collapse
|
8
|
Dong CH, Jiang T, Yin H, Song H, Zhang Y, Geng H, Shi PC, Xu YX, Gao H, Liu LY, Zhou L, Zhang ZH, Song J. LMNB2 promotes the progression of colorectal cancer by silencing p21 expression. Cell Death Dis 2021; 12:331. [PMID: 33782407 PMCID: PMC8007612 DOI: 10.1038/s41419-021-03602-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 02/22/2021] [Accepted: 03/01/2021] [Indexed: 02/07/2023]
Abstract
Colorectal cancer is the second common cause of death worldwide. Lamin B2 (LMNB2) is involved in chromatin remodeling and the rupture and reorganization of nuclear membrane during mitosis, which is necessary for eukaryotic cell proliferation. However, the role of LMNB2 in colorectal cancer (CRC) is poorly understood. This study explored the biological functions of LMNB2 in the progression of colorectal cancer and explored the possible molecular mechanisms. We found that LMNB2 was significantly upregulated in primary colorectal cancer tissues and cell lines, compared with paired non-cancerous tissues and normal colorectal epithelium. The high expression of LMNB2 in colorectal cancer tissues is significantly related to the clinicopathological characteristics of the patients and the shorter overall and disease-free cumulative survival. Functional analysis, including CCK8 cell proliferation test, EdU proliferation test, colony formation analysis, nude mouse xenograft, cell cycle, and apoptosis analysis showed that LMNB2 significantly promotes cell proliferation by promoting cell cycle progression in vivo and in vitro. In addition, gene set enrichment analysis, luciferase report analysis, and CHIP analysis showed that LMNB2 promotes cell proliferation by regulating the p21 promoter, whereas LMNB2 has no effect on cell apoptosis. In summary, these findings not only indicate that LMNB2 promotes the proliferation of colorectal cancer by regulating p21-mediated cell cycle progression, but also suggest the potential value of LMNB2 as a clinical prognostic marker and molecular therapy target.
Collapse
Affiliation(s)
- Chen-Hua Dong
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- The Graduate School, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Tao Jiang
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- Institute of Digestive Diseases, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Hang Yin
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- The Graduate School, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Hu Song
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- Institute of Digestive Diseases, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Yi Zhang
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- Institute of Digestive Diseases, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Hao Geng
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- The Graduate School, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Pei-Cong Shi
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- Institute of Digestive Diseases, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Yi-Xin Xu
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- Institute of Digestive Diseases, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Hong Gao
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- Institute of Digestive Diseases, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Lian-Yu Liu
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- The Graduate School, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Lei Zhou
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China
- The Graduate School, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Zhao-Hui Zhang
- General Surgery, 97th Hospital of Chinese People's Liberation Army, Xuzhou, 221004, China.
| | - Jun Song
- Department of General Surgery, The Affiliated Hospital of Xuzhou Medical University, Jiangsu, 221002, Xuzhou, China.
- The Graduate School, Xuzhou Medical University, Xuzhou, Jiangsu, China.
| |
Collapse
|
9
|
Tran RDH, Siemens M, Nguyen CHH, Ochs AR, Zaragoza MV, Grosberg A. The Effect of Cyclic Strain on Human Fibroblasts With Lamin A/C Mutations and Its Relation to Heart Disease. J Biomech Eng 2020; 142:2737114. [PMID: 31233093 DOI: 10.1115/1.4044091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Indexed: 12/26/2022]
Abstract
Although mutations in the Lamin A/C gene (LMNA) cause a variety of devastating diseases, the pathological mechanism is often unknown. Lamin A/C proteins play a crucial role in forming a meshwork under the nuclear membrane, providing the nucleus with mechanical integrity and interacting with other proteins for gene regulation. Most LMNA mutations result in heart diseases, including some types that primarily have heart disease as the main pathology. In this study, we used cells from patients with different LMNA mutations that primarily lead to heart disease. Indeed, it is a mystery why a mutation to the protein in every nucleus of the body manifests as a disease of primarily the heart in these patients. Here, we aimed to investigate if strains mimicking those within the myocardial environment are sufficient to cause differences in cells with and without the LMNA mutation. To test this, a stretcher device was used to induce cyclic strain upon cells, and viability/proliferation, cytoskeleton and extracellular matrix organization, and nuclear morphology were quantified. The properties of cells with Hutchinson-Gilford progeria syndrome (HGPS) were found to be significantly different from all other cell lines and were mostly in line with previous findings. However, the properties of cells from patients who primarily had heart diseases were not drastically different when compared to individuals without the LMNA mutation. Our results indicated that cyclic strain alone was insufficient to cause any significant differences that could explain the mechanisms that lead to heart diseases in these patients with LMNA mutations.
Collapse
Affiliation(s)
- Richard D H Tran
- Cardiovascular Modeling Laboratory, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, Department of Biomedical Engineering, University of California, 2131 Engineering Hall Irvine, Irvine, CA 92697-2700
| | - Mark Siemens
- Cardiovascular Modeling Laboratory, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, Department of Biomedical Engineering, University of California, 2131 Engineering Hall Irvine, Irvine, CA 92697-2700
| | - Cecilia H H Nguyen
- Division of Genetics and Genomics, Department of Pediatrics, School of Medicine, University of California, 2042 Hewitt Hall Irvine, Irvine, CA 92697-3940
| | - Alexander R Ochs
- Cardiovascular Modeling Laboratory, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, Department of Biomedical Engineering, University of California, 2131 Engineering Hall Irvine, Irvine, CA 92697-2700
| | - Michael V Zaragoza
- Department of Pediatrics, Division of Genetics & Genomics, 2042 Hewitt Hall Irvine, Irvine, CA 92697-3940; Department of Biological Chemistry, University of California, School of Medicine, 2042 Hewitt Hall Irvine, Irvine, CA 92697-3940
| | - Anna Grosberg
- Cardiovascular Modeling Laboratory, The Edwards Lifesciences Center for Advanced Cardiovascular Technology, Center for Complex Biological Systems, Department of Biomedical Engineering, University of California, 2418 Engineering Hall Irvine, Irvine, CA 92697-2700; Department of Chemical and Biomolecular Engineering, University of California, 2418 Engineering Hall Irvine, Irvine, CA 92697-2700
| |
Collapse
|
10
|
Lamin A/C Assembly Defects in LMNA-Congenital Muscular Dystrophy Is Responsible for the Increased Severity of the Disease Compared with Emery-Dreifuss Muscular Dystrophy. Cells 2020; 9:cells9040844. [PMID: 32244403 PMCID: PMC7226786 DOI: 10.3390/cells9040844] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/24/2020] [Accepted: 03/27/2020] [Indexed: 01/13/2023] Open
Abstract
LMNA encodes for Lamin A/C, type V intermediate filaments that polymerize under the inner nuclear membrane to form the nuclear lamina. A small fraction of Lamin A/C, less polymerized, is also found in the nucleoplasm. Lamin A/C functions include roles in nuclear resistance to mechanical stress and gene regulation. LMNA mutations are responsible for a wide variety of pathologies, including Emery–Dreifuss (EDMD) and LMNA-related congenital muscular dystrophies (L-CMD) without clear genotype–phenotype correlations. Both diseases presented with striated muscle disorders although L-CMD symptoms appear much earlier and are more severe. Seeking for pathomechanical differences to explain the severity of L-CMD mutations, we performed an in silico analysis of the UMD-LMNA database and found that L-CMD mutations mainly affect residues involved in Lamin dimer and tetramer stability. In line with this, we found increased nucleoplasmic Lamin A/C in L-CMD patient fibroblasts and mouse myoblasts compared to the control and EDMD. L-CMD myoblasts show differentiation defects linked to their inability to upregulate muscle specific nuclear envelope (NE) proteins expression. NE proteins were mislocalized, leading to misshapen nuclei. We conclude that these defects are due to both the absence of Lamin A/C from the nuclear lamina and its maintenance in the nucleoplasm of myotubes.
Collapse
|
11
|
|
12
|
E3 ubiquitin ligase HECW2 mediates the proteasomal degradation of HP1 isoforms. Biochem Biophys Res Commun 2018; 503:2478-2484. [DOI: 10.1016/j.bbrc.2018.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 07/02/2018] [Indexed: 12/12/2022]
|
13
|
Krishnamoorthy V, Khanna R, Parnaik VK. E3 ubiquitin ligase HECW2 targets PCNA and lamin B1. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2018; 1865:1088-1104. [PMID: 29753763 DOI: 10.1016/j.bbamcr.2018.05.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 04/20/2018] [Accepted: 05/07/2018] [Indexed: 12/21/2022]
Abstract
Lamins constitute the major architectural proteins of the nuclear lamina that help in maintaining nuclear organization. Mutations in lamins are associated with diverse degenerative diseases, collectively termed laminopathies. HECW2, a HECT-type E3 ubiquitin ligase, is transcriptionally upregulated in HeLa cells expressing Emery-Dreifuss muscular dystrophy-causing-lamin A mutants. However, the role of HECW2 upregulation in mediating downstream effects in lamin mutant-expressing cells was previously unexplored. Here, we show that HECW2 interacts with two lamin A-binding proteins, proliferating cell nuclear antigen (PCNA), via a canonical PCNA-interacting protein (PIP) motif, and lamin B1. HECW2 mediates their ubiquitination and targets them for proteasomal degradation. Cells expressing lamin A mutants G232E and Q294P, in which HECW2 is upregulated, show increased proteasomal degradation of PCNA and lamin B1 most likely mediated by HECW2. Our findings establish HECW2 as an E3 ubiquitin ligase for PCNA and lamin B1 which regulates their levels in laminopathic cells. We also found that HECW2 interacts with wild-type lamin A and ubiquitinates it and this interaction is reduced in case of lamin mutants G232E and Q294P. Our findings suggest that interplay among HECW2, lamin A, PCNA, and lamin B1 determines their respective homeostatic levels in the cell and dysregulation of these interactions may contribute to the pathogenicity of laminopathies.
Collapse
Affiliation(s)
| | - Richa Khanna
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Veena K Parnaik
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India.
| |
Collapse
|
14
|
Khanna R, Krishnamoorthy V, Parnaik VK. E3 ubiquitin ligase RNF123 targets lamin B1 and lamin-binding proteins. FEBS J 2018; 285:2243-2262. [PMID: 29676528 DOI: 10.1111/febs.14477] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 03/26/2018] [Accepted: 04/13/2018] [Indexed: 12/27/2022]
Abstract
Lamins are key nuclear proteins which are important for maintaining nuclear structure and function. Mutations in lamins cause a spectrum of genetic diseases termed as laminopathies. RING finger containing E3 ubiquitin ligase, RNF123, is transcriptionally upregulated in cells expressing rod domain lamin A mutations. However, the functional relevance of RNF123 in laminopathic cells is not clear. Using a mass spectrometry-based approach, we identified lamins and lamin-binding proteins retinoblastoma protein (pRb), lamina-associated polypeptide 2α (LAP2α), and emerin as RNF123-interacting proteins. We determined that RNF123 mediated the ubiquitination of these proteins and caused the proteasomal degradation of pRb, LAP2α, and lamin B1. Furthermore, these proteins were also targeted for proteasomal degradation in cells expressing lamin A rod domain mutants G232E, Q294P, and R386K. Overexpression of RNF123 resulted in delayed transit through the S-phase which was alleviated by coexpression of pRb or LAP2α. Our findings imply that RNF123-mediated ubiquitination of lamin-binding proteins may contribute to disease-causing mechanisms in laminopathies by depletion of key nuclear proteins and defects in cell cycle kinetics.
Collapse
Affiliation(s)
- Richa Khanna
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - Veena K Parnaik
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| |
Collapse
|
15
|
Bermeo S, Al-Saedi A, Kassem M, Vidal C, Duque G. The Role of the Nuclear Envelope Protein MAN1 in Mesenchymal Stem Cell Differentiation. J Cell Biochem 2017; 118:4425-4435. [PMID: 28449239 DOI: 10.1002/jcb.26096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 04/26/2017] [Indexed: 01/09/2023]
Abstract
Mutations in MAN1, a protein of the nuclear envelope, cause bone phenotypes characterized by hyperostosis. The mechanism of this pro-osteogenic phenotype remains unknown. We increased and decreased MAN1 expression in mesenchymal stem cells (MSC) upon which standard osteogenic and adipogenic differentiation were performed. MAN1 knockdown increased osteogenesis and mineralization. In contrast, osteogenesis remained stable upon MAN1 overexpression. Regarding a mechanism, we found that low levels of MAN1 facilitated the nuclear accumulation of regulatory smads and smads-related complexes, with a concurrently high expression of nuclear β-Catenin. In addition, we found adipogenesis to be decreased in both conditions, although predominantly affected by MAN1 overexpression. Finally, lamin A, a protein of the nuclear envelope that regulates MSC differentiation, was unaffected by changes in MAN1. In conclusion, our studies demonstrated that lower levels of MAN1 in differentiating MSC are associated with higher osteogenesis and lower adipogenesis. High levels of MAN1 only affected adipogenesis. These effects could have an important role in the understanding of the role of the proteins of the nuclear envelope in bone formation. J. Cell. Biochem. 118: 4425-4435, 2017. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Sandra Bermeo
- Sydney Medical School Nepean, The University of Sydney, Penrith, NSW, Australia.,Facultad de Ciencias Básicas y Biomédicas, Universidad Simón Bolívar, Barranquilla, Colombia
| | - Ahmed Al-Saedi
- Australian Institute for Musculoskeletal Science (AIMSS), The University of Melbourne and Western Health, Melbourne, VIC, Australia.,Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, VIC, Australia
| | - Moustapha Kassem
- Department of Endocrinology and Metabolism, Odense University Hospital & University of Southern Denmark, J.B. Odense C, Denmark
| | - Christopher Vidal
- Sydney Medical School Nepean, The University of Sydney, Penrith, NSW, Australia
| | - Gustavo Duque
- Australian Institute for Musculoskeletal Science (AIMSS), The University of Melbourne and Western Health, Melbourne, VIC, Australia.,Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, VIC, Australia
| |
Collapse
|
16
|
Verma AD, Parnaik VK. Heart-specific expression of laminopathic mutations in transgenic zebrafish. Cell Biol Int 2017; 41:809-819. [DOI: 10.1002/cbin.10784] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/28/2017] [Indexed: 11/07/2022]
Affiliation(s)
- Ajay D. Verma
- CSIR-Centre for Cellular and Molecular Biology; Uppal Road Hyderabad 500007 India
| | - Veena K. Parnaik
- CSIR-Centre for Cellular and Molecular Biology; Uppal Road Hyderabad 500007 India
| |
Collapse
|
17
|
Underwood JM, Becker KA, Stein GS, Nickerson JA. The Ultrastructural Signature of Human Embryonic Stem Cells. J Cell Biochem 2016; 118:764-774. [PMID: 27632380 DOI: 10.1002/jcb.25736] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 09/13/2016] [Indexed: 12/11/2022]
Abstract
The epigenetics and molecular biology of human embryonic stem cells (hES cells) have received much more attention than their architecture. We present a more complete look at hES cells by electron microscopy, with a special emphasis on the architecture of the nucleus. We propose that there is an ultrastructural signature of pluripotent human cells. hES cell nuclei lack heterochromatin, including the peripheral heterochromatin, that is common in most somatic cell types. The absence of peripheral heterochromatin may be related to the absence of lamins A and C, proteins important for linking chromatin to the nuclear lamina and envelope. Lamins A and C expression and the development of peripheral heterochromatin were early steps in the development of embryoid bodies. While hES cell nuclei had abundant nuclear pores, they also had an abundance of nuclear pores in the cytoplasm in the form of annulate lamellae. These were not a residue of annulate lamellae from germ cells or the early embryos from which hES cells were derived. Subnuclear structures including nucleoli, interchromatin granule clusters, and Cajal bodies were observed in the nuclear interior. The architectural organization of human ES cell nuclei has important implications for cell structure-gene expression relationships and for the maintenance of pluripotency. J. Cell. Biochem. 118: 764-774, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Jean M Underwood
- Department of Cell and Developmental Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655
| | - Klaus A Becker
- Department of Cell and Developmental Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655
| | - Gary S Stein
- Department of Cell and Developmental Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655.,Department of Biochemistry and Vermont Cancer Center for Basic and Translational Research, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, Vermont 05405
| | - Jeffrey A Nickerson
- Department of Cell and Developmental Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655
| |
Collapse
|
18
|
Sakthivel KM, Sehgal P. A Novel Role of Lamins from Genetic Disease to Cancer Biomarkers. Oncol Rev 2016; 10:309. [PMID: 27994771 PMCID: PMC5136755 DOI: 10.4081/oncol.2016.309] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 11/03/2016] [Accepted: 11/04/2016] [Indexed: 12/22/2022] Open
Abstract
Lamins are the key components of the nuclear lamina and by virtue of their interactions with chromatin and binding partners act as regulators of cell proliferation and differentiation. Of late, the diverse roles of lamins in cellular processes have made them the topic of intense debate for their role in cancer progression. The observations about aberrant localization or misexpression of the nuclear lamins in cancerous tissues have often led to the speculative role of lamins as a cancer risk biomarker. Here we discuss the involvement of lamins in several cancer subtypes and their potential role in predicting the tumor progression.
Collapse
Affiliation(s)
| | - Poonam Sehgal
- Chemical and Biomolecular Engineering, University of Illinois , Urbana-Champaign, IL, USA
| |
Collapse
|
19
|
Carvalho LO, Aquino EN, Neves ACD, Fontes W. The Neutrophil Nucleus and Its Role in Neutrophilic Function. J Cell Biochem 2016; 116:1831-6. [PMID: 25727365 DOI: 10.1002/jcb.25124] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 02/02/2015] [Indexed: 12/11/2022]
Abstract
The cell nucleus plays a key role in differentiation processes in eukaryotic cells. It is not the nucleus in particular, but the organization of the genes and their remodeling that provides the data for the adjustments to be made according to the medium. The neutrophil nucleus has a different morphology. It is a multi-lobed nucleus where some researchers argue no longer function. However, studies indicate that it is very probable the occurrence of chromatin remodeling during activation steps. It may be that the human neutrophil nucleus also contributes to the mobility of neutrophils through thin tissue spaces. Questions like these will be discussed in this small review. The topics include morphology of human neutrophil nucleus, maturation process and modifications of the neutrophil nucleus, neutrophil activation and chromatin modifications, causes and consequences of multi-lobulated segmented morphology, and importance of the nucleus in the formation of neutrophil extracellular traps (NETs).
Collapse
Affiliation(s)
- Leonardo Olivieri Carvalho
- Laboratory of Biochemistry and Protein Chemistry (Proteomics Research), University of Brasilia (UNB), Brasília, Brazil
| | - Elaine Nascimento Aquino
- Laboratory of Biochemistry and Protein Chemistry (Proteomics Research), University of Brasilia (UNB), Brasília, Brazil
| | - Anne Caroline Dias Neves
- Laboratory of Biochemistry and Protein Chemistry (Proteomics Research), University of Brasilia (UNB), Brasília, Brazil
| | - Wagner Fontes
- Laboratory of Biochemistry and Protein Chemistry (Proteomics Research), University of Brasilia (UNB), Brasília, Brazil
| |
Collapse
|
20
|
Association of lamin A/C with muscle gene-specific promoters in myoblasts. Biochem Biophys Rep 2015; 4:76-82. [PMID: 29124189 PMCID: PMC5668900 DOI: 10.1016/j.bbrep.2015.08.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 08/10/2015] [Accepted: 08/26/2015] [Indexed: 11/20/2022] Open
Abstract
The A-type and B-type lamins form a filamentous meshwork underneath the inner nuclear membrane called the nuclear lamina, which is an important component of nuclear architecture in metazoan cells. The lamina interacts with large, mostly repressive chromatin domains at the nuclear periphery. In addition, genome–lamina interactions also involve dynamic association of lamin A/C with gene promoters in adipocytes. Mutations in the human lamin A gene cause a spectrum of hereditary diseases called the laminopathies which affect muscle, cardiac and adipose tissues. Since most mutations in lamin A/C affect skeletal muscle, we investigated lamin–chromatin interactions at promoters of muscle specific genes in both muscle and non-muscle cell lines by ChIP-qPCR. We observed that lamin A/C was specifically associated with promoter regions of muscle genes in myoblasts but not in fibroblasts. Lamin A/C dissociated from the promoter regions of the differentiation specific MyoD, myogenin and muscle creatine kinase genes when myoblasts were induced to differentiate. In the promoter regions of the myogenin and MyoD genes, the binding of lamin A/C in myoblasts inversely correlated with the active histone mark, H3K4me3. Lamin A/C binding on muscle genes was reduced and differentiation potential was enhanced on treatment of myoblasts with a histone deacetylase inhibitor. These findings suggest a role for lamina–chromatin interactions in muscle differentiation and have important implications for the pathological mechanisms of striated muscle associated laminopathies. Lamina–chromatin interactions are important for nuclear processes. We show lamin A/C binding to promoters of muscle genes in myoblasts. Lamin A/C binding is reduced upon myoblast differentiation. Lamin A/C binding inversely correlates with active histone marks on muscle genes. Our findings suggest that lamin A/C binding to promoters is cell-type specific.
Collapse
|
21
|
Verma AD, Parnaik VK. Identification of tissue-specific regulatory region in the zebrafish lamin A promoter. Gene 2015; 567:73-80. [PMID: 25921963 DOI: 10.1016/j.gene.2015.04.067] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 03/24/2015] [Accepted: 04/24/2015] [Indexed: 01/24/2023]
Abstract
Lamins are major structural proteins present in the nuclei of metazoan cells and contribute significantly to nuclear organization and function. The expression of different types of lamins is developmentally regulated and lamin A is detectable in most differentiated tissues. Although the proximal promoter of the mammalian lamin A gene has been characterized, the tissue-specific regulatory elements of the gene have not been identified. In this study, we have cloned and functionally characterized a 2.99 kb segment upstream of exon 1 in the zebrafish lamin A gene. This fragment was able to drive GFP expression in several tissues of the developing embryo at 14-72 h post fertilization in stable transgenic lines. Deletion fragments of the 2.99 kb promoter were analyzed by microinjection into zebrafish embryos in transient assays as well as by luciferase reporter assays in cultured cells. A minimal promoter segment of 1.24 kb conferred tissue-specific expression of GFP in the zebrafish embryo as well as in a myoblast cell line. An 86 bp fragment of this 1.24 kb segment was able to activate a heterologous promoter in myoblasts. Mutational analysis revealed the importance of muscle-specific regulatory motifs in the promoter. Our results have important implications for understanding the tissue-specific regulation and functions of the lamin A gene.
Collapse
Affiliation(s)
- Ajay D Verma
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
| | - Veena K Parnaik
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India.
| |
Collapse
|
22
|
Simon DN, Zastrow MS, Wilson KL. Direct actin binding to A- and B-type lamin tails and actin filament bundling by the lamin A tail. Nucleus 2014. [DOI: 10.4161/nucl.11799] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
|
23
|
Brachner A, Foisner R. Lamina-associated polypeptide (LAP)2α and other LEM proteins in cancer biology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 773:143-63. [PMID: 24563347 DOI: 10.1007/978-1-4899-8032-8_7] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The LEM proteins comprise a heterogeneous family of chromatin-associated proteins that share the LEM domain, a structural motif mediating interaction with the DNA associated protein, Barrier-to-Autointegration Factor (BAF). Most of the LEM proteins are integral proteins of the inner nuclear membrane and associate with the nuclear lamina, a structural scaffold of lamin intermediate filament proteins at the nuclear periphery, which is involved in nuclear mechanical functions and (hetero-)chromatin organization. A few LEM proteins, such as Lamina-associated polypeptide (LAP)2α and Ankyrin and LEM domain-containing protein (Ankle)1 lack transmembrane domains and localize throughout the nucleoplasm and cytoplasm, respectively. LAP2α has been reported to regulate cell proliferation by affecting the activity of retinoblastoma protein in tissue progenitor cells and numerous studies showed upregulation of LAP2α in cancer. Ankle1 is a nuclease likely involved in DNA damage repair pathways and single nucleotide polymorphisms in the Ankle1 gene have been linked to increased breast and ovarian cancer risk. In this review we describe potential mechanisms of the involvement of LEM proteins, particularly of LAP2α and Ankle1 in tumorigenesis and we provide evidence that LAP2α expression may be a valuable diagnostic and prognostic marker for tumor analyses.
Collapse
Affiliation(s)
- Andreas Brachner
- Max F. Perutz Laboratories, Medical University Vienna, Dr. Bohr-Gasse 9, 1030, Vienna, Austria,
| | | |
Collapse
|
24
|
|
25
|
Sehgal P, Chaturvedi P, Kumaran RI, Kumar S, Parnaik VK. Lamin A/C haploinsufficiency modulates the differentiation potential of mouse embryonic stem cells. PLoS One 2013; 8:e57891. [PMID: 23451281 PMCID: PMC3581495 DOI: 10.1371/journal.pone.0057891] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 01/28/2013] [Indexed: 02/06/2023] Open
Abstract
Background Lamins are structural proteins that are the major determinants of nuclear architecture and play important roles in various nuclear functions including gene regulation and cell differentiation. Mutations in the human lamin A gene cause a spectrum of genetic diseases that affect specific tissues. Most available mouse models for laminopathies recapitulate disease symptoms for muscle diseases and progerias. However, loss of human lamin A/C also has highly deleterious effects on fetal development. Hence it is important to understand the impact of lamin A/C expression levels on embryonic differentiation pathways. Methodology and Principal Findings We have investigated the differentiation potential of mouse embryonic stem cells containing reduced levels of lamin A/C by detailed lineage analysis of embryoid bodies derived from these cells by in vitro culture. We initially carried out a targeted disruption of one allele of the mouse lamin A/C gene (Lmna). Undifferentiated wild-type and Lmna+/− embryonic stem cells showed similar expression of pluripotency markers and cell cycle profiles. Upon spontaneous differentiation into embryoid bodies, markers for visceral endoderm such as α-fetoprotein were highly upregulated in haploinsufficient cells. However, neuronal markers such as β-III tubulin and nestin were downregulated. Furthermore, we observed a reduction in the commitment of Lmna+/− cells into the myogenic lineage, but no discernible effects on cardiac, adipocyte or osteocyte lineages. In the next series of experiments, we derived embryonic stem cell clones expressing lamin A/C short hairpin RNA and examined their differentiation potential. These cells expressed pluripotency markers and, upon differentiation, the expression of lineage-specific markers was altered as observed with Lmna+/− embryonic stem cells. Conclusions We have observed significant effects on embryonic stem cell differentiation to visceral endoderm, neuronal and myogenic lineages upon depletion of lamin A/C. Hence our results implicate lamin A/C level as an important determinant of lineage-specific differentiation during embryonic development.
Collapse
Affiliation(s)
- Poonam Sehgal
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - R. Ileng Kumaran
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Satish Kumar
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Veena K. Parnaik
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
- * E-mail:
| |
Collapse
|
26
|
Quantification of the Spatial Organization of the Nuclear Lamina as a Tool for Cell Classification. ISRN MOLECULAR BIOLOGY 2013; 2013:374385. [PMID: 27335676 PMCID: PMC4890873 DOI: 10.1155/2013/374385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 10/01/2013] [Indexed: 11/23/2022]
Abstract
The nuclear lamina is the structural scaffold of the nuclear envelope that plays multiple regulatory roles in chromatin organization and gene expression as well as a structural role in nuclear stability. The lamina proteins, also referred to as lamins, determine nuclear lamina organization and define the nuclear shape and the structural integrity of the cell nucleus. In addition, lamins are connected with both nuclear and cytoplasmic structures forming a dynamic cellular structure whose shape changes upon external and internal signals. When bound to the nuclear lamina, the lamins are mobile, have an impact on the nuclear envelop structure, and may induce changes in their regulatory functions. Changes in the nuclear lamina shape cause changes in cellular functions. A quantitative description of these structural changes could provide an unbiased description of changes in cellular function. In this review, we describe how changes in the nuclear lamina can be measured from three-dimensional images of lamins at the nuclear envelope, and we discuss how structural changes of the nuclear lamina can be used for cell classification.
Collapse
|
27
|
Affiliation(s)
- Chin Yee Ho
- Cornell University, Weill Institute for Cell and Molecular Biology, Department of Biomedical Engineering, Ithaca, NY 14853, USA
| | | |
Collapse
|
28
|
Chaturvedi P, Khanna R, Parnaik VK. Ubiquitin ligase RNF123 mediates degradation of heterochromatin protein 1α and β in lamin A/C knock-down cells. PLoS One 2012; 7:e47558. [PMID: 23077635 PMCID: PMC3471868 DOI: 10.1371/journal.pone.0047558] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 09/17/2012] [Indexed: 11/19/2022] Open
Abstract
Background The nuclear lamina is a key determinant of nuclear architecture, integrity and functionality in metazoan nuclei. Mutations in the human lamin A gene lead to highly debilitating genetic diseases termed as laminopathies. Expression of lamin A mutations or reduction in levels of endogenous A-type lamins leads to nuclear defects such as abnormal nuclear morphology and disorganization of heterochromatin. This is accompanied by increased proteasomal degradation of certain nuclear proteins such as emerin, nesprin-1α, retinoblastoma protein and heterochromatin protein 1 (HP1). However, the pathways of proteasomal degradation have not been well characterized. Methodology/Principal Findings To investigate the mechanisms underlying the degradation of HP1 proteins upon lamin misexpression, we analyzed the effects of shRNA-mediated knock-down of lamins A and C in HeLa cells. Cells with reduced levels of expression of lamins A and C exhibited proteasomal degradation of HP1α and HP1β but not HP1γ. Since specific ubiquitin ligases are upregulated in lamin A/C knock-down cells, further studies were carried out with one of these ligases, RNF123, which has a putative HP1-binding motif. Ectopic expression of GFP-tagged RNF123 directly resulted in degradation of HP1α and HP1β. Mutational analysis showed that the canonical HP1-binding pentapeptide motif PXVXL in the N-terminus of RNF123 was required for binding to HP1 proteins and targeting them for degradation. The role of endogenous RNF123 in the degradation of HP1 isoforms was confirmed by RNF123 RNAi experiments. Furthermore, FRAP analysis suggested that HP1β was displaced from chromatin in laminopathic cells. Conclusions/Significance Our data support a role for RNF123 ubiquitin ligase in the degradation of HP1α and HP1β upon lamin A/C knock-down. Hence lamin misexpression can cause degradation of mislocalized proteins involved in key nuclear processes by induction of specific components of the ubiquitin-proteasome system.
Collapse
Affiliation(s)
| | - Richa Khanna
- Centre for Cellular and Molecular Biology (CSIR), Hyderabad, India
| | - Veena K. Parnaik
- Centre for Cellular and Molecular Biology (CSIR), Hyderabad, India
- * E-mail:
| |
Collapse
|
29
|
Mall M, Walter T, Gorjánácz M, Davidson IF, Nga Ly-Hartig TB, Ellenberg J, Mattaj IW. Mitotic lamin disassembly is triggered by lipid-mediated signaling. J Cell Biol 2012; 198:981-90. [PMID: 22986494 PMCID: PMC3444782 DOI: 10.1083/jcb.201205103] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 08/20/2012] [Indexed: 11/22/2022] Open
Abstract
Disassembly of the nuclear lamina is a key step during open mitosis in higher eukaryotes. The activity of several kinases, including CDK1 (cyclin-dependent kinase 1) and protein kinase C (PKC), has been shown to trigger mitotic lamin disassembly, yet their precise contributions are unclear. In this study, we develop a quantitative imaging assay to study mitotic lamin B1 disassembly in living cells. We find that CDK1 and PKC act in concert to mediate phosphorylation-dependent lamin B1 disassembly during mitosis. Using ribonucleic acid interference (RNAi), we showed that diacylglycerol (DAG)-dependent PKCs triggered rate-limiting steps of lamin disassembly. RNAi-mediated depletion or chemical inhibition of lipins, enzymes that produce DAG, delayed lamin disassembly to a similar extent as does PKC inhibition/depletion. Furthermore, the delay of lamin B1 disassembly after lipin depletion could be rescued by the addition of DAG. These findings suggest that lipins activate a PKC-dependent pathway during mitotic lamin disassembly and provide evidence for a lipid-mediated mitotic signaling event.
Collapse
Affiliation(s)
- Moritz Mall
- European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | | | | | | | | | | | | |
Collapse
|
30
|
Steinberg G, Schuster M, Theisen U, Kilaru S, Forge A, Martin-Urdiroz M. Motor-driven motility of fungal nuclear pores organizes chromosomes and fosters nucleocytoplasmic transport. ACTA ACUST UNITED AC 2012; 198:343-55. [PMID: 22851316 PMCID: PMC3413351 DOI: 10.1083/jcb.201201087] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Exchange between the nucleus and the cytoplasm is controlled by nuclear pore complexes (NPCs). In animals, NPCs are anchored by the nuclear lamina, which ensures their even distribution and proper organization of chromosomes. Fungi do not possess a lamina and how they arrange their chromosomes and NPCs is unknown. Here, we show that motor-driven motility of NPCs organizes the fungal nucleus. In Ustilago maydis, Aspergillus nidulans, and Saccharomyces cerevisiae fluorescently labeled NPCs showed ATP-dependent movements at ~1.0 µm/s. In S. cerevisiae and U. maydis, NPC motility prevented NPCs from clustering. In budding yeast, NPC motility required F-actin, whereas in U. maydis, microtubules, kinesin-1, and dynein drove pore movements. In the latter, pore clustering resulted in chromatin organization defects and led to a significant reduction in both import and export of GFP reporter proteins. This suggests that fungi constantly rearrange their NPCs and corresponding chromosomes to ensure efficient nuclear transport and thereby overcome the need for a structural lamina.
Collapse
Affiliation(s)
- Gero Steinberg
- School of Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
| | | | | | | | | | | |
Collapse
|
31
|
Gurung R, Parnaik VK. Cyclin D3 promotes myogenic differentiation and Pax7 transcription. J Cell Biochem 2012; 113:209-19. [PMID: 21898542 DOI: 10.1002/jcb.23346] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Differentiation of skeletal muscle myoblasts involves activation of muscle-specific markers such as MyoD, Myf5, MRF4, and myogenin, followed by exit from the cell cycle, expression of structural proteins, and fusion into multinucleated myotubes. Cyclin D3 is upregulated during muscle differentiation, and expression of cyclin D3 in proliferating myoblasts causes early activation of myogenesis. In this study, we have identified the genes activated by cyclin D3 expression in C2C12 myoblasts and differentiated cells by real-time PCR analysis. Cyclin D3 expression induced faster differentiation kinetics and increase in levels of myogenic genes such as MyoD, Myf5, and myogenin at an early stage during the differentiation process, although long-term myogenic differentiation was not affected. Transcript levels of the transcription factor Pax7 that is expressed in muscle progenitors were enhanced by cyclin D3 expression in myoblasts. Components of a histone methyltransferase complex recruited by Pax7 to myogenic gene promoters were also regulated by cyclin D3. Further, the Pax7 promoter was upregulated in myoblasts expressing cyclin D3. Myoblasts that expressed cyclin D3 showed moderately higher levels of the cyclin-dependent kinase inhibitor p21 and were stalled in G2/M phase of the cell cycle. Our findings suggest that cyclin D3 primes myoblasts for differentiation by enhancing muscle specific gene expression and cell cycle exit.
Collapse
Affiliation(s)
- Ritika Gurung
- Centre for Cellular and Molecular Biology, Hyderabad, India
| | | |
Collapse
|
32
|
Méndez-López I. [Laminopathies. Nuclear lamina diseases]. Med Clin (Barc) 2012; 138:208-14. [PMID: 21632068 DOI: 10.1016/j.medcli.2011.03.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2011] [Revised: 03/30/2011] [Accepted: 03/31/2011] [Indexed: 02/01/2023]
Abstract
Laminopathies are a group of diseases that share wrong codification of lamins, building proteins of the nuclear lamina. Different tissues are affected in those disorders: striated muscle, adipose tissue, central or peripheral nervous system and aging process. Emery-Dreifuss muscular dystrophy and Hutchinson-Gildford Progery Syndrome are two examples of laminopathies. Other diseases, due to mutations in different genes, impair lamins function by a direct or an indirect way and they are frequently considered together. The last decade has seen an increasing interest and scientific advances on laminopathies that will allow us to answer key questions regarding metabolism, insulin resistance, sudden death and aging. Laminopathies are reviewed in this article from a molecular, pathogenic and clinical point of view.
Collapse
Affiliation(s)
- Iván Méndez-López
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| |
Collapse
|
33
|
Lamin misexpression upregulates three distinct ubiquitin ligase systems that degrade ATR kinase in HeLa cells. Mol Cell Biochem 2012; 365:323-32. [PMID: 22382637 DOI: 10.1007/s11010-012-1272-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 02/16/2012] [Indexed: 12/27/2022]
Abstract
Lamins are the major structural components of the nucleus and mutations in the human lamin A gene cause a number of genetic diseases collectively termed laminopathies. At the cellular level, lamin A mutations cause aberrant nuclear morphology and defects in nuclear functions such as the response to DNA damage. We have investigated the mechanism of depletion of a key damage sensor, ATR (Ataxia-telangiectasia-mutated-and-Rad3-related) kinase, in HeLa cells expressing lamin A mutants or lamin A shRNA. The degradation of ATR kinase in these cells was through the proteasomal pathway as it was reversed by the proteasomal inhibitor MG132. Expression of lamin A mutants or shRNA led to transcriptional activation of three ubiquitin ligase components, namely, RNF123 (ring finger protein 123), HECW2 (HECT domain ligase W2) and the F-box protein FBXW10. Ectopic expression of RNF123, HECW2 or FBXW10 directly resulted in proteasomal degradation of ATR kinase and the ring domain of RNF123 was required for this degradation. However, these ligases did not alter the stability of DNA-dependent protein kinase, which is not depleted upon lamin misexpression. Although degradation of ATR kinase was reversed by MG132, it was not affected by the nuclear export inhibitor, leptomycin B, suggesting that ATR kinase is degraded within the nucleus. Our findings indicate that lamin misexpression can lead to deleterious effects on the stability of the key DNA damage sensor, ATR kinase by upregulation of specific components of the ubiquitination pathway.
Collapse
|
34
|
Kong L, Schäfer G, Bu H, Zhang Y, Zhang Y, Klocker H. Lamin A/C protein is overexpressed in tissue-invading prostate cancer and promotes prostate cancer cell growth, migration and invasion through the PI3K/AKT/PTEN pathway. Carcinogenesis 2012; 33:751-9. [PMID: 22301279 DOI: 10.1093/carcin/bgs022] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Prostate cancer (PC) remains the second most common cause of cancer-related death in Western countries. A previous proteomics study suggested that the nuclear membrane protein lamin A/C to be a maker to discriminate low- and high-Gleason score tumors and to identify high-risk cancers. To characterize its function in PC cells, we performed a detailed expression analysis in PC tissue and explored the consequences of down or upregulation of lamin A/C in PC cells. Our results confirm an increased lamin A/C protein expression in high-risk cancers and show association of expression with tumor cell formations at the invasion fronts of tumors and in invasion 'spearheading' tumor cell clusters. In the prostate tumor cell lines, LNCaP, DU145, and PC3 small hairpin RNA knockdown or overexpression of lamin A/C resulted in inhibition or stimulation, respectively, of cell growth, colony formation, migration and invasion. Further mechanism studies suggested that the lamin A/C-related malignant behavior is regulated through modulation of the phosphoinositide 3-kinase (PI3K)/AKT/PTEN signaling pathway. Western blot results indicated that knockdown or overexpression of lamin A/C decreased or increased, respectively, protein levels of the PI3K subunits p110 and p85 in all three cell lines; phosphor-AKT in the PTEN-negative cell lines LNCaP and PC3, and, increased or decreased, respectively, PTEN protein levels in PTEN-positive DU145 cells. Together, our data suggest that lamin A/C proteins are positively involved in malignant behavior of PC cells through the PI3K/AKT/PTEN pathway. Lamin A/C may represent a new oncogenic factor and a novel therapeutic target for PC.
Collapse
Affiliation(s)
- Lu Kong
- Department of Biochemistry and Molecular Biology, Capital Medical University, No 10 Xitoutiao, You An Men, Beijing 100069, PR China
| | | | | | | | | | | |
Collapse
|
35
|
Wendl J, Ebach K, Rodler D, Kenngott RAM. Immunocytochemical localization of cytoplasmic and nuclear intermediate filaments in the bovine ovary during folliculogenesis. Anat Histol Embryol 2012; 41:190-201. [PMID: 22250786 DOI: 10.1111/j.1439-0264.2011.01123.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2010] [Accepted: 11/01/2011] [Indexed: 11/30/2022]
Abstract
The cellular cytoskeleton is composed of three fibrillar systems, namely actin microfilaments, microtubules and intermediate filaments (IFs). It not only is a structural system, which mediates functional compartmentalization, but also contributes to many cellular processes such as transport, mitosis, secretion, formation of cell extensions, intercellular communication and apoptosis. In this study, we have examined the distribution of four groups of IFs [cytokeratins (CKs), vimentin, desmin and lamins] in the somatic and germinal cells of the bovine ovary using RT-PCR and immunohistochemical techniques. Using RT-PCR, specific transcripts for all intermediate proteins studied (CK8, CK18, desmin, vimentin, lamin A/C and lamin B1) were detected. A characteristic immunohistochemical staining pattern was observed for the different IFs within the ovary. In this study, we used antibodies against type I CK (acidic CKs: CK14, CK18 and CK19) and type II CK (basic CKs: CK5 and CK8). Among these, only antibodies against CK18 gave a characteristic pattern of immunostaining in the ovary, which included the surface epithelium, the follicle cells, the endothelium of blood vessels and rete ovarii. Antibodies against all other CKs resulted in a weak staining of a limited number of cellular structures (CK5 and CK19) or were completely negative (CK8 and CK14, apart from the surface epithelium). Vimentin antibodies resulted occasionally in a weak staining of the granulosa cells of primary and secondary follicles. In late secondary follicles, the basal and the most apical follicle cells contacting the zona pellucida usually showed a marked immunostaining for vimentin. In antral follicles, three different immunostaining patterns for vimentin were observed. Desmin immunostaining was confined to the smooth muscle cells of blood vessels. Although mRNA for lamin A/C and lamin B1 could be demonstrated using RT-PCR, no immunostaining was found for lamins, neither in the follicle cells nor in the oocytes.
Collapse
Affiliation(s)
- J Wendl
- Lehrstuhl für Anatomie, Histologie und Embryologie, Department of Veterinary Sciences, LMU München, Munich, Germany
| | | | | | | |
Collapse
|
36
|
Nakashima AS, Hussain Butt R, Dyck RH. Alterations in protein and gene expression within the barrel cortices of ZnT3 knockout mice: Experience-independent and dependent changes. Neurochem Int 2011; 59:860-70. [DOI: 10.1016/j.neuint.2011.08.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Revised: 07/27/2011] [Accepted: 08/08/2011] [Indexed: 12/12/2022]
|
37
|
Lamins, laminopathies and disease mechanisms: Possible role for proteasomal degradation of key regulatory proteins. J Biosci 2011; 36:471-9. [DOI: 10.1007/s12038-011-9085-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
38
|
Mewborn SK, Puckelwartz MJ, Abuisneineh F, Fahrenbach JP, Zhang Y, MacLeod H, Dellefave L, Pytel P, Selig S, Labno CM, Reddy K, Singh H, McNally E. Altered chromosomal positioning, compaction, and gene expression with a lamin A/C gene mutation. PLoS One 2010; 5:e14342. [PMID: 21179469 PMCID: PMC3001866 DOI: 10.1371/journal.pone.0014342] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Accepted: 11/23/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Lamins A and C, encoded by the LMNA gene, are filamentous proteins that form the core scaffold of the nuclear lamina. Dominant LMNA gene mutations cause multiple human diseases including cardiac and skeletal myopathies. The nuclear lamina is thought to regulate gene expression by its direct interaction with chromatin. LMNA gene mutations may mediate disease by disrupting normal gene expression. METHODS/FINDINGS To investigate the hypothesis that mutant lamin A/C changes the lamina's ability to interact with chromatin, we studied gene misexpression resulting from the cardiomyopathic LMNA E161K mutation and correlated this with changes in chromosome positioning. We identified clusters of misexpressed genes and examined the nuclear positioning of two such genomic clusters, each harboring genes relevant to striated muscle disease including LMO7 and MBNL2. Both gene clusters were found to be more centrally positioned in LMNA-mutant nuclei. Additionally, these loci were less compacted. In LMNA mutant heart and fibroblasts, we found that chromosome 13 had a disproportionately high fraction of misexpressed genes. Using three-dimensional fluorescence in situ hybridization we found that the entire territory of chromosome 13 was displaced towards the center of the nucleus in LMNA mutant fibroblasts. Additional cardiomyopathic LMNA gene mutations were also shown to have abnormal positioning of chromosome 13, although in the opposite direction. CONCLUSIONS These data support a model in which LMNA mutations perturb the intranuclear positioning and compaction of chromosomal domains and provide a mechanism by which gene expression may be altered.
Collapse
Affiliation(s)
- Stephanie K. Mewborn
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Megan J. Puckelwartz
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
- Department of Human Genetics, The University of Chicago, Chicago, Illinois, United States of America
| | - Fida Abuisneineh
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - John P. Fahrenbach
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Yuan Zhang
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Heather MacLeod
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Lisa Dellefave
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Peter Pytel
- Department of Pathology, The University of Chicago, Chicago, Illinois, United States of America
| | - Sara Selig
- Molecular Medicine Laboratory, Rambam Health Care Campus and Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of Technology, Haifa, Israel
| | - Christine M. Labno
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
| | - Karen Reddy
- Howard Hughes Medical Institute and Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Harinder Singh
- Howard Hughes Medical Institute and Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Elizabeth McNally
- Department of Medicine, The University of Chicago, Chicago, Illinois, United States of America
- Department of Human Genetics, The University of Chicago, Chicago, Illinois, United States of America
| |
Collapse
|
39
|
Muscular laminopathies: role of prelamin A in early steps of muscle differentiation. ACTA ACUST UNITED AC 2010; 51:246-56. [PMID: 21035482 DOI: 10.1016/j.advenzreg.2010.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 09/14/2010] [Indexed: 11/23/2022]
Abstract
Lamin A is a nuclear envelope constituent involved in a group of human disorders, collectively referred to as laminopathies, which include Emery-Dreifuss muscular dystrophy. Because increasing evidence suggests a role of lamin A precursor in nuclear functions, we investigated the processing of prelamin A along muscle differentiation. Both protein levels and cellular localization of prelamin A appears to be modulated during C2C12 mouse myoblasts activation. Similar changes also occur in the expression of two lamin A-binding proteins: emerin and LAP2α. Furthermore prelamin A forms a complex with LAP2α in differentiating myoblasts. Prelamin A accumulation in cycling myoblasts by expressing unprocessable mutants affects LAP2α and PCNA amount and increases caveolin 3 mRNA and protein levels, whilst accumulation of prelamin A in differentiated muscle cells following treatment with a farnesyl transferase inhibitor inhibits caveolin 3 expression. These data provide evidence for a critical role of lamin A precursor in the early steps of muscle cell differentiation. In fact the post-translational processing of prelamin A affects caveolin 3 expression and influences the myoblast differentiation process. Thus, altered lamin A processing could affect myoblast differentiation and/or muscle regeneration and might contribute to the myopathic phenotype.
Collapse
|
40
|
Muroi M, Kazami S, Noda K, Kondo H, Takayama H, Kawatani M, Usui T, Osada H. Application of proteomic profiling based on 2D-DIGE for classification of compounds according to the mechanism of action. ACTA ACUST UNITED AC 2010; 17:460-70. [PMID: 20534344 DOI: 10.1016/j.chembiol.2010.03.016] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Revised: 03/27/2010] [Accepted: 03/31/2010] [Indexed: 01/01/2023]
Abstract
The development of new anticancer agents derived from natural resources requires a rapid identification of their molecular mechanism of action. To make this step short, we have initiated the proteomic profiling of HeLa cells treated with anticancer drugs representing a wide spectrum of mechanisms of action using two-dimensional difference gel electrophoresis (2D-DIGE). Unique proteome patterns were observed in HeLa cells treated with the HSP90 inhibitor geldanamycin, and were similar to the patterns induced by radicicol, a structurally different HSP90 inhibitor. On the other hand, etoposide and ICRF-193, compounds claimed to be topoisomerase II inhibitors, showed different proteomic profiles, which reflect their different biological activities as revealed by cell-cycle analysis. Thus far, combined data from 19 compounds have allowed their successful classification by cluster analysis according to the mechanism of action.
Collapse
Affiliation(s)
- Makoto Muroi
- Chemical Library Validation Team, Chemical Biology Core Facility, Chemical Biology Department, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Nuclear imaging in three dimensions: A unique tool in cancer research. Ann Anat 2010; 192:292-301. [DOI: 10.1016/j.aanat.2010.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2010] [Accepted: 07/18/2010] [Indexed: 11/19/2022]
|
42
|
Relationships at the nuclear envelope: lamins and nuclear pore complexes in animals and plants. Biochem Soc Trans 2010; 38:829-31. [PMID: 20491671 DOI: 10.1042/bst0380829] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The nuclear envelope comprises a distinct compartment at the nuclear periphery that provides a platform for communication between the nucleus and cytoplasm. Signal transfer can proceed by multiple means. Primarily, this is by nucleocytoplasmic trafficking facilitated by NPCs (nuclear pore complexes). Recently, it has been indicated that signals can be transmitted from the cytoskeleton to the intranuclear structures via interlinking transmembrane proteins. In animal cells, the nuclear lamina tightly underlies the inner nuclear membrane and thus represents the protein structure located at the furthest boundary of the nucleus. It enables communication between the nucleus and the cytoplasm via its interactions with chromatin-binding proteins, transmembrane and membrane-associated proteins. Of particular interest is the interaction of the nuclear lamina with NPCs. As both structures fulfil essential roles in close proximity at the nuclear periphery, their interactions have a large impact on cellular processes resulting in affects on tissue differentiation and development. The present review concentrates on the structural and functional lamina-NPC relationship in animal cells and its potential implications to plants.
Collapse
|
43
|
Chaturvedi P, Parnaik VK. Lamin A rod domain mutants target heterochromatin protein 1alpha and beta for proteasomal degradation by activation of F-box protein, FBXW10. PLoS One 2010; 5:e10620. [PMID: 20498703 PMCID: PMC2869352 DOI: 10.1371/journal.pone.0010620] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Accepted: 04/20/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Lamins are major structural proteins of the nucleus and contribute to the organization of various nuclear functions. Mutations in the human lamin A gene cause a number of highly degenerative diseases, collectively termed as laminopathies. Cells expressing lamin mutations exhibit abnormal nuclear morphology and altered heterochromatin organization; however, the mechanisms responsible for these defects are not well understood. METHODOLOGY AND PRINCIPAL FINDINGS The lamin A rod domain mutants G232E, Q294P and R386K are either diffusely distributed or form large aggregates in the nucleoplasm, resulting in aberrant nuclear morphology in various cell types. We examined the effects of these lamin mutants on the distribution of heterochromatin protein 1 (HP1) isoforms. HeLa cells expressing these mutants showed a heterogeneous pattern of HP1alpha and beta depletion but without altering HP1gamma levels. Changes in HP1alpha and beta were not observed in cells expressing wild-type lamin A or mutant R482L, which assembled normally at the nuclear rim. Treatment with proteasomal inhibitors led to restoration of levels of HP1 isoforms and also resulted in stable association of lamin mutants with the nuclear periphery, rim localization of the inner nuclear membrane lamin-binding protein emerin and partial improvement of nuclear morphology. A comparison of the stability of HP1 isoforms indicated that HP1alpha and beta displayed increased turnover and higher basal levels of ubiquitination than HP1gamma. Transcript analysis of components of the ubiquitination pathway showed that a specific F-box protein, FBXW10 was induced several-fold in cells expressing lamin mutants. Importantly, ectopic expression of FBXW10 in HeLa cells led to depletion of HP1alpha and beta without alteration of HP1gamma levels. CONCLUSIONS Mislocalized lamins can induce ubiquitin-mediated proteasomal degradation of certain HP1 isoforms by activation of FBXW10, a member of the F-box family of proteins that is involved in E3 ubiquitin ligase activity.
Collapse
Affiliation(s)
| | - Veena K. Parnaik
- Centre for Cellular and Molecular Biology (CSIR), Hyderabad, India
- * E-mail:
| |
Collapse
|
44
|
Iwatsuki H, Suda M. Seven kinds of intermediate filament networks in the cytoplasm of polarized cells: structure and function. Acta Histochem Cytochem 2010; 43:19-31. [PMID: 20514289 PMCID: PMC2875862 DOI: 10.1267/ahc.10009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 03/15/2010] [Indexed: 02/01/2023] Open
Abstract
Intermediate filaments (IFs) are involved in many important physiological functions, such as the distribution of organelles, signal transduction, cell polarity and gene regulation. However, little information exists on the structure of the IF networks performing these functions. We have clarified the existence of seven kinds of IF networks in the cytoplasm of diverse polarized cells: an apex network just under the terminal web, a peripheral network lying just beneath the cell membrane, a granule-associated network surrounding a mass of secretory granules, a Golgi-associated network surrounding the Golgi apparatus, a radial network locating from the perinuclear region to the specific area of the cell membrane, a juxtanuclear network surrounding the nucleus, and an entire cytoplasmic network. In this review, we describe these seven kinds of IF networks and discuss their biological roles.
Collapse
Affiliation(s)
| | - Masumi Suda
- Department of Anatomy, Kawasaki Medical School
| |
Collapse
|
45
|
Kang K, Lee SB, Yoo JH, Nho CW. Flow cytometric fluorescence pulse width analysis of etoposide-induced nuclear enlargement in HCT116 cells. Biotechnol Lett 2010; 32:1045-52. [PMID: 20429026 PMCID: PMC2903698 DOI: 10.1007/s10529-010-0277-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Accepted: 04/13/2010] [Indexed: 02/05/2023]
Abstract
Fluorescence pulse width can provide size information on the fluorescence-emitting particle, such as the nuclei of propidium iodide-stained cells. To analyze nuclear size in the present study, rather than perform the simple doublet discrimination approach usually employed in flow cytometric DNA content analyses, we assessed the pulse width of the propidium iodide fluorescence signal. The anti-cancer drug etoposide is reportedly cytostatic, can induce a strong G2/M arrest, and results in nuclear enlargement. Based on these characteristics, we used etoposide-treated HCT116 cells as our experimental model system. The fluorescence pulse widths (FL2-W) of etoposide-treated (10 μM, 48 h) cells were distributed at higher positions than those of vehicle control, so the peak FL2-W value of etoposide-treated cells appeared at 400 while those of vehicle control cells appeared at 200 and 270. These results were consistent with our microscopic observations. This etoposide-induced increase in FL2-W was more apparent in G2/M phase than other cell cycle phases, suggesting that etoposide-induced nuclear enlargement preferentially occurred in G2/M phase cells rather than in G0/G1 or S phase cells.
Collapse
Affiliation(s)
- Kyungsu Kang
- Natural Products Research Center, Korea Institute of Science and Technology, Gangneung Institute, Gangneung, Gangwon-do 210-340, Republic of Korea
| | | | | | | |
Collapse
|
46
|
Lara-Chacón B, de León MB, Leocadio D, Gómez P, Fuentes-Mera L, Martínez-Vieyra I, Ortega A, Jans DA, Cisneros B. Characterization of an Importin α/β-recognized nuclear localization signal in β-dystroglycan. J Cell Biochem 2010; 110:706-17. [DOI: 10.1002/jcb.22581] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
47
|
Gurudatta BV, Shashidhara LS, Parnaik VK. Lamin C and chromatin organization in Drosophila. J Genet 2010; 89:37-49. [DOI: 10.1007/s12041-010-0009-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
48
|
Abstract
Dilated cardiomyopathy is characterised by left ventricular dilation that is associated with systolic dysfunction. Diastolic dysfunction and impaired right ventricular function can develop. Affected individuals are at risk of left or right ventricular failure, or both. Heart failure symptoms can be exercise-induced or persistent at rest. Many patients are asymptomatic. Chronically treated patients sometimes present acutely with decompensated heart failure. Other life-threatening risks are ventricular arrhythmias and atrioventricular block, syncope, and sudden death. Genetic inheritance arises in 30-48% of patients, and inflammatory disorders such as myocarditis or toxic effects from medications, alcohol, or illicit drugs also result in dilated cardiomyopathy. Genes that cause dilated cardiomyopathy generally encode cytoskeletal and sarcomeric (contractile apparatus) proteins, although disturbance of calcium homeostasis also seems to be important. In children, disrupted mitochondrial function and metabolic abnormalities have a causal role. Treatments focus on improvement of cardiac efficiency and reduction of mechanical stress. Arrhythmia therapy and prevention of sudden death continue to be mainstays of treatment. Despite progress over the past 10 years, outcomes need to be improved.
Collapse
Affiliation(s)
- John Lynn Jefferies
- Pediatric Cardiology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | | |
Collapse
|
49
|
Andrés V, González JM. Role of A-type lamins in signaling, transcription, and chromatin organization. ACTA ACUST UNITED AC 2010; 187:945-57. [PMID: 20038676 PMCID: PMC2806284 DOI: 10.1083/jcb.200904124] [Citation(s) in RCA: 214] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A-type lamins (lamins A and C), encoded by the LMNA gene, are major protein constituents of the mammalian nuclear lamina, a complex structure that acts as a scaffold for protein complexes that regulate nuclear structure and functions. Interest in these proteins has increased in recent years with the discovery that LMNA mutations cause a variety of human diseases termed laminopathies, including progeroid syndromes and disorders that primarily affect striated muscle, adipose, bone, and neuronal tissues. In this review, we discuss recent research supporting the concept that lamin A/C and associated nuclear envelope proteins regulate gene expression in health and disease through interplay with signal transduction pathways, transcription factors, and chromatin-associated proteins.
Collapse
Affiliation(s)
- Vicente Andrés
- Department of Atherothrombosis and Cardiovascular Imaging, Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain.
| | | |
Collapse
|
50
|
Cortés R, Roselló-Lletí E, Rivera M, Martínez-Dolz L, Azorín I, Salvador A, Portolés M. The role of the nuclear lamins in the pathogenesis of heart failure in patients undergoing cardiac transplantation. Transplant Proc 2010; 41:2227-30. [PMID: 19715882 DOI: 10.1016/j.transproceed.2009.06.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The nuclear lamins A/C play a critical role in maintaining the structure of the nuclear lamina and the organization of various proteins, such as emerin. These protein levels may play roles in the pathogenesis and clinical evolution of both ischemic (ICM) and dilated (DCM) cardiomyopathy. We evaluated the nuclear morphology of cardiomyocytes and determine lamins A/C and emerin levels among DCM and ICM heart failure patients compared with control human hearts. We determined protein levels by Western blots using mouse monoclonal antibodies in 23 explanted human hearts. Lamin A was increased in failing hearts but significantly different only among the DCM compared with the control group: mean, 236 +/- 51 vs 100 +/- 34; (P < .05). However, lamin C in the DCM group was near control values and significantly decreased in the ICM cohort compared to controls 75 +/- 7 versus 100 +/- 3 (P < .05). No alterations in emerin levels were observed in ICM or DCM, compared with controls. In conclusion, hearts with ICM or DCM showed different alterations in the nuclear morphology of cardiomyocytes; ICM patients had decreased lamin C, whereas DCM patients had increased lamin A. These changes affecting nuclear structure and function may have prognostic implications, for cardiomyopathy etiology.
Collapse
Affiliation(s)
- R Cortés
- Unidad de Cardiocirculación, Centro de Investigación, Hospital Universitario La Fe, Valencia, Spain
| | | | | | | | | | | | | |
Collapse
|