1
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D’Apice MR, De Dominicis A, Murdocca M, Amati F, Botta A, Sangiuolo F, Lattanzi G, Federici M, Novelli G. Cutaneous and metabolic defects associated with nuclear abnormalities in a transgenic mouse model expressing R527H lamin A mutation causing mandibuloacral dysplasia type A (MADA) syndrome. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2020; 39:320-335. [PMID: 33458588 PMCID: PMC7783430 DOI: 10.36185/2532-1900-036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 11/11/2020] [Indexed: 06/12/2023]
Abstract
LMNA gene encodes for lamin A/C, attractive proteins linked to nuclear structure and functions. When mutated, it causes different rare diseases called laminopathies. In particular, an Arginine change in Histidine in position 527 (p.Arg527His) falling in the C-terminal domain of lamin A precursor form (prelamin A) causes mandibuloacral dysplasia Type A (MADA), a segmental progeroid syndrome characterized by skin, bone and metabolic anomalies. The well-characterized cellular models made difficult to assess the tissue-specific functions of 527His prelamin A. Here, we describe the generation and characterization of a MADA transgenic mouse overexpressing 527His LMNA gene, encoding mutated prelamin A. Bodyweight is slightly affected, while no difference in lifespan was observed in transgenic animals. Mild metabolic anomalies and thinning and loss of hairs from the back were the other observed phenotypic MADA manifestations. Histological analysis of tissues relevant for MADA syndrome revealed slight increase in adipose tissue inflammatory cells and a reduction of hypodermis due to a loss of subcutaneous adipose tissue. At cellular levels, transgenic cutaneous fibroblasts displayed nuclear envelope aberrations, presence of prelamin A, proliferation, and senescence rate defects. Gene transcriptional pattern was found differentially modulated between transgenic and wildtype animals, too. In conclusion, the presence of 527His Prelamin A accumulation is further linked to the appearance of mild progeroid features and metabolic disorder without lifespan reduction.
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Affiliation(s)
| | | | - Michela Murdocca
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Francesca Amati
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Annalisa Botta
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Federica Sangiuolo
- Laboratory of Medical Genetics, Tor Vergata Hospital, Rome, Italy
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Giovanna Lattanzi
- Center for Atherosclerosis, School of Medicine, University of Rome ‘Tor Vergata’, Rome, Italy
| | - Massimo Federici
- Center for Atherosclerosis, School of Medicine, University of Rome ‘Tor Vergata’, Rome, Italy
| | - Giuseppe Novelli
- Laboratory of Medical Genetics, Tor Vergata Hospital, Rome, Italy
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
- Neuromed IRCCS Institute, Pozzilli (IS), Italy
- School of Medicine, University of Nevada, Reno, NV, USA
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2
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D'Apice MR, De Dominicis A, Murdocca M, Amati F, Botta A, Sangiuolo F, Lattanzi G, Federici M, Novelli G. Cutaneous and metabolic defects associated with nuclear abnormalities in a transgenic mouse model expressing R527H lamin A mutation causing mandibuloacral dysplasia type A (MADA) syndrome. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2020; 39. [PMID: 33458588 PMCID: PMC7783430 DOI: 10.36185/2532-1900-036&set/a 907644967+854571971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
LMNA gene encodes for lamin A/C, attractive proteins linked to nuclear structure and functions. When mutated, it causes different rare diseases called laminopathies. In particular, an Arginine change in Histidine in position 527 (p.Arg527His) falling in the C-terminal domain of lamin A precursor form (prelamin A) causes mandibuloacral dysplasia Type A (MADA), a segmental progeroid syndrome characterized by skin, bone and metabolic anomalies. The well-characterized cellular models made difficult to assess the tissue-specific functions of 527His prelamin A. Here, we describe the generation and characterization of a MADA transgenic mouse overexpressing 527His LMNA gene, encoding mutated prelamin A. Bodyweight is slightly affected, while no difference in lifespan was observed in transgenic animals. Mild metabolic anomalies and thinning and loss of hairs from the back were the other observed phenotypic MADA manifestations. Histological analysis of tissues relevant for MADA syndrome revealed slight increase in adipose tissue inflammatory cells and a reduction of hypodermis due to a loss of subcutaneous adipose tissue. At cellular levels, transgenic cutaneous fibroblasts displayed nuclear envelope aberrations, presence of prelamin A, proliferation, and senescence rate defects. Gene transcriptional pattern was found differentially modulated between transgenic and wildtype animals, too. In conclusion, the presence of 527His Prelamin A accumulation is further linked to the appearance of mild progeroid features and metabolic disorder without lifespan reduction.
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Affiliation(s)
| | | | - Michela Murdocca
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Francesca Amati
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Annalisa Botta
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Federica Sangiuolo
- Laboratory of Medical Genetics, Tor Vergata Hospital, Rome, Italy.,Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy
| | - Giovanna Lattanzi
- Center for Atherosclerosis, School of Medicine, University of Rome 'Tor Vergata', Rome, Italy
| | - Massimo Federici
- Center for Atherosclerosis, School of Medicine, University of Rome 'Tor Vergata', Rome, Italy
| | - Giuseppe Novelli
- Laboratory of Medical Genetics, Tor Vergata Hospital, Rome, Italy.,Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy.,Neuromed IRCCS Institute, Pozzilli (IS), Italy.,School of Medicine, University of Nevada, Reno, NV, USA
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3
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Cenni V, Capanni C, Mattioli E, Schena E, Squarzoni S, Bacalini MG, Garagnani P, Salvioli S, Franceschi C, Lattanzi G. Lamin A involvement in ageing processes. Ageing Res Rev 2020; 62:101073. [PMID: 32446955 DOI: 10.1016/j.arr.2020.101073] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 03/05/2020] [Accepted: 04/11/2020] [Indexed: 12/29/2022]
Abstract
Lamin A, a main constituent of the nuclear lamina, is the major splicing product of the LMNA gene, which also encodes lamin C, lamin A delta 10 and lamin C2. Involvement of lamin A in the ageing process became clear after the discovery that a group of progeroid syndromes, currently referred to as progeroid laminopathies, are caused by mutations in LMNA gene. Progeroid laminopathies include Hutchinson-Gilford Progeria, Mandibuloacral Dysplasia, Atypical Progeria and atypical-Werner syndrome, disabling and life-threatening diseases with accelerated ageing, bone resorption, lipodystrophy, skin abnormalities and cardiovascular disorders. Defects in lamin A post-translational maturation occur in progeroid syndromes and accumulated prelamin A affects ageing-related processes, such as mTOR signaling, epigenetic modifications, stress response, inflammation, microRNA activation and mechanosignaling. In this review, we briefly describe the role of these pathways in physiological ageing and go in deep into lamin A-dependent mechanisms that accelerate the ageing process. Finally, we propose that lamin A acts as a sensor of cell intrinsic and environmental stress through transient prelamin A accumulation, which triggers stress response mechanisms. Exacerbation of lamin A sensor activity due to stably elevated prelamin A levels contributes to the onset of a permanent stress response condition, which triggers accelerated ageing.
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Affiliation(s)
- Vittoria Cenni
- CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", Unit of Bologna, Bologna, Italy; IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Cristina Capanni
- CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", Unit of Bologna, Bologna, Italy; IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Elisabetta Mattioli
- CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", Unit of Bologna, Bologna, Italy; IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Elisa Schena
- CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", Unit of Bologna, Bologna, Italy; IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Stefano Squarzoni
- CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", Unit of Bologna, Bologna, Italy; IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | | | - Paolo Garagnani
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy; Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet at Huddinge, University Hospital, Stockholm, Sweden
| | - Stefano Salvioli
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy; Interdepartmental Center Alma Mater Research Institute on Global Challenges and Climate Changes, University of Bologna, Bologna, Italy
| | - Claudio Franceschi
- Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - Giovanna Lattanzi
- CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", Unit of Bologna, Bologna, Italy; IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy.
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4
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Lamin A and Prelamin A Counteract Migration of Osteosarcoma Cells. Cells 2020; 9:cells9030774. [PMID: 32235738 PMCID: PMC7140691 DOI: 10.3390/cells9030774] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 03/16/2020] [Accepted: 03/19/2020] [Indexed: 12/11/2022] Open
Abstract
A type lamins are fundamental components of the nuclear lamina. Changes in lamin A expression correlate with malignant transformation in several cancers. However, the role of lamin A has not been explored in osteosarcoma (OS). Here, we wanted to investigate the role of lamin A in normal osteoblasts (OBs) and OS cells. Thus, we studied the expression of lamin A/C in OS cells compared to OBs and evaluated the effects of lamin A overexpression in OS cell lines. We show that, while lamin A expression increases during osteoblast differentiation, all examined OS cell lines express lower lamin A levels relative to differentiated OBs. The condition of low LMNA expression confers to OS cells a significant increase in migration potential, while overexpression of lamin A reduces migration ability of OS cells. Moreover, overexpression of unprocessable prelamin A also reduces cell migration. In agreement with the latter finding, OS cells which accumulate the highest prelamin A levels upon inhibition of lamin A maturation by statins, had significantly reduced migration ability. Importantly, OS cells subjected to statin treatment underwent apoptotic cell death in a RAS-independent, lamin A-dependent manner. Our results show that pro-apoptotic effects of statins and statin inhibitory effect on OS cell migration are comparable to those obtained by prelamin A accumulation and further suggest that modulation of lamin A expression and post-translational processing can be a tool to decrease migration potential in OS cells.
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5
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Looking at New Unexpected Disease Targets in LMNA-Linked Lipodystrophies in the Light of Complex Cardiovascular Phenotypes: Implications for Clinical Practice. Cells 2020; 9:cells9030765. [PMID: 32245113 PMCID: PMC7140635 DOI: 10.3390/cells9030765] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/01/2020] [Accepted: 03/07/2020] [Indexed: 12/13/2022] Open
Abstract
Variants in LMNA, encoding A-type lamins, are responsible for laminopathies including muscular dystrophies, lipodystrophies, and progeroid syndromes. Cardiovascular laminopathic involvement is classically described as cardiomyopathy in striated muscle laminopathies, and arterial wall dysfunction and/or valvulopathy in lipodystrophic and/or progeroid laminopathies. We report unexpected cardiovascular phenotypes in patients with LMNA-associated lipodystrophies, illustrating the complex multitissular pathophysiology of the disease and the need for specific cardiovascular investigations in affected patients. A 33-year-old woman was diagnosed with generalized lipodystrophy and atypical progeroid syndrome due to the newly identified heterozygous LMNA p.(Asp136Val) variant. Her complex cardiovascular phenotype was associated with atherosclerosis, aortic valvular disease and left ventricular hypertrophy with rhythm and conduction defects. A 29-year-old woman presented with a partial lipodystrophy syndrome and a severe coronary atherosclerosis which required a triple coronary artery bypass grafting. She carried the novel heterozygous p.(Arg60Pro) LMNA variant inherited from her mother, affected with partial lipodystrophy and dilated cardiomyopathy. Different lipodystrophy-associated LMNA pathogenic variants could target cardiac vasculature and/or muscle, leading to complex overlapping phenotypes. Unifying pathophysiological hypotheses should be explored in several cell models including adipocytes, cardiomyocytes and vascular cells. Patients with LMNA-associated lipodystrophy should be systematically investigated with 24-h ECG monitoring, echocardiography and non-invasive coronary function testing.
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6
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Zironi I, Gavoçi E, Lattanzi G, Virelli A, Amorini F, Remondini D, Castellani G. BK channel overexpression on plasma membrane of fibroblasts from Hutchinson-Gilford progeria syndrome. Aging (Albany NY) 2019; 10:3148-3160. [PMID: 30398975 PMCID: PMC6286842 DOI: 10.18632/aging.101621] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 10/27/2018] [Indexed: 12/15/2022]
Abstract
Hutchinson-Gilford progeria syndrome (HGPS) is an extremely rare genetic disorder wherein symptoms resembling aspects of aging are manifested at a very early age. It is a genetic condition that occurs due to a de novo mutation in the LMNA gene encoding for the nuclear structural protein lamin A. The lamin family of proteins are thought to be involved in nuclear stability, chromatin structure and gene expression and this leads to heavy effects on the regulation and functionality of the cell machinery. The functional role of the large-conductance calcium-activated potassium channels (BKCa) is still unclear, but has been recently described a strong relationship with their membrane expression, progerin nuclear levels and the ageing process. In this study, we found that: i) the outward potassium membrane current amplitude and the fluorescence intensity of the BKCa channel probe showed higher values in human dermal fibroblast obtained from patients affected by HGPS if compared to that from healthy young subjects; ii) this result appears to correlate with a basic cellular activity such as the replicative boost. We suggest that studying the HGPS also from the electrophysiological point of view might reveal new clues about the normal process of aging.
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Affiliation(s)
- Isabella Zironi
- Department of Physics and Astronomy (D.I.F.A.) University of Bologna, Bologna, Italy.,Interdepartmental Centre "L. Galvani" for integrated studies of Bioinformatics, Biophysics and Biocomplexity (C.I.G.) University of Bologna, Bologna, Italy.,National Institute for Nuclear Physics (INFN), Bologna, Italy
| | - Entelë Gavoçi
- National Institute for Nuclear Physics (INFN), Bologna, Italy
| | - Giovanna Lattanzi
- CNR Institute of Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopedic Institute, Bologna, Italy
| | - Angela Virelli
- Department of Physics and Astronomy (D.I.F.A.) University of Bologna, Bologna, Italy
| | - Fabrizio Amorini
- Department of Physics and Astronomy (D.I.F.A.) University of Bologna, Bologna, Italy
| | - Daniel Remondini
- Department of Physics and Astronomy (D.I.F.A.) University of Bologna, Bologna, Italy.,Interdepartmental Centre "L. Galvani" for integrated studies of Bioinformatics, Biophysics and Biocomplexity (C.I.G.) University of Bologna, Bologna, Italy.,National Institute for Nuclear Physics (INFN), Bologna, Italy
| | - Gastone Castellani
- Department of Physics and Astronomy (D.I.F.A.) University of Bologna, Bologna, Italy.,Interdepartmental Centre "L. Galvani" for integrated studies of Bioinformatics, Biophysics and Biocomplexity (C.I.G.) University of Bologna, Bologna, Italy.,National Institute for Nuclear Physics (INFN), Bologna, Italy
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7
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Wu J, Guan F, Luo W, Yuan Z, Chen R, Gou X, Shi X, Guo H, Fang K. Retracted
: Prelamin A overexpression promotes detrusor calcification/aging in urinary incontinence via prelamin A accumulation. J Cell Physiol 2019; 234:17800-17811. [DOI: 10.1002/jcp.28406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 12/26/2022]
Affiliation(s)
- Jing Wu
- Department of Biochemistry and Molecular Biology The Primary Medicine School of Kunming Medical University Kunming China
| | - Fei Guan
- Department of Urology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
| | - Wei Luo
- Department of Urology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
| | - Zhi‐Wei Yuan
- Department of Pathology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
| | - Rong‐Qiong Chen
- Department of Urology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
| | - Xin Gou
- Department of Urology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
| | - Xin Shi
- Department of Urology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
| | - Hai‐Xiang Guo
- Department of Urology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
| | - Ke‐Wei Fang
- Department of Urology The Second Affiliated Hospital of Kunming Medical University Kunming P. R. China
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8
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Mattioli E, Andrenacci D, Garofalo C, Prencipe S, Scotlandi K, Remondini D, Gentilini D, Di Blasio AM, Valente S, Scarano E, Cicchilitti L, Piaggio G, Mai A, Lattanzi G. Altered modulation of lamin A/C-HDAC2 interaction and p21 expression during oxidative stress response in HGPS. Aging Cell 2018; 17:e12824. [PMID: 30109767 PMCID: PMC6156291 DOI: 10.1111/acel.12824] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 05/22/2018] [Accepted: 06/26/2018] [Indexed: 02/01/2023] Open
Abstract
Defects in stress response are main determinants of cellular senescence and organism aging. In fibroblasts from patients affected by Hutchinson-Gilford progeria, a severe LMNA-linked syndrome associated with bone resorption, cardiovascular disorders, and premature aging, we found altered modulation of CDKN1A, encoding p21, upon oxidative stress induction, and accumulation of senescence markers during stress recovery. In this context, we unraveled a dynamic interaction of lamin A/C with HDAC2, an histone deacetylase that regulates CDKN1A expression. In control skin fibroblasts, lamin A/C is part of a protein complex including HDAC2 and its histone substrates; protein interaction is reduced at the onset of DNA damage response and recovered after completion of DNA repair. This interplay parallels modulation of p21 expression and global histone acetylation, and it is disrupted by LMNAmutations leading to progeroid phenotypes. In fact, HGPS cells show impaired lamin A/C-HDAC2 interplay and accumulation of p21 upon stress recovery. Collectively, these results link altered physical interaction between lamin A/C and HDAC2 to cellular and organism aging. The lamin A/C-HDAC2 complex may be a novel therapeutic target to slow down progression of progeria symptoms.
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Affiliation(s)
- Elisabetta Mattioli
- CNR Institute of Molecular Genetics, Unit of Bologna; Bologna Italy
- Rizzoli Orthopedic Institute; IRCCS; Bologna Italy
| | - Davide Andrenacci
- CNR Institute of Molecular Genetics, Unit of Bologna; Bologna Italy
- Rizzoli Orthopedic Institute; IRCCS; Bologna Italy
| | - Cecilia Garofalo
- Rizzoli Orthopedic Institute; IRCCS; Bologna Italy
- CRS Development of Biomolecular Therapies, Experimental Oncology Lab; Rizzoli Institute; Bologna Italy
| | - Sabino Prencipe
- CNR Institute of Molecular Genetics, Unit of Bologna; Bologna Italy
- Rizzoli Orthopedic Institute; IRCCS; Bologna Italy
| | - Katia Scotlandi
- Rizzoli Orthopedic Institute; IRCCS; Bologna Italy
- CRS Development of Biomolecular Therapies, Experimental Oncology Lab; Rizzoli Institute; Bologna Italy
| | - Daniel Remondini
- Department of Physics and Astronomy; University of Bologna; Bologna Italy
| | - Davide Gentilini
- Centre for Biomedical Research and Technologies; Italian Auxologic Institute, IRCCS; Milan Italy
| | - Anna Maria Di Blasio
- Centre for Biomedical Research and Technologies; Italian Auxologic Institute, IRCCS; Milan Italy
| | - Sergio Valente
- Department of Drug Chemistry and Technologies; Pasteur Institute Italy; Cenci-Bolognetti Foundation; Sapienza University of Rome; Rome Italy
| | - Emanuela Scarano
- Pediatric Endocrinology and Rare Diseases Unit; University of Bologna; Bologna Italy
| | - Lucia Cicchilitti
- UOSD SAFU, Department of Research, Diagnosis and Innovative Technologies; IRCCS - Regina Elena National Cancer Institute; Rome Italy
| | - Giulia Piaggio
- UOSD SAFU, Department of Research, Diagnosis and Innovative Technologies; IRCCS - Regina Elena National Cancer Institute; Rome Italy
| | - Antonello Mai
- Department of Drug Chemistry and Technologies; Pasteur Institute Italy; Cenci-Bolognetti Foundation; Sapienza University of Rome; Rome Italy
| | - Giovanna Lattanzi
- CNR Institute of Molecular Genetics, Unit of Bologna; Bologna Italy
- Rizzoli Orthopedic Institute; IRCCS; Bologna Italy
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9
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Gargiuli C, Schena E, Mattioli E, Columbaro M, D'Apice MR, Novelli G, Greggi T, Lattanzi G. Lamins and bone disorders: current understanding and perspectives. Oncotarget 2018; 9:22817-22831. [PMID: 29854317 PMCID: PMC5978267 DOI: 10.18632/oncotarget.25071] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 03/22/2018] [Indexed: 12/31/2022] Open
Abstract
Lamin A/C is a major constituent of the nuclear lamina implicated in a number of genetic diseases, collectively known as laminopathies. The most severe forms of laminopathies feature, among other symptoms, congenital scoliosis, osteoporosis, osteolysis or delayed cranial ossification. Importantly, specific bone districts are typically affected in laminopathies. Spine is severely affected in LMNA-linked congenital muscular dystrophy. Mandible, terminal phalanges and clavicles undergo osteolytic processes in progeroid laminopathies and Restrictive Dermopathy, a lethal developmental laminopathy. This specificity suggests that lamin A/C regulates fine mechanisms of bone turnover, as supported by data showing that lamin A/C mutations activate non-canonical pathways of osteoclastogenesis, as the one dependent on TGF beta 2. Here, we review current knowledge on laminopathies affecting bone and LMNA involvement in bone turnover and highlight lamin-dependent mechanisms causing bone disorders. This knowledge can be exploited to identify new therapeutic approaches not only for laminopathies, but also for other rare diseases featuring bone abnormalities.
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Affiliation(s)
- Chiara Gargiuli
- CNR Institute of Molecular Genetics, Unit of Bologna, Bologna, Italy
| | - Elisa Schena
- CNR Institute of Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopaedic Institute, Laboratory of Cell Biology, Bologna, Italy
| | - Elisabetta Mattioli
- CNR Institute of Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopaedic Institute, Laboratory of Cell Biology, Bologna, Italy
| | - Marta Columbaro
- Rizzoli Orthopaedic Institute, Laboratory of Cell Biology, Bologna, Italy
| | | | - Giuseppe Novelli
- Medical Genetics Unit, Policlinico Tor Vergata University Hospital, Rome, Italy
| | - Tiziana Greggi
- Rizzoli Orthopaedic Institute, Spine Deformity Department, Bologna, Italy
| | - Giovanna Lattanzi
- CNR Institute of Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopaedic Institute, Laboratory of Cell Biology, Bologna, Italy
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10
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Mandibuloacral dysplasia: A premature ageing disease with aspects of physiological ageing. Ageing Res Rev 2018; 42:1-13. [PMID: 29208544 DOI: 10.1016/j.arr.2017.12.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/09/2017] [Accepted: 12/01/2017] [Indexed: 01/12/2023]
Abstract
Mandibuloacral dysplasia (MAD) is a rare genetic condition characterized by bone abnormalities including localized osteolysis and generalized osteoporosis, skin pigmentation, lipodystrophic signs and mildly accelerated ageing. The molecular defects associated with MAD are mutations in LMNA or ZMPSTE24 (FACE1) gene, causing type A or type B MAD, respectively. Downstream of LMNA or ZMPSTE24 mutations, the lamin A precursor, prelamin A, is accumulated in cells and affects chromatin dynamics and stress response. A new form of mandibuloacral dysplasia has been recently associated with mutations in POLD1 gene, encoding DNA polymerase delta, a major player in DNA replication. Of note, involvement of prelamin A in chromatin dynamics and recruitment of DNA repair factors has been also determined under physiological conditions, at the border between stress response and cellular senescence. Here, we review current knowledge on MAD clinical and pathogenetic aspects and highlight aspects typical of physiological ageing.
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11
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Abstract
Lamins are major components of the nuclear lamina, a network of proteins that supports the nuclear envelope in metazoan cells. Over the past decade, biochemical studies have provided support for the view that lamins are not passive bystanders providing mechanical stability to the nucleus but play an active role in the organization of the genome and the function of fundamental nuclear processes. It has also become apparent that lamins are critical for human health, as a large number of mutations identified in the gene that encodes for A-type lamins are associated with tissue-specific and systemic genetic diseases, including the accelerated aging disorder known as Hutchinson-Gilford progeria syndrome. Recent years have witnessed great advances in our understanding of the role of lamins in the nucleus and the functional consequences of disease-associated A-type lamin mutations. Many of these findings have been presented in comprehensive reviews. In this mini-review, we discuss recent breakthroughs in the role of lamins in health and disease and what lies ahead in lamin research.
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Affiliation(s)
- Sita Reddy
- Department of Biochemistry and Molecular Biology, Institute for Genetic Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Lucio Comai
- Department of Biochemistry and Molecular Biology, Institute for Genetic Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA; Department of Molecular Microbiology and Immunology, Institute for Genetic Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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12
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All-trans retinoic acid and rapamycin normalize Hutchinson Gilford progeria fibroblast phenotype. Oncotarget 2016; 6:29914-28. [PMID: 26359359 PMCID: PMC4745772 DOI: 10.18632/oncotarget.4939] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 07/31/2015] [Indexed: 11/25/2022] Open
Abstract
Hutchinson Gilford progeria syndrome is a fatal disorder characterized by accelerated aging, bone resorption and atherosclerosis, caused by a LMNA mutation which produces progerin, a mutant lamin A precursor. Progeria cells display progerin and prelamin A nuclear accumulation, altered histone methylation pattern, heterochromatin loss, increased DNA damage and cell cycle alterations. Since the LMNA promoter contains a retinoic acid responsive element, we investigated if all-trans retinoic acid administration could lower progerin levels in cultured fibroblasts. We also evaluated the effect of associating rapamycin, which induces autophagic degradation of progerin and prelamin A. We demonstrate that all-trans retinoic acid acts synergistically with low-dosage rapamycin reducing progerin and prelamin A, via transcriptional downregulation associated with protein degradation, and increasing the lamin A to progerin ratio. These effects rescue cell dynamics and cellular proliferation through recovery of DNA damage response factor PARP1 and chromatin-associated nuclear envelope proteins LAP2α and BAF. The combined all-trans retinoic acid-rapamycin treatment is dramatically efficient, highly reproducible, represents a promising new approach in Hutchinson-Gilford Progeria therapy and deserves investigation in ageing-associated disorders.
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Evangelisti C, Cenni V, Lattanzi G. Potential therapeutic effects of the MTOR inhibitors for preventing ageing and progeria-related disorders. Br J Clin Pharmacol 2016; 82:1229-1244. [PMID: 26952863 PMCID: PMC5061804 DOI: 10.1111/bcp.12928] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 03/02/2016] [Accepted: 03/02/2016] [Indexed: 12/25/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) pathway is an highly conserved signal transduction axis involved in many cellular processes, such as cell growth, survival, transcription, translation, apoptosis, metabolism, motility and autophagy. Recently, this signalling pathway has come to the attention of the scientific community owing to the unexpected finding that inhibition of mTOR by rapamycin, an antibiotic with immunosuppressant and chemotherapeutic properties, extends lifespan in diverse animal models. Moreover, rapamycin has been reported to rescue the cellular phenotype in a progeroid syndrome [Hutchinson–Gilford Progeria syndrome (HGPS)] that recapitulates most of the traits of physiological ageing. The promising perspectives raised by these results warrant a better understanding of mTOR signalling and the potential applications of mTOR inhibitors to counteract ageing‐associated diseases and increase longevity. This review is focused on these issues.
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Affiliation(s)
- Camilla Evangelisti
- CNR Institute for Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopedic Institute, Laboratory of Musculoskeletal Cell Biology, Bologna, Italy
| | - Vittoria Cenni
- CNR Institute for Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopedic Institute, Laboratory of Musculoskeletal Cell Biology, Bologna, Italy
| | - Giovanna Lattanzi
- CNR Institute for Molecular Genetics, Unit of Bologna, Bologna, Italy. .,Rizzoli Orthopedic Institute, Laboratory of Musculoskeletal Cell Biology, Bologna, Italy.
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Modulation of TGFbeta 2 levels by lamin A in U2-OS osteoblast-like cells: understanding the osteolytic process triggered by altered lamins. Oncotarget 2016; 6:7424-37. [PMID: 25823658 PMCID: PMC4480690 DOI: 10.18632/oncotarget.3232] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 01/28/2015] [Indexed: 01/17/2023] Open
Abstract
Transforming growth factor beta (TGFbeta) plays an essential role in bone homeostasis and deregulation of TGFbeta occurs in bone pathologies. Patients affected by Mandibuloacral Dysplasia (MADA), a progeroid disease linked to LMNA mutations, suffer from an osteolytic process. Our previous work showed that MADA osteoblasts secrete excess amount of TGFbeta 2, which in turn elicits differentiation of human blood precursors into osteoclasts. Here, we sought to determine how altered lamin A affects TGFbeta signaling. Our results show that wild-type lamin A negatively modulates TGFbeta 2 levels in osteoblast-like U2-OS cells, while the R527H mutated prelamin A as well as farnesylated prelamin A do not, ultimately leading to increased secretion of TGFbeta 2. TGFbeta 2 in turn, triggers the Akt/mTOR pathway and upregulates osteoprotegerin and cathepsin K. TGFbeta 2 neutralization rescues Akt/mTOR activation and the downstream transcriptional effects, an effect also obtained by statins or RAD001 treatment. Our results unravel an unexpected role of lamin A in TGFbeta 2 regulation and indicate rapamycin analogs and neutralizing antibodies to TGFbeta 2 as new potential therapeutic tools for MADA.
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Zuela N, Zwerger M, Levin T, Medalia O, Gruenbaum Y. Impaired mechanical response of an EDMD mutation leads to motility phenotypes that are repaired by loss of prenylation. J Cell Sci 2016; 129:1781-91. [PMID: 27034135 DOI: 10.1242/jcs.184309] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/21/2016] [Indexed: 12/20/2022] Open
Abstract
There are roughly 14 distinct heritable autosomal dominant diseases associated with mutations in lamins A/C, including Emery-Dreifuss muscular dystrophy (EDMD). The mechanical model proposes that the lamin mutations change the mechanical properties of muscle nuclei, leading to cell death and tissue deterioration. Here, we developed an experimental protocol that analyzes the effect of disease-linked lamin mutations on the response of nuclei to mechanical strain in living Caenorhabditis elegans We found that the EDMD mutation L535P disrupts the nuclear mechanical response specifically in muscle nuclei. Inhibiting lamin prenylation rescued the mechanical response of the EDMD nuclei, reversed the muscle phenotypes and led to normal motility. The LINC complex and emerin were also required to regulate the mechanical response of C. elegans nuclei. This study provides evidence to support the mechanical model and offers a potential future therapeutic approach towards curing EDMD.
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Affiliation(s)
- Noam Zuela
- Department of Genetics, Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Monika Zwerger
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, Zurich 8057, Switzerland
| | - Tal Levin
- Department of Genetics, Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, Zurich 8057, Switzerland Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University, Beer-Sheva 84105, Israel
| | - Yosef Gruenbaum
- Department of Genetics, Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Uzer G, Fuchs RK, Rubin J, Thompson WR. Concise Review: Plasma and Nuclear Membranes Convey Mechanical Information to Regulate Mesenchymal Stem Cell Lineage. Stem Cells 2016; 34:1455-63. [PMID: 26891206 DOI: 10.1002/stem.2342] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 12/14/2015] [Accepted: 12/29/2015] [Indexed: 12/21/2022]
Abstract
Numerous factors including chemical, hormonal, spatial, and physical cues determine stem cell fate. While the regulation of stem cell differentiation by soluble factors is well-characterized, the role of mechanical force in the determination of lineage fate is just beginning to be understood. Investigation of the role of force on cell function has largely focused on "outside-in" signaling, initiated at the plasma membrane. When interfaced with the extracellular matrix, the cell uses integral membrane proteins, such as those found in focal adhesion complexes to translate force into biochemical signals. Akin to these outside-in connections, the internal cytoskeleton is physically linked to the nucleus, via proteins that span the nuclear membrane. Although structurally and biochemically distinct, these two forms of mechanical coupling influence stem cell lineage fate and, when disrupted, often lead to disease. Here we provide an overview of how mechanical coupling occurs at the plasma and nuclear membranes. We also discuss the role of force on stem cell differentiation, with focus on the biochemical signals generated at the cell membrane and the nucleus, and how those signals influence various diseases. While the interaction of stem cells with their physical environment and how they respond to force is complex, an understanding of the mechanical regulation of these cells is critical in the design of novel therapeutics to combat diseases associated with aging, cancer, and osteoporosis. Stem Cells 2016;34:1455-1463.
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Affiliation(s)
- Gunes Uzer
- Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Robyn K Fuchs
- School of Health and Rehabilitation Sciences, Department of Physical Therapy, Indiana University, Indianapolis, Indiana, USA
| | - Janet Rubin
- Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| | - William R Thompson
- School of Health and Rehabilitation Sciences, Department of Physical Therapy, Indiana University, Indianapolis, Indiana, USA
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Abstract
Mechanoresponses in mesenchymal stem cells (MSCs) guide both differentiation and function. In this review, we focus on advances in0 our understanding of how the cytoplasmic cytoskeleton, nuclear envelope and nucleoskeleton, which are connected via LINC (Linker of Nucleoskeleton and Cytoskeleton) complexes, are emerging as an integrated dynamic signaling platform to regulate MSC mechanobiology. This dynamic interconnectivity affects mechanical signaling and transfer of signals into the nucleus. In this way, nuclear and LINC-mediated cytoskeletal connectivity play a critical role in maintaining mechanical signaling that affects MSC fate by serving as both mechanosensory and mechanoresponsive structures. We review disease and age related compromises of LINC complexes and nucleoskeleton that contribute to the etiology of musculoskeletal diseases. Finally we invite the idea that acquired dysfunctions of LINC might be a contributing factor to conditions such as aging, microgravity and osteoporosis and discuss potential mechanical strategies to modulate LINC connectivity to combat these conditions.
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Camozzi D, Capanni C, Cenni V, Mattioli E, Columbaro M, Squarzoni S, Lattanzi G. Diverse lamin-dependent mechanisms interact to control chromatin dynamics. Focus on laminopathies. Nucleus 2015; 5:427-40. [PMID: 25482195 PMCID: PMC4164485 DOI: 10.4161/nucl.36289] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Interconnected functional strategies govern chromatin dynamics in eukaryotic cells. In this context, A and B type lamins, the nuclear intermediate filaments, act on diverse platforms involved in tissue homeostasis. On the nuclear side, lamins elicit large scale or fine chromatin conformational changes, affect DNA damage response factors and transcription factor shuttling. On the cytoplasmic side, bridging-molecules, the LINC complex, associate with lamins to coordinate chromatin dynamics with cytoskeleton and extra-cellular signals.
Consistent with such a fine tuning, lamin mutations and/or defects in their expression or post-translational processing, as well as mutations in lamin partner genes, cause a heterogeneous group of diseases known as laminopathies. They include muscular dystrophies, cardiomyopathy, lipodystrophies, neuropathies, and progeroid syndromes. The study of chromatin dynamics under pathological conditions, which is summarized in this review, is shedding light on the complex and fascinating role of the nuclear lamina in chromatin regulation.
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Affiliation(s)
- Daria Camozzi
- a CNR Institute for Molecular Genetics; Unit of Bologna and SC Laboratory of Musculoskeletal Cell Biology; Rizzoli Orthopedic Institute; Bologna, Italy
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Lattanzi G, Ortolani M, Columbaro M, Prencipe S, Mattioli E, Lanzarini C, Maraldi NM, Cenni V, Garagnani P, Salvioli S, Storci G, Bonafè M, Capanni C, Franceschi C. Lamins are rapamycin targets that impact human longevity: a study in centenarians. J Cell Sci 2013; 127:147-57. [PMID: 24155329 DOI: 10.1242/jcs.133983] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The dynamic organisation of the cell nucleus is profoundly modified during growth, development and senescence as a result of changes in chromatin arrangement and gene transcription. A plethora of data suggests that the nuclear lamina is a key player in chromatin dynamics and argues in favour of a major involvement of prelamin A in fundamental mechanisms regulating cellular senescence and organism ageing. As the best model to analyse the role of prelamin A in normal ageing, we used cells from centenarian subjects. We show that prelamin A is accumulated in fibroblasts from centenarians owing to downregulation of its specific endoprotease ZMPSTE24, whereas other nuclear envelope constituents are mostly unaffected and cells do not enter senescence. Accumulation of prelamin A in nuclei of cells from centenarians elicits loss of heterochromatin, as well as recruitment of the inactive form of 53BP1, associated with rapid response to oxidative stress. These effects, including the prelamin-A-mediated increase of nuclear 53BP1, can be reproduced by rapamycin treatment of cells from younger individuals. These data identify prelamin A and 53BP1 as new targets of rapamycin that are associated with human longevity. We propose that the reported mechanisms safeguard healthy ageing in humans through adaptation of the nuclear environment to stress stimuli.
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Affiliation(s)
- Giovanna Lattanzi
- National Research Council of Italy, Institute of Molecular Genetics, Unit of Bologna IOR, 40136 Bologna, Italy
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Capanni C, Bruschi M, Columbaro M, Cuccarolo P, Ravera S, Dufour C, Candiano G, Petretto A, Degan P, Cappelli E. Changes in vimentin, lamin A/C and mitofilin induce aberrant cell organization in fibroblasts from Fanconi anemia complementation group A (FA-A) patients. Biochimie 2013; 95:1838-47. [PMID: 23831462 DOI: 10.1016/j.biochi.2013.06.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 06/21/2013] [Indexed: 01/03/2023]
Abstract
Growing number of publication has proved an increasing of cellular function of the Fanconi anemia proteins. To chromosome stability and DNA repair new roles have been attributed to FA proteins in oxidative stress response and homeostasis, immune response and cytokines sensibility, gene expression. Our work shows a new role for FA-A protein: the organization of the cellular structure. By 2D-PAGE of FA-A and correct fibroblasts treated and untreated with H2O2 we identify different expression of protein involved in the structural organization of nucleus, intermediate filaments and mitochondria. Immunofluorescence and electronic microscopy analysis clearly show an already altered cellular structure in normal culture condition and this worsted after oxidative stress. FA-A cell appears structurally prone to physiologic stress and this could explain part of the phenotype of FA cells.
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Current World Literature. Curr Opin Cardiol 2013; 28:369-79. [DOI: 10.1097/hco.0b013e328360f5be] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Columbaro M, Mattioli E, Maraldi NM, Ortolani M, Gasparini L, D'Apice MR, Postorivo D, Nardone AM, Avnet S, Cortelli P, Liguori R, Lattanzi G. Oct-1 recruitment to the nuclear envelope in adult-onset autosomal dominant leukodystrophy. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1832:411-20. [PMID: 23261988 DOI: 10.1016/j.bbadis.2012.12.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 11/16/2012] [Accepted: 12/10/2012] [Indexed: 01/29/2023]
Abstract
Adult-onset autosomal dominant leukodystrophy (ADLD) is a slowly progressive neurological disorder characterised by pyramidal, cerebellar, and autonomic disturbances. Duplication of the LMNB1 gene is the genetic cause of ADLD, yet the pathogenetic mechanism is not defined. In this study, we analysed cells and muscle tissue from three patients affected by ADLD, carrying an extra copy of the LMNB1 gene. Lamin B1 levels were dramatically increased in ADLD nuclei, both in skin fibroblasts and skeletal muscle fibres. Since lamin B1 is known to bind Oct-1, a transcription factor involved in the oxidative stress pathway, we investigated Oct-1 fate in ADLD. Oct-1 recruitment to the nuclear periphery was increased in ADLD cells, while nucleoplasmic localisation of the transcription factor under oxidative stress conditions was reduced. Importantly, lamin B1 degradation occurring in some, but not all ADLD cell lines, slowed down lamin B1 and Oct-1 accumulation. In skeletal muscle, focal disorganisation of sarcomeres was observed, while IIB-myosin heavy chain, an Oct-1 target gene, was under-expressed and rod-containing fibres were formed. These data show that a high degree of regulation of lamin B1 expression is implicated in the different clinical phenotypes observed in ADLD and show that altered Oct-1 nuclear localisation contributes to the disease phenotype.
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Abstract
The fifth U.K. meeting on nuclear envelope disease and chromatin brought together international experts from across the field of nuclear envelope biology to discuss the advancements in a class of tissue-specific degenerative diseases called the laminopathies. Clinically, these range from relatively mild fat-wasting disorders to the severe premature aging condition known as Hutchinson-Gilford progeria syndrome. Since the first association of the nuclear envelope with human inherited disease in 1994, there has been an exponential increase in an unexpected variety of functions associated with nuclear envelope proteins, ranging from mechanical support and nucleocytoskeletal connections to regulation of chromatin organization and gene expression. This Biochemical Society Focused Meeting reinforced the functional complexity of nuclear-associated diseases, revealed new avenues to be investigated and highlighted the signalling pathways suitable as therapeutic targets.
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