1
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Kono Y, Shimi T. Crosstalk between mitotic reassembly and repair of the nuclear envelope. Nucleus 2024; 15:2352203. [PMID: 38780365 PMCID: PMC11123513 DOI: 10.1080/19491034.2024.2352203] [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: 09/01/2023] [Accepted: 05/01/2024] [Indexed: 05/25/2024] Open
Abstract
In eukaryotic cells, the nuclear envelope (NE) is a membrane partition between the nucleus and the cytoplasm to compartmentalize nuclear contents. It plays an important role in facilitating nuclear functions including transcription, DNA replication and repair. In mammalian cells, the NE breaks down and then reforms during cell division, and in interphase it is restored shortly after the NE rupture induced by mechanical force. In this way, the partitioning effect is regulated through dynamic processes throughout the cell cycle. A failure in rebuilding the NE structure triggers the mixing of nuclear and cytoplasmic contents, leading to catastrophic consequences for the nuclear functions. Whereas the precise details of molecular mechanisms for NE reformation during cell division and NE restoration in interphase are still being investigated, here, we mostly focus on mammalian cells to describe key aspects that have been identified and to discuss the crosstalk between them.
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Affiliation(s)
- Yohei Kono
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Japan
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Takeshi Shimi
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Japan
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2
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Korsten G, Osinga M, Pelle RA, Serweta AK, Hoogenberg B, Kampinga HH, Kapitein LC. Nuclear poly-glutamine aggregates rupture the nuclear envelope and hinder its repair. J Cell Biol 2024; 223:e202307142. [PMID: 39150509 DOI: 10.1083/jcb.202307142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 04/08/2024] [Accepted: 07/30/2024] [Indexed: 08/17/2024] Open
Abstract
Huntington's disease (HD) is caused by a polyglutamine expansion of the huntingtin protein, resulting in the formation of polyglutamine aggregates. The mechanisms of toxicity that result in the complex HD pathology remain only partially understood. Here, we show that nuclear polyglutamine aggregates induce nuclear envelope (NE) blebbing and ruptures that are often repaired incompletely. These ruptures coincide with disruptions of the nuclear lamina and lead to lamina scar formation. Expansion microscopy enabled resolving the ultrastructure of nuclear aggregates and revealed polyglutamine fibrils sticking into the cytosol at rupture sites, suggesting a mechanism for incomplete repair. Furthermore, we found that NE repair factors often accumulated near nuclear aggregates, consistent with stalled repair. These findings implicate nuclear polyQ aggregate-induced loss of NE integrity as a potential contributing factor to Huntington's disease and other polyglutamine diseases.
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Affiliation(s)
- Giel Korsten
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Miriam Osinga
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Robin A Pelle
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Albert K Serweta
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Baukje Hoogenberg
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Harm H Kampinga
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Lukas C Kapitein
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
- Centre for Living Technologies, Alliance TU/e, WUR, UU, UMC Utrecht University, Utrecht, Netherlands
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3
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Yang D, Lai A, Davies A, Janssen AF, Ellis MO, Larrieu D. A novel role for CSA in the regulation of nuclear envelope integrity: uncovering a non-canonical function. Life Sci Alliance 2024; 7:e202402745. [PMID: 39209536 PMCID: PMC11361374 DOI: 10.26508/lsa.202402745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 08/14/2024] [Accepted: 08/20/2024] [Indexed: 09/04/2024] Open
Abstract
Cockayne syndrome (CS) is a premature ageing condition characterized by microcephaly, growth failure, and neurodegeneration. It is caused by mutations in ERCC6 or ERCC8 encoding for Cockayne syndrome B (CSB) and A (CSA) proteins, respectively. CSA and CSB have well-characterized roles in transcription-coupled nucleotide excision repair, responsible for removing bulky DNA lesions, including those caused by UV irradiation. Here, we report that CSA dysfunction causes defects in the nuclear envelope (NE) integrity. NE dysfunction is characteristic of progeroid disorders caused by a mutation in NE proteins, such as Hutchinson-Gilford progeria syndrome. However, it has never been reported in Cockayne syndrome. We observed CSA dysfunction affected LEMD2 incorporation at the NE and increased actin stress fibers that contributed to enhanced mechanical stress to the NE. Altogether, these led to NE abnormalities associated with the activation of the cGAS/STING pathway. Targeting the linker of the nucleoskeleton and cytoskeleton complex was sufficient to rescue these phenotypes. This work reveals NE dysfunction in a progeroid syndrome caused by mutations in a DNA damage repair protein, reinforcing the connection between NE deregulation and ageing.
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Affiliation(s)
- Denny Yang
- https://ror.org/013meh722 Department of Pharmacology, University of Cambridge, Cambridge, UK
- UK Dementia Research Institute, Island Research Building, Cambridge, UK
| | - Austin Lai
- Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge, UK
| | - Amelie Davies
- https://ror.org/013meh722 Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Anne Fj Janssen
- https://ror.org/013meh722 Department of Pharmacology, University of Cambridge, Cambridge, UK
- Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge, UK
| | - Matthew O Ellis
- UK Dementia Research Institute, Island Research Building, Cambridge, UK
| | - Delphine Larrieu
- https://ror.org/013meh722 Department of Pharmacology, University of Cambridge, Cambridge, UK
- Cambridge Institute for Medical Research, The Keith Peters Building, Cambridge, UK
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4
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Copos C, Sun YH, Zhu K, Zhang Y, Reid B, Draper B, Lin F, Yue H, Bernadskaya Y, Zhao M, Mogilner A. Galvanotactic directionality of cell groups depends on group size. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.13.607794. [PMID: 39185145 PMCID: PMC11343102 DOI: 10.1101/2024.08.13.607794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Motile cells migrate directionally in the electric field in a process known as galvanotaxis, important and under-investigated phenomenon in wound healing and development. We previously reported that individual fish keratocyte cells migrate to the cathode in electric fields, that inhibition of PI3 kinase reverses single cells to the anode, and that large cohesive groups of either unperturbed or PI3K-inhibited cells migrate to the cathode. Here we find that small uninhibited cell groups move to the cathode, while small groups of PI3K-inhibited cells move to the anode. Small groups move faster than large groups, and groups of unperturbed cells move faster than PI3K-inhibited cell groups of comparable sizes. Shapes and sizes of large groups change little when they start migrating, while size and shapes of small groups change significantly, lamellipodia disappear from the rear edges of these groups, and their shapes start to resemble giant single cells. Our results are consistent with the computational model, according to which cells inside and at the edge of the groups pool their propulsive forces to move but interpret directional signals differently. Namely, cells in the group interior are directed to the cathode independently of their chemical state. Meanwhile, the edge cells behave like individual cells: they are directed to the cathode/anode in uninhibited/PI3K-inhibited groups, respectively. As a result, all cells drive uninhibited groups to the cathode, while larger PI3K-inhibited groups are directed by cell majority in the group interior to the cathode, while majority of the edge cells in small groups win the tug-of-war driving these groups to the anode.
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Affiliation(s)
- Calina Copos
- Department of Biology and Department of Mathematics, Northeastern University, Boston, MA 02115
| | - Yao-Hui Sun
- Department of Ophthalmology and Vision Science and Department of Dermatology, School of Medicine, University of California, Davis, Sacramento, CA 95817
| | - Kan Zhu
- Department of Ophthalmology and Vision Science and Department of Dermatology, School of Medicine, University of California, Davis, Sacramento, CA 95817
| | - Yan Zhang
- Department of Occupational and Environmental Health, Hangzhou Normal University School of Public Health, Hangzhou 311121, China
| | - Brian Reid
- Department of Ophthalmology and Vision Science and Department of Dermatology, School of Medicine, University of California, Davis, Sacramento, CA 95817
| | - Bruce Draper
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616
| | - Francis Lin
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Haicen Yue
- Department of Physics, University of Vermont, Burlington, VT 05405
| | - Yelena Bernadskaya
- Courant Institute and Department of Biology, New York University, New York, NY 10012
| | - Min Zhao
- Department of Ophthalmology and Vision Science and Department of Dermatology, School of Medicine, University of California, Davis, Sacramento, CA 95817
| | - Alex Mogilner
- Courant Institute and Department of Biology, New York University, New York, NY 10012
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5
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Liu H, Su P, Li Y, Hoover A, Hu S, King SA, Zhao J, Guan JL, Chen SY, Zhao Y, Tan M, Wu X. VAMP2 controls murine epidermal differentiation and carcinogenesis by regulation of nucleophagy. Dev Cell 2024; 59:2005-2016.e4. [PMID: 38810653 PMCID: PMC11303110 DOI: 10.1016/j.devcel.2024.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/16/2024] [Accepted: 05/03/2024] [Indexed: 05/31/2024]
Abstract
Differentiation of murine epidermal stem/progenitor cells involves the permanent withdrawal from the cell cycle, the synthesis of various protein and lipid components for the cornified envelope, and the controlled dissolution of cellular organelles and nuclei. Deregulated epidermal differentiation contributes to the development of various skin diseases, including skin cancers. With a genome-wide shRNA screen, we identified vesicle-associated membrane protein 2 (VAMP2) as a critical factor involved in skin differentiation. Deletion of VAMP2 leads to aberrant skin stratification and enucleation in vivo. With quantitative proteomics, we further identified an autophagy protein, focal adhesion kinase family interacting protein of 200 kDa (FIP200), as a binding partner of VAMP2. Additionally, we showed that both VAMP2 and FIP200 are critical for murine keratinocyte enucleation and epidermal differentiation. Loss of VAMP2 or FIP200 enhances cutaneous carcinogenesis in vivo. Together, our findings identify important molecular mechanisms underlying epidermal differentiation and skin tumorigenesis.
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Affiliation(s)
- Han Liu
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Peihong Su
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Yuanyuan Li
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Alex Hoover
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Sophie Hu
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Sarah A King
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Jing Zhao
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Jun-Lin Guan
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Shao-Yu Chen
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Yingming Zhao
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA
| | - Minjia Tan
- The Chemical Proteomics Center and State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, P.R. China
| | - Xiaoyang Wu
- Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA.
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6
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Wada E, Susumu N, Kaya M, Hayashi YK. Characteristics of nuclear architectural abnormalities of myotubes differentiated from Lmna H222P/H222P skeletal muscle cells. In Vitro Cell Dev Biol Anim 2024; 60:781-792. [PMID: 38724872 DOI: 10.1007/s11626-024-00915-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 04/22/2024] [Indexed: 08/03/2024]
Abstract
The presence of nuclear architectural abnormalities is a hallmark of the nuclear envelopathies, which are a group of diseases caused by mutations in genes encoding nuclear envelope proteins. Mutations in the lamin A/C gene cause several diseases, named laminopathies, including muscular dystrophies, progeria syndromes, and lipodystrophy. A mouse model carrying with the LmnaH222P/H222P mutation (H222P) was shown to develop severe cardiomyopathy but only mild skeletal myopathy, although abnormal nuclei were observed in their striated muscle. In this report, we analyzed the abnormal-shaped nuclei in myoblasts and myotubes isolated from skeletal muscle of H222P mice, and evaluated the expression of nuclear envelope proteins in these abnormal myonuclei. Primary skeletal muscle cells from H222P mice proliferated and efficiently differentiated into myotubes in vitro, similarly to those from wild-type mice. During cell proliferation, few abnormal-shaped nuclei were detected; however, numerous markedly abnormal myonuclei were observed in myotubes from H222P mice on days 5 and 7 of differentiation. Time-lapse observation demonstrated that myonuclei with a normal shape maintained their normal shape, whereas abnormal-shaped myonuclei remained abnormal for at least 48 h during differentiation. Among the abnormal-shaped myonuclei, 65% had a bleb with a string structure, and 35% were severely deformed. The area and nuclear contents of the nuclear blebs were relatively stable, whereas the myocytes with nuclear blebs were actively fused within primary myotubes. Although myonuclei were markedly deformed, the deposition of DNA damage marker (γH2AX) or apoptotic marker staining was rarely observed. Localizations of lamin A/C and emerin were maintained within the blebs, strings, and severely deformed regions of myonuclei; however, lamin B1, nesprin-1, and a nuclear pore complex protein were absent in these abnormal regions. These results demonstrate that nuclear membranes from H222P skeletal muscle cells do not rupture and are resistant to DNA damage, despite these marked morphological changes.
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Affiliation(s)
- Eiji Wada
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Nao Susumu
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Motoshi Kaya
- Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Yukiko K Hayashi
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan.
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7
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Caruso AP, Logue JS. The biophysics of cell motility through mechanochemically challenging environments. Curr Opin Cell Biol 2024; 90:102404. [PMID: 39053178 DOI: 10.1016/j.ceb.2024.102404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/25/2024] [Accepted: 07/05/2024] [Indexed: 07/27/2024]
Abstract
Challenging mechanochemical environments (i.e., with varied mechanical and adhesive properties) are now known to induce a wide range of adaptive phenomena in motile cells. For instance, confinement and low adhesion may trigger a phenotypic transition to fast amoeboid (leader bleb-based) migration. The molecular mechanisms that underly these phenomena are beginning to be understood. Due to its size, the mechanical properties of the nucleus have been shown to limit and facilitate cell migration. Additionally, the activity of various transient receptor potential (TRP) channels is now known to be integral to cell migration in response to a multitude of biophysical stimuli. How cells integrate signals from the nucleus and plasma membrane, however, is unclear. The development of therapeutics that suppress cancer or enhance immune cell migration for immuno-oncology applications, etc., will require additional work to completely understand the molecular mechanisms that enable cells to navigate mechanochemically challenging environments.
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Affiliation(s)
- Alexa P Caruso
- Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Ave, Albany, NY 12208, USA
| | - Jeremy S Logue
- Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Ave, Albany, NY 12208, USA.
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8
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Gunn AL, Yashchenko AI, Dubrulle J, Johnson J, Hatch EM. A high-content screen reveals new regulators of nuclear membrane stability. Sci Rep 2024; 14:6013. [PMID: 38472343 PMCID: PMC10933478 DOI: 10.1038/s41598-024-56613-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 03/08/2024] [Indexed: 03/14/2024] Open
Abstract
Nuclear membrane rupture is a physiological response to multiple in vivo processes, such as cell migration, that can cause extensive genome instability and upregulate invasive and inflammatory pathways. However, the underlying molecular mechanisms of rupture are unclear and few regulators have been identified. In this study, we developed a reporter that is size excluded from re-compartmentalization following nuclear rupture events. This allows for robust detection of factors influencing nuclear integrity in fixed cells. We combined this with an automated image analysis pipeline in a high-content siRNA screen to identify new proteins that both increase and decrease nuclear rupture frequency in cancer cells. Pathway analysis identified an enrichment of nuclear membrane and ER factors in our hits and we demonstrate that one of these, the protein phosphatase CTDNEP1, is required for nuclear stability. Analysis of known rupture determinants, including an automated quantitative analysis of nuclear lamina gaps, are consistent with CTDNEP1 acting independently of actin and nuclear lamina organization. Our findings provide new insights into the molecular mechanism of nuclear rupture and define a highly adaptable program for rupture analysis that removes a substantial barrier to new discoveries in the field.
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Affiliation(s)
- Amanda L Gunn
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Artem I Yashchenko
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Julien Dubrulle
- Cellular Imaging Shared Resource, The Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Jodiene Johnson
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, Seattle, WA, USA
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA, USA
| | - Emily M Hatch
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, Seattle, WA, USA.
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9
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Di Bona M, Bakhoum SF. Micronuclei and Cancer. Cancer Discov 2024; 14:214-226. [PMID: 38197599 PMCID: PMC11265298 DOI: 10.1158/2159-8290.cd-23-1073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/20/2023] [Accepted: 12/18/2023] [Indexed: 01/11/2024]
Abstract
Chromosome-containing micronuclei are a feature of human cancer. Micronuclei arise from chromosome mis-segregation and characterize tumors with elevated rates of chromosomal instability. Although their association with cancer has been long recognized, only recently have we broadened our understanding of the mechanisms that govern micronuclei formation and their role in tumor progression. In this review, we provide a brief historical account of micronuclei, depict the mechanisms underpinning their creation, and illuminate their capacity to propel tumor evolution through genetic, epigenetic, and transcriptional transformations. We also posit the prospect of leveraging micronuclei as biomarkers and therapeutic targets in chromosomally unstable cancers. SIGNIFICANCE Micronuclei in chromosomally unstable cancer cells serve as pivotal catalysts for cancer progression, instigating transformative genomic, epigenetic, and transcriptional alterations. This comprehensive review not only synthesizes our present comprehension but also outlines a framework for translating this knowledge into pioneering biomarkers and therapeutics, thereby illuminating novel paths for personalized cancer management.
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Affiliation(s)
- Melody Di Bona
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Samuel F. Bakhoum
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
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10
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van Heerden D, Klima S, van den Bout I. How nuclear envelope dynamics can direct laminopathy phenotypes. Curr Opin Cell Biol 2024; 86:102290. [PMID: 38048657 DOI: 10.1016/j.ceb.2023.102290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/25/2023] [Accepted: 11/09/2023] [Indexed: 12/06/2023]
Abstract
The nuclear envelope separates the genome from the cytoplasmic environment. However, the nuclear envelope is also physically associated with the genome and exerts influence on gene expression and genome modification. The nucleus is dynamic, changing shape and responding to cell movement, disassembling and assembling during cell division, and undergoing rupture and repair. These dynamics can be impacted by genetic disease, leading to a family of diseases called laminopathies. Their disparate phenotypes suggest that multiple processes are affected. We highlight three such processes here, which we believe can be used to classify most of the laminopathies. While much still needs to be learned, some commonalities between these processes, such as proteins involved in nuclear envelope formation and rupture repair, may drive a variety of laminopathies. Here we review the latest information regarding nuclear dynamics and its role in laminopathies related to mutations in the nuclear lamina and linker of nucleoskeleton and cytoskeleton complex (LINC) proteins.
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Affiliation(s)
- David van Heerden
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, South Africa; Centre for Neuroendocrinology, Department of Immunology, Faculty of Health Sciences, University of Pretoria, South Africa
| | - Stefanie Klima
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, South Africa; Centre for Neuroendocrinology, Department of Immunology, Faculty of Health Sciences, University of Pretoria, South Africa
| | - Iman van den Bout
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, South Africa; Centre for Neuroendocrinology, Department of Immunology, Faculty of Health Sciences, University of Pretoria, South Africa.
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11
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Pho M, Berrada Y, Gunda A, Lavallee A, Chiu K, Padam A, Currey ML, Stephens AD. Actin contraction controls nuclear blebbing and rupture independent of actin confinement. Mol Biol Cell 2024; 35:ar19. [PMID: 38088876 PMCID: PMC10881147 DOI: 10.1091/mbc.e23-07-0292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 11/03/2023] [Accepted: 11/27/2023] [Indexed: 01/14/2024] Open
Abstract
The nucleus is a mechanically stable compartment of the cell that contains the genome and performs many essential functions. Nuclear mechanical components chromatin and lamins maintain nuclear shape, compartmentalization, and function by resisting antagonistic actin contraction and confinement. Studies have yet to compare chromatin and lamins perturbations side-by-side as well as modulated actin contraction while holding confinement constant. To accomplish this, we used nuclear localization signal green fluorescent protein to measure nuclear shape and rupture in live cells with chromatin and lamin perturbations. We then modulated actin contraction while maintaining actin confinement measured by nuclear height. Wild type, chromatin decompaction, and lamin B1 null present bleb-based nuclear deformations and ruptures dependent on actin contraction and independent of actin confinement. Actin contraction inhibition by Y27632 decreased nuclear blebbing and ruptures while activation by CN03 increased rupture frequency. Lamin A/C null results in overall abnormal shape also reliant on actin contraction, but similar blebs and ruptures as wild type. Increased DNA damage is caused by nuclear blebbing or abnormal shape which can be relieved by inhibition of actin contraction which rescues nuclear shape and decreases DNA damage levels in all perturbations. Thus, actin contraction drives nuclear blebbing, bleb-based ruptures, and abnormal shape independent of changes in actin confinement.
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Affiliation(s)
- Mai Pho
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
| | - Yasmin Berrada
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
| | - Aachal Gunda
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
| | - Anya Lavallee
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
| | - Katherine Chiu
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
| | - Arimita Padam
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
| | - Marilena L. Currey
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
| | - Andrew D. Stephens
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003
- Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003
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12
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Sobo JM, Alagna NS, Sun SX, Wilson KL, Reddy KL. Lamins: The backbone of the nucleocytoskeleton interface. Curr Opin Cell Biol 2024; 86:102313. [PMID: 38262116 DOI: 10.1016/j.ceb.2023.102313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 12/14/2023] [Accepted: 12/15/2023] [Indexed: 01/25/2024]
Abstract
The nuclear lamina (NL) is a crucial component of the inner nuclear membrane (INM) and consists of lamin filaments and associated proteins. Lamins are type V intermediate filament proteins essential for maintaining the integrity and mechanical properties of the nucleus. In human cells, 'B-type' lamins (lamin B1 and lamin B2) are ubiquitously expressed, while 'A-type' lamins (lamin A, lamin C, and minor isoforms) are expressed in a tissue- and development-specific manner. Lamins homopolymerize to form filaments that localize primarily near the INM, but A-type lamins also localize to and function in the nucleoplasm. Lamins play central roles in the assembly, structure, positioning, and mechanics of the nucleus, modulating cell signaling and influencing development, differentiation, and other activities. This review highlights recent findings on the structure and regulation of lamin filaments, providing insights into their multifaceted functions, including their role as "mechanosensors", delving into the emerging significance of lamin filaments as vital links between cytoskeletal and nuclear structures, chromatin organization, and the genome.
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Affiliation(s)
- Joan M Sobo
- Department of Biological Chemistry, Center for Epigenetics, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Nicholas S Alagna
- Department of Biological Chemistry, Center for Epigenetics, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Sean X Sun
- Department of Mechanical Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Katherine L Wilson
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Karen L Reddy
- Department of Biological Chemistry, Center for Epigenetics, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Sidney Kimmel Comprehensive Cancer Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA.
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13
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Halfmann CT, Scott KL, Sears RM, Roux KJ. Mechanisms by which barrier-to-autointegration factor regulates dynamics of nucleocytoplasmic leakage and membrane repair following nuclear envelope rupture. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.21.572811. [PMID: 38187776 PMCID: PMC10769424 DOI: 10.1101/2023.12.21.572811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The nuclear envelope (NE) creates a barrier between the cytosol and nucleus during interphase that is key for cellular compartmentalization and protecting genomic DNA. NE rupture can expose genomic DNA to the cytosol and allow admixture of the nuclear and cytosolic constituents, a proposed mechanism of cancer and NE-associated diseases. Barrier-to-autointegration factor (BAF) is a DNA-binding protein that localizes to NE ruptures where it recruits LEM-domain proteins, A-type lamins, and participates in rupture repair. To further reveal the mechanisms by which BAF responds to and aids in repairing NE ruptures, we investigated known properties of BAF including LEM domain binding, lamin binding, compartmentalization, phosphoregulation of DNA binding, and BAF dimerization. We demonstrate that it is the cytosolic population of BAF that functionally repairs NE ruptures, and phosphoregulation of BAF's DNA-binding that enables its ability to facilitate that repair. Interestingly, BAF's LEM or lamin binding activity appears dispensable for its role in functional repair. Furthermore, we demonstrate that BAF functions to reduce the extent of leakage though NE ruptures, suggesting that BAF effectively forms a diffusion barrier prior to NE repair. Collectively, these results enhances our knowledge of the mechanisms by which BAF responds to NE ruptures and facilitates their repair.
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Affiliation(s)
| | - Kelsey L. Scott
- Enabling Technologies Group, Sanford Research, Sioux Falls SD
| | - Rhiannon M. Sears
- Enabling Technologies Group, Sanford Research, Sioux Falls SD
- Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD
| | - Kyle J. Roux
- Enabling Technologies Group, Sanford Research, Sioux Falls SD
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls SD
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14
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Coy S, Cheng B, Lee JS, Rashid R, Browning L, Xu Y, Chakrabarty SS, Yapp C, Chan S, Tefft JB, Scott E, Spektor A, Ligon KL, Baker GJ, Pellman D, Sorger PK, Santagata S. 2D and 3D multiplexed subcellular profiling of nuclear instability in human cancer. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.07.566063. [PMID: 37986801 PMCID: PMC10659270 DOI: 10.1101/2023.11.07.566063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Nuclear atypia, including altered nuclear size, contour, and chromatin organization, is ubiquitous in cancer cells. Atypical primary nuclei and micronuclei can rupture during interphase; however, the frequency, causes, and consequences of nuclear rupture are unknown in most cancers. We demonstrate that nuclear envelope rupture is surprisingly common in many human cancers, particularly glioblastoma. Using highly-multiplexed 2D and super-resolution 3D-imaging of glioblastoma tissues and patient-derived xenografts and cells, we link primary nuclear rupture with reduced lamin A/C and micronuclear rupture with reduced lamin B1. Moreover, ruptured glioblastoma cells activate cGAS-STING-signaling involved in innate immunity. We observe that local patterning of cell states influences tumor spatial organization and is linked to both lamin expression and rupture frequency, with neural-progenitor-cell-like states exhibiting the lowest lamin A/C levels and greatest susceptibility to primary nuclear rupture. Our study reveals that nuclear instability is a core feature of cancer, and links nuclear integrity, cell state, and immune signaling.
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Affiliation(s)
- Shannon Coy
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Brian Cheng
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Jong Suk Lee
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Rumana Rashid
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Lindsay Browning
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Yilin Xu
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Sankha S. Chakrabarty
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Clarence Yapp
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Sabrina Chan
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Juliann B. Tefft
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Emily Scott
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Alexander Spektor
- Department of Radiation Oncology, Brigham and Women’s Hospital and Dana Farber Cancer Institute, Boston, MA, USA
| | - Keith L. Ligon
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Gregory J. Baker
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - David Pellman
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Peter K. Sorger
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Sandro Santagata
- Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
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15
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Barger SR, Penfield L, Bahmanyar S. Nuclear envelope assembly relies on CHMP-7 in the absence of BAF-LEM-mediated hole closure. J Cell Sci 2023; 136:jcs261385. [PMID: 37795681 PMCID: PMC10668030 DOI: 10.1242/jcs.261385] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 09/21/2023] [Indexed: 10/06/2023] Open
Abstract
Barrier-to-autointegration factor (BAF) protein is a DNA-binding protein that crosslinks chromatin to allow mitotic nuclear envelope (NE) assembly. The LAP2-emerin-MAN1 (LEM)-domain protein LEMD2 and ESCRT-II/III hybrid protein CHMP7 close NE holes surrounding spindle microtubules (MTs). BAF binds LEM-domain family proteins to repair NE ruptures in interphase, but whether BAF-LEM binding participates in NE hole closure around spindle MTs is not known. Here, we took advantage of the stereotypical event of NE formation in fertilized Caenorhabditis elegans oocytes to show that BAF-LEM binding and LEM-2-CHMP-7 have distinct roles in NE closure around spindle MTs. LEM-2 and EMR-1 (homologs of LEMD2 and emerin) function redundantly with BAF-1 (the C. elegans BAF protein) in NE closure. Compromising BAF-LEM binding revealed an additional role for EMR-1 in the maintenance of the NE permeability barrier. In the absence of BAF-LEM binding, LEM-2-CHMP-7 was required for NE assembly and embryo survival. The winged helix domain of LEM-2 recruits CHMP-7 to the NE in C. elegans and a LEM-2-independent nucleoplasmic pool of CHMP-7 also contributes to NE stability. Thus, NE hole closure surrounding spindle MTs requires redundant mechanisms that safeguard against failure in NE assembly to support embryogenesis.
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Affiliation(s)
- Sarah R. Barger
- Yale University, Department of Molecular, Cellular, Developmental Biology, 266 Whitney Ave., New Haven, CT 06511, USA
| | - Lauren Penfield
- Yale University, Department of Molecular, Cellular, Developmental Biology, 266 Whitney Ave., New Haven, CT 06511, USA
| | - Shirin Bahmanyar
- Yale University, Department of Molecular, Cellular, Developmental Biology, 266 Whitney Ave., New Haven, CT 06511, USA
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16
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Lee GE, Byun J, Lee CJ, Cho YY. Molecular Mechanisms for the Regulation of Nuclear Membrane Integrity. Int J Mol Sci 2023; 24:15497. [PMID: 37895175 PMCID: PMC10607757 DOI: 10.3390/ijms242015497] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/19/2023] [Accepted: 10/22/2023] [Indexed: 10/29/2023] Open
Abstract
The nuclear membrane serves a critical role in protecting the contents of the nucleus and facilitating material and signal exchange between the nucleus and cytoplasm. While extensive research has been dedicated to topics such as nuclear membrane assembly and disassembly during cell division, as well as interactions between nuclear transmembrane proteins and both nucleoskeletal and cytoskeletal components, there has been comparatively less emphasis on exploring the regulation of nuclear morphology through nuclear membrane integrity. In particular, the role of type II integral proteins, which also function as transcription factors, within the nuclear membrane remains an area of research that is yet to be fully explored. The integrity of the nuclear membrane is pivotal not only during cell division but also in the regulation of gene expression and the communication between the nucleus and cytoplasm. Importantly, it plays a significant role in the development of various diseases. This review paper seeks to illuminate the biomolecules responsible for maintaining the integrity of the nuclear membrane. It will delve into the mechanisms that influence nuclear membrane integrity and provide insights into the role of type II membrane protein transcription factors in this context. Understanding these aspects is of utmost importance, as it can offer valuable insights into the intricate processes governing nuclear membrane integrity. Such insights have broad-reaching implications for cellular function and our understanding of disease pathogenesis.
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Affiliation(s)
- Ga-Eun Lee
- BK21-4th, and BRL, College of Pharmacy, The Catholic University of Korea, 43, Jibong-ro, Wonmi-gu, Bucheon-si 14662, Gyeonggi-do, Republic of Korea; (G.-E.L.); (J.B.)
| | - Jiin Byun
- BK21-4th, and BRL, College of Pharmacy, The Catholic University of Korea, 43, Jibong-ro, Wonmi-gu, Bucheon-si 14662, Gyeonggi-do, Republic of Korea; (G.-E.L.); (J.B.)
| | - Cheol-Jung Lee
- Research Center for Materials Analysis, Korea Basic Science Institute, 169-148, Gwahak-ro, Yuseong-gu, Daejeon 34133, Chungcheongnam-do, Republic of Korea
| | - Yong-Yeon Cho
- BK21-4th, and BRL, College of Pharmacy, The Catholic University of Korea, 43, Jibong-ro, Wonmi-gu, Bucheon-si 14662, Gyeonggi-do, Republic of Korea; (G.-E.L.); (J.B.)
- RCD Control and Material Research Institute, The Catholic University of Korea, 43, Jibong-ro, Wonmi-gu, Bucheon-si 14662, Gyeonggi-do, Republic of Korea
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17
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Berg IK, Currey ML, Gupta S, Berrada Y, Nguyen BV, Pho M, Patteson AE, Schwarz JM, Banigan EJ, Stephens AD. Transcription inhibition suppresses nuclear blebbing and rupture independently of nuclear rigidity. J Cell Sci 2023; 136:jcs261547. [PMID: 37756607 PMCID: PMC10660790 DOI: 10.1242/jcs.261547] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
Chromatin plays an essential role in the nuclear mechanical response and determining nuclear shape, which maintain nuclear compartmentalization and function. However, major genomic functions, such as transcription activity, might also impact cell nuclear shape via blebbing and rupture through their effects on chromatin structure and dynamics. To test this idea, we inhibited transcription with several RNA polymerase II inhibitors in wild-type cells and perturbed cells that presented increased nuclear blebbing. Transcription inhibition suppressed nuclear blebbing for several cell types, nuclear perturbations and transcription inhibitors. Furthermore, transcription inhibition suppressed nuclear bleb formation, bleb stabilization and bleb-based nuclear ruptures. Interestingly, transcription inhibition did not alter the histone H3 lysine 9 (H3K9) modification state, nuclear rigidity, and actin compression and contraction, which typically control nuclear blebbing. Polymer simulations suggested that RNA polymerase II motor activity within chromatin could drive chromatin motions that deform the nuclear periphery. Our data provide evidence that transcription inhibition suppresses nuclear blebbing and rupture, in a manner separate and distinct from chromatin rigidity.
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Affiliation(s)
- Isabel K. Berg
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
- Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Marilena L. Currey
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Sarthak Gupta
- Department of Physics and BioInspired Syracuse, Syracuse University, Syracuse, NY 13244, USA
| | - Yasmin Berrada
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Bao V. Nguyen
- Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Mai Pho
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Alison E. Patteson
- Department of Physics and BioInspired Syracuse, Syracuse University, Syracuse, NY 13244, USA
| | - J. M. Schwarz
- Department of Physics and BioInspired Syracuse, Syracuse University, Syracuse, NY 13244, USA
- Indian Creek Farm, Ithaca, NY 14850, USA
| | - Edward J. Banigan
- Institute of Medical Engineering & Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Andrew D. Stephens
- Biology Department, University of Massachusetts Amherst, Amherst, MA 01003, USA
- Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
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18
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Tang M, Suraweera A, Nie X, Li Z, Lai P, Wells JW, O'Byrne KJ, Woods RJ, Bolderson E, Richard DJ. Mono-phosphorylation at Ser4 of barrier-to-autointegration factor (Banf1) significantly reduces its DNA binding capability by inducing critical changes in its local conformation and DNA binding surface. Phys Chem Chem Phys 2023; 25:24657-24677. [PMID: 37665626 DOI: 10.1039/d3cp02302h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Barrier-to-autointegration factor (Banf1) is a small DNA-bridging protein. The binding status of Banf1 to DNA is regulated by its N-terminal phosphorylation and dephosphorylation, which plays a critical role in cell proliferation. Banf1 can be phosphorylated at Ser4 into mono-phosphorylated Banf1, which is further phosphorylated at Thr3 to form di-phosphorylated Banf1. It was observed decades ago that mono-phosphorylated Banf1 cannot bind to DNA. However, the underlying molecular- and atomic-level mechanisms remain unclear. A clear understanding of these mechanisms will aid in interfering with the cell proliferation process for better global health. Herein, we explored the detailed atomic bases of unphosphorylated Banf1-DNA binding and how mono- and di-phosphorylation of Banf1 impair these atomic bases to eliminate its DNA-binding capability, followed by exploring the DNA-binding capability of mono- and di-phosphorylation Banf1, using comprehensive and systematic molecular modelling and molecular dynamics simulations. This work presented in detail the residue-level binding energies, hydrogen bonds and water bridges between Banf1 and DNA, some of which have not been reported. Moreover, we revealed that mono-phosphorylation of Banf1 causes its N-terminal secondary structure changes, which in turn induce significant changes in Banf1's DNA binding surface, thus eliminating its DNA-binding capability. At the atomic level, we also uncovered the alterations in interactions due to the induction of mono-phosphorylation that result in the N-terminal secondary structure changes of Banf1. Additionally, our modelling showed that phosphorylated Banf1 with their dominant N-terminal secondary structures bind to DNA with a significantly lower affinity and the docked binding pose are not stable in MD simulations. These findings help future studies in predicting effect of mutations in Banf1 on its DNA-binding capability and open a novel avenue for the development of therapeutics such as cancer drugs, targeting cell proliferation by inducing conformational changes in Banf1's N-terminal domain.
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Affiliation(s)
- Ming Tang
- Cancer and Ageing Research Program, Centre for Genomics and Personalised Health, Queensland University of Technology at the Translational Research Institute Australia, Brisbane, Australia.
- Faculty of Medicine, Frazer Institute, The University of Queensland at the Translational Research Institute Australia, Brisbane, Australia
| | - Amila Suraweera
- Cancer and Ageing Research Program, Centre for Genomics and Personalised Health, Queensland University of Technology at the Translational Research Institute Australia, Brisbane, Australia.
| | - Xuqiang Nie
- Cancer and Ageing Research Program, Centre for Genomics and Personalised Health, Queensland University of Technology at the Translational Research Institute Australia, Brisbane, Australia.
- College of Pharmacy, Key Lab of the Basic Pharmacology of the Ministry of Education, Zunyi Medical University, Zunyi, China
| | - Zilin Li
- School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou 450001, China
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, Australia
| | - Pinglin Lai
- Academy of Orthopedics Guangdong Province, Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Diseases, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China
| | - James W Wells
- Faculty of Medicine, Frazer Institute, The University of Queensland at the Translational Research Institute Australia, Brisbane, Australia
| | - Kenneth J O'Byrne
- Cancer and Ageing Research Program, Centre for Genomics and Personalised Health, Queensland University of Technology at the Translational Research Institute Australia, Brisbane, Australia.
- Princess Alexandra Hospital, Brisbane, Australia
| | - Robert J Woods
- Complex Carbohydrate Research Centre, University of Georgia, 315 Riverbend Rd, Athens, GA, 30602, USA
| | - Emma Bolderson
- Cancer and Ageing Research Program, Centre for Genomics and Personalised Health, Queensland University of Technology at the Translational Research Institute Australia, Brisbane, Australia.
| | - Derek J Richard
- Cancer and Ageing Research Program, Centre for Genomics and Personalised Health, Queensland University of Technology at the Translational Research Institute Australia, Brisbane, Australia.
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19
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Gunn AL, Yashchenko AI, Dubrulle J, Johnson J, Hatch EM. A high-content screen reveals new regulators of nuclear membrane stability. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.30.542944. [PMID: 37398267 PMCID: PMC10312541 DOI: 10.1101/2023.05.30.542944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Nuclear membrane rupture is a physiological response to multiple in vivo processes, such as cell migration, that can cause extensive genome instability and upregulate invasive and inflammatory pathways. However, the underlying molecular mechanisms of rupture are unclear and few regulators have been identified. In this study, we developed a reporter that is size excluded from re-compartmentalization following nuclear rupture events. This allows for robust detection of factors influencing nuclear integrity in fixed cells. We combined this with an automated image analysis pipeline in a high-content siRNA screen to identify new proteins that both increase and decrease nuclear rupture frequency in cancer cells. Pathway analysis identified an enrichment of nuclear membrane and ER factors in our hits and we demonstrate that one of these, the protein phosphatase CTDNEP1, is required for nuclear stability. Further analysis of known rupture contributors, including a newly developed automated quantitative analysis of nuclear lamina gaps, strongly suggests that CTDNEP1 acts in a new pathway. Our findings provide new insights into the molecular mechanism of nuclear rupture and define a highly adaptable program for rupture analysis that removes a substantial barrier to new discoveries in the field.
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Affiliation(s)
- Amanda L. Gunn
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, 1100 Fairview Ave, Seattle, Washington 98109, USA
| | - Artem I. Yashchenko
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, 1100 Fairview Ave, Seattle, Washington 98109, USA
| | - Julien Dubrulle
- Cellular Imaging Shared Resource, The Fred Hutchinson Cancer Center, 1100 Fairview Ave, Seattle, Washington 98109, USA
| | - Jodiene Johnson
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, 1100 Fairview Ave, Seattle, Washington 98109, USA
| | - Emily M. Hatch
- Divisions of Basic Sciences and Human Biology, The Fred Hutchinson Cancer Center, 1100 Fairview Ave, Seattle, Washington 98109, USA
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20
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Olson AT, Kang Y, Ladha AM, Zhu S, Lim CB, Nabet B, Lagunoff M, Gujral TS, Geballe AP. Polypharmacology-based kinome screen identifies new regulators of KSHV reactivation. PLoS Pathog 2023; 19:e1011169. [PMID: 37669313 PMCID: PMC10503724 DOI: 10.1371/journal.ppat.1011169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 09/15/2023] [Accepted: 08/16/2023] [Indexed: 09/07/2023] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) causes several human diseases including Kaposi's sarcoma (KS), a leading cause of cancer in Africa and in patients with AIDS. KS tumor cells harbor KSHV predominantly in a latent form, while typically <5% contain lytic replicating virus. Because both latent and lytic stages likely contribute to cancer initiation and progression, continued dissection of host regulators of this biological switch will provide insights into fundamental pathways controlling the KSHV life cycle and related disease pathogenesis. Several cellular protein kinases have been reported to promote or restrict KSHV reactivation, but our knowledge of these signaling mediators and pathways is incomplete. We employed a polypharmacology-based kinome screen to identify specific kinases that regulate KSHV reactivation. Those identified by the screen and validated by knockdown experiments included several kinases that enhance lytic reactivation: ERBB2 (HER2 or neu), ERBB3 (HER3), ERBB4 (HER4), MKNK2 (MNK2), ITK, TEC, and DSTYK (RIPK5). Conversely, ERBB1 (EGFR1 or HER1), MKNK1 (MNK1) and FRK (PTK5) were found to promote the maintenance of latency. Mechanistic characterization of ERBB2 pro-lytic functions revealed a signaling connection between ERBB2 and the activation of CREB1, a transcription factor that drives KSHV lytic gene expression. These studies provided a proof-of-principle application of a polypharmacology-based kinome screen for the study of KSHV reactivation and enabled the discovery of both kinase inhibitors and specific kinases that regulate the KSHV latent-to-lytic replication switch.
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Affiliation(s)
- Annabel T. Olson
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Yuqi Kang
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Anushka M. Ladha
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Songli Zhu
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Chuan Bian Lim
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Behnam Nabet
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
| | - Michael Lagunoff
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Taranjit S. Gujral
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
- Department of Pharmacology, University of Washington, Seattle, Washington, United States of America
| | - Adam P. Geballe
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
- Division of Clinical Research, Fred Hutchinson Cancer Center, Seattle, Washington, United States of America
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
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21
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Kamikawa Y, Wu Z, Nakazawa N, Ito T, Saito A, Imaizumi K. Impact of cell cycle on repair of ruptured nuclear envelope and sensitivity to nuclear envelope stress in glioblastoma. Cell Death Discov 2023; 9:233. [PMID: 37422516 DOI: 10.1038/s41420-023-01534-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 06/15/2023] [Accepted: 06/28/2023] [Indexed: 07/10/2023] Open
Abstract
The nuclear envelope (NE) is often challenged by various stresses (known as "NE stress"), leading to its dysfunction. Accumulating evidence has proven the pathological relevance of NE stress in numerous diseases ranging from cancer to neurodegenerative diseases. Although several proteins involved in the reassembly of the NE after mitosis have been identified as the NE repair factors, the regulatory mechanisms modulating the efficiency of NE repair remain unclear. Here, we showed that response to NE stress varied among different types of cancer cell lines. U251MG derived from glioblastoma exhibited severe nuclear deformation and massive DNA damage at the deformed nuclear region upon mechanical NE stress. In contrast, another cell line derived from glioblastoma, U87MG, only presented mild nuclear deformation without DNA damage. Time-lapse imaging demonstrated that repairing of ruptured NE often failed in U251MG, but not in U87MG. These differences were unlikely to have been due to weakened NE in U251MG because the expression levels of lamin A/C, determinants of the physical property of the NE, were comparable and loss of compartmentalization across the NE was observed just after laser ablation of the NE in both cell lines. U251MG proliferated more rapidly than U87MG concomitant with reduced expression of p21, a major inhibitor of cyclin-dependent kinases, suggesting a correlation between NE stress response and cell cycle progression. Indeed, visualization of cell cycle stages using fluorescent ubiquitination-based cell cycle indicator reporters revealed greater resistance of U251MG to NE stress at G1 phase than at S and G2 phases. Furthermore, attenuation of cell cycle progression by inducing p21 in U251MG counteracted the nuclear deformation and DNA damage upon NE stress. These findings imply that dysregulation of cell cycle progression in cancer cells causes loss of the NE integrity and its consequences such as DNA damage and cell death upon mechanical NE stress.
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Affiliation(s)
- Yasunao Kamikawa
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan.
| | - Zuqian Wu
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan
| | - Nayuta Nakazawa
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan
| | - Taichi Ito
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan
| | - Atsushi Saito
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan.
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22
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Barger SR, Penfield L, Bahmanyar S. Nuclear envelope assembly relies on CHMP-7 in the absence of BAF-LEM-mediated hole closure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.06.547980. [PMID: 37461528 PMCID: PMC10350047 DOI: 10.1101/2023.07.06.547980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Barrier-to-autointegration factor (BAF) is a DNA binding protein that crosslinks chromatin to assemble the nuclear envelope (NE) after mitosis. BAF also binds the Lap2b-Emerin-Man1 (LEM) domain family of NE proteins to repair interphase ruptures. The NE adaptors to ESCRTs, LEMD2-CHMP7, seal NE holes surrounding mitotic spindle microtubules (MTs), but whether NE hole closure in mitosis involves BAF-LEM binding is not known. Here, we analyze NE sealing after meiosis II in C. elegans oocytes to show that BAF-LEM binding and LEM-2 LEMD2 -CHMP-7 have distinct roles in hole closure around spindle MTs. LEM-2/EMR-1 emerin function redundantly with BAF-1 to seal the NE. Compromising BAF-LEM binding revealed an additional role for EMR-1 in maintenance of the NE permeability barrier and an essential role for LEM-2-CHMP-7 in preventing NE assembly failure. The WH domain of LEM-2 recruits the majority of CHMP-7 to the NE in C. elegans and a LEM-2 -independent pool of CHMP-7, which is mostly enriched in the nucleoplasm, also contributes to NE stability. Thus, NE hole closure surrounding spindle MTs requires redundant mechanisms that safeguard against failure in NE assembly to support embryogenesis.
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Affiliation(s)
- Sarah R. Barger
- Yale University, Department of Molecular, Cellular, Developmental Biology, 266 Whitney Ave., New Haven, CT 06511
| | - Lauren Penfield
- Current address: Department of Molecular, Cellular, and Developmental Biology at University of California, Santa Barbara, CA
| | - Shirin Bahmanyar
- Yale University, Department of Molecular, Cellular, Developmental Biology, 266 Whitney Ave., New Haven, CT 06511
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23
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Olson AT, Kang Y, Ladha AM, Lim CB, Lagunoff M, Gujral TS, Geballe AP. Polypharmacology-based kinome screen identifies new regulators of KSHV reactivation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.01.526589. [PMID: 36778430 PMCID: PMC9915688 DOI: 10.1101/2023.02.01.526589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) causes several human diseases including Kaposi's sarcoma (KS), a leading cause of cancer in Africa and in patients with AIDS. KS tumor cells harbor KSHV predominantly in a latent form, while typically <5% contain lytic replicating virus. Because both latent and lytic stages likely contribute to cancer initiation and progression, continued dissection of host regulators of this biological switch will provide insights into fundamental pathways controlling the KSHV life cycle and related disease pathogenesis. Several cellular protein kinases have been reported to promote or restrict KSHV reactivation, but our knowledge of these signaling mediators and pathways is incomplete. We employed a polypharmacology-based kinome screen to identifiy specific kinases that regulate KSHV reactivation. Those identified by the screen and validated by knockdown experiments included several kinases that enhance lytic reactivation: ERBB2 (HER2 or neu ), ERBB3 (HER3), ERBB4 (HER4), MKNK2 (MNK2), ITK, TEC, and DSTYK (RIPK5). Conversely, ERBB1 (EGFR1 or HER1), MKNK1 (MNK1) and FRK (PTK5) were found to promote the maintenance of latency. Mechanistic characterization of ERBB2 pro-lytic functions revealed a signaling connection between ERBB2 and the activation of CREB1, a transcription factor that drives KSHV lytic gene expression. These studies provided a proof-of-principle application of a polypharmacology-based kinome screen for the study of KSHV reactivation and enabled the discovery of both kinase inhibitors and specific kinases that regulate the KSHV latent-to-lytic replication switch. Author Summary Kaposi's sarcoma-associated herpesvirus (KSHV) causes Kaposi's sarcoma, a cancer particularly prevalent in Africa. In cancer cells, the virus persists in a quiescent form called latency, in which only a few viral genes are made. Periodically, the virus switches into an active replicative cycle in which most of the viral genes are made and new virus is produced. What controls the switch from latency to active replication is not well understood, but cellular kinases, enzymes that control many cellular processes, have been implicated. Using a cell culture model of KSHV reactivation along with an innovative screening method that probes the effects of many cellular kinases simultaneously, we identified drugs that significantly limit KSHV reactivation, as well as specific kinases that either enhance or restrict KSHV replicative cycle. Among these were the ERBB kinases which are known to regulate growth of cancer cells. Understanding how these and other kinases contribute to the switch leading to production of more infectious virus helps us understand the mediators and mechanisms of KSHV diseases. Additionally, because kinase inhibitors are proving to be effective for treating other diseases including some cancers, identifying ones that restrict KSHV replicative cycle may lead to new approaches to treating KSHV-related diseases.
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Affiliation(s)
- Annabel T. Olson
- Division of Human Biology, Fred Hutchinson Cancer Center, University of Washington, Seattle, WA, USA
| | - Yuqi Kang
- Division of Human Biology, Fred Hutchinson Cancer Center, University of Washington, Seattle, WA, USA
| | - Anushka M. Ladha
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Chuan Bian Lim
- Division of Human Biology, Fred Hutchinson Cancer Center, University of Washington, Seattle, WA, USA
| | - Michael Lagunoff
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Taran S. Gujral
- Division of Human Biology, Fred Hutchinson Cancer Center, University of Washington, Seattle, WA, USA
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - Adam P. Geballe
- Division of Human Biology, Fred Hutchinson Cancer Center, University of Washington, Seattle, WA, USA
- Division of Clinical Research, Fred Hutchinson Cancer Center, University of Washington, Seattle, WA, USA
- Department of Microbiology, University of Washington, Seattle, WA, USA
- Department of Medicine, University of Washington, Seattle, WA, USA
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24
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Moreno-Andrés D, Holl K, Antonin W. The second half of mitosis and its implications in cancer biology. Semin Cancer Biol 2023; 88:1-17. [PMID: 36436712 DOI: 10.1016/j.semcancer.2022.11.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 11/26/2022]
Abstract
The nucleus undergoes dramatic structural and functional changes during cell division. With the entry into mitosis, in human cells the nuclear envelope breaks down, chromosomes rearrange into rod-like structures which are collected and segregated by the spindle apparatus. While these processes in the first half of mitosis have been intensively studied, much less is known about the second half of mitosis, when a functional nucleus reforms in each of the emerging cells. Here we review our current understanding of mitotic exit and nuclear reformation with spotlights on the links to cancer biology.
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Affiliation(s)
- Daniel Moreno-Andrés
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany.
| | - Kristin Holl
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
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25
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Kono Y, Adam SA, Sato Y, Reddy KL, Zheng Y, Medalia O, Goldman RD, Kimura H, Shimi T. Nucleoplasmic lamin C rapidly accumulates at sites of nuclear envelope rupture with BAF and cGAS. J Cell Biol 2022; 221:e202201024. [PMID: 36301259 PMCID: PMC9617480 DOI: 10.1083/jcb.202201024] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 07/14/2022] [Accepted: 09/06/2022] [Indexed: 12/13/2022] Open
Abstract
In mammalian cell nuclei, the nuclear lamina (NL) underlies the nuclear envelope (NE) to maintain nuclear structure. The nuclear lamins, the major structural components of the NL, are involved in the protection against NE rupture induced by mechanical stress. However, the specific role of the lamins in repair of NE ruptures has not been fully determined. Our analyses using immunofluorescence and live-cell imaging revealed that the nucleoplasmic pool of lamin C rapidly accumulated at sites of NE rupture induced by laser microirradiation in mouse embryonic fibroblasts. The accumulation of lamin C at the rupture sites required both the immunoglobulin-like fold domain that binds to barrier-to-autointegration factor (BAF) and a nuclear localization signal. The accumulation of nuclear BAF and cytoplasmic cyclic GMP-AMP synthase (cGAS) at the rupture sites was in part dependent on lamin A/C. These results suggest that nucleoplasmic lamin C, BAF, and cGAS concertedly accumulate at sites of NE rupture for rapid repair.
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Affiliation(s)
- Yohei Kono
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Stephen A. Adam
- Department of Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Yuko Sato
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Karen L. Reddy
- Department of Biological Chemistry, Johns Hopkins University, Baltimore, MD
| | - Yixian Zheng
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Robert D. Goldman
- Department of Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Hiroshi Kimura
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
- World Research Hub Initiative, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Takeshi Shimi
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
- World Research Hub Initiative, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
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26
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Snyers L, Löhnert R, Weipoltshammer K, Schöfer C. Emerin prevents BAF-mediated aggregation of lamin A on chromosomes in telophase to allow nuclear membrane expansion and nuclear lamina formation. Mol Biol Cell 2022; 33:ar137. [PMID: 36200863 PMCID: PMC9727812 DOI: 10.1091/mbc.e22-01-0007] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Several studies have suggested a role for the LEM-domain protein emerin and the DNA binding factor BAF in nuclear envelope reformation after mitosis, but the exact molecular mechanisms are not understood. Using HeLa cells deficient for emerin or both emerin and lamin A, we show that emerin deficiency induces abnormal aggregation of lamin A at the nuclear periphery in telophase. As a result, nuclear membrane expansion is impaired and BAF accumulates at the core region, the middle part of telophase nuclei. Aggregates do not form when lamin A carries the mutation R435C in the immunoglobulin fold known to prevent interaction of lamin A with BAF suggesting that aggregation is caused by a stabilized association of lamin A with BAF bound to chromosomal DNA. Reintroduction of emerin in the cells prevents formation of lamin A clusters and BAF accumulation at the core region. Therefore emerin is required for the expansion of the nuclear membrane at the core region to enclose the nucleus and for the rapid reformation of the nuclear lamina based on lamin A/C in telophase. Finally, we show that LEM-domain and lumenal domain are required for the targeting of emerin to exert its function at the core region.
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Affiliation(s)
- L. Snyers
- Medical University of Vienna, Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Schwarzspanierstrasse 17, 1090 Vienna, Austria,*Address correspondence to: L. Snyers ()
| | - R. Löhnert
- Medical University of Vienna, Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Schwarzspanierstrasse 17, 1090 Vienna, Austria
| | - K. Weipoltshammer
- Medical University of Vienna, Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Schwarzspanierstrasse 17, 1090 Vienna, Austria
| | - C. Schöfer
- Medical University of Vienna, Center for Anatomy and Cell Biology, Division of Cell and Developmental Biology, Schwarzspanierstrasse 17, 1090 Vienna, Austria
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27
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Borah S, Dhanasekaran K, Kumar S. The LEM-ESCRT toolkit: Repair and maintenance of the nucleus. Front Cell Dev Biol 2022; 10:989217. [PMID: 36172278 PMCID: PMC9512039 DOI: 10.3389/fcell.2022.989217] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/24/2022] [Indexed: 12/04/2022] Open
Abstract
The eukaryotic genome is enclosed in a nuclear envelope that protects it from potentially damaging cellular activities and physically segregates transcription and translation.Transport across the NE is highly regulated and occurs primarily via the macromolecular nuclear pore complexes.Loss of nuclear compartmentalization due to defects in NPC function and NE integrity are tied to neurological and ageing disorders like Alzheimer’s, viral pathogenesis, immune disorders, and cancer progression.Recent work implicates inner-nuclear membrane proteins of the conserved LEM domain family and the ESCRT machinery in NE reformation during cell division and NE repair upon rupture in migrating cancer cells, and generating seals over defective NPCs. In this review, we discuss the recent in-roads made into defining the molecular mechanisms and biochemical networks engaged by LEM and many other integral inner nuclear membrane proteins to preserve the nuclear barrier.
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Affiliation(s)
- Sapan Borah
- National Institute of Immunohaematology, Mumbai, Maharashtra, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
| | - Karthigeyan Dhanasekaran
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
| | - Santosh Kumar
- National Centre for Cell Science, Pune, Maharashtra, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
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28
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Janssen A, Marcelot A, Breusegem S, Legrand P, Zinn-Justin S, Larrieu D. The BAF A12T mutation disrupts lamin A/C interaction, impairing robust repair of nuclear envelope ruptures in Nestor-Guillermo progeria syndrome cells. Nucleic Acids Res 2022; 50:9260-9278. [PMID: 36039758 PMCID: PMC9458464 DOI: 10.1093/nar/gkac726] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 08/02/2022] [Accepted: 08/12/2022] [Indexed: 12/24/2022] Open
Abstract
Nestor-Guillermo progeria syndrome (NGPS) is caused by a homozygous alanine-to-threonine mutation at position 12 (A12T) in barrier-to-autointegration factor (BAF). It is characterized by accelerated aging with severe skeletal abnormalities. BAF is an essential protein binding to DNA and nuclear envelope (NE) proteins, involved in NE rupture repair. Here, we assessed the impact of BAF A12T on NE integrity using NGPS-derived patient fibroblasts. We observed a strong defect in lamin A/C accumulation to NE ruptures in NGPS cells, restored upon homozygous reversion of the pathogenic BAF A12T mutation with CRISPR/Cas9. By combining in vitro and cellular assays, we demonstrated that while the A12T mutation does not affect BAF 3D structure and phosphorylation by VRK1, it specifically decreases the interaction between BAF and lamin A/C. Finally, we revealed that the disrupted interaction does not prevent repair of NE ruptures but instead generates weak points in the NE that lead to a higher frequency of NE re-rupturing in NGPS cells. We propose that this NE fragility could directly contribute to the premature aging phenotype in patients.
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Affiliation(s)
- Anne Janssen
- Department of Clinical Biochemistry, Cambridge Biomedical Campus, Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Agathe Marcelot
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex 91190, France
| | - Sophia Breusegem
- Department of Clinical Biochemistry, Cambridge Biomedical Campus, Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Pierre Legrand
- Synchrotron SOLEIL, HelioBio group, L’Orme des Merisiers, Gif sur-Yvette 91190, France
| | - Sophie Zinn-Justin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex 91190, France
| | - Delphine Larrieu
- Department of Clinical Biochemistry, Cambridge Biomedical Campus, Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
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29
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Kalukula Y, Stephens AD, Lammerding J, Gabriele S. Mechanics and functional consequences of nuclear deformations. Nat Rev Mol Cell Biol 2022; 23:583-602. [PMID: 35513718 PMCID: PMC9902167 DOI: 10.1038/s41580-022-00480-z] [Citation(s) in RCA: 120] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2022] [Indexed: 02/08/2023]
Abstract
As the home of cellular genetic information, the nucleus has a critical role in determining cell fate and function in response to various signals and stimuli. In addition to biochemical inputs, the nucleus is constantly exposed to intrinsic and extrinsic mechanical forces that trigger dynamic changes in nuclear structure and morphology. Emerging data suggest that the physical deformation of the nucleus modulates many cellular and nuclear functions. These functions have long been considered to be downstream of cytoplasmic signalling pathways and dictated by gene expression. In this Review, we discuss an emerging perspective on the mechanoregulation of the nucleus that considers the physical connections from chromatin to nuclear lamina and cytoskeletal filaments as a single mechanical unit. We describe key mechanisms of nuclear deformations in time and space and provide a critical review of the structural and functional adaptive responses of the nucleus to deformations. We then consider the contribution of nuclear deformations to the regulation of important cellular functions, including muscle contraction, cell migration and human disease pathogenesis. Collectively, these emerging insights shed new light on the dynamics of nuclear deformations and their roles in cellular mechanobiology.
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Affiliation(s)
- Yohalie Kalukula
- University of Mons, Soft Matter and Biomaterials group, Interfaces and Complex Fluids Laboratory, Research Institute for Biosciences, CIRMAP, Place du Parc, 20 B-7000 Mons, Belgium
| | - Andrew D. Stephens
- Biology Department, University of Massachusetts Amherst, Amherst, MA, USA
| | - Jan Lammerding
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA,Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Sylvain Gabriele
- University of Mons, Soft Matter and Biomaterials group, Interfaces and Complex Fluids Laboratory, Research Institute for Biosciences, CIRMAP, Place du Parc, 20 B-7000 Mons, Belgium
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30
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Prissette M, Fury W, Koss M, Racioppi C, Fedorova D, Dragileva E, Clarke G, Pohl T, Dugan J, Ahrens D, Chiu J, Hunt C, Siao CJ, Young T, Bhowmick A, Rogulin V, Desclaux M, Hayden EY, Podgorski M, Gao M, Macdonald LE, Frendewey D, Yancopoulos GD, Zambrowicz B. Disruption of nuclear envelope integrity as a possible initiating event in tauopathies. Cell Rep 2022; 40:111249. [PMID: 36001963 DOI: 10.1016/j.celrep.2022.111249] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 06/23/2022] [Accepted: 07/29/2022] [Indexed: 11/03/2022] Open
Abstract
The microtubule-associated protein tau is an abundant component of neurons of the central nervous system. In Alzheimer's disease and other neurodegenerative tauopathies, tau is found hyperphosphorylated and aggregated in neurofibrillary tangles. To obtain a better understanding of the cellular perturbations that initiate tau pathogenesis, we performed a CRISPR-Cas9 screen for genetic modifiers that enhance tau aggregation. This initial screen yielded three genes, BANF1, ANKLE2, and PPP2CA, whose inactivation promotes the accumulation of tau in a phosphorylated and insoluble form. In a complementary screen, we identified three additional genes, LEMD2, LEMD3, and CHMP7, that, when overexpressed, provide protection against tau aggregation. The proteins encoded by the identified genes are mechanistically linked and recognized for their roles in the maintenance and repair of the nuclear envelope. These results implicate the disruption of nuclear envelope integrity as a possible initiating event in tauopathies and reveal targets for therapeutic intervention.
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Affiliation(s)
| | - Wen Fury
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | | | | | | | | | | | - Taylor Pohl
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | - John Dugan
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | | | - Joyce Chiu
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | | | | | - Tara Young
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | | | | | | | | | | | - Min Gao
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
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31
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Katiyar A, Zhang J, Antani JD, Yu Y, Scott KL, Lele PP, Reinhart‐King CA, Sniadecki NJ, Roux KJ, Dickinson RB, Lele TP. The Nucleus Bypasses Obstacles by Deforming Like a Drop with Surface Tension Mediated by Lamin A/C. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2201248. [PMID: 35712768 PMCID: PMC9376816 DOI: 10.1002/advs.202201248] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 05/20/2022] [Indexed: 06/15/2023]
Abstract
Migrating cells must deform their stiff cell nucleus to move through pores and fibers in tissue. Lamin A/C is known to hinder cell migration by limiting nuclear deformation and passage through confining channels, but its role in nuclear deformation and passage through fibrous environments is less clear. Cell and nuclear migration through discrete, closely spaced, slender obstacles which mimic the mechanical properties of collagen fibers are studied. Nuclei bypass slender obstacles while preserving their overall morphology by deforming around them with deep local invaginations of little resisting force. The obstacles do not impede the nuclear trajectory and do not cause rupture of the nuclear envelope. Nuclei likewise deform around single collagen fibers in cells migrating in 3D collagen gels. In contrast to its limiting role in nuclear passage through confining channels, lamin A/C facilitates nuclear deformation and passage through fibrous environments; nuclei in lamin-null (Lmna-/- ) cells lose their overall morphology and become entangled on the obstacles. Analogous to surface tension-mediated deformation of a liquid drop, lamin A/C imparts a surface tension on the nucleus that allows nuclear invaginations with little mechanical resistance, preventing nuclear entanglement and allowing nuclear passage through fibrous environments.
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Affiliation(s)
- Aditya Katiyar
- Department of Biomedical EngineeringTexas A&M University101 Bizzell St.College StationTX77843USA
| | - Jian Zhang
- Department of Biomedical EngineeringVanderbilt University2301 Vanderbilt PlaceNashvilleTN37235USA
| | - Jyot D. Antani
- Artie McFerrin Department of Chemical EngineeringTexas A&M University3122 TAMUCollege StationTX77843USA
| | - Yifan Yu
- Department of Chemical EngineeringUniversity of Florida1030 Center DriveGainesvilleFL32611USA
| | - Kelsey L. Scott
- Enabling Technologies GroupSanford Research2301 East 60th St NSioux FallsSD57104USA
| | - Pushkar P. Lele
- Artie McFerrin Department of Chemical EngineeringTexas A&M University3122 TAMUCollege StationTX77843USA
| | - Cynthia A. Reinhart‐King
- Department of Biomedical EngineeringVanderbilt University2301 Vanderbilt PlaceNashvilleTN37235USA
| | - Nathan J. Sniadecki
- Department of Mechanical EngineeringDepartment of Lab Medicine and PathologyInstitute for Stem Cell and Regenerative MedicineCenter for Cardiac BiologyUniversity of WashingtonStevens Way, Box 352600SeattleWA98195USA
| | - Kyle J. Roux
- Enabling Technologies GroupSanford Research2301 East 60th St NSioux FallsSD57104USA
- Department of PediatricsSanford School of MedicineUniversity of South Dakota414 E Clark StVermillionSD57069USA
| | - Richard B. Dickinson
- Department of Chemical EngineeringUniversity of Florida1030 Center DriveGainesvilleFL32611USA
| | - Tanmay P. Lele
- Department of Biomedical EngineeringTexas A&M University101 Bizzell St.College StationTX77843USA
- Artie McFerrin Department of Chemical EngineeringTexas A&M University3122 TAMUCollege StationTX77843USA
- Department of Translational Medical SciencesTexas A&M University2121 W Holcombe St.HoustonTX77030USA
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32
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Kamikawa Y, Saito A, Imaizumi K. Impact of Nuclear Envelope Stress on Physiological and Pathological Processes in Central Nervous System. Neurochem Res 2022; 47:2478-2487. [PMID: 35486254 DOI: 10.1007/s11064-022-03608-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 04/07/2022] [Accepted: 04/12/2022] [Indexed: 01/10/2023]
Abstract
The nuclear envelope (NE) separates genomic DNA from the cytoplasm and provides the molecular platforms for nucleocytoplasmic transport, higher-order chromatin organization, and physical links between the nucleus and cytoskeleton. Recent studies have shown that the NE is often damaged by various stresses termed "NE stress", leading to critical cellular dysfunction. Accumulating evidence has revealed the crucial roles of NE stress in the pathology of a broad spectrum of diseases. In the central nervous system (CNS), NE dysfunction impairs neural development and is associated with several neurological disorders, such as Alzheimer's disease and autosomal dominant leukodystrophy. In this review, the structure and functions of the NE are summarized, and the concepts of NE stress and NE stress responses are introduced. Additionally, the significant roles of the NE in the development of CNS and the mechanistic connections between NE stress and neurological disorders are described.
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Affiliation(s)
- Yasunao Kamikawa
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan.
| | - Atsushi Saito
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan.
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33
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Mechanisms of A-Type Lamin Targeting to Nuclear Ruptures Are Disrupted in LMNA- and BANF1-Associated Progerias. Cells 2022; 11:cells11050865. [PMID: 35269487 PMCID: PMC8909658 DOI: 10.3390/cells11050865] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/23/2022] [Accepted: 02/28/2022] [Indexed: 02/04/2023] Open
Abstract
Mutations in the genes LMNA and BANF1 can lead to accelerated aging syndromes called progeria. The protein products of these genes, A-type lamins and BAF, respectively, are nuclear envelope (NE) proteins that interact and participate in various cellular processes, including nuclear envelope rupture and repair. BAF localizes to sites of nuclear rupture and recruits NE-repair machinery, including the LEM-domain proteins, ESCRT-III complex, A-type lamins, and membranes. Here, we show that it is a mobile, nucleoplasmic population of A-type lamins that is rapidly recruited to ruptures in a BAF-dependent manner via BAF’s association with the Ig-like β fold domain of A-type lamins. These initially mobile lamins become progressively stabilized at the site of rupture. Farnesylated prelamin A and lamin B1 fail to localize to nuclear ruptures, unless that farnesylation is inhibited. Progeria-associated LMNA mutations inhibit the recruitment affected A-type lamin to nuclear ruptures, due to either permanent farnesylation or inhibition of BAF binding. A progeria-associated BAF mutant targets to nuclear ruptures but is unable to recruit A-type lamins. Together, these data reveal the mechanisms that determine how lamins respond to nuclear ruptures and how progeric mutations of LMNA and BANF1 impair recruitment of A-type lamins to nuclear ruptures.
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Mammel AE, Hatch EM. Genome instability from nuclear catastrophe and DNA damage. Semin Cell Dev Biol 2022; 123:131-139. [PMID: 33839019 PMCID: PMC8494860 DOI: 10.1016/j.semcdb.2021.03.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/29/2021] [Indexed: 11/28/2022]
Abstract
The nuclear envelope compartmentalizes the eukaryotic genome, provides mechanical resistance, and regulates access to the chromatin. However, recent studies have identified several conditions where the nuclear membrane ruptures during interphase, breaking down this compartmentalization leading to DNA damage, chromothripsis, and kataegis. This review discusses three major circumstances that promote nuclear membrane rupture, nuclear deformation, chromatin bridges, and micronucleation, and how each of these nuclear catastrophes results in DNA damage. In addition, we highlight recent studies that demonstrate a single chromosome missegregation can initiate a cascade of events that lead to accumulating damage and even multiple rounds of chromothripsis.
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Affiliation(s)
- Anna E. Mammel
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Emily M. Hatch
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA,Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
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35
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Kamikawa Y, Imaizumi K. Advances in understanding the mechanisms of repairing damaged nuclear envelop. J Biochem 2022; 171:609-617. [PMID: 35134968 DOI: 10.1093/jb/mvac012] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 01/26/2022] [Indexed: 11/12/2022] Open
Abstract
The nuclear envelope (NE) separates genomic DNA from the cytoplasm in eukaryotes. The structure of the NE is dynamically altered not only in mitotic disassembly and reassembly but also during interphase. Recent studies have shown that the NE is frequently damaged by various cellular stresses that degenerate NE components and/or disrupt their functional interactions. These stresses are referred to as "NE stress." Accumulating evidence has demonstrated that NE stress potentially causes severe cellular dysfunctions, such as cell death and genome instability. In this review, the concept of NE stress, the processes repairing damage of the NE caused by NE stress, and the molecular mechanisms by which NE stress contributes to disease pathogenesis are introduced.
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Affiliation(s)
- Yasunao Kamikawa
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan
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36
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Janssen AFJ, Breusegem SY, Larrieu D. Current Methods and Pipelines for Image-Based Quantitation of Nuclear Shape and Nuclear Envelope Abnormalities. Cells 2022; 11:347. [PMID: 35159153 PMCID: PMC8834579 DOI: 10.3390/cells11030347] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 02/02/2023] Open
Abstract
Any given cell type has an associated "normal" nuclear morphology, which is important to maintain proper cellular functioning and safeguard genomic integrity. Deviations from this can be indicative of diseases such as cancer or premature aging syndrome. To accurately assess nuclear abnormalities, it is important to use quantitative measures of nuclear morphology. Here, we give an overview of several nuclear abnormalities, including micronuclei, nuclear envelope invaginations, blebs and ruptures, and review the current methods used for image-based quantification of these abnormalities. We discuss several parameters that can be used to quantify nuclear shape and compare their outputs using example images. In addition, we present new pipelines for quantitative analysis of nuclear blebs and invaginations. Quantitative analyses of nuclear aberrations and shape will be important in a wide range of applications, from assessments of cancer cell anomalies to studies of nucleus deformability under mechanical or other types of stress.
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Affiliation(s)
| | | | - Delphine Larrieu
- Department of Clinical Biochemistry, Addenbrookes Biomedical Campus, Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK; (A.F.J.J.); (S.Y.B.)
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Shankar R, Lettman MM, Whisler W, Frankel EB, Audhya A. The ESCRT machinery directs quality control over inner nuclear membrane architecture. Cell Rep 2022; 38:110263. [PMID: 35045304 PMCID: PMC8801257 DOI: 10.1016/j.celrep.2021.110263] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 11/21/2021] [Accepted: 12/21/2021] [Indexed: 11/20/2022] Open
Abstract
The late-acting endosomal sorting complex required for transport (ESCRT) machinery has been implicated in facilitating the resealing of the nuclear envelope (NE) after mitosis, enabling compartmentalization of the genome away from the cytoplasm. Here, we leverage the stereotypic first division of the C. elegans embryo to identify additional functions of the ESCRT machinery in maintaining the structure of the inner nuclear membrane. Specifically, impaired ESCRT function results in a defect in the pruning of inner nuclear membrane invaginations, which arise normally during NE reformation and expansion. Additionally, in combination with a hypomorphic mutation that interferes with assembly of the underlying nuclear lamina, inhibition of ESCRT function significantly perturbs NE architecture and increases chromosome segregation defects, resulting in penetrant embryonic lethality. Our findings highlight links between ESCRT-mediated inner nuclear membrane remodeling, maintenance of nuclear envelope morphology, and the preservation of the genome during early development. In this study, Shankar et al. demonstrate that defects in ESCRT machinery functions impair pruning of inner nuclear membrane invaginations that form normally after mitotic exit as the nuclear envelope undergoes expansion. These findings highlight a critical role for the ESCRT machinery in the maintenance of inner nuclear membrane morphology.
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Affiliation(s)
- Raakhee Shankar
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Molly M Lettman
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - William Whisler
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Elisa B Frankel
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA.
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38
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Coupling lipid synthesis with nuclear envelope remodeling. Trends Biochem Sci 2022; 47:52-65. [PMID: 34556392 PMCID: PMC9943564 DOI: 10.1016/j.tibs.2021.08.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/12/2021] [Accepted: 08/25/2021] [Indexed: 01/10/2023]
Abstract
The nuclear envelope (NE) is a protective barrier to the genome, yet its membranes undergo highly dynamic remodeling processes that are necessary for cell growth and maintenance. While mechanisms by which proteins promote NE remodeling are emerging, the types of bilayer lipids and the lipid-protein interactions that define and sculpt nuclear membranes remain elusive. The NE is continuous with the endoplasmic reticulum (ER) and recent evidence suggests that lipids produced in the ER are harnessed to remodel nuclear membranes. In this review, we examine new roles for lipid species made proximally within the ER and locally at the NE to control NE dynamics. We further explore how the biosynthesis of lipids coordinates NE remodeling to ensure genome protection.
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Wallis SS, Ventimiglia LN, Otigbah E, Infante E, Cuesta-Geijo MA, Kidiyoor GR, Carbajal MA, Fleck RA, Foiani M, Garcia-Manyes S, Martin-Serrano J, Agromayor M. The ESCRT machinery counteracts Nesprin-2G-mediated mechanical forces during nuclear envelope repair. Dev Cell 2021; 56:3192-3202.e8. [PMID: 34818527 PMCID: PMC8657813 DOI: 10.1016/j.devcel.2021.10.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/03/2021] [Accepted: 10/28/2021] [Indexed: 12/31/2022]
Abstract
Transient nuclear envelope ruptures during interphase (NERDI) occur due to cytoskeletal compressive forces at sites of weakened lamina, and delayed NERDI repair results in genomic instability. Nuclear envelope (NE) sealing is completed by endosomal sorting complex required for transport (ESCRT) machinery. A key unanswered question is how local compressive forces are counteracted to allow efficient membrane resealing. Here, we identify the ESCRT-associated protein BROX as a crucial factor required to accelerate repair of the NE. Critically, BROX binds Nesprin-2G, a component of the linker of nucleoskeleton and cytoskeleton complex (LINC). This interaction promotes Nesprin-2G ubiquitination and facilitates the relaxation of mechanical stress imposed by compressive actin fibers at the rupture site. Thus, BROX rebalances excessive cytoskeletal forces in cells experiencing NE instability to promote effective NERDI repair. Our results demonstrate that BROX coordinates mechanoregulation with membrane remodeling to ensure the maintenance of nuclear-cytoplasmic compartmentalization and genomic stability. Cytoskeletal forces exerted on the nucleus can rupture its membrane BROX is recruited to sites of rupture by the ESCRT membrane remodeling machinery BROX ubiquitinates the LINC complex protein Nesprin-2G, targeting it for degradation BROX coordinates local relaxation of mechanical stress with membrane remodeling
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Affiliation(s)
- Samuel S Wallis
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London SE1 9RT, UK
| | - Leandro N Ventimiglia
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London SE1 9RT, UK
| | - Evita Otigbah
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London SE1 9RT, UK
| | - Elvira Infante
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, and London Centre for Nanotechnology, King's College London, London WC2R 2LS, UK
| | - Miguel Angel Cuesta-Geijo
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London SE1 9RT, UK; Centro Nacional Instituto de Investigación y Tecnología Agraria y Alimentaria (CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain
| | - Gururaj Rao Kidiyoor
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy; Università degli Studi di Milano, 20122 Milan, Italy
| | | | - Roland A Fleck
- Centre for Ultrastructural Imaging, King's College London, London SE1 1UL, UK
| | - Marco Foiani
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy; Università degli Studi di Milano, 20122 Milan, Italy
| | - Sergi Garcia-Manyes
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, and London Centre for Nanotechnology, King's College London, London WC2R 2LS, UK; the Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Juan Martin-Serrano
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London SE1 9RT, UK.
| | - Monica Agromayor
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London SE1 9RT, UK.
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Napoletano F, Ferrari Bravo G, Voto IAP, Santin A, Celora L, Campaner E, Dezi C, Bertossi A, Valentino E, Santorsola M, Rustighi A, Fajner V, Maspero E, Ansaloni F, Cancila V, Valenti CF, Santo M, Artimagnella OB, Finaurini S, Gioia U, Polo S, Sanges R, Tripodo C, Mallamaci A, Gustincich S, d'Adda di Fagagna F, Mantovani F, Specchia V, Del Sal G. The prolyl-isomerase PIN1 is essential for nuclear Lamin-B structure and function and protects heterochromatin under mechanical stress. Cell Rep 2021; 36:109694. [PMID: 34525372 DOI: 10.1016/j.celrep.2021.109694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 06/29/2021] [Accepted: 08/19/2021] [Indexed: 01/24/2023] Open
Abstract
Chromatin organization plays a crucial role in tissue homeostasis. Heterochromatin relaxation and consequent unscheduled mobilization of transposable elements (TEs) are emerging as key contributors of aging and aging-related pathologies, including Alzheimer's disease (AD) and cancer. However, the mechanisms governing heterochromatin maintenance or its relaxation in pathological conditions remain poorly understood. Here we show that PIN1, the only phosphorylation-specific cis/trans prolyl isomerase, whose loss is associated with premature aging and AD, is essential to preserve heterochromatin. We demonstrate that this PIN1 function is conserved from Drosophila to humans and prevents TE mobilization-dependent neurodegeneration and cognitive defects. Mechanistically, PIN1 maintains nuclear type-B Lamin structure and anchoring function for heterochromatin protein 1α (HP1α). This mechanism prevents nuclear envelope alterations and heterochromatin relaxation under mechanical stress, which is a key contributor to aging-related pathologies.
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Affiliation(s)
- Francesco Napoletano
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy.
| | - Gloria Ferrari Bravo
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Ilaria Anna Pia Voto
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Aurora Santin
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Lucia Celora
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Elena Campaner
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Clara Dezi
- Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Arianna Bertossi
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Elena Valentino
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Mariangela Santorsola
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Alessandra Rustighi
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | | | - Elena Maspero
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy
| | - Federico Ansaloni
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Valeria Cancila
- Tumor Immunology Unit, Department of Health Science, Human Pathology Section, School of Medicine, University of Palermo, 90133 Palermo, Italy
| | - Cesare Fabio Valenti
- Tumor Immunology Unit, Department of Health Science, Human Pathology Section, School of Medicine, University of Palermo, 90133 Palermo, Italy
| | - Manuela Santo
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | | | - Sara Finaurini
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Ubaldo Gioia
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy
| | - Simona Polo
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy
| | - Remo Sanges
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Claudio Tripodo
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy; Tumor Immunology Unit, Department of Health Science, Human Pathology Section, School of Medicine, University of Palermo, 90133 Palermo, Italy
| | - Antonello Mallamaci
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Stefano Gustincich
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy; Central RNA Laboratory, Italian Institute of Technology, 16163 Genova, Italy
| | - Fabrizio d'Adda di Fagagna
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy; Institute of Molecular Genetics, National Research Institute (CNR), Pavia, Italy
| | - Fiamma Mantovani
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Valeria Specchia
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, 73100 Lecce, Italy
| | - Giannino Del Sal
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy; FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy.
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41
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Kutay U, Jühlen R, Antonin W. Mitotic disassembly and reassembly of nuclear pore complexes. Trends Cell Biol 2021; 31:1019-1033. [PMID: 34294532 DOI: 10.1016/j.tcb.2021.06.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/28/2021] [Accepted: 06/28/2021] [Indexed: 12/19/2022]
Abstract
Nuclear pore complexes (NPCs) are huge protein assemblies within the nuclear envelope (NE) that serve as selective gates for macromolecular transport between nucleus and cytoplasm. When higher eukaryotic cells prepare for division, they rapidly disintegrate NPCs during NE breakdown such that nuclear and cytoplasmic components mix to enable the formation of a cytoplasmic mitotic spindle. At the end of mitosis, reassembly of NPCs is coordinated with the establishment of the NE around decondensing chromatin. We review recent progress on mitotic NPC disassembly and reassembly, focusing on vertebrate cells. We highlight novel mechanistic insights into how NPCs are rapidly disintegrated into conveniently reusable building blocks, and put divergent models of (post-)mitotic NPC assembly into a spatial and temporal context.
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Affiliation(s)
- Ulrike Kutay
- Institute of Biochemistry, Department of Biology, Eidgenössische Technische Hochschule (ETH) Zurich, Otto-Stern-Weg 3, 8093 Zurich, Switzerland.
| | - Ramona Jühlen
- Institute of Biochemistry and Molecular Cell Biology, Medical School, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany.
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42
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Kamikawa Y, Saito A, Matsuhisa K, Kaneko M, Asada R, Horikoshi Y, Tashiro S, Imaizumi K. OASIS/CREB3L1 is a factor that responds to nuclear envelope stress. Cell Death Discov 2021; 7:152. [PMID: 34226518 PMCID: PMC8257603 DOI: 10.1038/s41420-021-00540-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/30/2021] [Accepted: 05/29/2021] [Indexed: 11/09/2022] Open
Abstract
The nuclear envelope (NE) safeguards the genome and is pivotal for regulating genome activity as the structural scaffold of higher-order chromatin organization. NE had been thought as the stable during the interphase of cell cycle. However, recent studies have revealed that the NE can be damaged by various stresses such as mechanical stress and cellular senescence. These types of stresses are called NE stress. It has been proposed that NE stress is closely related to cellular dysfunctions such as genome instability and cell death. Here, we found that an endoplasmic reticulum (ER)-resident transmembrane transcription factor, OASIS, accumulates at damaged NE. Notably, the major components of nuclear lamina, Lamin proteins were depleted at the NE where OASIS accumulates. We previously demonstrated that OASIS is cleaved at the membrane domain in response to ER stress. In contrast, OASIS accumulates as the full-length form to damaged NE in response to NE stress. The accumulation to damaged NE is specific for OASIS among OASIS family members. Intriguingly, OASIS colocalizes with the components of linker of nucleoskeleton and cytoskeleton complexes, SUN2 and Nesprin-2 at the damaged NE. OASIS partially colocalizes with BAF, LEM domain proteins, and a component of ESCRT III, which are involved in the repair of ruptured NE. Furthermore, OASIS suppresses DNA damage induced by NE stress and restores nuclear deformation under NE stress conditions. Our findings reveal a novel NE stress response pathway mediated by OASIS.
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Affiliation(s)
- Yasunao Kamikawa
- Department of Stress Protein Processing, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.,Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Atsushi Saito
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Koji Matsuhisa
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Masayuki Kaneko
- Department of Pharmacology and Therapeutic Innovation, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Rie Asada
- Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Yasunori Horikoshi
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Satoshi Tashiro
- Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.
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43
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Wischnewski M, Ablasser A. Interplay of cGAS with chromatin. Trends Biochem Sci 2021; 46:822-831. [PMID: 34215510 DOI: 10.1016/j.tibs.2021.05.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/21/2021] [Accepted: 05/31/2021] [Indexed: 01/07/2023]
Abstract
Recognition of DNA is an evolutionarily highly conserved mechanism of immunity. In mammals, the cGAS-STING pathway plays a central role in coupling DNA sensing to the execution of innate immune mechanisms, both in contexts of infection as well as in noninfectious settings of cellular stress and injury. The indiscriminate ability of double-stranded DNA (dsDNA) to activate cGAS challenges our understanding on how engagement of this pathway is prevented on genomic self-DNA under homeostatic conditions. Here, we review recent discoveries on the regulation of cGAS on chromatin and we discuss implications for cGAS-dependent inflammatory phenotypes. We close by highlighting emerging developments on the role of nuclear cGAS and related open questions for future research.
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Affiliation(s)
- Marilena Wischnewski
- Global Health Institute, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Andrea Ablasser
- Global Health Institute, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland.
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44
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Chen NY, Kim PH, Tu Y, Yang Y, Heizer PJ, Young SG, Fong LG. Increased expression of LAP2β eliminates nuclear membrane ruptures in nuclear lamin-deficient neurons and fibroblasts. Proc Natl Acad Sci U S A 2021; 118:e2107770118. [PMID: 34161290 PMCID: PMC8237679 DOI: 10.1073/pnas.2107770118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Defects or deficiencies in nuclear lamins cause pathology in many cell types, and recent studies have implicated nuclear membrane (NM) ruptures as a cause of cell toxicity. We previously observed NM ruptures and progressive cell death in the developing brain of lamin B1-deficient mouse embryos. We also observed frequent NM ruptures and DNA damage in nuclear lamin-deficient fibroblasts. Factors modulating susceptibility to NM ruptures remain unclear, but we noted low levels of LAP2β, a chromatin-binding inner NM protein, in fibroblasts with NM ruptures. Here, we explored the apparent link between LAP2β and NM ruptures in nuclear lamin-deficient neurons and fibroblasts, and we tested whether manipulating LAP2β expression levels would alter NM rupture frequency. In cortical plate neurons of lamin B1-deficient embryos, we observed a strong correlation between low LAP2β levels and NM ruptures. We also found low LAP2β levels and frequent NM ruptures in neurons of cultured Lmnb1-/- neurospheres. Reducing LAP2β expression in Lmnb1-/- neurons with an siRNA markedly increased the NM rupture frequency (without affecting NM rupture duration), whereas increased LAP2β expression eliminated NM ruptures and reduced DNA damage. Consistent findings were observed in nuclear lamin-deficient fibroblasts. Reduced LAP2β expression increased NM ruptures, whereas increased LAP2β expression virtually abolished NM ruptures. Increased LAP2β expression nearly abolished NM ruptures in cells subjected to mechanical stress (an intervention that increases NM ruptures). Our studies showed that increasing LAP2β expression bolsters NM integrity in nuclear lamin-deficient cells and markedly reduces NM rupture frequency.
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Affiliation(s)
- Natalie Y Chen
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Paul H Kim
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Yiping Tu
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Ye Yang
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Patrick J Heizer
- Department of Medicine, University of California, Los Angeles, CA 90095
| | - Stephen G Young
- Department of Medicine, University of California, Los Angeles, CA 90095;
- Department of Human Genetics, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
| | - Loren G Fong
- Department of Medicine, University of California, Los Angeles, CA 90095;
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45
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Marcelot A, Petitalot A, Ropars V, Le Du MH, Samson C, Dubois S, Hoffmann G, Miron S, Cuniasse P, Marquez JA, Thai R, Theillet FX, Zinn-Justin S. Di-phosphorylated BAF shows altered structural dynamics and binding to DNA, but interacts with its nuclear envelope partners. Nucleic Acids Res 2021; 49:3841-3855. [PMID: 33744941 PMCID: PMC8053085 DOI: 10.1093/nar/gkab184] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 02/05/2021] [Accepted: 03/06/2021] [Indexed: 02/07/2023] Open
Abstract
Barrier-to-autointegration factor (BAF), encoded by the BANF1 gene, is an abundant and ubiquitously expressed metazoan protein that has multiple functions during the cell cycle. Through its ability to cross-bridge two double-stranded DNA (dsDNA), it favours chromosome compaction, participates in post-mitotic nuclear envelope reassembly and is essential for the repair of large nuclear ruptures. BAF forms a ternary complex with the nuclear envelope proteins lamin A/C and emerin, and its interaction with lamin A/C is defective in patients with recessive accelerated aging syndromes. Phosphorylation of BAF by the vaccinia-related kinase 1 (VRK1) is a key regulator of BAF localization and function. Here, we demonstrate that VRK1 successively phosphorylates BAF on Ser4 and Thr3. The crystal structures of BAF before and after phosphorylation are extremely similar. However, in solution, the extensive flexibility of the N-terminal helix α1 and loop α1α2 in BAF is strongly reduced in di-phosphorylated BAF, due to interactions between the phosphorylated residues and the positively charged C-terminal helix α6. These regions are involved in DNA and lamin A/C binding. Consistently, phosphorylation causes a 5000-fold loss of affinity for dsDNA. However, it does not impair binding to lamin A/C Igfold domain and emerin nucleoplasmic region, which leaves open the question of the regulation of these interactions.
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Affiliation(s)
- Agathe Marcelot
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Ambre Petitalot
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Virginie Ropars
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Marie-Hélène Le Du
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Camille Samson
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | | | - Guillaume Hoffmann
- High Throughput Crystallization Lab, EMBL Grenoble Outstation, Grenoble Cedex, France
| | - Simona Miron
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Philippe Cuniasse
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Jose Antonio Marquez
- High Throughput Crystallization Lab, EMBL Grenoble Outstation, Grenoble Cedex, France
| | | | - François-Xavier Theillet
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Sophie Zinn-Justin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
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46
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Abstract
Micronuclei are aberrant nuclear compartments that form when chromosomes or chromosome fragments fail to incorporate into a primary nucleus during mitotic exit. Ruptures at the micronuclear envelope are associated with DNA damage and activation of immune sensing pathways. To gain insights into these processes, we have developed a method to purify ruptured micronuclei. This method paves the way toward understanding the consequences of micronuclear envelope rupture. For complete details on the use and execution of this protocol, please refer to Mohr et al. (2021). An optimized protocol for purifying micronuclei with ruptured nuclear envelopes Use of fluorescent markers enables flow sorting of distinct populations of micronuclei Preservation of micronuclear protein and DNA content for functional characterization
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Affiliation(s)
| | - John Maciejowski
- Molecular Biology Program, Sloan Kettering Institute, New York, NY 10065, USA
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47
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Halfmann CT, Roux KJ. Barrier-to-autointegration factor: a first responder for repair of nuclear ruptures. Cell Cycle 2021; 20:647-660. [PMID: 33678126 DOI: 10.1080/15384101.2021.1892320] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
The nuclear envelope (NE) is a critical barrier between the cytosol and nucleus that is key for compartmentalization within the cell and serves an essential role in organizing and protecting genomic DNA. Rupturing of the NE through loss of constitutive NE proteins and/or mechanical force applied to the nucleus results in the unregulated mixing of cytosolic and nuclear compartments, leading to DNA damage and genomic instability. Nuclear rupture has recently gained interest as a mechanism that may participate in various NE-associated diseases as well as cancer. Remarkably, these rupturing events are often transient, with cells being capable of rapidly repairing nuclear ruptures. Recently, we identified Barrier-to-Autointegration Factor (BAF), a DNA-binding protein involved in post-mitotic NE reformation and cytosolic viral regulation, as an essential protein for nuclear rupture repair. During interphase, the highly mobile cytosolic BAF is primed to monitor for a compromised NE by rapidly binding to newly exposed nuclear DNA and subsequently recruiting the factors necessary for NE repair. This review highlights the recent findings of BAF's roles in rupture repair, and offers perspectives on how regulatory factors that control BAF activity may potentially alter the cellular response to nuclear ruptures and how BAF may participate in human disease.
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Affiliation(s)
| | - Kyle J Roux
- Enabling Technologies Group, Sanford Research, Sioux Falls, SD, USA.,Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
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48
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Zhen Y, Radulovic M, Vietri M, Stenmark H. Sealing holes in cellular membranes. EMBO J 2021; 40:e106922. [PMID: 33644904 PMCID: PMC8013788 DOI: 10.15252/embj.2020106922] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/29/2020] [Accepted: 11/04/2020] [Indexed: 12/11/2022] Open
Abstract
The compartmentalization of eukaryotic cells, which is essential for their viability and functions, is ensured by single or double bilayer membranes that separate the cell from the exterior and form boundaries between the cell’s organelles and the cytosol. Nascent nuclear envelopes and autophagosomes, which both are enveloped by double membranes, need to be sealed during the late stage of their biogenesis. On the other hand, the integrity of cellular membranes such as the plasma membrane, lysosomes and the nuclear envelope can be compromised by pathogens, chemicals, radiation, inflammatory responses and mechanical stress. There are cellular programmes that restore membrane integrity after injury. Here, we review cellular mechanisms that have evolved to maintain membrane integrity during organelle biogenesis and after injury, including membrane scission mediated by the endosomal sorting complex required for transport (ESCRT), vesicle patching and endocytosis.
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Affiliation(s)
- Yan Zhen
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Maja Radulovic
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Marina Vietri
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Harald Stenmark
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Faculty of Medicine and Health Sciences, Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway
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49
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Mohr L, Toufektchan E, von Morgen P, Chu K, Kapoor A, Maciejowski J. ER-directed TREX1 limits cGAS activation at micronuclei. Mol Cell 2021; 81:724-738.e9. [PMID: 33476576 PMCID: PMC7897315 DOI: 10.1016/j.molcel.2020.12.037] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 11/18/2020] [Accepted: 12/18/2020] [Indexed: 02/06/2023]
Abstract
Micronuclei are aberrant nuclear compartments that can form as a result of chromosome mis-segregation. Frequent loss of micronuclear envelope integrity exposes DNA to the cytoplasm, leading to chromosome fragmentation and immune activation. Here, we use micronuclei purification to show that the endoplasmic reticulum (ER)-associated nuclease TREX1 inhibits cGAS activation at micronuclei by degrading micronuclear DNA upon micronuclear envelope rupture. We demonstrate that the ER accesses ruptured micronuclei and plays a critical role in enabling TREX1 nucleolytic attack. TREX1 mutations, previously implicated in immune disease, untether TREX1 from the ER, disrupt TREX1 localization to micronuclei, diminish micronuclear DNA damage, and enhance cGAS activation. These results establish ER-directed resection of micronuclear DNA by TREX1 as a critical regulator of cytosolic DNA sensing in chromosomally unstable cells and provide a mechanistic basis for the importance of TREX1 ER tethering in preventing autoimmunity.
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Affiliation(s)
- Lisa Mohr
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Eléonore Toufektchan
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Patrick von Morgen
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Kevan Chu
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Aakanksha Kapoor
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - John Maciejowski
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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50
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Burla R, La Torre M, Maccaroni K, Verni F, Giunta S, Saggio I. Interplay of the nuclear envelope with chromatin in physiology and pathology. Nucleus 2020; 11:205-218. [PMID: 32835589 PMCID: PMC7529417 DOI: 10.1080/19491034.2020.1806661] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 12/21/2022] Open
Abstract
The nuclear envelope compartmentalizes chromatin in eukaryotic cells. The main nuclear envelope components are lamins that associate with a panoply of factors, including the LEM domain proteins. The nuclear envelope of mammalian cells opens up during cell division. It is reassembled and associated with chromatin at the end of mitosis when telomeres tether to the nuclear periphery. Lamins, LEM domain proteins, and DNA binding factors, as BAF, contribute to the reorganization of chromatin. In this context, an emerging role is that of the ESCRT complex, a machinery operating in multiple membrane assembly pathways, including nuclear envelope reformation. Research in this area is unraveling how, mechanistically, ESCRTs link to nuclear envelope associated factors as LEM domain proteins. Importantly, ESCRTs work also during interphase for repairing nuclear envelope ruptures. Altogether the advances in this field are giving new clues for the interpretation of diseases implicating nuclear envelope fragility, as laminopathies and cancer. ABBREVIATIONS na, not analyzed; ko, knockout; kd, knockdown; NE, nuclear envelope; LEM, LAP2-emerin-MAN1 (LEM)-domain containing proteins; LINC, linker of nucleoskeleton and cytoskeleton complexes; Cyt, cytoplasm; Chr, chromatin; MB, midbody; End, endosomes; Tel, telomeres; INM, inner nuclear membrane; NP, nucleoplasm; NPC, Nuclear Pore Complex; ER, Endoplasmic Reticulum; SPB, spindle pole body.
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Affiliation(s)
- Romina Burla
- Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
- CNR Institute of Molecular Biology and Pathology, Italy
| | - Mattia La Torre
- Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
| | - Klizia Maccaroni
- Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
| | - Fiammetta Verni
- Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
| | - Simona Giunta
- Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
- Rockefeller University, New York, NY, USA
| | - Isabella Saggio
- Department of Biology and Biotechnology, Sapienza University of Rome, Rome, Italy
- CNR Institute of Molecular Biology and Pathology, Italy
- Institute of Structural Biology, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
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