1
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LINC complex regulation of genome organization and function. Curr Opin Genet Dev 2021; 67:130-141. [PMID: 33524904 DOI: 10.1016/j.gde.2020.12.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/25/2020] [Accepted: 12/11/2020] [Indexed: 12/28/2022]
Abstract
The regulation of genomic function is in part mediated through the physical organization and architecture of the nucleus. Disruption to nuclear organization and architecture is increasingly being recognized by its contribution to many diseases. The LINC complexes - protein structures traversing the nuclear envelope, that physically connect the nuclear interior, and hence the genome, to cytoplasmic cytoskeletal networks are an important component in the physical organization of the genome and its function. This connection, potentially allows for the constant detection of environmental mechanical stimuli, resulting in altered regulation of nuclear architecture and genome function, either directly or via the process of mechanotransduction. Here, we review the influences LINC complexes exert on genome functions and their impact on cellular/organismal health.
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2
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Hua R, Wei H, Liu C, Zhang Y, Liu S, Guo Y, Cui Y, Zhang X, Guo X, Li W, Liu M. FBXO47 regulates telomere-inner nuclear envelope integration by stabilizing TRF2 during meiosis. Nucleic Acids Res 2020; 47:11755-11770. [PMID: 31724724 PMCID: PMC7145685 DOI: 10.1093/nar/gkz992] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 10/11/2019] [Accepted: 10/15/2019] [Indexed: 02/06/2023] Open
Abstract
During meiosis, telomere attachment to the inner nuclear envelope is required for proper pairing of homologous chromosomes and recombination. Here, we identified F-box protein 47 (FBXO47) as a regulator of the telomeric shelterin complex that is specifically expressed during meiotic prophase I. Knockout of Fbxo47 in mice leads to infertility in males. We found that the Fbxo47 deficient spermatocytes are unable to form a complete synaptonemal complex. FBXO47 interacts with TRF1/2, and the disruption of Fbxo47 destabilizes TRF2, leading to unstable telomere attachment and slow traversing through the bouquet stage. Our findings uncover a novel mechanism of FBXO47 in telomeric shelterin subunit stabilization during meiosis.
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Affiliation(s)
- Rong Hua
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Huafang Wei
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Chao Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Yue Zhang
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Siyu Liu
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Yueshuai Guo
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Yiqiang Cui
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Xin Zhang
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Xuejiang Guo
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
| | - Wei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Mingxi Liu
- State Key Laboratory of Reproductive Medicine, Center for Global Health, Nanjing Medical University, Nanjing, Jiangsu, 211166, P.R. China
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3
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Koncicka M, Cervenka J, Jahn D, Sucha R, Vodicka P, Gad A, Alsheimer M, Susor A. Expression of lamin C2 in mammalian oocytes. PLoS One 2020; 15:e0229781. [PMID: 32343699 PMCID: PMC7188254 DOI: 10.1371/journal.pone.0229781] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 02/13/2020] [Indexed: 11/23/2022] Open
Abstract
Lamin C2 (LMN C2) is a short product of the lamin a gene. It is a germ cell-specific lamin and has been extensively studied in male germ cells. In this study, we focussed on the expression and localization of LMN C2 in fully-grown germinal vesicle (GV) oocytes. We detected LMN C2 in the fully-grown germinal vesicle oocytes of various mammalian species with confirmation done by immunoblotting the wild type and Lmnc2 gene deleted testes. Expression of LMN C2 tagged with GFP showed localization of LMN C2 to the nuclear membrane of the oocyte. Moreover, the LMN C2 protein notably disappeared after nuclear envelope breakdown (NEBD) and the expression of LMN C2 was significantly reduced in the oocytes from aged females and ceased altogether during meiotic maturation. These results provide new insights regarding LMN C2 expression in the oocytes of various mammalian species.
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Affiliation(s)
- Marketa Koncicka
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
| | - Jakub Cervenka
- Laboratory of Applied Proteome Analyses, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
| | - Daniel Jahn
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Rita Sucha
- Laboratory of Applied Proteome Analyses, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
| | - Petr Vodicka
- Laboratory of Applied Proteome Analyses, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
| | - Ahmed Gad
- Laboratory of Developmental Biology, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
- Department of Animal Production, Faculty of Agriculture, Cairo University, Giza, Egypt
| | - Manfred Alsheimer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Andrej Susor
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Libechov, Czech Republic
- * E-mail:
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4
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Pereira CD, Serrano JB, Martins F, da Cruz E Silva OAB, Rebelo S. Nuclear envelope dynamics during mammalian spermatogenesis: new insights on male fertility. Biol Rev Camb Philos Soc 2019; 94:1195-1219. [PMID: 30701647 DOI: 10.1111/brv.12498] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 01/04/2019] [Accepted: 01/08/2019] [Indexed: 02/06/2023]
Abstract
The production of highly specialized spermatozoa from undifferentiated spermatogonia is a strictly organized and programmed process requiring extensive restructuring of the entire cell. One of the most remarkable cellular transformations accompanying the various phases of spermatogenesis is the profound remodelling of the nuclear architecture, in which the nuclear envelope (NE) seems to be crucially involved. In recent years, several proteins from the distinct layers forming the NE (i.e. the inner and outer nuclear membranes as well as the nuclear lamina) have been associated with meiosis and/or spermiogenesis in different mammalian species. Among these are A- and B-type lamins, Dpy-19-like protein 2 (DPY19L2), lamin B receptor (LBR), lamina-associated polypeptide 1 (LAP1), LAP2/emerin/MAN1 (LEM) domain-containing proteins, spermatogenesis-associated 46 (SPATA46) and diverse elements of the linker of nucleoskeleton and cytoskeleton (LINC) complex, namely Sad-1/UNC-84 homology (SUN) and Klarsicht/ANC-1/Syne-1 homology (KASH) domain-containing proteins. Herein, we summarize the current state of the art on the cellular and subcellular distribution of NE proteins expressed during mammalian spermatogenesis, and discuss the latest research developments regarding their testis-specific functions. This review provides a comprehensive and innovative overview of the NE network as a regulatory platform and as an essential determinant of efficient meiotic chromosome recombination as well as spermiogenesis-associated nuclear remodelling and differentiation in mammalian male germline cells. Thus, this review provides important novel insights on the biological relevance of NE proteins for male fertility.
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Affiliation(s)
- Cátia D Pereira
- Department of Medical Sciences, Neuroscience and Signalling Laboratory, Institute for Biomedicine (iBiMED), University of Aveiro, 3810-193 Aveiro, Portugal
| | - Joana B Serrano
- Department of Medical Sciences, Neuroscience and Signalling Laboratory, Institute for Biomedicine (iBiMED), University of Aveiro, 3810-193 Aveiro, Portugal
| | - Filipa Martins
- Department of Medical Sciences, Neuroscience and Signalling Laboratory, Institute for Biomedicine (iBiMED), University of Aveiro, 3810-193 Aveiro, Portugal
| | - Odete A B da Cruz E Silva
- Department of Medical Sciences, Neuroscience and Signalling Laboratory, Institute for Biomedicine (iBiMED), University of Aveiro, 3810-193 Aveiro, Portugal.,The Discovery CTR, University of Aveiro Campus, 3810-193 Aveiro, Portugal
| | - Sandra Rebelo
- Department of Medical Sciences, Neuroscience and Signalling Laboratory, Institute for Biomedicine (iBiMED), University of Aveiro, 3810-193 Aveiro, Portugal
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5
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Link J, Paouneskou D, Velkova M, Daryabeigi A, Laos T, Labella S, Barroso C, Pacheco Piñol S, Montoya A, Kramer H, Woglar A, Baudrimont A, Markert SM, Stigloher C, Martinez-Perez E, Dammermann A, Alsheimer M, Zetka M, Jantsch V. Transient and Partial Nuclear Lamina Disruption Promotes Chromosome Movement in Early Meiotic Prophase. Dev Cell 2018; 45:212-225.e7. [PMID: 29689196 PMCID: PMC5920155 DOI: 10.1016/j.devcel.2018.03.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 02/13/2018] [Accepted: 03/23/2018] [Indexed: 12/03/2022]
Abstract
Meiotic chromosome movement is important for the pairwise alignment of homologous chromosomes, which is required for correct chromosome segregation. Movement is driven by cytoplasmic forces, transmitted to chromosome ends by nuclear membrane-spanning proteins. In animal cells, lamins form a prominent scaffold at the nuclear periphery, yet the role lamins play in meiotic chromosome movement is unclear. We show that chromosome movement correlates with reduced lamin association with the nuclear rim, which requires lamin phosphorylation at sites analogous to those that open lamina network crosslinks in mitosis. Failure to remodel the lamina results in delayed meiotic entry, altered chromatin organization, unpaired or interlocked chromosomes, and slowed chromosome movement. The remodeling kinases are delivered to lamins via chromosome ends coupled to the nuclear envelope, potentially enabling crosstalk between the lamina and chromosomal events. Thus, opening the lamina network plays a role in modulating contacts between chromosomes and the nuclear periphery during meiosis. Upon meiotic entry, the protein network of the nuclear lamina is opened up/loosened Weakening of lamin crosslinks triggers dramatic chromatin reorganization Failure to remodel lamina crosslinking can lead to aberrant chromosome forms Meiotic phosphorylation of lamin is essential for maintaining chromosome integrity
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Affiliation(s)
- Jana Link
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | - Dimitra Paouneskou
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | - Maria Velkova
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | - Anahita Daryabeigi
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | - Triin Laos
- Department of Microbiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | - Sara Labella
- Department of Biology, McGill University, 1205 Avenue Docteur Penfield, Montreal, QC H2A 1B1, Canada
| | - Consuelo Barroso
- MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Sarai Pacheco Piñol
- MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Alex Montoya
- MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Holger Kramer
- MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Alexander Woglar
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | - Antoine Baudrimont
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | | | - Christian Stigloher
- Imaging Core Facility, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Enrique Martinez-Perez
- MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Alexander Dammermann
- Department of Microbiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria
| | - Manfred Alsheimer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Monique Zetka
- Department of Biology, McGill University, 1205 Avenue Docteur Penfield, Montreal, QC H2A 1B1, Canada
| | - Verena Jantsch
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, 1030 Vienna, Austria.
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Papadopoulos D, Shihan M, Scheiner-Bobis G. Physiological implications of DHEAS-induced non-classical steroid hormone signaling. J Steroid Biochem Mol Biol 2018; 179:73-78. [PMID: 29017935 DOI: 10.1016/j.jsbmb.2017.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 09/28/2017] [Accepted: 10/03/2017] [Indexed: 01/12/2023]
Abstract
In the spermatogenic cell line GC-2, dehydroepiandrosterone sulfate (DHEAS), activates the Src/Ras/c-Raf/Erk1/2/CREB(ATF-1) signaling cascade. Since DHEAS is present in the gonads, and since spermatogenesis and maturation of spermatogonia to haploid spermatozoa requires activation of Erk1/2, the triggering of these signaling events by DHEAS might have physiological relevance. In the Sertoli cell line TM4, DHEAS-induces activation of Erk1/2, CREB, and ATF-1, stimulates expression of claudin-3 and claudin-5 and augments transepithelial resistance, indicating the formation of tight junctions between adjacent Sertoli cells. Thus, by influencing the formation and dynamics of tight junctions at the blood-testis barrier, which protects germ cells from cells of the immune system, DHEAS might play a crucial role in the regulation and maintenance of male fertility. In bEnd.3 brain-derived endothelial cells, DHEAS stimulates the expression of zonula occludens-1 and claudin-3 and promotes tight junction formation between neighboring cells, which at the blood-brain barrier protects the brain from harmful factors and cells. If DHEAS supports the integrity of the blood-brain barrier also in vivo, the current findings might lead to new strategies for the prevention or treatment of neurological disorders associated with barrier defects.
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Affiliation(s)
- Dimitrios Papadopoulos
- Institut für Veterinär-Physiologie und -Biochemie, Fachbereich Veterinärmedizin, Justus-Liebig-Universität Giessen, Germany
| | - Mazen Shihan
- Institut für Veterinär-Physiologie und -Biochemie, Fachbereich Veterinärmedizin, Justus-Liebig-Universität Giessen, Germany
| | - Georgios Scheiner-Bobis
- Institut für Veterinär-Physiologie und -Biochemie, Fachbereich Veterinärmedizin, Justus-Liebig-Universität Giessen, Germany.
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7
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Burke B. LINC complexes as regulators of meiosis. Curr Opin Cell Biol 2018; 52:22-29. [PMID: 29414590 DOI: 10.1016/j.ceb.2018.01.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/11/2018] [Accepted: 01/14/2018] [Indexed: 01/28/2023]
Abstract
Meiosis is a key processes of sexual reproduction in eukaryotes. By combining two cell division cycles with a single round of DNA replication meiosis provides a mechanism to generate haploid gametes. Coincidentally, processes involved in ensuring appropriate segregation of homologous chromosomes also result in genetic recombination and shuffling of genes between each generation. During the first meiotic prophase, rapid telomere-led chromosome movements facilitate alignment and pairing of homologous chromosomes. Forces that produce these movements are generated by the cytoskeleton. Force transmission across the nuclear envelope is dependent upon LINC complexes. These structures consist of SUN and KASH domain proteins that span the two nuclear membranes. Together they represent a pair of links in a molecular chain that couples telomeres to the cytoskeleton. In addition to their force transducing role, LINC complexes also have essential functions ensuring the fidelity of recombination between homologous chromosomes. In this way, LINC complexes are now seen as playing an active and integral role in meiotic progression.
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Affiliation(s)
- Brian Burke
- Institute of Medical Biology, 8A Biomedical Grove, 06-06 Immunos, Singapore 138648, Singapore.
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8
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Abstract
As a compartment border, the nuclear envelope (NE) needs to serve as both a protective membrane shell for the genome and a versatile communication interface between the nucleus and the cytoplasm. Despite its important structural role in sheltering the genome, the NE is a dynamic and highly adaptable boundary that changes composition during differentiation, deforms in response to mechanical challenges, can be repaired upon rupture and even rapidly disassembles and reforms during open mitosis. NE remodelling is fundamentally involved in cell growth, division and differentiation, and if perturbed can lead to devastating diseases such as muscular dystrophies or premature ageing.
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9
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Abstract
The nucleus is separated from the cytosol by the nuclear envelope, which is a double lipid bilayer composed of the outer nuclear membrane and the inner nuclear membrane. The intermediate filament proteins lamin A, lamin B, and lamin C form a network underlying the inner nuclear membrane. This proteinaceous network provides the nucleus with its strength, rigidity, and elasticity. Positioned within the inner nuclear membrane are more than 150 inner nuclear membrane proteins, many of which interact directly with lamins and require lamins for their inner nuclear membrane localization. Inner nuclear membrane proteins and the nuclear lamins define the nuclear lamina. These inner nuclear membrane proteins have tissue-specific expression and diverse functions including regulating cytoskeletal organization, nuclear architecture, cell cycle dynamics, and genomic organization. Loss or mutations in lamins and inner nuclear membrane proteins cause a wide spectrum of diseases. Here, I will review the functions of the well-studied nuclear lamina proteins and the diseases associated with loss or mutations in these proteins. © 2016 American Physiological Society. Compr Physiol 6:1655-1674, 2016.
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Affiliation(s)
- James M. Holaska
- Department of Pharmaceutical Sciences, University of the Sciences, Philadelphia, Pennsylvania, USA
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10
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Upmanyu N, Dietze R, Kirch U, Scheiner-Bobis G. Ouabain interactions with the α4 isoform of the sodium pump trigger non-classical steroid hormone signaling and integrin expression in spermatogenic cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2809-2819. [PMID: 27599714 DOI: 10.1016/j.bbamcr.2016.09.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/22/2016] [Accepted: 09/01/2016] [Indexed: 01/18/2023]
Abstract
In addition to the ubiquitous α1 isoform of the sodium pump, sperm cells also express a male-specific α4 isoform whose function has been associated with sperm motility, fertility, and capacitation. Here we investigate in the murine spermatogenic cell line GC-2 interactions of the α4 isoform with the cardiotonic steroid ouabain in signaling cascades involved in the non-classical action of steroid hormones. Exposure of GC-2 cells to low concentrations of ouabain stimulates the phosphorylation of Erk1/2 and of the transcription factors CREB and ATF-1. As a consequence of this signaling cascade, ouabain stimulates on the mRNA level the expression of integrins αv, β3 and α5, whose expression is also modulated by the cAMP response element. Increased expression of integrins αv and β3 is also seen in cultures of seminiferous tubules exposed to 10nM ouabain. At the protein level we observed a significant stimulation of β3 integrin expression by ouabain. Abrogation of α4 isoform expression by siRNA leads to the complete suppression of all ouabain-induced signaling mentioned above, including its stimulatory effect on the expression of β3 integrin. The results presented here demonstrate for the first time the induction of signaling cascades through the interaction of ouabain with the α4 isoform in a germ-cell derived cell line. The novel finding that these interactions lead to increased expression of integrins in GC-2 cells and the confirmation of these results in the ex vivo experiments indicate that hormone/receptor-like interactions of ouabain with the α4 isoform might be of significance for male physiology.
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Affiliation(s)
- Neha Upmanyu
- Institut für Veterinär-Physiologie und -Biochemie, Fachbereich Veterinärmedizin, Justus-Liebig Universität Giessen, Giessen, Germany
| | - Raimund Dietze
- Institut für Veterinär-Physiologie und -Biochemie, Fachbereich Veterinärmedizin, Justus-Liebig Universität Giessen, Giessen, Germany
| | - Ulrike Kirch
- Institut für Veterinär-Physiologie und -Biochemie, Fachbereich Veterinärmedizin, Justus-Liebig Universität Giessen, Giessen, Germany
| | - Georgios Scheiner-Bobis
- Institut für Veterinär-Physiologie und -Biochemie, Fachbereich Veterinärmedizin, Justus-Liebig Universität Giessen, Giessen, Germany.
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11
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Shibuya H, Hernández-Hernández A, Morimoto A, Negishi L, Höög C, Watanabe Y. MAJIN Links Telomeric DNA to the Nuclear Membrane by Exchanging Telomere Cap. Cell 2015; 163:1252-1266. [PMID: 26548954 DOI: 10.1016/j.cell.2015.10.030] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/16/2015] [Accepted: 09/24/2015] [Indexed: 12/11/2022]
Abstract
In meiosis, telomeres attach to the inner nuclear membrane (INM) and drive the chromosome movement required for homolog pairing and recombination. Here, we address the question of how telomeres are structurally adapted for the meiotic task. We identify a multi-subunit meiotic telomere-complex, TERB1/2-MAJIN, which takes over telomeric DNA from the shelterin complex in mouse germ cells. TERB1/2-MAJIN initially assembles on the INM sequestered by its putative transmembrane subunit MAJIN. In early meiosis, telomere attachment is achieved by the formation of a chimeric complex of TERB1/2-MAJIN and shelterin. The chimeric complex matures during prophase into DNA-bound TERB1/2-MAJIN by releasing shelterin, forming a direct link between telomeric DNA and the INM. These hierarchical processes, termed "telomere cap exchange," are regulated by CDK-dependent phosphorylation and the DNA-binding activity of MAJIN. Further, we uncover a positive feedback between telomere attachment and chromosome movement, revealing a comprehensive regulatory network underlying meiosis-specific telomere function in mammals.
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Affiliation(s)
- Hiroki Shibuya
- Laboratory of Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1Yayoi, Tokyo 113-0032, Japan
| | | | - Akihiro Morimoto
- Laboratory of Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1Yayoi, Tokyo 113-0032, Japan
| | - Lumi Negishi
- Laboratory of Protein Expression and Production, Center for Structural Biology of Challenging Proteins, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Tokyo 113-0032, Japan
| | - Christer Höög
- Department of Cell and Molecular Biology, Karolinska Institute, Stockholm 171 77, Sweden
| | - Yoshinori Watanabe
- Laboratory of Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1Yayoi, Tokyo 113-0032, Japan.
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12
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Peter A, Khandekar S, Deakin JE, Stick R. A peculiar lamin in a peculiar mammal: Expression of lamin LIII in platypus (Ornithorhynchus anatinus). Eur J Cell Biol 2015. [PMID: 26213206 DOI: 10.1016/j.ejcb.2015.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Platypus (Ornithorhynchus anatinus) holds a unique phylogenetic position at the base of the mammalian lineage due to an amalgamation of mammalian and sauropsid-like features. Here we describe the set of four lamin genes for platypus. Lamins are major components of the nuclear lamina, which constitutes a main component of the nucleoskeleton and is involved in a wide range of nuclear functions. Vertebrate evolution was accompanied by an increase in the number of lamin genes from a single gene in their closest relatives, the tunicates and cephalochordates, to four genes in the vertebrate lineage. Of the four genes the LIII gene is characterized by the presence of two alternatively spliced CaaX-encoding exons. In amphibians and fish LIII is the major lamin protein in oocytes and early embryos. The LIII gene is conserved throughout the vertebrate lineage, with the notable exception of marsupials and placental mammals, which have lost the LIII gene. Here we show that platypus has retained an LIII gene, albeit with a significantly altered structure and with a radically different expression pattern. The platypus LIII gene contains only a single CaaX-encoding exon and the head domain together with coil 1a and part of coil1b of the platypus LIII protein is replaced by a novel short non-helical N-terminus. It is expressed exclusively in the testis. These features resemble those of male germ cell-specific lamins in placental mammals, in particular those of lamin C2. Our data suggest (i) that the specific functions of LIII, which it fulfills in all other vertebrates, is no longer required in mammals and (ii) once it had been freed from these functions has undergone structural alterations and has adopted a new functionality in monotremes.
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Affiliation(s)
- Annette Peter
- Department of Cell Biology, FB2, University of Bremen, P.O. Box 33 04 40, 28334 Bremen, Germany
| | - Shaunak Khandekar
- Cellular and Molecular Pharmacology, Louvain Drug Research Institute, Université catholique de Louvain, avenue E. Mounier 73 bte B1.73.05, B-1200 Brussels, Belgium.
| | - Janine E Deakin
- Research School of Biology, ANU College of Medicine, Biology and Environment, Canberra, Australia.
| | - Reimer Stick
- Department of Cell Biology, FB2, University of Bremen, P.O. Box 33 04 40, 28334 Bremen, Germany.
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13
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Chang W, Worman HJ, Gundersen GG. Accessorizing and anchoring the LINC complex for multifunctionality. ACTA ACUST UNITED AC 2015; 208:11-22. [PMID: 25559183 PMCID: PMC4284225 DOI: 10.1083/jcb.201409047] [Citation(s) in RCA: 210] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The linker of nucleoskeleton and cytoskeleton (LINC) complex, composed of outer and inner nuclear membrane Klarsicht, ANC-1, and Syne homology (KASH) and Sad1 and UNC-84 (SUN) proteins, respectively, connects the nucleus to cytoskeletal filaments and performs diverse functions including nuclear positioning, mechanotransduction, and meiotic chromosome movements. Recent studies have shed light on the source of this diversity by identifying factors associated with the complex that endow specific functions as well as those that differentially anchor the complex within the nucleus. Additional diversity may be provided by accessory factors that reorganize the complex into higher-ordered arrays. As core components of the LINC complex are associated with several diseases, understanding the role of accessory and anchoring proteins could provide insights into pathogenic mechanisms.
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Affiliation(s)
- Wakam Chang
- Department of Pathology and Cell Biology and Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032
| | - Howard J Worman
- Department of Pathology and Cell Biology and Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032 Department of Pathology and Cell Biology and Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032
| | - Gregg G Gundersen
- Department of Pathology and Cell Biology and Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032
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14
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Link J, Jahn D, Alsheimer M. Structural and functional adaptations of the mammalian nuclear envelope to meet the meiotic requirements. Nucleus 2015; 6:93-101. [PMID: 25674669 PMCID: PMC4615672 DOI: 10.1080/19491034.2015.1004941] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Numerous studies in the past years provided definite evidence that the nuclear envelope is much more than just a simple barrier. It rather constitutes a multifunctional platform combining structural and dynamic features to fulfill many fundamental functions such as chromatin organization, regulation of transcription, signaling, but also structural duties like maintaining general nuclear architecture and shape. One additional and, without doubt, highly impressive aspect is the recently identified key function of selected nuclear envelope components in driving meiotic chromosome dynamics, which in turn is essential for accurate recombination and segregation of the homologous chromosomes. Here, we summarize the recent work identifying new key players in meiotic telomere attachment and movement and discuss the latest advances in our understanding of the actual function of the meiotic nuclear envelope.
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Affiliation(s)
- Jana Link
- a Department of Cell and Developmental Biology ; Biocenter University Würzburg ; Würzburg , Germany
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15
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Kusch T. Brca2-Pds5 complexes mobilize persistent meiotic recombination sites to the nuclear envelope. J Cell Sci 2015; 128:717-27. [PMID: 25588834 DOI: 10.1242/jcs.159988] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Homologous recombination is required for reciprocal exchange between homologous chromosome arms during meiosis. Only select meiotic recombination events become chromosomal crossovers; the majority of recombination outcomes are noncrossovers. Growing evidence suggests that crossovers are repaired after noncrossovers. Here, I report that persisting recombination sites are mobilized to the nuclear envelope of Drosophila pro-oocytes during mid-pachytene. Their number correlates with the average crossover rate per meiosis. Proteomic and interaction studies reveal that the recombination mediator Brca2 associates with lamin and the cohesion factor Pds5 to secure persistent recombination sites at the nuclear envelope. In Rad51(-/-) females, all persistent DNA breaks are directed to the nuclear envelope. By contrast, a reduction of Pds5 or Brca2 levels abolishes the movement and has a negative impact on crossover rates. The data suggest that persistent meiotic DNA double-strand breaks might correspond to crossovers, which are mobilized to the nuclear envelope for their repair. The identification of Brca2-Pds5 complexes as key mediators of this process provides a first mechanistic explanation for the contribution of lamins and cohesins to meiotic recombination.
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Affiliation(s)
- Thomas Kusch
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854, USA
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16
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Viera A, Alsheimer M, Gómez R, Berenguer I, Ortega S, Symonds CE, Santamaría D, Benavente R, Suja JA. CDK2 regulates nuclear envelope protein dynamics and telomere attachment in mouse meiotic prophase. J Cell Sci 2014; 128:88-99. [PMID: 25380821 DOI: 10.1242/jcs.154922] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In most organisms, telomeres attach to the nuclear envelope at the onset of meiosis to promote the crucial processes of pairing, recombination and synapsis during prophase I. This attachment of meiotic telomeres is mediated by the specific distribution of several nuclear envelope components that interact with the attachment plates of the synaptonemal complex. We have determined by immunofluorescence and electron microscopy that the ablation of the kinase CDK2 alters the nuclear envelope in mouse spermatocytes, and that the proteins SUN1, KASH5 (also known as CCDC155) and lamin C2 show an abnormal cap-like distribution facing the centrosome. Strikingly, some telomeres are not attached to the nuclear envelope but remain at the nuclear interior where they are associated with SUN1 and with nuclear-envelope-detached vesicles. We also demonstrate that mouse testis CDK2 phosphorylates SUN1 in vitro. We propose that during mammalian prophase I the kinase CDK2 is a key factor governing the structure of the nuclear envelope and the telomere-led chromosome movements essential for homolog pairing.
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Affiliation(s)
- Alberto Viera
- Unidad de Biología Celular, Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Manfred Alsheimer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, D-97074 Würzburg, Germany
| | - Rocío Gómez
- Unidad de Biología Celular, Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Inés Berenguer
- Unidad de Biología Celular, Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Sagrario Ortega
- Biotechnology Program, Centro Nacional de Investigaciones Oncológicas, E-28029 Madrid, Spain
| | - Catherine E Symonds
- Molecular Oncology Program, Centro Nacional de Investigaciones Oncológicas, E-28029 Madrid, Spain
| | - David Santamaría
- Molecular Oncology Program, Centro Nacional de Investigaciones Oncológicas, E-28029 Madrid, Spain
| | - Ricardo Benavente
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, D-97074 Würzburg, Germany
| | - José A Suja
- Unidad de Biología Celular, Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
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17
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Cau P, Navarro C, Harhouri K, Roll P, Sigaudy S, Kaspi E, Perrin S, De Sandre-Giovannoli A, Lévy N. Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective. Semin Cell Dev Biol 2014; 29:125-47. [PMID: 24662892 DOI: 10.1016/j.semcdb.2014.03.021] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lamin A-related progeroid syndromes are genetically determined, extremely rare and severe. In the past ten years, our knowledge and perspectives for these diseases has widely progressed, through the progressive dissection of their pathophysiological mechanisms leading to precocious and accelerated aging, from the genes mutations discovery until therapeutic trials in affected children. A-type lamins are major actors in several structural and functional activities at the nuclear periphery, as they are major components of the nuclear lamina. However, while this is usually poorly considered, they also play a key role within the rest of the nucleoplasm, whose defects are related to cell senescence. Although nuclear shape and nuclear envelope deformities are obvious and visible events, nuclear matrix disorganization and abnormal composition certainly represent the most important causes of cell defects with dramatic pathological consequences. Therefore, lamin-associated diseases should be better referred as laminopathies instead of envelopathies, this later being too restrictive, considering neither the key structural and functional roles of soluble lamins in the entire nucleoplasm, nor the nuclear matrix contribution to the pathophysiology of lamin-associated disorders and in particular in defective lamin A processing-associated aging diseases. Based on both our understanding of pathophysiological mechanisms and the biological and clinical consequences of progeria and related diseases, therapeutic trials have been conducted in patients and were terminated less than 10 years after the gene discovery, a quite fast issue for a genetic disease. Pharmacological drugs have been repurposed and used to decrease the toxicity of the accumulated, unprocessed and truncated prelaminA in progeria. To date, none of them may be considered as a cure for progeria and these clinical strategies were essentially designed toward reducing a subset of the most dramatic and morbid features associated to progeria. New therapeutic strategies under study, in particular targeting the protein expression pathway at the mRNA level, have shown a remarkable efficacy both in vitro in cells and in vivo in mice models. Strategies intending to clear the toxic accumulated proteins from the nucleus are also under evaluation. However, although exceedingly rare, improving our knowledge of genetic progeroid syndromes and searching for innovative and efficient therapies in these syndromes is of paramount importance as, even before they can be used to save lives, they may significantly (i) expand the affected childrens' lifespan and preserve their quality of life; (ii) improve our understanding of aging-related disorders and other more common diseases; and (iii) expand our fundamental knowledge of physiological aging and its links with major physiological processes such as those involved in oncogenesis.
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Affiliation(s)
- Pierre Cau
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France.
| | - Claire Navarro
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Karim Harhouri
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Patrice Roll
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Sabine Sigaudy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Elise Kaspi
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Sophie Perrin
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Annachiara De Sandre-Giovannoli
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Nicolas Lévy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France.
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18
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Link J, Jahn D, Schmitt J, Göb E, Baar J, Ortega S, Benavente R, Alsheimer M. The meiotic nuclear lamina regulates chromosome dynamics and promotes efficient homologous recombination in the mouse. PLoS Genet 2013; 9:e1003261. [PMID: 23382700 PMCID: PMC3561109 DOI: 10.1371/journal.pgen.1003261] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 12/02/2012] [Indexed: 12/22/2022] Open
Abstract
The nuclear lamina is the structural scaffold of the nuclear envelope and is well known for its central role in nuclear organization and maintaining nuclear stability and shape. In the past, a number of severe human disorders have been identified to be associated with mutations in lamins. Extensive research on this topic has provided novel important clues about nuclear lamina function. These studies have contributed to the knowledge that the lamina constitutes a complex multifunctional platform combining both structural and regulatory functions. Here, we report that, in addition to the previously demonstrated significance for somatic cell differentiation and maintenance, the nuclear lamina is also an essential determinant for germ cell development. Both male and female mice lacking the short meiosis-specific A-type lamin C2 have a severely defective meiosis, which at least in the male results in infertility. Detailed analysis revealed that lamin C2 is required for telomere-driven dynamic repositioning of meiotic chromosomes. Loss of lamin C2 affects precise synapsis of the homologs and interferes with meiotic double-strand break repair. Taken together, our data explain how the nuclear lamina contributes to meiotic chromosome behaviour and accurate genome haploidization on a mechanistic level.
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Affiliation(s)
- Jana Link
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Daniel Jahn
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Johannes Schmitt
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Eva Göb
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Johannes Baar
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | | | - Ricardo Benavente
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Manfred Alsheimer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
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19
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Fritsche M, Reinholdt LG, Lessard M, Handel MA, Bewersdorf J, Heermann DW. The impact of entropy on the spatial organization of synaptonemal complexes within the cell nucleus. PLoS One 2012; 7:e36282. [PMID: 22574147 PMCID: PMC3344857 DOI: 10.1371/journal.pone.0036282] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 04/03/2012] [Indexed: 01/08/2023] Open
Abstract
We employ 4Pi-microscopy to study SC organization in mouse spermatocyte nuclei allowing for the three-dimensional reconstruction of the SC's backbone arrangement. Additionally, we model the SCs in the cell nucleus by confined, self-avoiding polymers, whose chain ends are attached to the envelope of the confining cavity and diffuse along it. This work helps to elucidate the role of entropy in shaping pachytene SC organization. The framework provided by the complex interplay between SC polymer rigidity, tethering and confinement is able to qualitatively explain features of SC organization, such as mean squared end-to-end distances, mean squared center-of-mass distances, or SC density distributions. However, it fails in correctly assessing SC entanglement within the nucleus. In fact, our analysis of the 4Pi-microscopy images reveals a higher ordering of SCs within the nuclear volume than what is expected by our numerical model. This suggests that while effects of entropy impact SC organization, the dedicated action of proteins or actin cables is required to fine-tune the spatial ordering of SCs within the cell nucleus.
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Affiliation(s)
- Miriam Fritsche
- Institute for Theoretical Physics, University of Heidelberg, Heidelberg, Germany.
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