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Lezcano ÓM, Sánchez-Polo M, Ruiz JL, Gómez-Díaz E. Chromatin Structure and Function in Mosquitoes. Front Genet 2020; 11:602949. [PMID: 33365050 PMCID: PMC7750206 DOI: 10.3389/fgene.2020.602949] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/29/2020] [Indexed: 12/27/2022] Open
Abstract
The principles and function of chromatin and nuclear architecture have been extensively studied in model organisms, such as Drosophila melanogaster. However, little is known about the role of these epigenetic processes in transcriptional regulation in other insects including mosquitoes, which are major disease vectors and a worldwide threat for human health. Some of these life-threatening diseases are malaria, which is caused by protozoan parasites of the genus Plasmodium and transmitted by Anopheles mosquitoes; dengue fever, which is caused by an arbovirus mainly transmitted by Aedes aegypti; and West Nile fever, which is caused by an arbovirus transmitted by Culex spp. In this contribution, we review what is known about chromatin-associated mechanisms and the 3D genome structure in various mosquito vectors, including Anopheles, Aedes, and Culex spp. We also discuss the similarities between epigenetic mechanisms in mosquitoes and the model organism Drosophila melanogaster, and advocate that the field could benefit from the cross-application of state-of-the-art functional genomic technologies that are well-developed in the fruit fly. Uncovering the mosquito regulatory genome can lead to the discovery of unique regulatory networks associated with the parasitic life-style of these insects. It is also critical to understand the molecular interactions between the vectors and the pathogens that they transmit, which could hold the key to major breakthroughs on the fight against mosquito-borne diseases. Finally, it is clear that epigenetic mechanisms controlling mosquito environmental plasticity and evolvability are also of utmost importance, particularly in the current context of globalization and climate change.
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Affiliation(s)
| | | | - José L. Ruiz
- Instituto de Parasitología y Biomedicina López-Neyra (IPBLN), Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Elena Gómez-Díaz
- Instituto de Parasitología y Biomedicina López-Neyra (IPBLN), Consejo Superior de Investigaciones Científicas, Granada, Spain
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2
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Cremer T, Cremer M, Hübner B, Silahtaroglu A, Hendzel M, Lanctôt C, Strickfaden H, Cremer C. The Interchromatin Compartment Participates in the Structural and Functional Organization of the Cell Nucleus. Bioessays 2020; 42:e1900132. [PMID: 31994771 DOI: 10.1002/bies.201900132] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/24/2019] [Indexed: 12/11/2022]
Abstract
This article focuses on the role of the interchromatin compartment (IC) in shaping nuclear landscapes. The IC is connected with nuclear pore complexes (NPCs) and harbors splicing speckles and nuclear bodies. It is postulated that the IC provides routes for imported transcription factors to target sites, for export routes of mRNA as ribonucleoproteins toward NPCs, as well as for the intranuclear passage of regulatory RNAs from sites of transcription to remote functional sites (IC hypothesis). IC channels are lined by less-compacted euchromatin, called the perichromatin region (PR). The PR and IC together form the active nuclear compartment (ANC). The ANC is co-aligned with the inactive nuclear compartment (INC), comprising more compacted heterochromatin. It is postulated that the INC is accessible for individual transcription factors, but inaccessible for larger macromolecular aggregates (limited accessibility hypothesis). This functional nuclear organization depends on still unexplored movements of genes and regulatory sequences between the two compartments.
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Affiliation(s)
- Thomas Cremer
- Anthropology and Human Genomics, Department of Biology II, Ludwig-Maximilians University (LMU), Biocenter, Grosshadernerstr. 2, 82152, Martinsried, Germany
| | - Marion Cremer
- Anthropology and Human Genomics, Department of Biology II, Ludwig-Maximilians University (LMU), Biocenter, Grosshadernerstr. 2, 82152, Martinsried, Germany
| | - Barbara Hübner
- Anthropology and Human Genomics, Department of Biology II, Ludwig-Maximilians University (LMU), Biocenter, Grosshadernerstr. 2, 82152, Martinsried, Germany
| | - Asli Silahtaroglu
- Department of Cellular and Molecular Medicine Faculty of Health and Medical Sciences, University of Copenhagen, Nørre Alle 14, Byg.18.03, 2200, Copenhagen N, Denmark
| | - Michael Hendzel
- Department of Oncology, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta, T6G 1Z2, Canada
| | - Christian Lanctôt
- Integration Santé, 1250 Avenue de la Station local 2-304, Shawinigan, Québec, G9N 8K9, Canada
| | - Hilmar Strickfaden
- Department of Oncology, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta, T6G 1Z2, Canada
| | - Christoph Cremer
- Institute of Molecular Biology (IMB) Ackermannweg 4, 55128 Mainz, Germany, and Institute of Pharmacy & Molecular Biotechnology (IPMB), University Heidelberg, Im Neuenheimer Feld 364, 69120, Heidelberg, Germany
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3
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Compton A, Sharakhov IV, Tu Z. Recent advances and future perspectives in vector-omics. CURRENT OPINION IN INSECT SCIENCE 2020; 40:94-103. [PMID: 32650287 PMCID: PMC8041138 DOI: 10.1016/j.cois.2020.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 05/07/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
We have reviewed recent progress and the remaining challenges in vector-omics. We have highlighted several technologies and applications that facilitate novel biological insights beyond achieving a reference-quality genome assembly. Among other topics, we have discussed the applications of chromatin conformation capture, chromatin accessibility assays, optical mapping, full-length RNA sequencing, single cell RNA analysis, proteomics, and population genomics. We anticipate that we will witness a great expansion in vector-omics research not only in its application in a broad range of species, but also its ability to uncover novel genetic elements and tackle previously inaccessible regions of the genome. It is our hope that the continued innovation in device portability, cost reduction, and informatics support will in the foreseeable future bring vector-omics to every vector laboratory and field station in the world, which will have an unparalleled impact on basic research and the control of vector-borne infectious diseases.
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Affiliation(s)
- Austin Compton
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, United States; Fralin Life Science Institute, Virginia Tech, Blacksburg, VA 24061, United States
| | - Igor V Sharakhov
- Fralin Life Science Institute, Virginia Tech, Blacksburg, VA 24061, United States; Department of Entomology, Virginia Tech, Blacksburg, VA 24061, United States; The Interdisciplinary PhD Program in Genetics, Bioinformatics, and Computational Biology, Virginia Tech, Blacksburg, VA 24061, United States; Department of Genetics and Cell Biology, Tomsk State University, Tomsk 634050, Russia
| | - Zhijian Tu
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, United States; Department of Entomology, Virginia Tech, Blacksburg, VA 24061, United States; The Interdisciplinary PhD Program in Genetics, Bioinformatics, and Computational Biology, Virginia Tech, Blacksburg, VA 24061, United States.
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4
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Locatelli M, Vidi PA. Special issue: Nuclear architecture and chromatin motions in the DNA damage response. Mutat Res 2020; 821:111721. [PMID: 32846362 PMCID: PMC9581968 DOI: 10.1016/j.mrfmmm.2020.111721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Affiliation(s)
- Maëlle Locatelli
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Pierre-Alexandre Vidi
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
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5
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Mir M, Bickmore W, Furlong EEM, Narlikar G. Chromatin topology, condensates and gene regulation: shifting paradigms or just a phase? Development 2019; 146:dev182766. [PMID: 31554625 PMCID: PMC6803379 DOI: 10.1242/dev.182766] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In the past decade, two major advances in our understanding of nuclear organization have taken the field of gene regulation by storm. First, technologies that can analyze the three-dimensional conformation of chromatin have revealed how the genome is organized and have provided novel insights into how regulatory regions in the genome interact. Second, the recognition that many proteins can form membraneless compartments through liquid-liquid phase separation (LLPS) has challenged long-standing notions of how proteins within the nucleus are organized and has offered a tantalizing general mechanism by which many aspects of nuclear function may be regulated. However, the functional roles of chromatin topology and LLPS in regulating gene expression remain poorly understood. These topics were discussed with great fervor during an open discussion held at a recent workshop titled 'Chromatin-based regulation of development' organized by The Company of Biologists. Here, we summarize the major points covered during this debate and discuss how they tie into current thinking in the field of gene regulation.
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Affiliation(s)
- Mustafa Mir
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Wendy Bickmore
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Eileen E M Furlong
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Geeta Narlikar
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
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6
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Fowler KE, Mandawala AA, Griffin DK. The role of chromosome segregation and nuclear organisation in human subfertility. Biochem Soc Trans 2019; 47:425-432. [DOI: 10.1042/bst20180231] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Abstract
Spermatogenesis is central to successful sexual reproduction, producing large numbers of haploid motile male gametes. Throughout this process, a series of equational and reductional chromosome segregation precedes radical repackaging of the haploid genome. Faithful chromosome segregation is thus crucial, as is an ordered spatio-temporal ‘dance’ of packing a large amount of chromatin into a very small space. Ergo, when the process goes wrong, this is associated with an improper chromosome number, nuclear position and/or chromatin damage in the sperm head. Generally, screening for overall DNA damage is relatively commonplace in clinics, but aneuploidy assessment is less so and nuclear organisation studies form the basis of academic research. Several studies have focussed on the role of chromosome segregation, nuclear organisation and analysis of sperm morphometry in human subfertility observing significant alterations in some cases, especially of the sex chromosomes. Importantly, sperm DNA damage has been associated with infertility and both extrinsic (e.g. lifestyle) and intrinsic (e.g. reactive oxygen species levels) factors, and while some DNA-strand breaks are repaired, unexpected breaks can cause differential chromatin packaging and further breakage. A ‘healthy’ sperm nucleus (with the right number of chromosomes, nuclear organisation and minimal DNA damage) is thus an essential part of reproduction. The purpose of this review is to summarise state of the art in the fields of sperm aneuploidy assessment, nuclear organisation and DNA damage studies.
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Affiliation(s)
- Katie E. Fowler
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, U.K
| | - Anjali A. Mandawala
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, U.K
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7
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Dillinger S, Straub T, Németh A. Nucleolus association of chromosomal domains is largely maintained in cellular senescence despite massive nuclear reorganisation. PLoS One 2017; 12:e0178821. [PMID: 28575119 PMCID: PMC5456395 DOI: 10.1371/journal.pone.0178821] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 05/21/2017] [Indexed: 01/10/2023] Open
Abstract
Mammalian chromosomes are organized in structural and functional domains of 0.1–10 Mb, which are characterized by high self-association frequencies in the nuclear space and different contact probabilities with nuclear sub-compartments. They exhibit distinct chromatin modification patterns, gene expression levels and replication timing. Recently, nucleolus-associated chromosomal domains (NADs) have been discovered, yet their precise genomic organization and dynamics are still largely unknown. Here, we use nucleolus genomics and single-cell experiments to address these questions in human embryonic fibroblasts during replicative senescence. Genome-wide mapping reveals 1,646 NADs in proliferating cells, which cover about 38% of the annotated human genome. They are mainly heterochromatic and correlate with late replicating loci. Using Hi-C data analysis, we show that interactions of NADs dominate interphase chromosome contacts in the 10–50 Mb distance range. Interestingly, only minute changes in nucleolar association are observed upon senescence. These spatial rearrangements in subdomains smaller than 100 kb are accompanied with local transcriptional changes. In contrast, large centromeric and pericentromeric satellite repeat clusters extensively dissociate from nucleoli in senescent cells. Accordingly, H3K9me3-marked heterochromatin gets remodelled at the perinucleolar space as revealed by immunofluorescence analyses. Collectively, this study identifies connections between the nucleolus, 3D genome structure, and cellular aging at the level of interphase chromosome organization.
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Affiliation(s)
- Stefan Dillinger
- Biochemistry Center Regensburg, University of Regensburg, Regensburg, Germany
| | - Tobias Straub
- Biomedical Center, Bioinformatics, Ludwig-Maximilians-University, Munich, Germany
| | - Attila Németh
- Biochemistry Center Regensburg, University of Regensburg, Regensburg, Germany
- * E-mail: ,
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8
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van de Werken HJG, Haan JC, Feodorova Y, Bijos D, Weuts A, Theunis K, Holwerda SJB, Meuleman W, Pagie L, Thanisch K, Kumar P, Leonhardt H, Marynen P, van Steensel B, Voet T, de Laat W, Solovei I, Joffe B. Small chromosomal regions position themselves autonomously according to their chromatin class. Genome Res 2017; 27:922-933. [PMID: 28341771 PMCID: PMC5453326 DOI: 10.1101/gr.213751.116] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 03/22/2017] [Indexed: 11/24/2022]
Abstract
The spatial arrangement of chromatin is linked to the regulation of nuclear processes. One striking aspect of nuclear organization is the spatial segregation of heterochromatic and euchromatic domains. The mechanisms of this chromatin segregation are still poorly understood. In this work, we investigated the link between the primary genomic sequence and chromatin domains. We analyzed the spatial intranuclear arrangement of a human artificial chromosome (HAC) in a xenospecific mouse background in comparison to an orthologous region of native mouse chromosome. The two orthologous regions include segments that can be assigned to three major chromatin classes according to their gene abundance and repeat repertoire: (1) gene-rich and SINE-rich euchromatin; (2) gene-poor and LINE/LTR-rich heterochromatin; and (3) gene-depleted and satellite DNA-containing constitutive heterochromatin. We show, using fluorescence in situ hybridization (FISH) and 4C-seq technologies, that chromatin segments ranging from 0.6 to 3 Mb cluster with segments of the same chromatin class. As a consequence, the chromatin segments acquire corresponding positions in the nucleus irrespective of their chromosomal context, thereby strongly suggesting that this is their autonomous property. Interactions with the nuclear lamina, although largely retained in the HAC, reveal less autonomy. Taken together, our results suggest that building of a functional nucleus is largely a self-organizing process based on mutual recognition of chromosome segments belonging to the major chromatin classes.
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Affiliation(s)
- Harmen J G van de Werken
- Cancer Computational Biology Center, Erasmus MC Cancer Institute & Department of Urology, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 CN, Rotterdam, The Netherlands.,Hubrecht Institute-KNAW & University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Josien C Haan
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Yana Feodorova
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Dominika Bijos
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - An Weuts
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Koen Theunis
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Sjoerd J B Holwerda
- Hubrecht Institute-KNAW & University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Wouter Meuleman
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Ludo Pagie
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Katharina Thanisch
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Parveen Kumar
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Heinrich Leonhardt
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Peter Marynen
- Human Genome Laboratory, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Bas van Steensel
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Thierry Voet
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Wouter de Laat
- Hubrecht Institute-KNAW & University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Irina Solovei
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Boris Joffe
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
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9
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Solovei I, Thanisch K, Feodorova Y. How to rule the nucleus: divide et impera. Curr Opin Cell Biol 2016; 40:47-59. [PMID: 26938331 DOI: 10.1016/j.ceb.2016.02.014] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 02/04/2016] [Accepted: 02/14/2016] [Indexed: 01/14/2023]
Abstract
Genome-wide molecular studies have provided new insights into the organization of nuclear chromatin by revealing the presence of chromatin domains of differing transcriptional activity, frequency of cis-interactions, proximity to scaffolding structures and replication timing. These studies have not only brought our understanding of genome function to a new level, but also offered functional insight for many phenomena observed in microscopic studies. In this review, we discuss the major principles of nuclear organization based on the spatial segregation of euchromatin and heterochromatin, as well as the dynamic genome rearrangements occurring during cell differentiation and development. We hope to unite the existing molecular and microscopic data on genome organization to get a holistic view of the nucleus, and propose a model, in which repeat repertoire together with scaffolding structures blueprint the functional nuclear architecture.
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Affiliation(s)
- Irina Solovei
- Department of Biology II, Ludwig Maximilians University Munich, Grosshadernerstrasse 2, Planegg-Martinsried 82152, Germany.
| | - Katharina Thanisch
- Department of Biology II, Ludwig Maximilians University Munich, Grosshadernerstrasse 2, Planegg-Martinsried 82152, Germany
| | - Yana Feodorova
- Department of Biology II, Ludwig Maximilians University Munich, Grosshadernerstrasse 2, Planegg-Martinsried 82152, Germany; Department of Medical Biology, Medical University-Plovdiv, Boulevard Vasil Aprilov 15A, Plovdiv 4000, Bulgaria
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10
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Venkatesan S, Natarajan AT, Hande MP. Chromosomal instability--mechanisms and consequences. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2015; 793:176-84. [PMID: 26520388 DOI: 10.1016/j.mrgentox.2015.08.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 08/21/2015] [Indexed: 01/08/2023]
Abstract
Chromosomal instability is defined as a state of numerical and/or structural chromosomal anomalies in cells. Numerous studies have documented the incidence of chromosomal instability, which acutely or chronically may lead to accelerated ageing (tissue-wide or even organismal), cancer or other genetic disorders. Potential mechanisms leading to the generation of chromosome-genome instability include erroneous/inefficient DNA repair, chromosome segregation defects, spindle assembly defects, DNA replication stress, telomere shortening/dysfunction - to name a few. Understanding the cellular and molecular mechanisms for chromosomal instability in various human cells and tissues will be useful in elucidating the cause for many age associated diseases including cancer. This approach holds a great promise for the cytogenetic assays not only for prognosis but also for diagnostic purposes in clinical settings. In this review, a multi-dimensional approach has been attempted to portray the complexity behind the incidence of chromosome-genome instability including evolutionary implications at the species level for some of the mechanisms of chromosomal instability.
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Affiliation(s)
- Shriram Venkatesan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597
| | - Adayapalam T Natarajan
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo 01100, Italy
| | - M Prakash Hande
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597; Tembusu College, National University of Singapore, Singapore, 138597.
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11
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Arsuaga J, Jayasinghe RG, Scharein RG, Segal MR, Stolz RH, Vazquez M. Current theoretical models fail to predict the topological complexity of the human genome. Front Mol Biosci 2015; 2:48. [PMID: 26347874 PMCID: PMC4543886 DOI: 10.3389/fmolb.2015.00048] [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] [Received: 03/30/2015] [Accepted: 08/06/2015] [Indexed: 11/13/2022] Open
Abstract
Understanding the folding of the human genome is a key challenge of modern structural biology. The emergence of chromatin conformation capture assays (e.g., Hi-C) has revolutionized chromosome biology and provided new insights into the three dimensional structure of the genome. The experimental data are highly complex and need to be analyzed with quantitative tools. It has been argued that the data obtained from Hi-C assays are consistent with a fractal organization of the genome. A key characteristic of the fractal globule is the lack of topological complexity (knotting or inter-linking). However, the absence of topological complexity contradicts results from polymer physics showing that the entanglement of long linear polymers in a confined volume increases rapidly with the length and with decreasing volume. In vivo and in vitro assays support this claim in some biological systems. We simulate knotted lattice polygons confined inside a sphere and demonstrate that their contact frequencies agree with the human Hi-C data. We conclude that the topological complexity of the human genome cannot be inferred from current Hi-C data.
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Affiliation(s)
- Javier Arsuaga
- Department of Mathematics, University of California, Davis Davis, CA, USA ; Department of Molecular and Cellular Biology, University of California, Davis Davis, CA, USA
| | - Reyka G Jayasinghe
- Division of Biology and Biomedical Sciences, Department of Medicine, Department of Genetics, The Genome Institute at Washington University in St. Louis St. Louis, MO, USA
| | | | - Mark R Segal
- Department of Epidemiology and Biostatistics, University of California, San Francisco San Francisco, CA, USA
| | - Robert H Stolz
- Department of Microbiology and Molecular Genetics, University of California, Davis Davis, CA, USA
| | - Mariel Vazquez
- Department of Mathematics, University of California, Davis Davis, CA, USA ; Department of Microbiology and Molecular Genetics, University of California, Davis Davis, CA, USA
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12
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Sharakhov IV, Sharakhova MV. Heterochromatin, histone modifications, and nuclear architecture in disease vectors. CURRENT OPINION IN INSECT SCIENCE 2015; 10:110-117. [PMID: 26097808 PMCID: PMC4470418 DOI: 10.1016/j.cois.2015.05.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Interactions between a pathogen and a vector are plastic and dynamic. Such interactions can be more rapidly accommodated by epigenetic changes than by genetic mutations. Gene expression can be affected by the proximity to the heterochromatin, by local histone modifications, and by the three-dimensional position within the nucleus. Recent studies of disease vectors indicate that gene regulation by these factors can be important for susceptibility to pathogens, reproduction, immunity, development, and longevity. Knowledge about heterochromatin, histone modifications, and nuclear architecture will help our understanding of epigenetic mechanisms that control gene function at traits related to vectorial capacity.
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Affiliation(s)
- Igor V Sharakhov
- Department of Entomology, Virginia Tech, Blacksburg, Virginia, USA
| | - Maria V Sharakhova
- Department of Entomology, Virginia Tech, Blacksburg, Virginia, USA ; Research Institute of Biology and Biophysics, Tomsk State University, Tomsk, Russia
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13
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Cremer T, Cremer M, Hübner B, Strickfaden H, Smeets D, Popken J, Sterr M, Markaki Y, Rippe K, Cremer C. The 4D nucleome: Evidence for a dynamic nuclear landscape based on co-aligned active and inactive nuclear compartments. FEBS Lett 2015; 589:2931-43. [PMID: 26028501 DOI: 10.1016/j.febslet.2015.05.037] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 05/19/2015] [Accepted: 05/20/2015] [Indexed: 02/04/2023]
Abstract
Recent methodological advancements in microscopy and DNA sequencing-based methods provide unprecedented new insights into the spatio-temporal relationships between chromatin and nuclear machineries. We discuss a model of the underlying functional nuclear organization derived mostly from electron and super-resolved fluorescence microscopy studies. It is based on two spatially co-aligned, active and inactive nuclear compartments (ANC and INC). The INC comprises the compact, transcriptionally inactive core of chromatin domain clusters (CDCs). The ANC is formed by the transcriptionally active periphery of CDCs, called the perichromatin region (PR), and the interchromatin compartment (IC). The IC is connected to nuclear pores and serves nuclear import and export functions. The ANC is the major site of RNA synthesis. It is highly enriched in epigenetic marks for transcriptionally competent chromatin and RNA Polymerase II. Marks for silent chromatin are enriched in the INC. Multi-scale cross-correlation spectroscopy suggests that nuclear architecture resembles a random obstacle network for diffusing proteins. An increased dwell time of proteins and protein complexes within the ANC may help to limit genome scanning by factors or factor complexes to DNA exposed within the ANC.
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Affiliation(s)
- Thomas Cremer
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany.
| | - Marion Cremer
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Barbara Hübner
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Hilmar Strickfaden
- University of Alberta, Cross Cancer Institute Dept. of Oncology, Edmonton, AB, Canada
| | - Daniel Smeets
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Jens Popken
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Michael Sterr
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Yolanda Markaki
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Karsten Rippe
- German Cancer Research Center (DKFZ) & BioQuant Center, Research Group Genome Organization & Function, Heidelberg, Germany.
| | - Christoph Cremer
- Institute of Molecular Biology (IMB), Mainz and Institute of Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, Germany.
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14
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Wang R, Mozziconacci J, Bancaud A, Gadal O. Principles of chromatin organization in yeast: relevance of polymer models to describe nuclear organization and dynamics. Curr Opin Cell Biol 2015; 34:54-60. [PMID: 25956973 DOI: 10.1016/j.ceb.2015.04.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 03/17/2015] [Accepted: 04/15/2015] [Indexed: 11/29/2022]
Abstract
Nuclear organization can impact on all aspects of the genome life cycle. This organization is thoroughly investigated by advanced imaging and chromosome conformation capture techniques, providing considerable amount of datasets describing the spatial organization of chromosomes. In this review, we will focus on polymer models to describe chromosome statics and dynamics in the yeast Saccharomyces cerevisiae. We suggest that the equilibrium configuration of a polymer chain tethered at both ends and placed in a confined volume is consistent with the current literature, implying that local chromatin interactions play a secondary role in yeast nuclear organization. Future challenges are to reach an integrated multi-scale description of yeast chromosome organization, which is crucially needed to improve our understanding of the regulation of genomic transaction.
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Affiliation(s)
- Renjie Wang
- LBME du CNRS, France; Laboratoire de Biologie Moleculaire Eucaryote, Université de Toulouse, 118 route de Narbonne, F-31000 Toulouse, France
| | - Julien Mozziconacci
- Laboratory for Theoretical Physics of Condensed Matter UMR7600, Sorbonne University, UPMC, 75005 Paris, France; Groupement de recherche Architecture et Dynamique Nucléaire (GDR ADN), France
| | - Aurélien Bancaud
- Groupement de recherche Architecture et Dynamique Nucléaire (GDR ADN), France; CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France; Univ de Toulouse, LAAS, F-31400 Toulouse, France
| | - Olivier Gadal
- LBME du CNRS, France; Laboratoire de Biologie Moleculaire Eucaryote, Université de Toulouse, 118 route de Narbonne, F-31000 Toulouse, France; Groupement de recherche Architecture et Dynamique Nucléaire (GDR ADN), France.
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