1
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Iida S, Ide S, Tamura S, Sasai M, Tani T, Goto T, Shribak M, Maeshima K. Orientation-independent-DIC imaging reveals that a transient rise in depletion attraction contributes to mitotic chromosome condensation. Proc Natl Acad Sci U S A 2024; 121:e2403153121. [PMID: 39190347 DOI: 10.1073/pnas.2403153121] [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: 02/14/2024] [Accepted: 07/19/2024] [Indexed: 08/28/2024] Open
Abstract
Genomic information must be faithfully transmitted into two daughter cells during mitosis. To ensure the transmission process, interphase chromatin is further condensed into mitotic chromosomes. Although protein factors like condensins and topoisomerase IIα are involved in the assembly of mitotic chromosomes, the physical bases of the condensation process remain unclear. Depletion attraction/macromolecular crowding, an effective attractive force that arises between large structures in crowded environments around chromosomes, may contribute to the condensation process. To approach this issue, we investigated the "chromosome milieu" during mitosis of living human cells using an orientation-independent-differential interference contrast module combined with a confocal laser scanning microscope, which is capable of precisely mapping optical path differences and estimating molecular densities. We found that the molecular density surrounding chromosomes increased with the progression from prophase to anaphase, concurring with chromosome condensation. However, the molecular density went down in telophase, when chromosome decondensation began. Changes in the molecular density around chromosomes by hypotonic or hypertonic treatment consistently altered the condensation levels of chromosomes. In vitro, native chromatin was converted into liquid droplets of chromatin in the presence of cations and a macromolecular crowder. Additional crowder made the chromatin droplets stiffer and more solid-like. These results suggest that a transient rise in depletion attraction, likely triggered by the relocation of macromolecules (proteins, RNAs, and others) via nuclear envelope breakdown and by a subsequent decrease in cell volumes, contributes to mitotic chromosome condensation, shedding light on a different aspect of the condensation mechanism in living human cells.
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Affiliation(s)
- Shiori Iida
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Graduate Institute for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan
| | - Satoru Ide
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Graduate Institute for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan
| | - Sachiko Tamura
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Masaki Sasai
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan
- Department of Complex Systems Science, Nagoya University, Nagoya 464-8603, Japan
| | - Tomomi Tani
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Ikeda, Osaka 563-8577, Japan
| | - Tatsuhiko Goto
- Research Center for Global Agromedicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
- Department of Life and Food Sciences, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
| | | | - Kazuhiro Maeshima
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Graduate Institute for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan
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2
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Ros-Pardo D, Gómez-Puertas P, Marcos-Alcalde Í. STAG2-RAD21 complex: A unidirectional DNA ratchet mechanism in loop extrusion. Int J Biol Macromol 2024; 276:133822. [PMID: 39002918 DOI: 10.1016/j.ijbiomac.2024.133822] [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: 02/05/2024] [Revised: 07/08/2024] [Accepted: 07/09/2024] [Indexed: 07/15/2024]
Abstract
DNA loop extrusion plays a key role in the regulation of gene expression and the structural arrangement of chromatin. Most existing mechanistic models of loop extrusion depend on some type of ratchet mechanism, which should permit the elongation of loops while preventing their collapse, by enabling DNA to move in only one direction. STAG2 is already known to exert a role as DNA anchor, but the available structural data suggest a possible role in unidirectional DNA motion. In this work, a computational simulation framework was constructed to evaluate whether STAG2 could enforce such unidirectional displacement of a DNA double helix. The results reveal that STAG2 V-shape allows DNA sliding in one direction, but blocks opposite DNA movement via a linear ratchet mechanism. Furthermore, these results suggest that RAD21 binding to STAG2 controls its flexibility by narrowing the opening of its V-shape, which otherwise remains widely open in absence of RAD21. Therefore, in the proposed model, in addition to its already described role as a DNA anchor, the STAG2-RAD21 complex would be part of a ratchet mechanism capable of exerting directional selectivity on DNA sliding during loop extrusion. The identification of the molecular basis of the ratchet mechanism of loop extrusion is a critical step in unraveling new insights into a broad spectrum of chromatin activities and their implications for the mechanisms of chromatin-related diseases.
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Affiliation(s)
- David Ros-Pardo
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, CL Nicolás Cabrera, 1, 28049 Madrid, Spain
| | - Paulino Gómez-Puertas
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, CL Nicolás Cabrera, 1, 28049 Madrid, Spain.
| | - Íñigo Marcos-Alcalde
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, CL Nicolás Cabrera, 1, 28049 Madrid, Spain
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3
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Malumbres M, Villarroya-Beltri C. Mosaic variegated aneuploidy in development, ageing and cancer. Nat Rev Genet 2024:10.1038/s41576-024-00762-6. [PMID: 39169218 DOI: 10.1038/s41576-024-00762-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/27/2024] [Indexed: 08/23/2024]
Abstract
Mosaic variegated aneuploidy (MVA) is a rare condition in which abnormal chromosome counts (that is, aneuploidies), affecting different chromosomes in each cell (making it variegated) are found only in a certain number of cells (making it mosaic). MVA is characterized by various developmental defects and, despite its rarity, presents a unique clinical scenario to understand the consequences of chromosomal instability and copy number variation in humans. Research from patients with MVA, genetically engineered mouse models and functional cellular studies have found the genetic causes to be mutations in components of the spindle-assembly checkpoint as well as in related proteins involved in centrosome dynamics during mitosis. MVA is accompanied by tumour susceptibility (depending on the genetic basis) as well as cellular and systemic stress, including chronic immune response and the associated clinical implications.
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Affiliation(s)
- Marcos Malumbres
- Cancer Cell Cycle Group, Systems Oncology Program, Vall d'Hebron Institute of Oncology (VHIO), Vall d'Hebron Barcelona Hospital Campus, Barcelona, Spain.
- Cell Division and Cancer Group, Spanish National Cancer Research Centre (CNIO) Madrid, Madrid, Spain.
- Catalan Institution for Research and Advanced Studies (ICREA) Barcelona, Barcelona, Spain.
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4
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Hibino K, Sakai Y, Tamura S, Takagi M, Minami K, Natsume T, Shimazoe MA, Kanemaki MT, Imamoto N, Maeshima K. Single-nucleosome imaging unveils that condensins and nucleosome-nucleosome interactions differentially constrain chromatin to organize mitotic chromosomes. Nat Commun 2024; 15:7152. [PMID: 39169041 PMCID: PMC11339268 DOI: 10.1038/s41467-024-51454-y] [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: 07/05/2023] [Accepted: 08/08/2024] [Indexed: 08/23/2024] Open
Abstract
For accurate mitotic cell division, replicated chromatin must be assembled into chromosomes and faithfully segregated into daughter cells. While protein factors like condensin play key roles in this process, it is unclear how chromosome assembly proceeds as molecular events of nucleosomes in living cells and how condensins act on nucleosomes to organize chromosomes. To approach these questions, we investigate nucleosome behavior during mitosis of living human cells using single-nucleosome tracking, combined with rapid-protein depletion technology and computational modeling. Our results show that local nucleosome motion becomes increasingly constrained during mitotic chromosome assembly, which is functionally distinct from condensed apoptotic chromatin. Condensins act as molecular crosslinkers, locally constraining nucleosomes to organize chromosomes. Additionally, nucleosome-nucleosome interactions via histone tails constrain and compact whole chromosomes. Our findings elucidate the physical nature of the chromosome assembly process during mitosis.
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Affiliation(s)
- Kayo Hibino
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka, Japan
| | - Yuji Sakai
- Graduate School of Nanobioscience, Yokohama City University, Yokohama, Kanagawa, Japan
- Department of Biosystems Science, Institute for Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Sachiko Tamura
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Masatoshi Takagi
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Katsuhiko Minami
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka, Japan
| | - Toyoaki Natsume
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka, Japan
- Molecular Cell Engineering Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
- Research Center for Genome & Medical Sciences, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Masa A Shimazoe
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka, Japan
| | - Masato T Kanemaki
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka, Japan
- Molecular Cell Engineering Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan
- Graduate School of Medical Safety Management, Jikei University of Health Care Sciences, Osaka, Japan
| | - Kazuhiro Maeshima
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan.
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka, Japan.
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5
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Guérin TM, Barrington C, Pobegalov G, Molodtsov MI, Uhlmann F. An extrinsic motor directs chromatin loop formation by cohesin. EMBO J 2024:10.1038/s44318-024-00202-5. [PMID: 39160275 DOI: 10.1038/s44318-024-00202-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 07/30/2024] [Accepted: 07/31/2024] [Indexed: 08/21/2024] Open
Abstract
The ring-shaped cohesin complex topologically entraps two DNA molecules to establish sister chromatid cohesion. Cohesin also shapes the interphase chromatin landscape with wide-ranging implications for gene regulation, and cohesin is thought to achieve this by actively extruding DNA loops without topologically entrapping DNA. The 'loop extrusion' hypothesis finds motivation from in vitro observations-whether this process underlies in vivo chromatin loop formation remains untested. Here, using the budding yeast S. cerevisiae, we generate cohesin variants that have lost their ability to extrude DNA loops but retain their ability to topologically entrap DNA. Analysis of these variants suggests that in vivo chromatin loops form independently of loop extrusion. Instead, we find that transcription promotes loop formation, and acts as an extrinsic motor that expands these loops and defines their ultimate positions. Our results necessitate a re-evaluation of the loop extrusion hypothesis. We propose that cohesin, akin to sister chromatid cohesion establishment at replication forks, forms chromatin loops by DNA-DNA capture at places of transcription, thus unifying cohesin's two roles in chromosome segregation and interphase genome organisation.
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Affiliation(s)
- Thomas M Guérin
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
- Université Paris Cité and Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, Fontenay-aux-Roses, France
| | - Christopher Barrington
- Bioinformatics & Biostatistics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Georgii Pobegalov
- Mechanobiology and Biophysics Laboratory, The Francis Crick Institute, London, UK
- Department of Physics and Astronomy, University College London, London, UK
| | - Maxim I Molodtsov
- Mechanobiology and Biophysics Laboratory, The Francis Crick Institute, London, UK
- Department of Physics and Astronomy, University College London, London, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK.
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6
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Yao Q, Zhu L, Shi Z, Banerjee S, Chen C. Topoisomerase-modulated genome-wide DNA supercoiling domains colocalize with nuclear compartments and regulate human gene expression. Nat Struct Mol Biol 2024:10.1038/s41594-024-01377-5. [PMID: 39152238 DOI: 10.1038/s41594-024-01377-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 07/24/2024] [Indexed: 08/19/2024]
Abstract
DNA supercoiling is a biophysical feature of the double helix with a pivotal role in biological processes. However, understanding of DNA supercoiling in the chromatin remains limited. Here, we developed azide-trimethylpsoralen sequencing (ATMP-seq), a DNA supercoiling assay offering quantitative accuracy while minimizing genomic bias and background noise. Using ATMP-seq, we directly visualized transcription-dependent negative and positive twin-supercoiled domains around genes and mapped kilobase-resolution DNA supercoiling throughout the human genome. Remarkably, we discovered megabase-scale supercoiling domains (SDs) across all chromosomes that are modulated mainly by topoisomerases I and IIβ. Transcription activities, but not the consequent supercoiling accumulation in the local region, contribute to SD formation, indicating the long-range propagation of transcription-generated supercoiling. Genome-wide SDs colocalize with A/B compartments in both human and Drosophila cells but are distinct from topologically associating domains (TADs), with negative supercoiling accumulation at TAD boundaries. Furthermore, genome-wide DNA supercoiling varies between cell states and types and regulates human gene expression, underscoring the importance of supercoiling dynamics in chromatin regulation and function.
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Affiliation(s)
- Qian Yao
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Linying Zhu
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Zhen Shi
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Subhadra Banerjee
- Laboratory of Genome Integrity, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Chongyi Chen
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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7
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Bing X, Ke W, Fujioka M, Kurbidaeva A, Levitt S, Levine M, Schedl P, Jaynes JB. Chromosome structure in Drosophila is determined by boundary pairing not loop extrusion. eLife 2024; 13:RP94070. [PMID: 39110499 PMCID: PMC11305675 DOI: 10.7554/elife.94070] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2024] Open
Abstract
Two different models have been proposed to explain how the endpoints of chromatin looped domains ('TADs') in eukaryotic chromosomes are determined. In the first, a cohesin complex extrudes a loop until it encounters a boundary element roadblock, generating a stem-loop. In this model, boundaries are functionally autonomous: they have an intrinsic ability to halt the movement of incoming cohesin complexes that is independent of the properties of neighboring boundaries. In the second, loops are generated by boundary:boundary pairing. In this model, boundaries are functionally non-autonomous, and their ability to form a loop depends upon how well they match with their neighbors. Moreover, unlike the loop-extrusion model, pairing interactions can generate both stem-loops and circle-loops. We have used a combination of MicroC to analyze how TADs are organized, and experimental manipulations of the even skipped TAD boundary, homie, to test the predictions of the 'loop-extrusion' and the 'boundary-pairing' models. Our findings are incompatible with the loop-extrusion model, and instead suggest that the endpoints of TADs in flies are determined by a mechanism in which boundary elements physically pair with their partners, either head-to-head or head-to-tail, with varying degrees of specificity. Although our experiments do not address how partners find each other, the mechanism is unlikely to require loop extrusion.
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Affiliation(s)
- Xinyang Bing
- Lewis Sigler Institute, Princeton UniversityPrincetonUnited States
| | - Wenfan Ke
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - Miki Fujioka
- Department of Biochemistry and Molecular Biology, Thomas Jefferson UniversityPhiladelphiaUnited States
| | - Amina Kurbidaeva
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - Sarah Levitt
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - Mike Levine
- Lewis Sigler Institute, Princeton UniversityPrincetonUnited States
| | - Paul Schedl
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - James B Jaynes
- Department of Biochemistry and Molecular Biology, Thomas Jefferson UniversityPhiladelphiaUnited States
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8
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Ke W, Fujioka M, Schedl P, Jaynes JB. Stem-loop and circle-loop TADs generated by directional pairing of boundary elements have distinct physical and regulatory properties. eLife 2024; 13:RP94114. [PMID: 39110491 PMCID: PMC11305674 DOI: 10.7554/elife.94114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2024] Open
Abstract
The chromosomes in multicellular eukaryotes are organized into a series of topologically independent loops called TADs. In flies, TADs are formed by physical interactions between neighboring boundaries. Fly boundaries exhibit distinct partner preferences, and pairing interactions between boundaries are typically orientation-dependent. Pairing can be head-to-tail or head-to-head. The former generates a stem-loop TAD, while the latter gives a circle-loop TAD. The TAD that encompasses the Drosophila even skipped (eve) gene is formed by the head-to-tail pairing of the nhomie and homie boundaries. To explore the relationship between loop topology and the physical and regulatory landscape, we flanked the nhomie boundary region with two attP sites. The attP sites were then used to generate four boundary replacements: λ DNA, nhomie forward (WT orientation), nhomie reverse (opposite of WT orientation), and homie forward (same orientation as WT homie). The nhomie forward replacement restores the WT physical and regulatory landscape: in MicroC experiments, the eve TAD is a 'volcano' triangle topped by a plume, and the eve gene and its regulatory elements are sequestered from interactions with neighbors. The λ DNA replacement lacks boundary function: the endpoint of the 'new' eve TAD on the nhomie side is ill-defined, and eve stripe enhancers activate a nearby gene, eIF3j. While nhomie reverse and homie forward restore the eve TAD, the topology is a circle-loop, and this changes the local physical and regulatory landscape. In MicroC experiments, the eve TAD interacts with its neighbors, and the plume at the top of the eve triangle peak is converted to a pair of 'clouds' of contacts with the next-door TADs. Consistent with the loss of isolation afforded by the stem-loop topology, the eve enhancers weakly activate genes in the neighboring TADs. Conversely, eve function is partially disrupted.
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Affiliation(s)
- Wenfan Ke
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - Miki Fujioka
- Department of Biochemistry and Molecular Biology, Thomas Jefferson UniversityPhiladelphiaUnited States
| | - Paul Schedl
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - James B Jaynes
- Department of Biochemistry and Molecular Biology, Thomas Jefferson UniversityPhiladelphiaUnited States
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9
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Chou YC. Motor domain of condensin and step formation in extruding loop of DNA. J Biol Phys 2024:10.1007/s10867-024-09661-7. [PMID: 39078528 DOI: 10.1007/s10867-024-09661-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 07/07/2024] [Indexed: 07/31/2024] Open
Abstract
During the asymmetric loop extrusion of DNA by a condensin complex, one domain of the complex stably anchors to the DNA molecule, and another domain reels in the DNA strand into a loop. The DNA strand in the loop is fully relaxed, or there is no tension in the loop. Just outside of the loop, there is a tension that resists the extrusion of DNA. To maintain the extrusion of the DNA loop, the condensin complex must have a domain capable of generating a force to overcome the tension outside of the loop. This study proposes that the groove-shaped HEAT repeat domain Ycg1 plays the role of a molecular motor. A DNA molecule may bind to the groove electrostatically, and the weak binding force facilitates the random thermal motion of DNA molecules. A mechanical model that random collisions between DNA and the nonparallel inner surfaces of the groove may generate a directional force which is required for the loop extrusion to sustain. The hinge domain binds to the DNA molecule and acts as an anchor during asymmetric DNA loop extrusion. When the effects of ATP hydrolysis and the viscous drag of the fluid environment are considered, the motor-anchor model for the condensin complex and the mechanical model might explain the asymmetric loop extrusion, the formation of steps, the step size distribution in the loop extrusion, the tension-dependent extrusion speed, the interaction between coexisting loops on the DNA strand, and untying the knots during extrusion. This model can also explain the observed formation of the Z-loop.
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Affiliation(s)
- Ya-Chang Chou
- Department of Physics, National Tsing Hua University, Hsinchu, Taiwan, Republic of China.
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10
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Oldenkamp R, Rowland BD. Cell biology: Converging paths to cohesion. Curr Biol 2024; 34:R680-R682. [PMID: 39043139 DOI: 10.1016/j.cub.2024.05.060] [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: 07/25/2024]
Abstract
Cohesin holds together the sister chromatids from DNA replication onwards. How cohesion is established has long remained a black box. Through recent studies, a model is emerging in which a replisome-cohesin encounter results in the establishment of cohesive linkages at sites of replication termination.
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Affiliation(s)
- Roel Oldenkamp
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Benjamin D Rowland
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
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11
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Wang H, Ma B, Stevens T, Knapp J, Lu J, Prochownik EV. MYC Binding Near Transcriptional End Sites Regulates Basal Gene Expression, Read-Through Transcription and Intragenic Contacts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.11.603118. [PMID: 39071289 PMCID: PMC11275772 DOI: 10.1101/2024.07.11.603118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
The MYC oncoprotein regulates numerous genes involved in cellular processes such as cell cycle and mitochondrial and ribosomal structure and function. This requires heterodimerization with its partner, MAX, and binding to specific promoter and enhancer elements. Here, we show that MYC and MAX also bind near transcriptional end sites (TESs) of over one-sixth of all annotated genes. These interactions are dose-dependent, evolutionarily conserved, stabilize the normally short-lived MYC protein and regulate expression both in concert with and independent of MYC's binding elsewhere. MYC's TES binding occurs in association with other transcription factors, alters the chromatin landscape, increases nuclease susceptibility and can alter transcriptional read-through, particularly in response to certain stresses. MYC-bound TESs can directly contact promoters and may fine-tune gene expression in response to both physiologic and pathologic stimuli. Collectively, these findings support a previously unrecognized role for MYC in regulating transcription and its read-through via direct intragenic contacts between TESs and promoters.
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12
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Li J, Rohs R. Deep DNAshape webserver: prediction and real-time visualization of DNA shape considering extended k-mers. Nucleic Acids Res 2024; 52:W7-W12. [PMID: 38801070 PMCID: PMC11223853 DOI: 10.1093/nar/gkae433] [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: 02/26/2024] [Revised: 04/30/2024] [Accepted: 05/08/2024] [Indexed: 05/29/2024] Open
Abstract
Sequence-dependent DNA shape plays an important role in understanding protein-DNA binding mechanisms. High-throughput prediction of DNA shape features has become a valuable tool in the field of protein-DNA recognition, transcription factor-DNA binding specificity, and gene regulation. However, our widely used webserver, DNAshape, relies on statistically summarized pentamer query tables to query DNA shape features. These query tables do not consider flanking regions longer than two base pairs, and acquiring a query table for hexamers or higher-order k-mers is currently still unrealistic due to limitations in achieving sufficient statistical coverage in molecular simulations or structural biology experiments. A recent deep-learning method, Deep DNAshape, can predict DNA shape features at the core of a DNA fragment considering flanking regions of up to seven base pairs, trained on limited simulation data. However, Deep DNAshape is rather complicated to install, and it must run locally compared to the pentamer-based DNAshape webserver, creating a barrier for users. Here, we present the Deep DNAshape webserver, which has the benefits of both methods while being accurate, fast, and accessible to all users. Additional improvements of the webserver include the detection of user input in real time, the ability of interactive visualization tools and different modes of analyses. URL: https://deepdnashape.usc.edu.
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Affiliation(s)
- Jinsen Li
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
| | - Remo Rohs
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089, USA
- Thomas Lord Department of Computer Science, University of Southern California, Los Angeles, CA 90089, USA
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13
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Andrade Ruiz L, Kops GJPL, Sacristan C. Vertebrate centromere architecture: from chromatin threads to functional structures. Chromosoma 2024; 133:169-181. [PMID: 38856923 PMCID: PMC11266386 DOI: 10.1007/s00412-024-00823-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 05/21/2024] [Accepted: 05/27/2024] [Indexed: 06/11/2024]
Abstract
Centromeres are chromatin structures specialized in sister chromatid cohesion, kinetochore assembly, and microtubule attachment during chromosome segregation. The regional centromere of vertebrates consists of long regions of highly repetitive sequences occupied by the Histone H3 variant CENP-A, and which are flanked by pericentromeres. The three-dimensional organization of centromeric chromatin is paramount for its functionality and its ability to withstand spindle forces. Alongside CENP-A, key contributors to the folding of this structure include components of the Constitutive Centromere-Associated Network (CCAN), the protein CENP-B, and condensin and cohesin complexes. Despite its importance, the intricate architecture of the regional centromere of vertebrates remains largely unknown. Recent advancements in long-read sequencing, super-resolution and cryo-electron microscopy, and chromosome conformation capture techniques have significantly improved our understanding of this structure at various levels, from the linear arrangement of centromeric sequences and their epigenetic landscape to their higher-order compaction. In this review, we discuss the latest insights on centromere organization and place them in the context of recent findings describing a bipartite higher-order organization of the centromere.
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Affiliation(s)
- Lorena Andrade Ruiz
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands
- University Medical Center Utrecht, Utrecht, Netherlands
- Oncode Institute, Utrecht, Netherlands
| | - Geert J P L Kops
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands
- University Medical Center Utrecht, Utrecht, Netherlands
- Oncode Institute, Utrecht, Netherlands
| | - Carlos Sacristan
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands.
- University Medical Center Utrecht, Utrecht, Netherlands.
- Oncode Institute, Utrecht, Netherlands.
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14
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Wang B, Bian Q. Regulation of 3D genome organization during T cell activation. FEBS J 2024. [PMID: 38944686 DOI: 10.1111/febs.17211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 04/23/2024] [Accepted: 06/14/2024] [Indexed: 07/01/2024]
Abstract
Within the three-dimensional (3D) nuclear space, the genome organizes into a series of orderly structures that impose important influences on gene regulation. T lymphocytes, crucial players in adaptive immune responses, undergo intricate transcriptional remodeling upon activation, leading to differentiation into specific effector and memory T cell subsets. Recent evidence suggests that T cell activation is accompanied by dynamic changes in genome architecture at multiple levels, providing a unique biological context to explore the functional relevance and molecular mechanisms of 3D genome organization. Here, we summarize recent advances that link the reorganization of genome architecture to the remodeling of transcriptional programs and conversion of cell fates during T cell activation and differentiation. We further discuss how various chromatin architecture regulators, including CCCTC-binding factor and several transcription factors, collectively modulate the genome architecture during this process.
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Affiliation(s)
- Bao Wang
- Shanghai lnstitute of Precision Medicine, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, China
| | - Qian Bian
- Shanghai lnstitute of Precision Medicine, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, China
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15
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Pang QY, Chiu YC, Huang RYJ. Regulating epithelial-mesenchymal plasticity from 3D genome organization. Commun Biol 2024; 7:750. [PMID: 38902393 PMCID: PMC11190238 DOI: 10.1038/s42003-024-06441-w] [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: 09/26/2022] [Accepted: 06/11/2024] [Indexed: 06/22/2024] Open
Abstract
Epithelial-mesenchymal transition (EMT) is a dynamic process enabling polarized epithelial cells to acquire mesenchymal features implicated in development and carcinoma progression. As our understanding evolves, it is clear the reversible execution of EMT arises from complex epigenomic regulation involving histone modifications and 3-dimensional (3D) genome structural changes, leading to a cascade of transcriptional events. This review summarizes current knowledge on chromatin organization in EMT, with a focus on hierarchical structures of the 3D genome and chromatin accessibility changes.
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Affiliation(s)
- Qing You Pang
- Neuro-Oncology Research Laboratory, National Neuroscience Institute, Singapore, 308433, Singapore
| | - Yi-Chia Chiu
- School of Medicine, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Ruby Yun-Ju Huang
- School of Medicine, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan.
- Center for Advanced Computing and Imaging in Biomedicine, National Taiwan University, Taipei, 10051, Taiwan.
- Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119077, Singapore.
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16
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Li Q, Zhang J, Haluska C, Zhang X, Wang L, Liu G, Wang Z, Jin D, Cheng T, Wang H, Tian Y, Wang X, Sun L, Zhao X, Chen Z, Wang L. Cryo-EM structures of Smc5/6 in multiple states reveal its assembly and functional mechanisms. Nat Struct Mol Biol 2024:10.1038/s41594-024-01319-1. [PMID: 38890552 DOI: 10.1038/s41594-024-01319-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 04/17/2024] [Indexed: 06/20/2024]
Abstract
Smc5/6 is a member of the eukaryotic structural maintenance of chromosomes (SMC) family of complexes with important roles in genome maintenance and viral restriction. However, limited structural understanding of Smc5/6 hinders the elucidation of its diverse functions. Here, we report cryo-EM structures of the budding yeast Smc5/6 complex in eight-subunit, six-subunit and five-subunit states. Structural maps throughout the entire length of these complexes reveal modularity and key elements in complex assembly. We show that the non-SMC element (Nse)2 subunit supports the overall shape of the complex and uses a wedge motif to aid the stability and function of the complex. The Nse6 subunit features a flexible hook region for attachment to the Smc5 and Smc6 arm regions, contributing to the DNA repair roles of the complex. Our results also suggest a structural basis for the opposite effects of the Nse1-3-4 and Nse5-6 subcomplexes in regulating Smc5/6 ATPase activity. Collectively, our integrated structural and functional data provide a framework for understanding Smc5/6 assembly and function.
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Affiliation(s)
- Qian Li
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jun Zhang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Cory Haluska
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Xiang Zhang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) and Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Fifth People's Hospital, Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, School of Basic Medical Sciences,Fudan University, Shanghai, China
| | - Lei Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- CAS Key Laboratory of Infection and Immunity, National Laboratory of Macromolecules, Institute of Biophysics,Chinese Academy of Sciences, Beijing, China
| | - Guangfeng Liu
- National Center for Protein Science Shanghai, Shanghai Advanced Research Institute,Chinese Academy of Sciences, Shanghai, China
| | - Zhaoning Wang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Duo Jin
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Tong Cheng
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Hongxia Wang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
| | - Yuan Tian
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
| | - Xiangxi Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- CAS Key Laboratory of Infection and Immunity, National Laboratory of Macromolecules, Institute of Biophysics,Chinese Academy of Sciences, Beijing, China
| | - Lei Sun
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) and Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Fifth People's Hospital, Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, School of Basic Medical Sciences,Fudan University, Shanghai, China
| | - Xiaolan Zhao
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Zhenguo Chen
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) and Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Fifth People's Hospital, Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, School of Basic Medical Sciences,Fudan University, Shanghai, China.
| | - Lanfeng Wang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
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17
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Prevo B, Earnshaw WC. DNA packaging by molecular motors: from bacteriophage to human chromosomes. Nat Rev Genet 2024:10.1038/s41576-024-00740-y. [PMID: 38886215 DOI: 10.1038/s41576-024-00740-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2024] [Indexed: 06/20/2024]
Abstract
Dense packaging of genomic DNA is crucial for organismal survival, as DNA length always far exceeds the dimensions of the cells that contain it. Organisms, therefore, use sophisticated machineries to package their genomes. These systems range across kingdoms from a single ultra-powerful rotary motor that spools the DNA into a bacteriophage head, to hundreds of thousands of relatively weak molecular motors that coordinate the compaction of mitotic chromosomes in eukaryotic cells. Recent technological advances, such as DNA proximity-based sequencing approaches, polymer modelling and in vitro reconstitution of DNA loop extrusion, have shed light on the biological mechanisms driving DNA organization in different systems. Here, we discuss DNA packaging in bacteriophage, bacteria and eukaryotic cells, which, despite their extreme variation in size, structure and genomic content, all rely on the action of molecular motors to package their genomes.
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Affiliation(s)
- Bram Prevo
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK.
| | - William C Earnshaw
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK.
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18
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Vaculíková J, Holá M, Králová B, Lelkes E, Štefanovie B, Vágnerová R, Angelis KJ, Paleček JJ. NSE5 subunit interacts with distant regions of the SMC arms in the Physcomitrium patens SMC5/6 complex. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 38858852 DOI: 10.1111/tpj.16869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 05/21/2024] [Accepted: 05/25/2024] [Indexed: 06/12/2024]
Abstract
Structural maintenance of chromosome (SMC) complexes play roles in cohesion, condensation, replication, transcription, and DNA repair. Their cores are composed of SMC proteins with a unique structure consisting of an ATPase head, long arm, and hinge. SMC complexes form long rod-like structures, which can change to ring-like and elbow-bent conformations upon binding ATP, DNA, and other regulatory factors. These SMC dynamic conformational changes are involved in their loading, translocation, and DNA loop extrusion. Here, we examined the binding and role of the PpNSE5 regulatory factor of Physcomitrium patens PpSMC5/6 complex. We found that the PpNSE5 C-terminal half (aa230-505) is required for binding to its PpNSE6 partner, while the N-terminal half (aa1-230) binds PpSMC subunits. Specifically, the first 71 amino acids of PpNSE5 were required for binding to PpSMC6. Interestingly, the PpNSE5 binding required the PpSMC6 head-proximal joint region and PpSMC5 hinge-proximal arm, suggesting a long distance between binding sites on PpSMC5 and PpSMC6 arms. Therefore, we hypothesize that PpNSE5 either links two antiparallel SMC5/6 complexes or binds one SMC5/6 in elbow-bent conformation, the later model being consistent with the role of NSE5/NSE6 dimer as SMC5/6 loading factor to DNA lesions. In addition, we generated the P. patens Ppnse5KO1 mutant line with an N-terminally truncated version of PpNSE5, which exhibited DNA repair defects while keeping a normal number of rDNA repeats. As the first 71 amino acids of PpNSE5 are required for PpSMC6 binding, our results suggest the role of PpNSE5-PpSMC6 interaction in SMC5/6 loading to DNA lesions.
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Affiliation(s)
- Jitka Vaculíková
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
| | - Marcela Holá
- Institute of Experimental Botany Czech Academy of Sciences, Na Karlovce 1, 16000, Prague, Czech Republic
| | - Barbora Králová
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
| | - Edit Lelkes
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
| | - Barbora Štefanovie
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
| | - Radka Vágnerová
- Institute of Experimental Botany Czech Academy of Sciences, Na Karlovce 1, 16000, Prague, Czech Republic
| | - Karel J Angelis
- Institute of Experimental Botany Czech Academy of Sciences, Na Karlovce 1, 16000, Prague, Czech Republic
| | - Jan J Paleček
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
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19
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Prusén Mota I, Galova M, Schleiffer A, Nguyen TT, Kovacikova I, Farias Saad C, Litos G, Nishiyama T, Gregan J, Peters JM, Schlögelhofer P. Sororin is an evolutionary conserved antagonist of WAPL. Nat Commun 2024; 15:4729. [PMID: 38830897 PMCID: PMC11148194 DOI: 10.1038/s41467-024-49178-0] [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: 10/24/2022] [Accepted: 05/26/2024] [Indexed: 06/05/2024] Open
Abstract
Cohesin mediates sister chromatid cohesion to enable chromosome segregation and DNA damage repair. To perform these functions, cohesin needs to be protected from WAPL, which otherwise releases cohesin from DNA. It has been proposed that cohesin is protected from WAPL by SORORIN. However, in vivo evidence for this antagonism is missing and SORORIN is only known to exist in vertebrates and insects. It is therefore unknown how important and widespread SORORIN's functions are. Here we report the identification of SORORIN orthologs in Schizosaccharomyces pombe (Sor1) and Arabidopsis thaliana (AtSORORIN). sor1Δ mutants display cohesion defects, which are partially alleviated by wpl1Δ. Atsororin mutant plants display dwarfism, tissue specific cohesion defects and chromosome mis-segregation. Furthermore, Atsororin mutant plants are sterile and separate sister chromatids prematurely at anaphase I. The somatic, but not the meiotic deficiencies can be alleviated by loss of WAPL. These results provide in vivo evidence for SORORIN antagonizing WAPL, reveal that SORORIN is present in organisms beyond the animal kingdom and indicate that it has acquired tissue specific functions in plants.
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Affiliation(s)
- Ignacio Prusén Mota
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Vienna, Austria
- University of Vienna, Center for Molecular Biology, Department of Chromosome Biology, Vienna, Austria
- Vienna Biocenter PhD Program, a Doctoral School of the University of Vienna and the Medical University of Vienna, Vienna, Austria
| | - Marta Galova
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Alexander Schleiffer
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Tan-Trung Nguyen
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Vienna, Austria
- University of Vienna, Center for Molecular Biology, Department of Chromosome Biology, Vienna, Austria
| | - Ines Kovacikova
- University of Vienna, Center for Molecular Biology, Department of Chromosome Biology, Vienna, Austria
| | - Carolina Farias Saad
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Vienna, Austria
- University of Vienna, Center for Molecular Biology, Department of Chromosome Biology, Vienna, Austria
- Vienna Biocenter PhD Program, a Doctoral School of the University of Vienna and the Medical University of Vienna, Vienna, Austria
| | - Gabriele Litos
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Tomoko Nishiyama
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Juraj Gregan
- University of Vienna, Center for Molecular Biology, Department of Chromosome Biology, Vienna, Austria.
- Department of Applied Genetics and Cell Biology, Institute of Microbial Genetics, University of Natural Resources and Life Sciences, Tulln an der Donau, Austria.
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria.
| | - Peter Schlögelhofer
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Vienna, Austria.
- University of Vienna, Center for Molecular Biology, Department of Chromosome Biology, Vienna, Austria.
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20
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Magnitov M, de Wit E. Attraction and disruption: how loop extrusion and compartmentalisation shape the nuclear genome. Curr Opin Genet Dev 2024; 86:102194. [PMID: 38636335 PMCID: PMC11190842 DOI: 10.1016/j.gde.2024.102194] [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: 10/01/2023] [Revised: 03/21/2024] [Accepted: 03/31/2024] [Indexed: 04/20/2024]
Abstract
Chromatin loops, which bring two distal loci of the same chromosome into close physical proximity, are the ubiquitous units of the three-dimensional genome. Recent advances in understanding the spatial organisation of chromatin suggest that several distinct mechanisms control chromatin interactions, such as loop extrusion by cohesin complexes, compartmentalisation by phase separation, direct protein-protein interactions and others. Here, we review different types of chromatin loops and highlight the factors and processes involved in their regulation. We discuss how loop extrusion and compartmentalisation shape chromatin interactions and how these two processes can either positively or negatively influence each other.
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Affiliation(s)
- Mikhail Magnitov
- Division of Gene Regulation, the Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands. https://twitter.com/@MMagnitov
| | - Elzo de Wit
- Division of Gene Regulation, the Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands.
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21
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Yan L, Yuan X, Liu M, Chen Q, Zhang M, Xu J, Zeng LH, Zhang L, Huang J, Lu W, He X, Yan H, Wang F. A non-canonical role of the inner kinetochore in regulating sister-chromatid cohesion at centromeres. EMBO J 2024; 43:2424-2452. [PMID: 38714893 PMCID: PMC11182772 DOI: 10.1038/s44318-024-00104-6] [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: 09/21/2023] [Revised: 03/27/2024] [Accepted: 04/12/2024] [Indexed: 06/19/2024] Open
Abstract
The 16-subunit Constitutive Centromere-associated Network (CCAN)-based inner kinetochore is well-known for connecting centromeric chromatin to the spindle-binding outer kinetochore. Here, we report a non-canonical role for the inner kinetochore in directly regulating sister-chromatid cohesion at centromeres. We provide biochemical, X-ray crystal structure, and intracellular ectopic localization evidence that the inner kinetochore directly binds cohesin, a ring-shaped multi-subunit complex that holds sister chromatids together from S-phase until anaphase onset. This interaction is mediated by binding of the 5-subunit CENP-OPQUR sub-complex of CCAN to the Scc1-SA2 sub-complex of cohesin. Mutation in the CENP-U subunit of the CENP-OPQUR complex that abolishes its binding to the composite interface between Scc1 and SA2 weakens centromeric cohesion, leading to premature separation of sister chromatids during delayed metaphase. We further show that CENP-U competes with the cohesin release factor Wapl for binding the interface of Scc1-SA2, and that the cohesion-protecting role for CENP-U can be bypassed by depleting Wapl. Taken together, this study reveals an inner kinetochore-bound pool of cohesin, which strengthens centromeric sister-chromatid cohesion to resist metaphase spindle pulling forces.
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Affiliation(s)
- Lu Yan
- Life Sciences Institute, State Key Laboratory of Transvascular Implantation Devices of the Second Affiliated Hospital of Zhejiang University School of Medicine, MOE Laboratory of Biosystems Homeostasis and Protection, Zhejiang University, Hangzhou, 310058, China
| | - Xueying Yuan
- Life Sciences Institute, State Key Laboratory of Transvascular Implantation Devices of the Second Affiliated Hospital of Zhejiang University School of Medicine, MOE Laboratory of Biosystems Homeostasis and Protection, Zhejiang University, Hangzhou, 310058, China
| | - Mingjie Liu
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Qinfu Chen
- Department of Gynecological Oncology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
| | - Miao Zhang
- Life Sciences Institute, State Key Laboratory of Transvascular Implantation Devices of the Second Affiliated Hospital of Zhejiang University School of Medicine, MOE Laboratory of Biosystems Homeostasis and Protection, Zhejiang University, Hangzhou, 310058, China
| | - Junfen Xu
- Department of Gynecological Oncology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
| | - Ling-Hui Zeng
- Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, China
| | - Long Zhang
- Life Sciences Institute, State Key Laboratory of Transvascular Implantation Devices of the Second Affiliated Hospital of Zhejiang University School of Medicine, MOE Laboratory of Biosystems Homeostasis and Protection, Zhejiang University, Hangzhou, 310058, China
- Cancer Center, Zhejiang University, Hangzhou, 310058, China
| | - Jun Huang
- Life Sciences Institute, State Key Laboratory of Transvascular Implantation Devices of the Second Affiliated Hospital of Zhejiang University School of Medicine, MOE Laboratory of Biosystems Homeostasis and Protection, Zhejiang University, Hangzhou, 310058, China
- Cancer Center, Zhejiang University, Hangzhou, 310058, China
| | - Weiguo Lu
- Department of Gynecological Oncology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China
- Cancer Center, Zhejiang University, Hangzhou, 310058, China
| | - Xiaojing He
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China.
| | - Haiyan Yan
- Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, China.
| | - Fangwei Wang
- Life Sciences Institute, State Key Laboratory of Transvascular Implantation Devices of the Second Affiliated Hospital of Zhejiang University School of Medicine, MOE Laboratory of Biosystems Homeostasis and Protection, Zhejiang University, Hangzhou, 310058, China.
- Department of Gynecological Oncology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China.
- Cancer Center, Zhejiang University, Hangzhou, 310058, China.
- Zhejiang Provincial Key Laboratory of Geriatrics and Geriatrics Institute of Zhejiang Province, Affiliated Zhejiang Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.
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22
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Chan B, Rubinstein M. Activity-driven chromatin organization during interphase: Compaction, segregation, and entanglement suppression. Proc Natl Acad Sci U S A 2024; 121:e2401494121. [PMID: 38753513 PMCID: PMC11127048 DOI: 10.1073/pnas.2401494121] [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: 01/26/2024] [Accepted: 04/17/2024] [Indexed: 05/18/2024] Open
Abstract
In mammalian cells, the cohesin protein complex is believed to translocate along chromatin during interphase to form dynamic loops through a process called active loop extrusion. Chromosome conformation capture and imaging experiments have suggested that chromatin adopts a compact structure with limited interpenetration between chromosomes and between chromosomal sections. We developed a theory demonstrating that active loop extrusion causes the apparent fractal dimension of chromatin to cross-over between two and four at contour lengths on the order of 30 kilo-base pairs. The anomalously high fractal dimension [Formula: see text] is due to the inability of extruded loops to fully relax during active extrusion. Compaction on longer contour length scales extends within topologically associated domains (TADs), facilitating gene regulation by distal elements. Extrusion-induced compaction segregates TADs such that overlaps between TADs are reduced to less than 35% and increases the entanglement strand of chromatin by up to a factor of 50 to several Mega-base pairs. Furthermore, active loop extrusion couples cohesin motion to chromatin conformations formed by previously extruding cohesins and causes the mean square displacement of chromatin loci during lag times ([Formula: see text]) longer than tens of minutes to be proportional to [Formula: see text]. We validate our results with hybrid molecular dynamics-Monte Carlo simulations and show that our theory is consistent with experimental data. This work provides a theoretical basis for the compact organization of interphase chromatin, explaining the physical reason for TAD segregation and suppression of chromatin entanglements which contribute to efficient gene regulation.
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Affiliation(s)
- Brian Chan
- Department of Biomedical Engineering, Duke University, Durham, NC27708
| | - Michael Rubinstein
- Department of Biomedical Engineering, Duke University, Durham, NC27708
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC27708
- Department of Physics, Duke University, Durham, NC27708
- Department of Chemistry, Duke University, Durham, NC27708
- World Premier International Research Center Initiative–Institute for Chemical Reaction Design and Discovery, Hokkaido University, Sapporo001-0021, Japan
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23
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Kant A, Guo Z, Vinayak V, Neguembor MV, Li WS, Agrawal V, Pujadas E, Almassalha L, Backman V, Lakadamyali M, Cosma MP, Shenoy VB. Active transcription and epigenetic reactions synergistically regulate meso-scale genomic organization. Nat Commun 2024; 15:4338. [PMID: 38773126 PMCID: PMC11109243 DOI: 10.1038/s41467-024-48698-z] [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: 04/24/2023] [Accepted: 05/06/2024] [Indexed: 05/23/2024] Open
Abstract
In interphase nuclei, chromatin forms dense domains of characteristic sizes, but the influence of transcription and histone modifications on domain size is not understood. We present a theoretical model exploring this relationship, considering chromatin-chromatin interactions, histone modifications, and chromatin extrusion. We predict that the size of heterochromatic domains is governed by a balance among the diffusive flux of methylated histones sustaining them and the acetylation reactions in the domains and the process of loop extrusion via supercoiling by RNAPII at their periphery, which contributes to size reduction. Super-resolution and nano-imaging of five distinct cell lines confirm the predictions indicating that the absence of transcription leads to larger heterochromatin domains. Furthermore, the model accurately reproduces the findings regarding how transcription-mediated supercoiling loss can mitigate the impacts of excessive cohesin loading. Our findings shed light on the role of transcription in genome organization, offering insights into chromatin dynamics and potential therapeutic targets.
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Affiliation(s)
- Aayush Kant
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Zixian Guo
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Vinayak Vinayak
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Maria Victoria Neguembor
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003, Barcelona, Spain
| | - Wing Shun Li
- Department of Applied Physics, Northwestern University, Evanston, IL, 60208, USA
- Center for Physical Genomics and Engineering, Northwestern University, Evanston, IL, 60202, USA
| | - Vasundhara Agrawal
- Center for Physical Genomics and Engineering, Northwestern University, Evanston, IL, 60202, USA
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Emily Pujadas
- Center for Physical Genomics and Engineering, Northwestern University, Evanston, IL, 60202, USA
| | - Luay Almassalha
- Center for Physical Genomics and Engineering, Northwestern University, Evanston, IL, 60202, USA
- Department of Gastroenterology and Hepatology, Northwestern Memorial Hospital, Chicago, IL, 60611, USA
| | - Vadim Backman
- Center for Physical Genomics and Engineering, Northwestern University, Evanston, IL, 60202, USA
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Melike Lakadamyali
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Maria Pia Cosma
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003, Barcelona, Spain
- ICREA, Barcelona, 08010, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, 08003, Spain
| | - Vivek B Shenoy
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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24
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Liu C, Nagashima H, Fernando N, Bass V, Gopalakrishnan J, Signorella S, Montgomery W, Lim AI, Harrison O, Reich L, Yao C, Sun HW, Brooks SR, Jiang K, Nagarajan V, Zhao Y, Jung S, Phillips R, Mikami Y, Lareau CA, Kanno Y, Jankovic D, Aryee MJ, Pękowska A, Belkaid Y, O'Shea J, Shih HY. A CTCF-binding site in the Mdm1-Il22-Ifng locus shapes cytokine expression profiles and plays a critical role in early Th1 cell fate specification. Immunity 2024; 57:1005-1018.e7. [PMID: 38697116 PMCID: PMC11108081 DOI: 10.1016/j.immuni.2024.04.007] [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: 10/31/2022] [Revised: 12/12/2023] [Accepted: 04/10/2024] [Indexed: 05/04/2024]
Abstract
Cytokine expression during T cell differentiation is a highly regulated process that involves long-range promoter-enhancer and CTCF-CTCF contacts at cytokine loci. Here, we investigated the impact of dynamic chromatin loop formation within the topologically associating domain (TAD) in regulating the expression of interferon gamma (IFN-γ) and interleukin-22 (IL-22); these cytokine loci are closely located in the genome and are associated with complex enhancer landscapes, which are selectively active in type 1 and type 3 lymphocytes. In situ Hi-C analyses revealed inducible TADs that insulated Ifng and Il22 enhancers during Th1 cell differentiation. Targeted deletion of a 17 bp boundary motif of these TADs imbalanced Th1- and Th17-associated immunity, both in vitro and in vivo, upon Toxoplasma gondii infection. In contrast, this boundary element was dispensable for cytokine regulation in natural killer cells. Our findings suggest that precise cytokine regulation relies on lineage- and developmental stage-specific interactions of 3D chromatin architectures and enhancer landscapes.
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Affiliation(s)
- Chunhong Liu
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hiroyuki Nagashima
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nilisha Fernando
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Victor Bass
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jaanam Gopalakrishnan
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sadie Signorella
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA; Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Will Montgomery
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ai Ing Lim
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Oliver Harrison
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lauren Reich
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Chen Yao
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hong-Wei Sun
- Biodata Mining and Discovery Section, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephen R Brooks
- Biodata Mining and Discovery Section, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kan Jiang
- Biodata Mining and Discovery Section, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Vijayaraj Nagarajan
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yongbing Zhao
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Seolkyoung Jung
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rachael Phillips
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yohei Mikami
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Caleb A Lareau
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Yuka Kanno
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dragana Jankovic
- Immunoparasitology Unit, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Martin J Aryee
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Aleksandra Pękowska
- Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Yasmine Belkaid
- Metaorganism Immunity Section, Laboratory of Host Immunity and Microbiome, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - John O'Shea
- Lymphocyte Cell Biology Section, Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Han-Yu Shih
- Neuro-Immune Regulome Unit, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA; National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
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25
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Guo R, Dong X, Chen F, Ji T, He Q, Zhang J, Sheng Y, Liu Y, Yang S, Liang W, Song Y, Fang K, Zhang L, Hu G, Yao H. TEAD2 initiates ground-state pluripotency by mediating chromatin looping. EMBO J 2024; 43:1965-1989. [PMID: 38605224 PMCID: PMC11099042 DOI: 10.1038/s44318-024-00086-5] [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: 06/25/2023] [Revised: 02/26/2024] [Accepted: 03/03/2024] [Indexed: 04/13/2024] Open
Abstract
The transition of mouse embryonic stem cells (ESCs) between serum/LIF and 2i(MEK and GSK3 kinase inhibitor)/LIF culture conditions serves as a valuable model for exploring the mechanisms underlying ground and confused pluripotent states. Regulatory networks comprising core and ancillary pluripotency factors drive the gene expression programs defining stable naïve pluripotency. In our study, we systematically screened factors essential for ESC pluripotency, identifying TEAD2 as an ancillary factor maintaining ground-state pluripotency in 2i/LIF ESCs and facilitating the transition from serum/LIF to 2i/LIF ESCs. TEAD2 exhibits increased binding to chromatin in 2i/LIF ESCs, targeting active chromatin regions to regulate the expression of 2i-specific genes. In addition, TEAD2 facilitates the expression of 2i-specific genes by mediating enhancer-promoter interactions during the serum/LIF to 2i/LIF transition. Notably, deletion of Tead2 results in reduction of a specific set of enhancer-promoter interactions without significantly affecting binding of chromatin architecture proteins, CCCTC-binding factor (CTCF), and Yin Yang 1 (YY1). In summary, our findings highlight a novel prominent role of TEAD2 in orchestrating higher-order chromatin structures of 2i-specific genes to sustain ground-state pluripotency.
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Affiliation(s)
- Rong Guo
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xiaotao Dong
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- School of Basic Medical Science, Henan University, Kaifeng, China
| | - Feng Chen
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
| | - Tianrong Ji
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Qiannan He
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Jie Zhang
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Yingliang Sheng
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Yanjiang Liu
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Shengxiong Yang
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Weifang Liang
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong, China
| | - Yawei Song
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Ke Fang
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Lingling Zhang
- Institute of Clinical Pharmacology, Anhui Medical University, Hefei, China
| | - Gongcheng Hu
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Hongjie Yao
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China.
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
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26
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Wright NE, Kennedy DE, Ai J, Veselits ML, Attaway M, Yoon YM, Durkee MS, Veselits J, Maienschein-Cline M, Mandal M, Clark MR. BRWD1 establishes epigenetic states for germinal center initiation, maintenance, and function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.25.591154. [PMID: 38712068 PMCID: PMC11071454 DOI: 10.1101/2024.04.25.591154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Germinal center (GC) B cells segregate into three subsets that compartmentalize the antagonistic molecular programs of selection, proliferation, and somatic hypermutation. In bone marrow, the epigenetic reader BRWD1 orchestrates and insulates the sequential stages of cell proliferation and Igk recombination. We hypothesized BRWD1 might play similar insulative roles in the periphery. In Brwd1 -/- follicular B cells, GC initiation and class switch recombination following immunization were inhibited. In contrast, in Brwd1 -/- GC B cells there was admixing of chromatin accessibility across GC subsets and transcriptional dysregulation including induction of inflammatory pathways. This global molecular GC dysregulation was associated with specific defects in proliferation, affinity maturation, and tolerance. These data suggest that GC subset identity is required for some but not all GC-attributed functions. Furthermore, these data demonstrate a central role for BRWD1 in orchestrating epigenetic transitions at multiple steps along B cell developmental and activation pathways.
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27
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Brown JL, Zhang L, Rocha PP, Kassis JA, Sun MA. Polycomb protein binding and looping in the ON transcriptional state. SCIENCE ADVANCES 2024; 10:eadn1837. [PMID: 38657072 PMCID: PMC11042752 DOI: 10.1126/sciadv.adn1837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 03/22/2024] [Indexed: 04/26/2024]
Abstract
Polycomb group (PcG) proteins mediate epigenetic silencing of important developmental genes by modifying histones and compacting chromatin through two major protein complexes, PRC1 and PRC2. These complexes are recruited to DNA by CpG islands (CGIs) in mammals and Polycomb response elements (PREs) in Drosophila. When PcG target genes are turned OFF, PcG proteins bind to PREs or CGIs, and PREs serve as anchors that loop together and stabilize gene silencing. Here, we address which PcG proteins bind to PREs and whether PREs mediate looping when their targets are in the ON transcriptional state. While the binding of most PcG proteins decreases at PREs in the ON state, one PRC1 component, Ph, remains bound. Further, PREs can loop to each other and with presumptive enhancers in the ON state and, like CGIs, may act as tethering elements between promoters and enhancers. Overall, our data suggest that PREs are important looping elements for developmental loci in both the ON and OFF states.
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Affiliation(s)
- J. Lesley Brown
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Liangliang Zhang
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Pedro P. Rocha
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
- National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Judith A. Kassis
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ming-an Sun
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, Jiangsu, China
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28
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Raimer Young HM, Hou PC, Bartosik AR, Atkin ND, Wang L, Wang Z, Ratan A, Zang C, Wang YH. DNA fragility at topologically associated domain boundaries is promoted by alternative DNA secondary structure and topoisomerase II activity. Nucleic Acids Res 2024; 52:3837-3855. [PMID: 38452213 DOI: 10.1093/nar/gkae164] [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: 08/15/2023] [Revised: 02/03/2024] [Accepted: 02/23/2024] [Indexed: 03/09/2024] Open
Abstract
CCCTC-binding factor (CTCF) binding sites are hotspots of genome instability. Although many factors have been associated with CTCF binding site fragility, no study has integrated all fragility-related factors to understand the mechanism(s) of how they work together. Using an unbiased, genome-wide approach, we found that DNA double-strand breaks (DSBs) are enriched at strong, but not weak, CTCF binding sites in five human cell types. Energetically favorable alternative DNA secondary structures underlie strong CTCF binding sites. These structures coincided with the location of topoisomerase II (TOP2) cleavage complex, suggesting that DNA secondary structure acts as a recognition sequence for TOP2 binding and cleavage at CTCF binding sites. Furthermore, CTCF knockdown significantly increased DSBs at strong CTCF binding sites and at CTCF sites that are located at topologically associated domain (TAD) boundaries. TAD boundary-associated CTCF sites that lost CTCF upon knockdown displayed increased DSBs when compared to the gained sites, and those lost sites are overrepresented with G-quadruplexes, suggesting that the structures act as boundary insulators in the absence of CTCF, and contribute to increased DSBs. These results model how alternative DNA secondary structures facilitate recruitment of TOP2 to CTCF binding sites, providing mechanistic insight into DNA fragility at CTCF binding sites.
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Affiliation(s)
- Heather M Raimer Young
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908-0733, USA
| | - Pei-Chi Hou
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908-0733, USA
| | - Anna R Bartosik
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908-0733, USA
| | - Naomi D Atkin
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908-0733, USA
| | - Lixin Wang
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
| | - Zhenjia Wang
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA 22908-0717, USA
| | - Aakrosh Ratan
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908-0733, USA
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA 22908-0717, USA
- Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
- University of Virginia Comprehensive Cancer Center, Charlottesville, VA 22908, USA
| | - Chongzhi Zang
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908-0733, USA
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA 22908-0717, USA
- Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
- University of Virginia Comprehensive Cancer Center, Charlottesville, VA 22908, USA
| | - Yuh-Hwa Wang
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908-0733, USA
- University of Virginia Comprehensive Cancer Center, Charlottesville, VA 22908, USA
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29
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Oberbeckmann E, Oudelaar AM. Genome organization across scales: mechanistic insights from in vitro reconstitution studies. Biochem Soc Trans 2024; 52:793-802. [PMID: 38451192 PMCID: PMC11088924 DOI: 10.1042/bst20230883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/19/2024] [Accepted: 02/27/2024] [Indexed: 03/08/2024]
Abstract
Eukaryotic genomes are compacted and organized into distinct three-dimensional (3D) structures, which range from small-scale nucleosome arrays to large-scale chromatin domains. These chromatin structures play an important role in the regulation of transcription and other nuclear processes. The molecular mechanisms that drive the formation of chromatin structures across scales and the relationship between chromatin structure and function remain incompletely understood. Because the processes involved are complex and interconnected, it is often challenging to dissect the underlying principles in the nuclear environment. Therefore, in vitro reconstitution systems provide a valuable approach to gain insight into the molecular mechanisms by which chromatin structures are formed and to determine the cause-consequence relationships between the processes involved. In this review, we give an overview of in vitro approaches that have been used to study chromatin structures across scales and how they have increased our understanding of the formation and function of these structures. We start by discussing in vitro studies that have given insight into the mechanisms of nucleosome positioning. Next, we discuss recent efforts to reconstitute larger-scale chromatin domains and loops and the resulting insights into the principles of genome organization. We conclude with an outlook on potential future applications of chromatin reconstitution systems and how they may contribute to answering open questions concerning chromatin architecture.
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Affiliation(s)
- Elisa Oberbeckmann
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - A. Marieke Oudelaar
- Genome Organization and Regulation, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
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30
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Kim KL, Rahme GJ, Goel VY, El Farran CA, Hansen AS, Bernstein BE. Dissection of a CTCF topological boundary uncovers principles of enhancer-oncogene regulation. Mol Cell 2024; 84:1365-1376.e7. [PMID: 38452764 PMCID: PMC10997458 DOI: 10.1016/j.molcel.2024.02.007] [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: 10/03/2023] [Revised: 01/03/2024] [Accepted: 02/08/2024] [Indexed: 03/09/2024]
Abstract
Enhancer-gene communication is dependent on topologically associating domains (TADs) and boundaries enforced by the CCCTC-binding factor (CTCF) insulator, but the underlying structures and mechanisms remain controversial. Here, we investigate a boundary that typically insulates fibroblast growth factor (FGF) oncogenes but is disrupted by DNA hypermethylation in gastrointestinal stromal tumors (GISTs). The boundary contains an array of CTCF sites that enforce adjacent TADs, one containing FGF genes and the other containing ANO1 and its putative enhancers, which are specifically active in GIST and its likely cell of origin. We show that coordinate disruption of four CTCF motifs in the boundary fuses the adjacent TADs, allows the ANO1 enhancer to contact FGF3, and causes its robust induction. High-resolution micro-C maps reveal specific contact between transcription initiation sites in the ANO1 enhancer and FGF3 promoter that quantitatively scales with FGF3 induction such that modest changes in contact frequency result in strong changes in expression, consistent with a causal relationship.
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Affiliation(s)
- Kyung Lock Kim
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Departments of Cell Biology and Pathology, Harvard Medical School, Boston, MA 02215, USA
| | - Gilbert J Rahme
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Departments of Cell Biology and Pathology, Harvard Medical School, Boston, MA 02215, USA
| | - Viraat Y Goel
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, Cambridge, MA 02139, USA
| | - Chadi A El Farran
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Departments of Cell Biology and Pathology, Harvard Medical School, Boston, MA 02215, USA
| | - Anders S Hansen
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, Cambridge, MA 02139, USA
| | - Bradley E Bernstein
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Departments of Cell Biology and Pathology, Harvard Medical School, Boston, MA 02215, USA.
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31
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Golov AK, Gavrilov AA. Cohesin-Dependent Loop Extrusion: Molecular Mechanics and Role in Cell Physiology. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:601-625. [PMID: 38831499 DOI: 10.1134/s0006297924040023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/29/2023] [Accepted: 02/15/2024] [Indexed: 06/05/2024]
Abstract
The most prominent representatives of multisubunit SMC complexes, cohesin and condensin, are best known as structural components of mitotic chromosomes. It turned out that these complexes, as well as their bacterial homologues, are molecular motors, the ATP-dependent movement of these complexes along DNA threads leads to the formation of DNA loops. In recent years, we have witnessed an avalanche-like accumulation of data on the process of SMC dependent DNA looping, also known as loop extrusion. This review briefly summarizes the current understanding of the place and role of cohesin-dependent extrusion in cell physiology and presents a number of models describing the potential molecular mechanism of extrusion in a most compelling way. We conclude the review with a discussion of how the capacity of cohesin to extrude DNA loops may be mechanistically linked to its involvement in sister chromatid cohesion.
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Affiliation(s)
- Arkadiy K Golov
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia.
- Technion - Israel Institute of Technology, Haifa, 3525433, Israel
| | - Alexey A Gavrilov
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia.
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32
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Han MH, Park J, Park M. Advances in the multimodal analysis of the 3D chromatin structure and gene regulation. Exp Mol Med 2024; 56:763-771. [PMID: 38658704 PMCID: PMC11059362 DOI: 10.1038/s12276-024-01246-7] [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: 11/20/2023] [Revised: 04/03/2024] [Accepted: 04/08/2024] [Indexed: 04/26/2024] Open
Abstract
Recent studies have demonstrated that the three-dimensional conformation of the chromatin plays a crucial role in gene regulation, with aberrations potentially leading to various diseases. Advanced methodologies have revealed a link between the chromatin conformation and biological function. This review divides these methodologies into sequencing-based and imaging-based methodologies, tracing their development over time. We particularly highlight innovative techniques that facilitate the simultaneous mapping of RNAs, histone modifications, and proteins within the context of the 3D architecture of chromatin. This multimodal integration substantially improves our ability to establish a robust connection between the spatial arrangement of molecular components in the nucleus and their functional roles. Achieving a comprehensive understanding of gene regulation requires capturing diverse data modalities within individual cells, enabling the direct inference of functional relationships between these components. In this context, imaging-based technologies have emerged as an especially promising approach for gathering spatial information across multiple components in the same cell.
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Affiliation(s)
- Man-Hyuk Han
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Jihyun Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Minhee Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- Graduate School of Engineering Biology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- KAIST Institute for BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- KAIST Stem Cell Center, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
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33
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Rittenhouse NL, Dowen JM. Cohesin regulation and roles in chromosome structure and function. Curr Opin Genet Dev 2024; 85:102159. [PMID: 38382406 PMCID: PMC10947815 DOI: 10.1016/j.gde.2024.102159] [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: 09/12/2023] [Revised: 01/22/2024] [Accepted: 01/27/2024] [Indexed: 02/23/2024]
Abstract
Chromosome structure regulates DNA-templated processes such as transcription of genes. Dynamic changes to chromosome structure occur during development and in disease contexts. The cohesin complex is a molecular motor that regulates chromosome structure by generating DNA loops that bring two distal genomic sites into close spatial proximity. There are many open questions regarding the formation and dissolution of DNA loops, as well as the role(s) of DNA loops in regulating transcription of the interphase genome. This review focuses on recent discoveries that provide molecular insights into the role of cohesin and chromosome structure in gene transcription during development and disease.
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Affiliation(s)
- Natalie L Rittenhouse
- Curriculum in Genetics & Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jill M Dowen
- Department of Biophysics & Biochemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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34
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Golov AK, Gavrilov AA. Cohesin Complex: Structure and Principles of Interaction with DNA. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:585-600. [PMID: 38831498 DOI: 10.1134/s0006297924040011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 02/19/2024] [Accepted: 02/23/2024] [Indexed: 06/05/2024]
Abstract
Accurate duplication and separation of long linear genomic DNA molecules is associated with a number of purely mechanical problems. SMC complexes are key components of the cellular machinery that ensures decatenation of sister chromosomes and compaction of genomic DNA during division. Cohesin, one of the essential eukaryotic SMC complexes, has a typical ring structure with intersubunit pore through which DNA molecules can be threaded. Capacity of cohesin for such topological entrapment of DNA is crucial for the phenomenon of post-replicative association of sister chromatids better known as cohesion. Recently, it became apparent that cohesin and other SMC complexes are, in fact, motor proteins with a very peculiar movement pattern leading to formation of DNA loops. This specific process has been called loop extrusion. Extrusion underlies multiple functions of cohesin beyond cohesion, but molecular mechanism of the process remains a mystery. In this review, we summarized the data on molecular architecture of cohesin, effect of ATP hydrolysis cycle on this architecture, and known modes of cohesin-DNA interactions. Many of the seemingly disparate facts presented here will probably be incorporated in a unified mechanistic model of loop extrusion in the not-so-distant future.
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Affiliation(s)
- Arkadiy K Golov
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia.
- Technion - Israel Institute of Technology, Haifa, 3525433, Israel
| | - Alexey A Gavrilov
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia.
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35
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Eustermann S, Patel AB, Hopfner KP, He Y, Korber P. Energy-driven genome regulation by ATP-dependent chromatin remodellers. Nat Rev Mol Cell Biol 2024; 25:309-332. [PMID: 38081975 DOI: 10.1038/s41580-023-00683-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2023] [Indexed: 03/28/2024]
Abstract
The packaging of DNA into chromatin in eukaryotes regulates gene transcription, DNA replication and DNA repair. ATP-dependent chromatin remodelling enzymes (re)arrange nucleosomes at the first level of chromatin organization. Their Snf2-type motor ATPases alter histone-DNA interactions through a common DNA translocation mechanism. Whether remodeller activities mainly catalyse nucleosome dynamics or accurately co-determine nucleosome organization remained unclear. In this Review, we discuss the emerging mechanisms of chromatin remodelling: dynamic remodeller architectures and their interactions, the inner workings of the ATPase cycle, allosteric regulation and pathological dysregulation. Recent mechanistic insights argue for a decisive role of remodellers in the energy-driven self-organization of chromatin, which enables both stability and plasticity of genome regulation - for example, during development and stress. Different remodellers, such as members of the SWI/SNF, ISWI, CHD and INO80 families, process (epi)genetic information through specific mechanisms into distinct functional outputs. Combinatorial assembly of remodellers and their interplay with histone modifications, histone variants, DNA sequence or DNA-bound transcription factors regulate nucleosome mobilization or eviction or histone exchange. Such input-output relationships determine specific nucleosome positions and compositions with distinct DNA accessibilities and mediate differential genome regulation. Finally, remodeller genes are often mutated in diseases characterized by genome dysregulation, notably in cancer, and we discuss their physiological relevance.
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Affiliation(s)
- Sebastian Eustermann
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Avinash B Patel
- Department of Molecular Biosciences, Robert H. Lurie Comprehensive Cancer Center, Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| | - Karl-Peter Hopfner
- Gene Center and Department of Biochemistry, Faculty of Chemistry and Pharmacy, LMU Munich, Munich, Germany
| | - Yuan He
- Department of Molecular Biosciences, Robert H. Lurie Comprehensive Cancer Center, Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA.
| | - Philipp Korber
- Biomedical Center (BMC), Molecular Biology, Faculty of Medicine, LMU Munich, Martinsried, Germany.
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36
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Friedman MJ, Wagner T, Lee H, Rosenfeld MG, Oh S. Enhancer-promoter specificity in gene transcription: molecular mechanisms and disease associations. Exp Mol Med 2024; 56:772-787. [PMID: 38658702 PMCID: PMC11058250 DOI: 10.1038/s12276-024-01233-y] [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: 11/26/2023] [Revised: 02/28/2024] [Accepted: 03/05/2024] [Indexed: 04/26/2024] Open
Abstract
Although often located at a distance from their target gene promoters, enhancers are the primary genomic determinants of temporal and spatial transcriptional specificity in metazoans. Since the discovery of the first enhancer element in simian virus 40, there has been substantial interest in unraveling the mechanism(s) by which enhancers communicate with their partner promoters to ensure proper gene expression. These research efforts have benefited considerably from the application of increasingly sophisticated sequencing- and imaging-based approaches in conjunction with innovative (epi)genome-editing technologies; however, despite various proposed models, the principles of enhancer-promoter interaction have still not been fully elucidated. In this review, we provide an overview of recent progress in the eukaryotic gene transcription field pertaining to enhancer-promoter specificity. A better understanding of the mechanistic basis of lineage- and context-dependent enhancer-promoter engagement, along with the continued identification of functional enhancers, will provide key insights into the spatiotemporal control of gene expression that can reveal therapeutic opportunities for a range of enhancer-related diseases.
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Affiliation(s)
- Meyer J Friedman
- Department and School of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Tobias Wagner
- Department and School of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Haram Lee
- College of Pharmacy Korea University, 2511 Sejong-ro, Sejong, 30019, Republic of Korea
| | - Michael G Rosenfeld
- Department and School of Medicine, University of California, San Diego, La Jolla, CA, USA.
| | - Soohwan Oh
- College of Pharmacy Korea University, 2511 Sejong-ro, Sejong, 30019, Republic of Korea.
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37
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Yuan T, Yan H, Bailey MLP, Williams JF, Surovtsev I, King MC, Mochrie SGJ. Effect of loops on the mean-square displacement of Rouse-model chromatin. Phys Rev E 2024; 109:044502. [PMID: 38755928 DOI: 10.1103/physreve.109.044502] [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: 04/24/2023] [Accepted: 02/16/2024] [Indexed: 05/18/2024]
Abstract
Chromatin polymer dynamics are commonly described using the classical Rouse model. The subsequent discovery, however, of intermediate-scale chromatin organization known as topologically associating domains (TADs) in experimental Hi-C contact maps for chromosomes across the tree of life, together with the success of loop extrusion factor (LEF) model in explaining TAD formation, motivates efforts to understand the effect of loops and loop extrusion on chromatin dynamics. This paper seeks to fulfill this need by combining LEF-model simulations with extended Rouse-model polymer simulations to investigate the dynamics of chromatin with loops and dynamic loop extrusion. We show that loops significantly suppress the averaged mean-square displacement (MSD) of a gene locus, consistent with recent experiments that track fluorescently labeled chromatin loci. We also find that loops reduce the MSD's stretching exponent from the classical Rouse-model value of 1/2 to a loop-density-dependent value in the 0.45-0.40 range. Remarkably, stretching exponent values in this range have also been observed in recent experiments [Weber et al., Phys. Rev. Lett. 104, 238102 (2010)0031-900710.1103/PhysRevLett.104.238102; Bailey et al., Mol. Biol. Cell 34, ar78 (2023)1059-152410.1091/mbc.E23-04-0119]. We also show that the dynamics of loop extrusion itself negligibly affects chromatin mobility. By studying static "rosette" loop configurations, we also demonstrate that chromatin MSDs and stretching exponents depend on the location of the locus in question relative to the position of the loops and on the local friction environment.
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Affiliation(s)
- Tianyu Yuan
- Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, Connecticut 06520, USA
- Department of Physics, Yale University, New Haven, Connecticut 06520, USA
| | - Hao Yan
- Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, Connecticut 06520, USA
- Department of Physics, Yale University, New Haven, Connecticut 06520, USA
| | - Mary Lou P Bailey
- Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, Connecticut 06520, USA
- Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA
| | - Jessica F Williams
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06520, USA
| | - Ivan Surovtsev
- Department of Physics, Yale University, New Haven, Connecticut 06520, USA
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06520, USA
| | - Megan C King
- Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, Connecticut 06520, USA
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06520, USA
- Department of Molecular, Cell and Developmental Biology, Yale University, New Haven, Connecticut 06511, USA
| | - Simon G J Mochrie
- Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, Connecticut 06520, USA
- Department of Physics, Yale University, New Haven, Connecticut 06520, USA
- Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA
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38
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Tong Z, Zhang Y, Guo P, Wang W, Chen Q, Jin J, Liu S, Yu C, Mo P, Zhang L, Huang J. Steroid receptor coactivator 1 promotes human hepatocellular carcinoma invasiveness through enhancing MMP-9. J Cell Mol Med 2024; 28:e18171. [PMID: 38506084 PMCID: PMC10951881 DOI: 10.1111/jcmm.18171] [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: 06/26/2023] [Revised: 01/23/2024] [Accepted: 01/31/2024] [Indexed: 03/21/2024] Open
Abstract
SRC-1 functions as a transcriptional coactivator for steroid receptors and various transcriptional factors. Notably, SRC-1 has been implicated in oncogenic roles in multiple cancers, including breast cancer and prostate cancer. Previous investigations from our laboratory have established the high expression of SRC-1 in human HCC specimens, where it accelerates HCC progression by enhancing Wnt/beta-catenin signalling. In this study, we uncover a previously unknown role of SRC-1 in HCC metastasis. Our findings reveal that SRC-1 promotes HCC metastasis through the augmentation of MMP-9 expression. The knockdown of SRC-1 effectively mitigated HCC cell metastasis both in vitro and in vivo by suppressing MMP-9 expression. Furthermore, we observed a positive correlation between SRC-1 mRNA levels and MMP-9 mRNA levels in limited and larger cohorts of HCC specimens from GEO database. Mechanistically, SRC-1 operates as a coactivator for NF-κB and AP-1, enhancing MMP-9 promoter activity in HCC cells. Higher levels of SRC-1 and MMP-9 expression are associated with worse overall survival in HCC patients. Treatment with Bufalin, known to inhibit SRC-1 expression, significantly decreased MMP-9 expression and inhibited HCC metastasis in both in vitro and in vivo settings. Our results demonstrated the pivotal role of SRC-1 as a critical modulator in HCC metastasis, presenting a potential therapeutic target for HCC intervention.
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Affiliation(s)
- Zhangwei Tong
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
- Department of Molecular and Cellular BiologyBaylor College of MedicineHoustonTexasUSA
| | - Yong Zhang
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
| | - Peng Guo
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
| | - Wei Wang
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
| | - Qiang Chen
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
| | - Jing Jin
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
| | - Shixiao Liu
- Department of Cardiology, School of MedicineThe First Affiliated Hospital of Xiamen University, Xiamen UniversityXiamenChina
| | - Chundong Yu
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
| | - Pingli Mo
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life SciencesXiamen UniversityXiamenChina
| | - Lei Zhang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Department of Hepatobiliary Surgery, Shanxi Bethune Hospital, Shanxi Academy of Medical SciencesShanxi Medical University; Shanxi Tongji Hospital, Huazhong University of Science and TechnologyTaiyuanChina
| | - Junli Huang
- Department of General SurgeryArmy 73rd Group Military Hospital of the Chinese People's Liberation Army (Chenggong Hospital of Xiamen University)XiamenChina
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39
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Lebreton J, Colin L, Chatre E, Bernard P. RNAP II antagonizes mitotic chromatin folding and chromosome segregation by condensin. Cell Rep 2024; 43:113901. [PMID: 38446663 DOI: 10.1016/j.celrep.2024.113901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 12/07/2023] [Accepted: 02/16/2024] [Indexed: 03/08/2024] Open
Abstract
Condensin shapes mitotic chromosomes by folding chromatin into loops, but whether it does so by DNA-loop extrusion remains speculative. Although loop-extruding cohesin is stalled by transcription, the impact of transcription on condensin, which is enriched at highly expressed genes in many species, remains unclear. Using degrons of Rpb1 or the torpedo nuclease Dhp1XRN2 to either deplete or displace RNAPII on chromatin in fission yeast metaphase cells, we show that RNAPII does not load condensin on DNA. Instead, RNAPII retains condensin in cis and hinders its ability to fold mitotic chromatin and to support chromosome segregation, consistent with the stalling of a loop extruder. Transcription termination by Dhp1 limits such a hindrance. Our results shed light on the integrated functioning of condensin, and we argue that a tight control of transcription underlies mitotic chromosome assembly by loop-extruding condensin.
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Affiliation(s)
- Jérémy Lebreton
- ENS de Lyon, University Lyon, 46 allée d'Italie, 69007 Lyon, France
| | - Léonard Colin
- CNRS Laboratory of Biology and Modelling of the Cell, UMR 5239, ENS de Lyon, 46 allée d'Italie, 69007 Lyon, France
| | - Elodie Chatre
- Lymic-Platim, University Lyon, Université Claude Bernard Lyon 1, ENS de Lyon, CNRS UAR3444, Inserm US8, SFR Biosciences, 50 Avenue Tony Garnier, 69007 Lyon, France
| | - Pascal Bernard
- ENS de Lyon, University Lyon, 46 allée d'Italie, 69007 Lyon, France; CNRS Laboratory of Biology and Modelling of the Cell, UMR 5239, ENS de Lyon, 46 allée d'Italie, 69007 Lyon, France.
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40
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Bastié N, Chapard C, Cournac A, Nejmi S, Mboumba H, Gadal O, Thierry A, Beckouët F, Koszul R. Sister chromatid cohesion halts DNA loop expansion. Mol Cell 2024; 84:1139-1148.e5. [PMID: 38452765 DOI: 10.1016/j.molcel.2024.02.004] [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: 07/26/2023] [Revised: 12/02/2023] [Accepted: 02/06/2024] [Indexed: 03/09/2024]
Abstract
Eukaryotic genomes are folded into DNA loops mediated by structural maintenance of chromosomes (SMC) complexes such as cohesin, condensin, and Smc5/6. This organization regulates different DNA-related processes along the cell cycle, such as transcription, recombination, segregation, and DNA repair. During the G2 stage, SMC-mediated DNA loops coexist with cohesin complexes involved in sister chromatid cohesion (SCC). However, the articulation between the establishment of SCC and the formation of SMC-mediated DNA loops along the chromatin remains unknown. Here, we show that SCC is indeed a barrier to cohesin-mediated DNA loop expansion along G2/M Saccharomyces cerevisiae chromosomes.
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Affiliation(s)
- Nathalie Bastié
- Molecular, Cellular, and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Christophe Chapard
- Institut Pasteur, CNRS UMR 3525, Université Paris Cité, Unité Régulation Spatiale des Génomes, 75015 Paris, France
| | - Axel Cournac
- Institut Pasteur, CNRS UMR 3525, Université Paris Cité, Unité Régulation Spatiale des Génomes, 75015 Paris, France
| | - Sanae Nejmi
- Cancer Research Centre of Toulouse, INSERM UMR 1037, 31037 Toulouse, France
| | - Henri Mboumba
- Molecular, Cellular, and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Olivier Gadal
- Molecular, Cellular, and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Agnès Thierry
- Institut Pasteur, CNRS UMR 3525, Université Paris Cité, Unité Régulation Spatiale des Génomes, 75015 Paris, France
| | - Frederic Beckouët
- Molecular, Cellular, and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France.
| | - Romain Koszul
- Institut Pasteur, CNRS UMR 3525, Université Paris Cité, Unité Régulation Spatiale des Génomes, 75015 Paris, France.
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41
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Roy S, Adhikary H, D’Amours D. The SMC5/6 complex: folding chromosomes back into shape when genomes take a break. Nucleic Acids Res 2024; 52:2112-2129. [PMID: 38375830 PMCID: PMC10954462 DOI: 10.1093/nar/gkae103] [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: 11/13/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/21/2024] Open
Abstract
High-level folding of chromatin is a key determinant of the shape and functional state of chromosomes. During cell division, structural maintenance of chromosome (SMC) complexes such as condensin and cohesin ensure large-scale folding of chromatin into visible chromosomes. In contrast, the SMC5/6 complex plays more local and context-specific roles in the structural organization of interphase chromosomes with important implications for health and disease. Recent advances in single-molecule biophysics and cryo-electron microscopy revealed key insights into the architecture of the SMC5/6 complex and how interactions connecting the complex to chromatin components give rise to its unique repertoire of interphase functions. In this review, we provide an integrative view of the features that differentiates the SMC5/6 complex from other SMC enzymes and how these enable dramatic reorganization of DNA folding in space during DNA repair reactions and other genome transactions. Finally, we explore the mechanistic basis for the dynamic targeting of the SMC5/6 complex to damaged chromatin and its crucial role in human health.
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Affiliation(s)
- Shamayita Roy
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Hemanta Adhikary
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Damien D’Amours
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
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42
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Roisné-Hamelin F, Liu HW, Taschner M, Li Y, Gruber S. Structural basis for plasmid restriction by SMC JET nuclease. Mol Cell 2024; 84:883-896.e7. [PMID: 38309275 DOI: 10.1016/j.molcel.2024.01.009] [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: 10/03/2023] [Revised: 12/06/2023] [Accepted: 01/09/2024] [Indexed: 02/05/2024]
Abstract
DNA loop-extruding SMC complexes play crucial roles in chromosome folding and DNA immunity. Prokaryotic SMC Wadjet (JET) complexes limit the spread of plasmids through DNA cleavage, yet the mechanisms for plasmid recognition are unresolved. We show that artificial DNA circularization renders linear DNA susceptible to JET nuclease cleavage. Unlike free DNA, JET cleaves immobilized plasmid DNA at a specific site, the plasmid-anchoring point, showing that the anchor hinders DNA extrusion but not DNA cleavage. Structures of plasmid-bound JetABC reveal two presumably stalled SMC motor units that are drastically rearranged from the resting state, together entrapping a U-shaped DNA segment, which is further converted to kinked V-shaped cleavage substrate by JetD nuclease binding. Our findings uncover mechanical bending of residual unextruded DNA as molecular signature for plasmid recognition and non-self DNA elimination. We moreover elucidate key elements of SMC loop extrusion, including the motor direction and the structure of a DNA-holding state.
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Affiliation(s)
- Florian Roisné-Hamelin
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), 1015 Lausanne, Switzerland
| | - Hon Wing Liu
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), 1015 Lausanne, Switzerland
| | - Michael Taschner
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), 1015 Lausanne, Switzerland
| | - Yan Li
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), 1015 Lausanne, Switzerland
| | - Stephan Gruber
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), 1015 Lausanne, Switzerland.
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43
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Beilinson HA, Erickson SA, Golovkina T. The endogenous Mtv8 locus and the immunoglobulin repertoire. Front Immunol 2024; 15:1345467. [PMID: 38504980 PMCID: PMC10948529 DOI: 10.3389/fimmu.2024.1345467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 02/16/2024] [Indexed: 03/21/2024] Open
Abstract
The vast diversity of mammalian adaptive antigen receptors allows for robust and efficient immune responses against a wide number of pathogens. The antigen receptor repertoire is built during the recombination of B and T cell receptor (BCR, TCR) loci and hypermutation of BCR loci. V(D)J recombination rearranges these antigen receptor loci, which are organized as an array of separate V, (D), and J gene segments. Transcription activation at the recombining locus leads to changes in the local three-dimensional architecture, which subsequently contributes to which gene segments are utilized for recombination. The endogenous retrovirus (ERV) mouse mammary tumor provirus 8 (Mtv8) resides on mouse chromosome 6 interposed within the large array of light chain kappa V gene segments. As ERVs contribute to changes in genomic architecture by driving high levels of transcription of neighboring genes, it was suggested that Mtv8 could influence the BCR repertoire. We generated Mtv8-deficient mice to determine if the ERV influences V(D)J recombination to test this possibility. We find that Mtv8 does not influence the BCR repertoire.
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Affiliation(s)
- Helen A Beilinson
- Department of Microbiology, University of Chicago, Chicago, IL, United States
| | - Steven A Erickson
- Department of Immunobiology, Yale University, New Haven, CT, United States
| | - Tatyana Golovkina
- Department of Microbiology, University of Chicago, Chicago, IL, United States
- Committee on Microbiology, University of Chicago, Chicago, IL, United States
- Committee on Immunology, University of Chicago, Chicago, IL, United States
- Committee on Genetics, Genomics and System Biology, University of Chicago, Chicago, IL, United States
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44
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Li X, Zeng S, Chen L, Zhang Y, Li X, Zhang B, Su D, Du Q, Zhang J, Wang H, Zhong Z, Zhang J, Li P, Jiang A, Long K, Li M, Ge L. An intronic enhancer of Cebpa regulates adipocyte differentiation and adipose tissue development via long-range loop formation. Cell Prolif 2024; 57:e13552. [PMID: 37905345 PMCID: PMC10905358 DOI: 10.1111/cpr.13552] [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: 04/24/2023] [Revised: 08/29/2023] [Accepted: 09/11/2023] [Indexed: 11/02/2023] Open
Abstract
Cebpa is a master transcription factor gene for adipogenesis. However, the mechanisms of enhancer-promoter chromatin interactions controlling Cebpa transcriptional regulation during adipogenic differentiation remain largely unknown. To reveal how the three-dimensional structure of Cebpa changes during adipogenesis, we generated high-resolution chromatin interactions of Cebpa in 3T3-L1 preadipocytes and 3T3-L1 adipocytes using circularized chromosome conformation capture sequencing (4C-seq). We revealed dramatic changes in chromatin interactions and chromatin status at interaction sites during adipogenic differentiation. Based on this, we identified five active enhancers of Cebpa in 3T3-L1 adipocytes through epigenomic data and luciferase reporter assays. Next, epigenetic repression of Cebpa-L1-AD-En2 or -En3 by the dCas9-KRAB system significantly down-regulated Cebpa expression and inhibited adipocyte differentiation. Furthermore, experimental depletion of cohesin decreased the interaction intensity between Cebpa-L1-AD-En2 and the Cebpa promoter and down-regulated Cebpa expression, indicating that long-range chromatin loop formation was mediated by cohesin. Two transcription factors, RXRA and PPARG, synergistically regulate the activity of Cebpa-L1-AD-En2. To test whether Cebpa-L1-AD-En2 plays a role in adipose tissue development, we injected dCas9-KRAB-En2 lentivirus into the inguinal white adipose tissue (iWAT) of mice to suppress the activity of Cebpa-L1-AD-En2. Repression of Cebpa-L1-AD-En2 significantly decreased Cebpa expression and adipocyte size, altered iWAT transcriptome, and affected iWAT development. We identified functional enhancers regulating Cebpa expression and clarified the crucial roles of Cebpa-L1-AD-En2 and Cebpa promoter interaction in adipocyte differentiation and adipose tissue development.
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Affiliation(s)
- Xiaokai Li
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Sha Zeng
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Li Chen
- Chongqing Academy of Animal SciencesChongqingChina
- National Center of Technology Innovation for PigsChongqingChina
- Key Laboratory of Pig Industry ScienceMinistry of AgricultureChongqingChina
| | - Yu Zhang
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Xuemin Li
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Biwei Zhang
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Duo Su
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Qinjiao Du
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Jiaman Zhang
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Haoming Wang
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Zhining Zhong
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Jinwei Zhang
- Chongqing Academy of Animal SciencesChongqingChina
- National Center of Technology Innovation for PigsChongqingChina
- Key Laboratory of Pig Industry ScienceMinistry of AgricultureChongqingChina
| | - Penghao Li
- Jinxin Research Institute for Reproductive Medicine and GeneticsSichuan Jinxin Xi'nan Women's and Children's HospitalChengduChina
| | - Anan Jiang
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Keren Long
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
- Chongqing Academy of Animal SciencesChongqingChina
| | - Mingzhou Li
- State Key Laboratory of Swine and Poultry Breeding IndustrySichuan Agricultural UniversityChengduChina
- Livestock and Poultry Multi‐omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and TechnologySichuan Agricultural UniversityChengduChina
| | - Liangpeng Ge
- Chongqing Academy of Animal SciencesChongqingChina
- National Center of Technology Innovation for PigsChongqingChina
- Key Laboratory of Pig Industry ScienceMinistry of AgricultureChongqingChina
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45
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Abugable AA, Antar S, El-Khamisy SF. Chromosomal single-strand break repair and neurological disease: Implications on transcription and emerging genomic tools. DNA Repair (Amst) 2024; 135:103629. [PMID: 38266593 DOI: 10.1016/j.dnarep.2024.103629] [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: 10/14/2023] [Revised: 12/21/2023] [Accepted: 01/04/2024] [Indexed: 01/26/2024]
Abstract
Cells are constantly exposed to various sources of DNA damage that pose a threat to their genomic integrity. One of the most common types of DNA breaks are single-strand breaks (SSBs). Mutations in the repair proteins that are important for repairing SSBs have been reported in several neurological disorders. While several tools have been utilised to investigate SSBs in cells, it was only through recent advances in genomics that we are now beginning to understand the architecture of the non-random distribution of SSBs and their impact on key cellular processes such as transcription and epigenetic remodelling. Here, we discuss our current understanding of the genome-wide distribution of SSBs, their link to neurological disorders and summarise recent technologies to investigate SSBs at the genomic level.
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Affiliation(s)
- Arwa A Abugable
- School of Biosciences, Firth Court, University of Sheffield, Sheffield, UK; The healthy Lifespan and Neuroscience Institutes, University of Sheffield, Sheffield, UK
| | - Sarah Antar
- School of Biosciences, Firth Court, University of Sheffield, Sheffield, UK; The healthy Lifespan and Neuroscience Institutes, University of Sheffield, Sheffield, UK; Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Mansoura University, Egypt
| | - Sherif F El-Khamisy
- School of Biosciences, Firth Court, University of Sheffield, Sheffield, UK; The healthy Lifespan and Neuroscience Institutes, University of Sheffield, Sheffield, UK; Institute of Cancer Therapeutics, Faculty of Life Sciences, University of Bradford, Bradford, UK.
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46
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Yaguchi H, Melamed A, Ramanayake S, Kiik H, Witkover A, Bangham CRM. The impact of HTLV-1 expression on the 3D structure and expression of host chromatin. PLoS Pathog 2024; 20:e1011716. [PMID: 38427693 PMCID: PMC10936777 DOI: 10.1371/journal.ppat.1011716] [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: 09/29/2023] [Revised: 03/13/2024] [Accepted: 02/12/2024] [Indexed: 03/03/2024] Open
Abstract
A typical HTLV-1-infected individual carries >104 different HTLV-1-infected T cell clones, each with a single-copy provirus integrated in a unique genomic site. We previously showed that the HTLV-1 provirus causes aberrant transcription in the flanking host genome and, by binding the chromatin architectural protein CTCF, forms abnormal chromatin loops with the host genome. However, it remained unknown whether these effects were exerted simply by the presence of the provirus or were induced by its transcription. To answer this question, we sorted HTLV-1-infected T-cell clones into cells positive or negative for proviral plus-strand expression, and then quantified host and provirus transcription using RNA-seq, and chromatin looping using quantitative chromosome conformation capture (q4C), in each cell population. We found that proviral plus-strand transcription induces aberrant transcription and splicing in the flanking genome but suppresses aberrant chromatin loop formation with the nearby host chromatin. Reducing provirus-induced host transcription with an inhibitor of transcriptional elongation allows recovery of chromatin loops in the plus-strand-expressing population. We conclude that aberrant host transcription induced by proviral expression causes temporary, reversible disruption of chromatin looping in the vicinity of the provirus.
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Affiliation(s)
- Hiroko Yaguchi
- Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Anat Melamed
- Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Saumya Ramanayake
- Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Helen Kiik
- Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Aviva Witkover
- Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Charles R. M. Bangham
- Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, United Kingdom
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47
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Segev A, Heady L, Crewe M, Madabhushi R. Mapping catalytically engaged TOP2B in neurons reveals the principles of topoisomerase action within the genome. Cell Rep 2024; 43:113809. [PMID: 38377005 PMCID: PMC11064056 DOI: 10.1016/j.celrep.2024.113809] [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: 03/20/2023] [Revised: 12/22/2023] [Accepted: 01/31/2024] [Indexed: 02/22/2024] Open
Abstract
We trapped catalytically engaged topoisomerase IIβ (TOP2B) in covalent DNA cleavage complexes (TOP2Bccs) and mapped their positions genome-wide in cultured mouse cortical neurons. We report that TOP2Bcc distribution varies with both nucleosome and compartmental chromosome organization. While TOP2Bccs in gene bodies correlate with their level of transcription, highly expressed genes that lack the usually associated chromatin marks, such as H3K36me3, show reduced TOP2Bccs, suggesting that histone posttranslational modifications regulate TOP2B activity. Promoters with high RNA polymerase II occupancy show elevated TOP2B chromatin immunoprecipitation sequencing signals but low TOP2Bccs, indicating that TOP2B catalytic engagement is curtailed at active promoters. Surprisingly, either poisoning or inhibiting TOP2B increases nascent transcription at most genes and enhancers but reduces transcription within long genes. These effects are independent of transcript length and instead correlate with the presence of intragenic enhancers. Together, these results clarify how cells modulate the catalytic engagement of topoisomerases to affect transcription.
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Affiliation(s)
- Amir Segev
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lance Heady
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Morgan Crewe
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ram Madabhushi
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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48
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Iida S, Ide S, Tamura S, Tani T, Goto T, Shribak M, Maeshima K. Orientation-Independent-DIC imaging reveals that a transient rise in depletion force contributes to mitotic chromosome condensation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.11.566679. [PMID: 37986866 PMCID: PMC10659371 DOI: 10.1101/2023.11.11.566679] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Genomic information must be faithfully transmitted into two daughter cells during mitosis. To ensure the transmission process, interphase chromatin is further condensed into mitotic chromosomes. Although protein factors like condensins and topoisomerase IIα are involved in the assembly of mitotic chromosomes, the physical bases of the condensation process remain unclear. Depletion force/macromolecular crowding, an effective attractive force that arises between large structures in crowded environments around chromosomes, may contribute to the condensation process. To approach this issue, we investigated the "chromosome milieu" during mitosis of living human cells using orientation-independent-differential interference contrast (OI-DIC) module combined with a confocal laser scanning microscope, which is capable of precisely mapping optical path differences and estimating molecular densities. We found that the molecular density surrounding chromosomes increased with the progression from prometaphase to anaphase, concurring with chromosome condensation. However, the molecular density went down in telophase, when chromosome decondensation began. Changes in the molecular density around chromosomes by hypotonic or hypertonic treatment consistently altered the condensation levels of chromosomes. In vitro, native chromatin was converted into liquid droplets of chromatin in the presence of cations and a macromolecular crowder. Additional crowder made the chromatin droplets stiffer and more solid-like, with further condensation. These results suggest that a transient rise in depletion force, likely triggered by the relocation of macromolecules (proteins, RNAs and others) via nuclear envelope breakdown and also by a subsequent decrease in cell-volumes, contributes to mitotic chromosome condensation, shedding light on a new aspect of the condensation mechanism in living human cells.
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Affiliation(s)
- Shiori Iida
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Satoru Ide
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Sachiko Tamura
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Tomomi Tani
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
| | - Tatsuhiko Goto
- Research Center for Global Agromedicine and Department of Life and Food Sciences, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
| | - Michael Shribak
- Marine Biological Laboratory, 7 MBL St, Woods Hole, MA 02543, USA
| | - Kazuhiro Maeshima
- Genome Dynamics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
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49
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Hung TC, Kingsley DM, Boettiger AN. Boundary stacking interactions enable cross-TAD enhancer-promoter communication during limb development. Nat Genet 2024; 56:306-314. [PMID: 38238628 DOI: 10.1038/s41588-023-01641-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 12/06/2023] [Indexed: 02/15/2024]
Abstract
Although promoters and their enhancers are frequently contained within a topologically associating domain (TAD), some developmentally important genes have their promoter and enhancers within different TADs. Hypotheses about molecular mechanisms enabling cross-TAD interactions remain to be assessed. To test these hypotheses, we used optical reconstruction of chromatin architecture to characterize the conformations of the Pitx1 locus on single chromosomes in developing mouse limbs. Our data support a model in which neighboring boundaries are stacked as a result of loop extrusion, bringing boundary-proximal cis-elements into contact. This stacking interaction also contributes to the appearance of architectural stripes in the population average maps. Through molecular dynamics simulations, we found that increasing boundary strengths facilitates the formation of the stacked boundary conformation, counter-intuitively facilitating border bypass. This work provides a revised view of the TAD borders' function, both facilitating and preventing cis-regulatory interactions, and introduces a framework to distinguish border-crossing from border-respecting enhancer-promoter pairs.
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Affiliation(s)
- Tzu-Chiao Hung
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - David M Kingsley
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Alistair N Boettiger
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA.
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50
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Miglierina E, Ordanoska D, Le Noir S, Laffleur B. RNA processing mechanisms contribute to genome organization and stability in B cells. Oncogene 2024; 43:615-623. [PMID: 38287115 PMCID: PMC10890934 DOI: 10.1038/s41388-024-02952-2] [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: 08/29/2023] [Revised: 01/15/2024] [Accepted: 01/18/2024] [Indexed: 01/31/2024]
Abstract
RNA processing includes post-transcriptional mechanisms controlling RNA quality and quantity to ensure cellular homeostasis. Noncoding (nc) RNAs that are regulated by these dynamic processes may themselves fulfill effector and/or regulatory functions, and recent studies demonstrated the critical role of RNAs in organizing both chromatin and genome architectures. Furthermore, RNAs can threaten genome integrity when accumulating as DNA:RNA hybrids, but could also facilitate DNA repair depending on the molecular context. Therefore, by qualitatively and quantitatively fine-tuning RNAs, RNA processing contributes directly or indirectly to chromatin states, genome organization, and genome stability. B lymphocytes represent a unique model to study these interconnected mechanisms as they express ncRNAs transcribed from key specific sequences before undergoing physiological genetic remodeling processes, including V(D)J recombination, somatic hypermutation, and class switch recombination. RNA processing actors ensure the regulation and degradation of these ncRNAs for efficient DNA repair and immunoglobulin gene remodeling while failure leads to B cell development alterations, aberrant DNA repair, and pathological translocations. This review highlights how RNA processing mechanisms contribute to genome architecture and stability, with emphasis on their critical roles during B cell development, enabling physiological DNA remodeling while preventing lymphomagenesis.
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Affiliation(s)
- Emma Miglierina
- University of Rennes, Inserm, EFS Bretagne, CHU Rennes, UMR, 1236, Rennes, France
| | - Delfina Ordanoska
- University of Rennes, Inserm, EFS Bretagne, CHU Rennes, UMR, 1236, Rennes, France
| | - Sandrine Le Noir
- UMR CNRS 7276, Inserm 1262, Université de Limoges: Contrôle de la Réponse Immune B et des Lymphoproliférations, Team 2, B-NATION: B cell Nuclear Architecture, Immunoglobulin genes and Oncogenes, Limoges, France
| | - Brice Laffleur
- University of Rennes, Inserm, EFS Bretagne, CHU Rennes, UMR, 1236, Rennes, France.
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