1
|
Rubio LS, Mohajan S, Gross DS. Heat Shock Factor 1 forms nuclear condensates and restructures the yeast genome before activating target genes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.28.560064. [PMID: 37808805 PMCID: PMC10557744 DOI: 10.1101/2023.09.28.560064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
In insects and mammals, 3D genome topology has been linked to transcriptional states yet whether this link holds for other eukaryotes is unclear. Using both ligation proximity and fluorescence microscopy assays, we show that in Saccharomyces cerevisiae, Heat Shock Response (HSR) genes dispersed across multiple chromosomes and under the control of Heat Shock Factor (Hsf1) rapidly reposition in cells exposed to acute ethanol stress and engage in concerted, Hsf1-dependent intergenic interactions. Accompanying 3D genome reconfiguration is equally rapid formation of Hsf1-containing condensates. However, in contrast to the transience of Hsf1-driven intergenic interactions that peak within 10-20 min and dissipate within 1 h in the presence of 8.5% (v/v) ethanol, transcriptional condensates are stably maintained for hours. Moreover, under the same conditions, Pol II occupancy of HSR genes, chromatin remodeling, and RNA expression are detectable only later in the response and peak much later (>1 h). This contrasts with the coordinate response of HSR genes to thermal stress (39°C) where Pol II occupancy, transcription, histone eviction, intergenic interactions, and formation of Hsf1 condensates are all rapid yet transient (peak within 2.5-10 min and dissipate within 1 h). Therefore, Hsf1 forms condensates, restructures the genome and transcriptionally activates HSR genes in response to both forms of proteotoxic stress but does so with strikingly different kinetics. In cells subjected to ethanol stress, Hsf1 forms condensates and repositions target genes before transcriptionally activating them.
Collapse
Affiliation(s)
- Linda S. Rubio
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130
| | - Suman Mohajan
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130
| | - David S. Gross
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130
| |
Collapse
|
2
|
Hyder U, Challa A, Thornton M, Nandu T, Kraus WL, D'Orso I. KAP1 negatively regulates RNA polymerase II elongation kinetics to activate signal-induced transcription. Nat Commun 2024; 15:5859. [PMID: 38997286 PMCID: PMC11245487 DOI: 10.1038/s41467-024-49905-7] [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: 11/05/2023] [Accepted: 06/20/2024] [Indexed: 07/14/2024] Open
Abstract
Signal-induced transcriptional programs regulate critical biological processes through the precise spatiotemporal activation of Immediate Early Genes (IEGs); however, the mechanisms of transcription induction remain poorly understood. By combining an acute depletion system with several genomics approaches to interrogate synchronized, temporal transcription, we reveal that KAP1/TRIM28 is a first responder that fulfills the temporal and heightened transcriptional demand of IEGs. Acute KAP1 loss triggers an increase in RNA polymerase II elongation kinetics during early stimulation time points. This elongation defect derails the normal progression through the transcriptional cycle during late stimulation time points, ultimately leading to decreased recruitment of the transcription apparatus for re-initiation thereby dampening IEGs transcriptional output. Collectively, KAP1 plays a counterintuitive role by negatively regulating transcription elongation to support full activation across multiple transcription cycles of genes critical for cell physiology and organismal functions.
Collapse
Affiliation(s)
- Usman Hyder
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Ashwini Challa
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Micah Thornton
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Tulip Nandu
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - W Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Iván D'Orso
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
| |
Collapse
|
3
|
Puerto M, Shukla M, Bujosa P, Pérez-Roldán J, Torràs-Llort M, Tamirisa S, Carbonell A, Solé C, Puspo J, Cummings C, de Nadal E, Posas F, Azorín F, Rowley M. The zinc-finger protein Z4 cooperates with condensin II to regulate somatic chromosome pairing and 3D chromatin organization. Nucleic Acids Res 2024; 52:5596-5609. [PMID: 38520405 PMCID: PMC11162801 DOI: 10.1093/nar/gkae198] [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: 10/24/2023] [Revised: 02/16/2024] [Accepted: 03/07/2024] [Indexed: 03/25/2024] Open
Abstract
Chromosome pairing constitutes an important level of genome organization, yet the mechanisms that regulate pairing in somatic cells and the impact on 3D chromatin organization are still poorly understood. Here, we address these questions in Drosophila, an organism with robust somatic pairing. In Drosophila, pairing preferentially occurs at loci consisting of numerous architectural protein binding sites (APBSs), suggesting a role of architectural proteins (APs) in pairing regulation. Amongst these, the anti-pairing function of the condensin II subunit CAP-H2 is well established. However, the factors that regulate CAP-H2 localization and action at APBSs remain largely unknown. Here, we identify two factors that control CAP-H2 occupancy at APBSs and, therefore, regulate pairing. We show that Z4, interacts with CAP-H2 and is required for its localization at APBSs. We also show that hyperosmotic cellular stress induces fast and reversible unpairing in a Z4/CAP-H2 dependent manner. Moreover, by combining the opposite effects of Z4 depletion and osmostress, we show that pairing correlates with the strength of intrachromosomal 3D interactions, such as active (A) compartment interactions, intragenic gene-loops, and polycomb (Pc)-mediated chromatin loops. Altogether, our results reveal new players in CAP-H2-mediated pairing regulation and the intimate interplay between inter-chromosomal and intra-chromosomal 3D interactions.
Collapse
Affiliation(s)
- Marta Puerto
- Institute of Molecular Biology of Barcelona, IBMB, CSIC, Baldiri Reixac 4, 08028 Barcelona, Spain
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Mamta Shukla
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, USA
| | - Paula Bujosa
- Institute of Molecular Biology of Barcelona, IBMB, CSIC, Baldiri Reixac 4, 08028 Barcelona, Spain
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Juan Pérez-Roldán
- Institute of Molecular Biology of Barcelona, IBMB, CSIC, Baldiri Reixac 4, 08028 Barcelona, Spain
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Mònica Torràs-Llort
- Institute of Molecular Biology of Barcelona, IBMB, CSIC, Baldiri Reixac 4, 08028 Barcelona, Spain
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Srividya Tamirisa
- Institute of Molecular Biology of Barcelona, IBMB, CSIC, Baldiri Reixac 4, 08028 Barcelona, Spain
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Albert Carbonell
- Institute of Molecular Biology of Barcelona, IBMB, CSIC, Baldiri Reixac 4, 08028 Barcelona, Spain
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Carme Solé
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
- Department of Medicine and Life Sciences (MELIS), Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Joynob Akter Puspo
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, USA
| | | | - Eulàlia de Nadal
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
- Department of Medicine and Life Sciences (MELIS), Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Francesc Posas
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
- Department of Medicine and Life Sciences (MELIS), Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Fernando Azorín
- Institute of Molecular Biology of Barcelona, IBMB, CSIC, Baldiri Reixac 4, 08028 Barcelona, Spain
- Institute for Research in Biomedicine of Barcelona, IRB Barcelona. The Barcelona Institute of Science and Technology. Baldiri Reixac 10, 08028 Barcelona, Spain
| | - M Jordan Rowley
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, USA
| |
Collapse
|
4
|
Hyder U, Challa A, Thornton M, Nandu T, Kraus WL, D’Orso I. KAP1 negatively regulates RNA polymerase II elongation kinetics to activate signal-induced transcription. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.05.592422. [PMID: 38746145 PMCID: PMC11092767 DOI: 10.1101/2024.05.05.592422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Signal-induced transcriptional programs regulate critical biological processes through the precise spatiotemporal activation of Immediate Early Genes (IEGs); however, the mechanisms of transcription induction remain poorly understood. By combining an acute depletion system with high resolution genomics approaches to interrogate synchronized, temporal transcription, we reveal that KAP1/TRIM28 is a first responder that fulfills the temporal and heightened transcriptional demand of IEGs. Unexpectedly, acute KAP1 loss triggers an increase in RNA polymerase II elongation kinetics during early stimulation time points. This elongation defect derails the normal progression through the transcriptional cycle during late stimulation time points, ultimately leading to decreased recruitment of the transcription apparatus for re-initiation thereby dampening IEGs transcriptional output. Collectively, KAP1 plays a counterintuitive role by negatively regulating transcription elongation to support full activation across multiple transcription cycles of genes critical for cell physiology and organismal functions.
Collapse
Affiliation(s)
- Usman Hyder
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ashwini Challa
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Micah Thornton
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tulip Nandu
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - W. Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Iván D’Orso
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| |
Collapse
|
5
|
Kindongo O, Lieb G, Skaggs B, Dusserre Y, Vincenzetti V, Pelet S. Implication of polymerase recycling for nascent transcript quantification by live cell imaging. Yeast 2024; 41:279-294. [PMID: 38389243 DOI: 10.1002/yea.3929] [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: 09/25/2023] [Revised: 12/29/2023] [Accepted: 01/18/2024] [Indexed: 02/24/2024] Open
Abstract
Transcription enables the production of RNA from a DNA template. Due to the highly dynamic nature of transcription, live-cell imaging methods play a crucial role in measuring the kinetics of this process. For instance, transcriptional bursts have been visualized using fluorescent phage-coat proteins that associate tightly with messenger RNA (mRNA) stem loops formed on nascent transcripts. To convert the signal emanating from a transcription site into meaningful estimates of transcription dynamics, the influence of various parameters on the measured signal must be evaluated. Here, the effect of gene length on the intensity of the transcription site focus was analyzed. Intuitively, a longer gene can support a larger number of transcribing polymerases, thus leading to an increase in the measured signal. However, measurements of transcription induced by hyper-osmotic stress responsive promoters display independence from gene length. A mathematical model of the stress-induced transcription process suggests that the formation of gene loops that favor the recycling of polymerase from the terminator to the promoter can explain the observed behavior. One experimentally validated prediction from this model is that the amount of mRNA produced from a short gene should be higher than for a long one as the density of active polymerase on the short gene will be increased by polymerase recycling. Our data suggest that this recycling contributes significantly to the expression output from a gene and that polymerase recycling is modulated by the promoter identity and the cellular state.
Collapse
Affiliation(s)
- Olivia Kindongo
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Guillaume Lieb
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Benjamin Skaggs
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Yves Dusserre
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Vincent Vincenzetti
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Serge Pelet
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
6
|
Alfonso-Gonzalez C, Hilgers V. (Alternative) transcription start sites as regulators of RNA processing. Trends Cell Biol 2024:S0962-8924(24)00033-3. [PMID: 38531762 DOI: 10.1016/j.tcb.2024.02.010] [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: 12/21/2023] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 03/28/2024]
Abstract
Alternative transcription start site usage (ATSS) is a widespread regulatory strategy that enables genes to choose between multiple genomic loci for initiating transcription. This mechanism is tightly controlled during development and is often altered in disease states. In this review, we examine the growing evidence highlighting a role for transcription start sites (TSSs) in the regulation of mRNA isoform selection during and after transcription. We discuss how the choice of transcription initiation sites influences RNA processing and the importance of this crosstalk for cell identity and organism function. We also speculate on possible mechanisms underlying the integration of transcriptional and post-transcriptional processes.
Collapse
Affiliation(s)
- Carlos Alfonso-Gonzalez
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany; Faculty of Biology, Albert Ludwigs University, 79104 Freiburg, Germany; International Max Planck Research School for Molecular and Cellular Biology (IMPRS- MCB), 79108 Freiburg, Germany
| | - Valérie Hilgers
- Max Planck Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany.
| |
Collapse
|
7
|
Fidler E, Dwyer K, Ansari A. Ssu72: a versatile protein with functions in transcription and beyond. Front Mol Biosci 2024; 11:1332878. [PMID: 38304578 PMCID: PMC10830811 DOI: 10.3389/fmolb.2024.1332878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 01/08/2024] [Indexed: 02/03/2024] Open
Abstract
Eukaryotic transcription is a complex process involving a vast network of protein and RNA factors that influence gene expression. The main player in transcription is the RNA polymerase that synthesizes the RNA from the DNA template. RNA polymerase II (RNAPII) transcribes all protein coding genes and some noncoding RNAs in eukaryotic cells. The polymerase is aided by interacting partners that shuttle it along the gene for initiation, elongation and termination of transcription. One of the many factors that assist RNAPII in transcription of genes is Ssu72. It is a carboxy-terminal-domain (CTD)-phosphatase that plays pleiotropic roles in the transcription cycle. It is essential for cell viability in Saccharomyces cerevisiae, the organism in which it was discovered. The homologues of Ssu72 have been identified in humans, mice, plants, flies, and fungi thereby suggesting the evolutionarily conserved nature of the protein. Recent studies have implicated the factor beyond the confines of transcription in homeostasis and diseases.
Collapse
Affiliation(s)
| | | | - Athar Ansari
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| |
Collapse
|
8
|
Lee H, Seo P. Accessible gene borders establish a core structural unit for chromatin architecture in Arabidopsis. Nucleic Acids Res 2023; 51:10261-10277. [PMID: 37884483 PMCID: PMC10602878 DOI: 10.1093/nar/gkad710] [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: 03/22/2023] [Revised: 08/08/2023] [Accepted: 08/16/2023] [Indexed: 10/28/2023] Open
Abstract
Three-dimensional (3D) chromatin structure is linked to transcriptional regulation in multicellular eukaryotes including plants. Taking advantage of high-resolution Hi-C (high-throughput chromatin conformation capture), we detected a small structural unit with 3D chromatin architecture in the Arabidopsis genome, which lacks topologically associating domains, and also in the genomes of tomato, maize, and Marchantia polymorpha. The 3D folding domain unit was usually established around an individual gene and was dependent on chromatin accessibility at the transcription start site (TSS) and transcription end site (TES). We also observed larger contact domains containing two or more neighboring genes, which were dependent on accessible border regions. Binding of transcription factors to accessible TSS/TES regions formed these gene domains. We successfully simulated these Hi-C contact maps via computational modeling using chromatin accessibility as input. Our results demonstrate that gene domains establish basic 3D chromatin architecture units that likely contribute to higher-order 3D genome folding in plants.
Collapse
Affiliation(s)
- Hongwoo Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Pil Joon Seo
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul 08826, Korea
| |
Collapse
|
9
|
Patel HP, Coppola S, Pomp W, Aiello U, Brouwer I, Libri D, Lenstra TL. DNA supercoiling restricts the transcriptional bursting of neighboring eukaryotic genes. Mol Cell 2023; 83:1573-1587.e8. [PMID: 37207624 DOI: 10.1016/j.molcel.2023.04.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 02/14/2023] [Accepted: 04/14/2023] [Indexed: 05/21/2023]
Abstract
DNA supercoiling has emerged as a major contributor to gene regulation in bacteria, but how DNA supercoiling impacts transcription dynamics in eukaryotes is unclear. Here, using single-molecule dual-color nascent transcription imaging in budding yeast, we show that transcriptional bursting of divergent and tandem GAL genes is coupled. Temporal coupling of neighboring genes requires rapid release of DNA supercoils by topoisomerases. When DNA supercoils accumulate, transcription of one gene inhibits transcription at its adjacent genes. Transcription inhibition of the GAL genes results from destabilized binding of the transcription factor Gal4. Moreover, wild-type yeast minimizes supercoiling-mediated inhibition by maintaining sufficient levels of topoisomerases. Overall, we discover fundamental differences in transcriptional control by DNA supercoiling between bacteria and yeast and show that rapid supercoiling release in eukaryotes ensures proper gene expression of neighboring genes.
Collapse
Affiliation(s)
- Heta P Patel
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Stefano Coppola
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Wim Pomp
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Umberto Aiello
- Université Paris Cité, CNRS, Institut Jacques Monod, 75013 Paris, France
| | - Ineke Brouwer
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Domenico Libri
- Université Paris Cité, CNRS, Institut Jacques Monod, 75013 Paris, France
| | - Tineke L Lenstra
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands.
| |
Collapse
|
10
|
Puerto M, Shukla M, Bujosa P, Perez-Roldan J, Tamirisa S, Solé C, de Nadal E, Posas F, Azorin F, Rowley MJ. Somatic chromosome pairing has a determinant impact on 3D chromatin organization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.29.534693. [PMID: 37034722 PMCID: PMC10081234 DOI: 10.1101/2023.03.29.534693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
In the nucleus, chromatin is intricately structured into multiple layers of 3D organization important for genome activity. How distinct layers influence each other is not well understood. In particular, the contribution of chromosome pairing to 3D chromatin organization has been largely neglected. Here, we address this question in Drosophila, an organism that shows robust chromosome pairing in interphasic somatic cells. The extent of chromosome pairing depends on the balance between pairing and anti-pairing factors, with the anti-pairing activity of the CAP-H2 condensin II subunit being the best documented. Here, we identify the zinc-finger protein Z4 as a strong anti-pairer that interacts with and mediates the chromatin binding of CAP-H2. We also report that hyperosmotic cellular stress induces fast and reversible chromosome unpairing that depends on Z4/CAP-H2. And, most important, by combining Z4 depletion and osmostress, we show that chromosome pairing reinforces intrachromosomal 3D interactions. On the one hand, pairing facilitates RNAPII occupancy that correlates with enhanced intragenic gene-loop interactions. In addition, acting at a distance, pairing reinforces chromatin-loop interactions mediated by Polycomb (Pc). In contrast, chromosome pairing does not affect which genomic intervals segregate to active (A) and inactive (B) compartments, with only minimal effects on the strength of A-A compartmental interactions. Altogether, our results unveil the intimate interplay between inter-chromosomal and intra-chromosomal 3D interactions, unraveling the interwoven relationship between different layers of chromatin organization and the essential contribution of chromosome pairing.
Collapse
|
11
|
Terrone S, Valat J, Fontrodona N, Giraud G, Claude JB, Combe E, Lapendry A, Polvèche H, Ameur LB, Duvermy A, Modolo L, Bernard P, Mortreux F, Auboeuf D, Bourgeois C. RNA helicase-dependent gene looping impacts messenger RNA processing. Nucleic Acids Res 2022; 50:9226-9246. [PMID: 36039747 PMCID: PMC9458439 DOI: 10.1093/nar/gkac717] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 07/25/2022] [Accepted: 08/25/2022] [Indexed: 12/24/2022] Open
Abstract
DDX5 and DDX17 are DEAD-box RNA helicase paralogs which regulate several aspects of gene expression, especially transcription and splicing, through incompletely understood mechanisms. A transcriptome analysis of DDX5/DDX17-depleted human cells confirmed the large impact of these RNA helicases on splicing and revealed a widespread deregulation of 3' end processing. In silico analyses and experiments in cultured cells showed the binding and functional contribution of the genome organizing factor CTCF to chromatin sites at or near a subset of DDX5/DDX17-dependent exons that are characterized by a high GC content and a high density of RNA Polymerase II. We propose the existence of an RNA helicase-dependent relationship between CTCF and the dynamics of transcription across DNA and/or RNA structured regions, that contributes to the processing of internal and terminal exons. Moreover, local DDX5/DDX17-dependent chromatin loops spatially connect RNA helicase-regulated exons with their cognate promoter, and we provide the first direct evidence that de novo gene looping modifies alternative splicing and polyadenylation. Overall our findings uncover the impact of DDX5/DDX17-dependent chromatin folding on pre-messenger RNA processing.
Collapse
Affiliation(s)
| | | | - Nicolas Fontrodona
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | | | - Jean-Baptiste Claude
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | | | - Audrey Lapendry
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Hélène Polvèche
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France,CECS/AFM, I-STEM, 28 rue Henri Desbruères, F-91100, Corbeil-Essonnes, France
| | - Lamya Ben Ameur
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Arnaud Duvermy
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Laurent Modolo
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Pascal Bernard
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Franck Mortreux
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Didier Auboeuf
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Cyril F Bourgeois
- To whom correspondence should be addressed. Tel: +33 47272 8663; Fax: +33 47272 8674;
| |
Collapse
|
12
|
Chou SP, Alexander AK, Rice EJ, Choate LA, Danko CG. Genetic dissection of the RNA polymerase II transcription cycle. eLife 2022; 11:e78458. [PMID: 35775732 PMCID: PMC9286732 DOI: 10.7554/elife.78458] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/30/2022] [Indexed: 11/20/2022] Open
Abstract
How DNA sequence affects the dynamics and position of RNA Polymerase II (Pol II) during transcription remains poorly understood. Here, we used naturally occurring genetic variation in F1 hybrid mice to explore how DNA sequence differences affect the genome-wide distribution of Pol II. We measured the position and orientation of Pol II in eight organs collected from heterozygous F1 hybrid mice using ChRO-seq. Our data revealed a strong genetic basis for the precise coordinates of transcription initiation and promoter proximal pause, allowing us to redefine molecular models of core transcriptional processes. Our results implicate DNA sequence, including both known and novel DNA sequence motifs, as key determinants of the position of Pol II initiation and pause. We report evidence that initiation site selection follows a stochastic process similar to Brownian motion along the DNA template. We found widespread differences in the position of transcription termination, which impact the primary structure and stability of mature mRNA. Finally, we report evidence that allelic changes in transcription often affect mRNA and ncRNA expression across broad genomic domains. Collectively, we reveal how DNA sequences shape core transcriptional processes at single nucleotide resolution in mammals.
Collapse
Affiliation(s)
- Shao-Pei Chou
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| | - Adriana K Alexander
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| | - Edward J Rice
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| | - Lauren A Choate
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| | - Charles G Danko
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| |
Collapse
|
13
|
Whole-genome methods to define DNA and histone accessibility and long-range interactions in chromatin. Biochem Soc Trans 2022; 50:199-212. [PMID: 35166326 PMCID: PMC9847230 DOI: 10.1042/bst20210959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/30/2021] [Accepted: 01/24/2022] [Indexed: 02/08/2023]
Abstract
Defining the genome-wide chromatin landscape has been a goal of experimentalists for decades. Here we review highlights of these efforts, from seminal experiments showing discontinuities in chromatin structure related to gene activation to extensions of these methods elucidating general features of chromatin related to gene states by exploiting deep sequencing methods. We also review chromatin conformational capture methods to identify patterns in long-range interactions between genomic loci.
Collapse
|
14
|
Chang JM, Weng YF, Chang WT, Lin FA, Cavalli G. HiCmapTools: a tool to access HiC contact maps. BMC Bioinformatics 2022; 23:64. [PMID: 35144531 PMCID: PMC8832839 DOI: 10.1186/s12859-022-04589-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 01/28/2022] [Indexed: 12/03/2022] Open
Abstract
Background With the development of HiC technology, more and more HiC sequencing data have been produced. Although there are dozens of packages that can turn sequencing data into contact maps, there is no appropriate tool to query contact maps in order to extract biological information from HiC datasets. Results We present HiCmapTools, a tool for biologists to efficiently calculate and analyze HiC maps. The complete program provides multi-query modes and analysis tools. We have validated its utility on two real biological questions: TAD loop and TAD intra-density. Conclusions HiCmapTools supports seven access options so that biologists can quantify contact frequency of the interest sites. The tool has been implemented in C++ and R and is freely available at https://github.com/changlabtw/hicmaptools and documented at https://hicmaptools.readthedocs.io/. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-022-04589-y.
Collapse
Affiliation(s)
- Jia-Ming Chang
- Department of Computer Science, National Chengchi University, 11605, Taipei City, Taiwan.
| | - Yi-Fu Weng
- Department of Computer Science, National Chengchi University, 11605, Taipei City, Taiwan
| | - Wei-Ting Chang
- Department of Computer Science, National Chengchi University, 11605, Taipei City, Taiwan
| | - Fu-An Lin
- Department of Computer Science, National Chengchi University, 11605, Taipei City, Taiwan
| | - Giacomo Cavalli
- Institute of Human Genetics, CNRS and University of Montpellier, Montpellier, France
| |
Collapse
|
15
|
Kim HS, Jeon Y, Jang YO, Lee H, Shin Y, Lee CW. Mammalian Ssu72 phosphatase preferentially considers tissue-specific actively transcribed gene expression by regulating RNA Pol II transcription. Theranostics 2022; 12:186-206. [PMID: 34987641 PMCID: PMC8690912 DOI: 10.7150/thno.62274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 10/26/2021] [Indexed: 11/12/2022] Open
Abstract
Reversible phosphorylation of the C-terminal domain (CTD) of RNA polymerase II (Pol II) is essential for gene expression control. How altering the phosphorylation of the CTD contributes to gene expression in mammalian systems remains poorly understood. Methods: Primary mouse embryonic fibroblasts, hepatocytes, and embryonic stem cells were isolated from conditional Ssu72f/f mice. To knockout the mouse Ssu72 gene, we infected the cells with adenoviruses of incorporated luciferase and Cre recombinase, respectively. RNA sequencing, ChIP sequencing, ChIP assay, immunoblot analyses, qRT-PCR assay, and immunostaining were performed to gain insights into the functional mechanisms of Ssu72 loss in Pol II dynamics. Results: Using primary cells isolated from Ssu72 conditional knockout and transgenic mice, we found that mammalian Ssu72-mediated transcriptional elongation rather than polyadenylation or RNA processing contributed to the transcriptional regulation of various genes. Depletion of Ssu72 resulted in aberrant Pol II pausing and elongation defects. Reduced transcriptional elongation efficiency tended to preferentially affect expression levels of actively transcribed genes in a tissue-specific manner. Furthermore, Ssu72 CTD phosphatase seemed to regulate the phosphorylation levels of CTD Ser2 and Thr4 through accurate modulation of P-TEFb activity and recruitment. Conclusions: Our findings demonstrate that mammalian Ssu72 contributes to the transcription of tissue-specific actively transcribed gene expression by regulating reciprocal phosphorylation of Pol II CTD.
Collapse
|
16
|
Kozisek T, Hamann A, Samuelson L, Fudolig M, Pannier AK. Comparison of promoter, DNA vector, and cationic carrier for efficient transfection of hMSCs from multiple donors and tissue sources. MOLECULAR THERAPY. NUCLEIC ACIDS 2021; 26:81-93. [PMID: 34513295 PMCID: PMC8413668 DOI: 10.1016/j.omtn.2021.06.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 06/25/2021] [Indexed: 01/22/2023]
Abstract
Human mesenchymal stem cells (hMSCs) are primary cells with high clinical relevance that could be enhanced through genetic modification. However, gene delivery, particularly through nonviral routes, is inefficient. To address the shortcomings of nonviral gene delivery to hMSCs, our lab has previously demonstrated that pharmacological "priming" of hMSCs with clinically approved drugs can increase transfection in hMSCs by modulating transfection-induced cytotoxicity. However, even with priming, hMSC transfection remains inefficient for clinical applications. This work takes a complementary approach to addressing the challenges of transfecting hMSCs by systematically investigating key transfection parameters for their effect on transgene expression. Specifically, we investigated two promoters (cytomegalovirus [CMV] and elongation factor 1 alpha), four DNA vectors (plasmid, plasmid with no F1 origin, minicircle, and mini-intronic plasmid), two cationic carriers (Lipofectamine 3000 and Turbofect), and four donors of hMSCs from two tissues (adipose and bone marrow) for efficient hMSC transfection. Following systematic comparison of each variable, we identified adipose-derived hMSCs transfected with mini-intronic plasmids containing the CMV promoter delivered using Lipofectamine 3000 as the parameters that produced the highest transfection levels. The data presented in this work can guide the development of other hMSC transfection systems with the goal of producing clinically relevant, genetically modified hMSCs.
Collapse
Affiliation(s)
- Tyler Kozisek
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Andrew Hamann
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Luke Samuelson
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Miguel Fudolig
- Department of Statistics, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Angela K. Pannier
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA
| |
Collapse
|
17
|
Kainth AS, Chowdhary S, Pincus D, Gross DS. Primordial super-enhancers: heat shock-induced chromatin organization in yeast. Trends Cell Biol 2021; 31:801-813. [PMID: 34001402 PMCID: PMC8448919 DOI: 10.1016/j.tcb.2021.04.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/30/2021] [Accepted: 04/09/2021] [Indexed: 01/29/2023]
Abstract
Specialized mechanisms ensure proper expression of critically important genes such as those specifying cell identity or conferring protection from environmental stress. Investigations of the heat shock response have been critical in elucidating basic concepts of transcriptional control. Recent studies demonstrate that in response to thermal stress, heat shock-responsive genes associate with high levels of transcriptional activators and coactivators and those in yeast intensely interact across and between chromosomes, coalescing into condensates. In mammalian cells, cell identity genes that are regulated by super-enhancers (SEs) are also densely occupied by transcriptional machinery that form phase-separated condensates. We suggest that the stress-remodeled yeast nucleome bears functional and structural resemblance to mammalian SEs, and will reveal fundamental mechanisms of gene control by transcriptional condensates.
Collapse
Affiliation(s)
- Amoldeep S Kainth
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA; Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Surabhi Chowdhary
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA; Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - David Pincus
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA.
| | - David S Gross
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA.
| |
Collapse
|
18
|
Pancholi A, Klingberg T, Zhang W, Prizak R, Mamontova I, Noa A, Sobucki M, Kobitski AY, Nienhaus GU, Zaburdaev V, Hilbert L. RNA polymerase II clusters form in line with surface condensation on regulatory chromatin. Mol Syst Biol 2021; 17:e10272. [PMID: 34569155 PMCID: PMC8474054 DOI: 10.15252/msb.202110272] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 08/26/2021] [Accepted: 09/10/2021] [Indexed: 12/15/2022] Open
Abstract
It is essential for cells to control which genes are transcribed into RNA. In eukaryotes, two major control points are recruitment of RNA polymerase II (Pol II) into a paused state, and subsequent pause release toward transcription. Pol II recruitment and pause release occur in association with macromolecular clusters, which were proposed to be formed by a liquid-liquid phase separation mechanism. How such a phase separation mechanism relates to the interaction of Pol II with DNA during recruitment and transcription, however, remains poorly understood. Here, we use live and super-resolution microscopy in zebrafish embryos to reveal Pol II clusters with a large variety of shapes, which can be explained by a theoretical model in which regulatory chromatin regions provide surfaces for liquid-phase condensation at concentrations that are too low for canonical liquid-liquid phase separation. Model simulations and chemical perturbation experiments indicate that recruited Pol II contributes to the formation of these surface-associated condensates, whereas elongating Pol II is excluded from these condensates and thereby drives their unfolding.
Collapse
Affiliation(s)
- Agnieszka Pancholi
- Zoological InstituteDepartment of Systems Biology and BioinformaticsKarlsruhe Institute of TechnologyKarlsruheGermany
- Institute of Biological and Chemical Systems—Biological Information ProcessingKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
| | - Tim Klingberg
- Department of BiologyFriedrich‐Alexander‐Universität Erlangen‐NürnbergErlangenGermany
- Max‐Planck‐Zentrum für Physik und MedizinErlangenGermany
| | - Weichun Zhang
- Institute of Applied PhysicsKarlsruhe Institute of TechnologyKarlsruheGermany
- Institute of NanotechnologyKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
| | - Roshan Prizak
- Institute of Biological and Chemical Systems—Biological Information ProcessingKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
| | - Irina Mamontova
- Institute of Biological and Chemical Systems—Biological Information ProcessingKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
| | - Amra Noa
- Institute of Biological and Chemical Systems—Biological Information ProcessingKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
| | - Marcel Sobucki
- Institute of Biological and Chemical Systems—Biological Information ProcessingKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
| | - Andrei Yu Kobitski
- Institute of Applied PhysicsKarlsruhe Institute of TechnologyKarlsruheGermany
| | - Gerd Ulrich Nienhaus
- Institute of Biological and Chemical Systems—Biological Information ProcessingKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
- Institute of Applied PhysicsKarlsruhe Institute of TechnologyKarlsruheGermany
- Institute of NanotechnologyKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
- Department of PhysicsUniversity of Illinois at Urbana‐ChampaignUrbanaILUSA
| | - Vasily Zaburdaev
- Department of BiologyFriedrich‐Alexander‐Universität Erlangen‐NürnbergErlangenGermany
- Max‐Planck‐Zentrum für Physik und MedizinErlangenGermany
| | - Lennart Hilbert
- Zoological InstituteDepartment of Systems Biology and BioinformaticsKarlsruhe Institute of TechnologyKarlsruheGermany
- Institute of Biological and Chemical Systems—Biological Information ProcessingKarlsruhe Institute of TechnologyEggenstein‐LeopoldshafenGermany
| |
Collapse
|
19
|
Liu J, Hansen D, Eck E, Kim YJ, Turner M, Alamos S, Garcia HG. Real-time single-cell characterization of the eukaryotic transcription cycle reveals correlations between RNA initiation, elongation, and cleavage. PLoS Comput Biol 2021; 17:e1008999. [PMID: 34003867 PMCID: PMC8162642 DOI: 10.1371/journal.pcbi.1008999] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 05/28/2021] [Accepted: 04/23/2021] [Indexed: 12/23/2022] Open
Abstract
The eukaryotic transcription cycle consists of three main steps: initiation, elongation, and cleavage of the nascent RNA transcript. Although each of these steps can be regulated as well as coupled with each other, their in vivo dissection has remained challenging because available experimental readouts lack sufficient spatiotemporal resolution to separate the contributions from each of these steps. Here, we describe a novel application of Bayesian inference techniques to simultaneously infer the effective parameters of the transcription cycle in real time and at the single-cell level using a two-color MS2/PP7 reporter gene and the developing fruit fly embryo as a case study. Our method enables detailed investigations into cell-to-cell variability in transcription-cycle parameters as well as single-cell correlations between these parameters. These measurements, combined with theoretical modeling, suggest a substantial variability in the elongation rate of individual RNA polymerase molecules. We further illustrate the power of this technique by uncovering a novel mechanistic connection between RNA polymerase density and nascent RNA cleavage efficiency. Thus, our approach makes it possible to shed light on the regulatory mechanisms in play during each step of the transcription cycle in individual, living cells at high spatiotemporal resolution.
Collapse
Affiliation(s)
- Jonathan Liu
- Department of Physics, University of California at Berkeley, Berkeley, California, United States of America
| | - Donald Hansen
- Institute of Pharmacy and Molecular Biotechnology, University of Heidelberg, Heidelberg, Germany
| | - Elizabeth Eck
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, California, United States of America
| | - Yang Joon Kim
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, California, United States of America
| | - Meghan Turner
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, California, United States of America
| | - Simon Alamos
- Department of Plant and Microbial Biology, University of California at Berkeley, Berkeley, California, United States of America
| | - Hernan G. Garcia
- Department of Physics, University of California at Berkeley, Berkeley, California, United States of America
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, California, United States of America
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California, United States of America
- Institute for Quantitative Biosciences-QB3, University of California at Berkeley, Berkeley, California, United States of America
| |
Collapse
|
20
|
Zhurkin VB, Norouzi D. Topological polymorphism of nucleosome fibers and folding of chromatin. Biophys J 2021; 120:577-585. [PMID: 33460599 PMCID: PMC7896024 DOI: 10.1016/j.bpj.2021.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/28/2020] [Accepted: 01/07/2021] [Indexed: 01/19/2023] Open
Abstract
We discuss recent observations of polymorphic chromatin packaging at the oligonucleosomal level and compare them with computer simulations. Our computations reveal two topologically different families of two-start 30-nm fiber conformations distinguished by the linker length L; fibers with L ≈ 10n and L ≈ 10n+5 basepairs have DNA linking numbers per nucleosome of ΔLk ≈ -1.5 and -1.0, respectively (where n is a natural number). Although fibers with ΔLk ≈ -1.5 were observed earlier, the topoisomer with ΔLk ≈ -1.0 is novel. These predictions were confirmed experimentally for circular nucleosome arrays with precisely positioned nucleosomes. We suggest that topological polymorphism of chromatin may play a role in transcription, with the {10n+5} fibers producing transcriptionally competent chromatin structures. This hypothesis is consistent with available data for yeast and, partially, for fly. We show that both fiber topoisomers (with ΔLk ≈ -1.5 and -1.0) have to be taken into account to interpret experimental data obtained using new techniques: genome-wide Micro-C, Hi-CO, and RICC-seq, as well as self-association of nucleosome arrays in vitro. The relative stability of these topoisomers is likely to depend on epigenetic histone modifications modulating the strength of internucleosome interactions. Potentially, our findings may reflect a general tendency of functionally distinct parts of the genome to retain topologically different higher-order structures.
Collapse
Affiliation(s)
- Victor B Zhurkin
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
| | - Davood Norouzi
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
| |
Collapse
|
21
|
Al-Husini N, Medler S, Ansari A. Crosstalk of promoter and terminator during RNA polymerase II transcription cycle. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194657. [PMID: 33246184 DOI: 10.1016/j.bbagrm.2020.194657] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/16/2022]
Abstract
The transcription cycle of RNAPII is comprised of three consecutive steps; initiation, elongation and termination. It has been assumed that the initiation and termination steps occur in spatial isolation, essentially as independent events. A growing body of evidence, however, has challenged this dogma. First, factors involved in initiation and termination exhibit both a genetic and a physical interaction during transcription. Second, the initiation and termination factors have been found to occupy both ends of a transcribing gene. Third, physical interaction of initiation and termination factors occupying distal ends of a gene sometime results in the entire terminator region of a genes looping back and contact its cognate promoter, thereby forming a looped gene architecture during transcription. A logical interpretation of these findings is that the initiation and termination steps of transcription do not occur in isolation. There is extensive communication of factors occupying promoter and terminator ends of a gene during transcription cycle. This review entails a discussion of the promoter-terminator crosstalk and its implication in the context of transcription.
Collapse
Affiliation(s)
- Nadra Al-Husini
- Department of Biological Science, Wayne State University, Detroit, MI, United States of America
| | - Scott Medler
- Department of Biological Science, Wayne State University, Detroit, MI, United States of America
| | - Athar Ansari
- Department of Biological Science, Wayne State University, Detroit, MI, United States of America.
| |
Collapse
|
22
|
Gagliardi D, Manavella PA. Short-range regulatory chromatin loops in plants. THE NEW PHYTOLOGIST 2020; 228:466-471. [PMID: 32353900 DOI: 10.1111/nph.16632] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/14/2020] [Indexed: 06/11/2023]
Abstract
In all eukaryotic organisms, gene expression correlates with the condensation state of the chromatin. Highly packed genome regions, known as heterochromatins, are associated with repressed loci, whereas euchromatic regions represent a relaxed state of the chromatin actively transcribed. However, even in these active regions, associations between chromatin domains dynamically modify genome topology and alter gene expression. Long-range interaction within and between chromosomes determines chromatin domains that help to coordinate transcriptional events. On the other hand, short-range chromatin interactions emerged as dynamic mechanisms regulating the expression of specific loci. Our current capacity to decipher genome topology at high resolution allowed us to identify numerous cases of short-range regulatory chromatin interactions, which are reviewed in this Insight article.
Collapse
Affiliation(s)
- Delfina Gagliardi
- Facultad de Bioquímica y Ciencias Biológicas, Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Universidad Nacional del Litoral, 3000, Santa Fe, Argentina
| | - Pablo A Manavella
- Facultad de Bioquímica y Ciencias Biológicas, Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Universidad Nacional del Litoral, 3000, Santa Fe, Argentina
| |
Collapse
|
23
|
Tellier M, Maudlin I, Murphy S. Transcription and splicing: A two-way street. WILEY INTERDISCIPLINARY REVIEWS. RNA 2020; 11:e1593. [PMID: 32128990 DOI: 10.1002/wrna.1593] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 12/18/2019] [Accepted: 02/12/2020] [Indexed: 12/11/2022]
Abstract
RNA synthesis by RNA polymerase II and RNA processing are closely coupled during the transcription cycle of protein-coding genes. This coupling affords opportunities for quality control and regulation of gene expression and the effects can go in both directions. For example, polymerase speed can affect splice site selection and splicing can increase transcription and affect the chromatin landscape. Here we review the many ways that transcription and splicing influence one another, including how splicing "talks back" to transcription. We will also place the connections between transcription and splicing in the context of other RNA processing events that define the exons that will make up the final mRNA. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.
Collapse
Affiliation(s)
- Michael Tellier
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Isabella Maudlin
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Shona Murphy
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| |
Collapse
|
24
|
Transcriptional control of gene expression in Pichia pastoris by manipulation of terminators. Appl Microbiol Biotechnol 2020; 104:7841-7851. [DOI: 10.1007/s00253-020-10785-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/03/2020] [Accepted: 07/13/2020] [Indexed: 12/11/2022]
|
25
|
First Come, First Served: Sui Generis Features of the First Intron. PLANTS 2020; 9:plants9070911. [PMID: 32707681 PMCID: PMC7411622 DOI: 10.3390/plants9070911] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/15/2020] [Accepted: 07/17/2020] [Indexed: 02/07/2023]
Abstract
Most of the transcribed genes in eukaryotic cells are interrupted by intervening sequences called introns that are co-transcriptionally removed from nascent messenger RNA through the process of splicing. In Arabidopsis, 79% of genes contain introns and more than 60% of intron-containing genes undergo alternative splicing (AS), which ostensibly is considered to increase protein diversity as one of the intrinsic mechanisms for fitness to the varying environment or the internal developmental program. In addition, recent findings have prevailed in terms of overlooked intron functions. Here, we review recent progress in the underlying mechanisms of intron function, in particular by focusing on unique features of the first intron that is located in close proximity to the transcription start site. The distinct deposition of epigenetic marks and nucleosome density on the first intronic DNA sequence, the impact of the first intron on determining the transcription start site and elongation of its own expression (called intron-mediated enhancement, IME), translation control in 5′-UTR, and the new mechanism of the trans-acting function of the first intron in regulating gene expression at the post-transcriptional level are summarized.
Collapse
|
26
|
Wosika V, Pelet S. Single-particle imaging of stress-promoters induction reveals the interplay between MAPK signaling, chromatin and transcription factors. Nat Commun 2020; 11:3171. [PMID: 32576833 PMCID: PMC7311541 DOI: 10.1038/s41467-020-16943-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 06/02/2020] [Indexed: 01/25/2023] Open
Abstract
Precise regulation of gene expression in response to environmental changes is crucial for cell survival, adaptation and proliferation. In eukaryotic cells, extracellular signal integration is often carried out by Mitogen-Activated Protein Kinases (MAPK). Despite a robust MAPK signaling activity, downstream gene expression can display a great variability between single cells. Using a live mRNA reporter, here we monitor the dynamics of transcription in Saccharomyces cerevisiae upon hyper-osmotic shock. We find that the transient activity of the MAPK Hog1 opens a temporal window where stress-response genes can be activated. We show that the first minutes of Hog1 activity are essential to control the activation of a promoter. Chromatin repression on a locus slows down this transition and contributes to the variability in gene expression, while binding of transcription factors increases the level of transcription. However, soon after Hog1 activity peaks, negative regulators promote chromatin closure of the locus and transcription progressively stops.
Collapse
Affiliation(s)
- Victoria Wosika
- Department of Fundamental Microbiology, University of Lausanne, 1015, Lausanne, Switzerland
| | - Serge Pelet
- Department of Fundamental Microbiology, University of Lausanne, 1015, Lausanne, Switzerland.
| |
Collapse
|
27
|
Hsieh THS, Cattoglio C, Slobodyanyuk E, Hansen AS, Rando OJ, Tjian R, Darzacq X. Resolving the 3D Landscape of Transcription-Linked Mammalian Chromatin Folding. Mol Cell 2020; 78:539-553.e8. [PMID: 32213323 PMCID: PMC7703524 DOI: 10.1016/j.molcel.2020.03.002] [Citation(s) in RCA: 323] [Impact Index Per Article: 80.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 01/28/2020] [Accepted: 03/02/2020] [Indexed: 01/31/2023]
Abstract
Whereas folding of genomes at the large scale of epigenomic compartments and topologically associating domains (TADs) is now relatively well understood, how chromatin is folded at finer scales remains largely unexplored in mammals. Here, we overcome some limitations of conventional 3C-based methods by using high-resolution Micro-C to probe links between 3D genome organization and transcriptional regulation in mouse stem cells. Combinatorial binding of transcription factors, cofactors, and chromatin modifiers spatially segregates TAD regions into various finer-scale structures with distinct regulatory features including stripes, dots, and domains linking promoters-to-promoters (P-P) or enhancers-to-promoters (E-P) and bundle contacts between Polycomb regions. E-P stripes extending from the edge of domains predominantly link co-expressed loci, often in the absence of CTCF and cohesin occupancy. Acute inhibition of transcription disrupts these gene-related folding features without altering higher-order chromatin structures. Our study uncovers previously obscured finer-scale genome organization, establishing functional links between chromatin folding and gene regulation.
Collapse
Affiliation(s)
- Tsung-Han S Hsieh
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Li Ka Shing Center for Biomedical and Health Sciences, University of California, Berkeley, Berkeley, CA 94720, USA; CIRM Center of Excellence, University of California, Berkeley, Berkeley, CA 94720, USA; Center for Computational Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Claudia Cattoglio
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Li Ka Shing Center for Biomedical and Health Sciences, University of California, Berkeley, Berkeley, CA 94720, USA; CIRM Center of Excellence, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Elena Slobodyanyuk
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Li Ka Shing Center for Biomedical and Health Sciences, University of California, Berkeley, Berkeley, CA 94720, USA; CIRM Center of Excellence, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Anders S Hansen
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Li Ka Shing Center for Biomedical and Health Sciences, University of California, Berkeley, Berkeley, CA 94720, USA; CIRM Center of Excellence, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Oliver J Rando
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Robert Tjian
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Li Ka Shing Center for Biomedical and Health Sciences, University of California, Berkeley, Berkeley, CA 94720, USA; CIRM Center of Excellence, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Li Ka Shing Center for Biomedical and Health Sciences, University of California, Berkeley, Berkeley, CA 94720, USA; CIRM Center of Excellence, University of California, Berkeley, Berkeley, CA 94720, USA; Center for Computational Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
| |
Collapse
|
28
|
Campbell M, Izumiya Y. PAN RNA: transcriptional exhaust from a viral engine. J Biomed Sci 2020; 27:41. [PMID: 32143650 PMCID: PMC7060532 DOI: 10.1186/s12929-020-00637-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/03/2020] [Indexed: 02/06/2023] Open
Abstract
Kaposi’s sarcoma-associated herpesvirus (KSHV), also designated human herpesvirus 8 (HHV-8), has been linked to Kaposi’s sarcoma, as well as to primary effusion lymphoma (PEL), and a subset of multicentric Castleman’s disease. KSHV genomes are maintained as episomes within infected cells and the virus exhibits a biphasic life cycle consisting of a life-long latent phase during which only a few viral genes are expressed and no viral progeny are produced and a transient lytic reactivation phase, in which a full repertoire of ~ 80 lytic genes are activated in a temporally regulated manner culminating in the release of new virions. Lytic replication is initiated by a single viral protein, K-Rta (ORF50), which activates more than 80 viral genes from multiple resident viral episomes (i.e., viral chromosomes). One of the major targets of K-Rta is a long non-coding nuclear RNA, PAN RNA (polyadenylated nuclear RNA), a lncRNA that accumulates to exceedingly high levels in the nucleus during viral reactivation. K-Rta directly binds to the PAN RNA promoter and robustly activates PAN RNA expression. Although PAN RNA has been known for over 20 years, its role in viral replication is still incompletely understood. In this perspective, we will briefly review the current understanding of PAN RNA and then describe our current working model of this RNA. The model is based on our observations concerning events that occur during KSHV lytic reactivation including (i) a marked accumulation of RNA Pol II at the PAN promoter, (ii) genomic looping emanating from the PAN locus, (iii) interaction of a second viral lytic protein (ORF57) with K-Rta, PAN RNA and RNA Pol II, (iv) the essential requirement for PAN RNA expression in cis for optimal transcriptional execution needed for the entire lytic program, and (v) ORF57 recruitment of RNA Pol II to the PAN genomic locus. Together our results generate a model in which the PAN locus serves as a hub for sequestration/trapping of the cellular transcriptional machinery proximal to viral episomes. Sequestration at the PAN locus facilitates high levels of viral transcription throughout the viral genome during lytic replication. ORF57 acts as a transcription-dependent transactivator at the PAN locus by binding to both Rta and PAN to locally trap RNA Pol II. The resulting accumulation of high levels of nuclear PAN RNA created by this process is an inducible enhancer-derived (eRNA) by-product that litters the infected cell nucleus.
Collapse
Affiliation(s)
- Mel Campbell
- Department of Dermatology and UC Davis Comprehensive Cancer Center, University of California Davis School of Medicine, 4645 2nd Avenue Research III Room 3100, Sacramento, CA, 95817, USA.
| | - Yoshihiro Izumiya
- Department of Dermatology and UC Davis Comprehensive Cancer Center, University of California Davis School of Medicine, 4645 2nd Avenue Research III Room 3100, Sacramento, CA, 95817, USA.
| |
Collapse
|
29
|
Shipony Z, Marinov GK, Swaffer MP, Sinnott-Armstrong NA, Skotheim JM, Kundaje A, Greenleaf WJ. Long-range single-molecule mapping of chromatin accessibility in eukaryotes. Nat Methods 2020; 17:319-327. [PMID: 32042188 PMCID: PMC7968351 DOI: 10.1038/s41592-019-0730-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 12/22/2019] [Indexed: 02/06/2023]
Abstract
Mapping open chromatin regions has emerged as a widely used tool for identifying active regulatory elements in eukaryotes. However, existing approaches, limited by reliance on DNA fragmentation and short-read sequencing, cannot provide information about large-scale chromatin states or reveal coordination between the states of distal regulatory elements. We have developed a method for profiling the accessibility of individual chromatin fibers, a single-molecule long-read accessible chromatin mapping sequencing assay (SMAC-seq), enabling the simultaneous, high-resolution, single-molecule assessment of chromatin states at multikilobase length scales. Our strategy is based on combining the preferential methylation of open chromatin regions by DNA methyltransferases with low sequence specificity, in this case EcoGII, an N6-methyladenosine (m6A) methyltransferase, and the ability of nanopore sequencing to directly read DNA modifications. We demonstrate that aggregate SMAC-seq signals match bulk-level accessibility measurements, observe single-molecule nucleosome and transcription factor protection footprints, and quantify the correlation between chromatin states of distal genomic elements.
Collapse
Affiliation(s)
- Zohar Shipony
- Department of Genetics, Stanford University, Stanford, CA, USA
| | | | | | | | - Jan M Skotheim
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Anshul Kundaje
- Department of Genetics, Stanford University, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
| | - William J Greenleaf
- Department of Genetics, Stanford University, Stanford, CA, USA.
- Department of Applied Physics, Stanford University, Stanford, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
| |
Collapse
|
30
|
|
31
|
Wang PH, Kumar S, Zeng J, McEwan R, Wright TR, Gupta M. Transcription Terminator-Mediated Enhancement in Transgene Expression in Maize: Preponderance of the AUGAAU Motif Overlapping With Poly(A) Signals. FRONTIERS IN PLANT SCIENCE 2020; 11:570778. [PMID: 33178242 PMCID: PMC7591816 DOI: 10.3389/fpls.2020.570778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/11/2020] [Indexed: 05/08/2023]
Abstract
The selection of transcription terminators (TTs) for pairing with high expressing constitutive promoters in chimeric constructs is crucial to deliver optimal transgene expression in plants. In this study, the use of the native combinations of four polyubiquitin gene promoters and corresponding TTs resulted in up to >3-fold increase in transgene expression in maize. Of the eight polyubiquitin promoter and TT regulatory elements utilized, seven were novel and identified from the polyubiquitin genes of Brachypodium distachyon, Setaria italica, and Zea mays. Furthermore, gene expression driven by the Cassava mosaic virus promoter was studied by pairing the promoter with distinct TTs derived from the high expressing genes of Arabidopsis. Of the three TTs studied, the polyubiquitin10 gene TT produced the highest transgene expression in maize. Polyadenylation patterns and mRNA abundance from eight distinct TTs were analyzed using 3'-RACE and next-generation sequencing. The results exhibited one to three unique polyadenylation sites in the TTs. The poly(A) site patterns for the StPinII TT were consistent when the same TT was deployed in chimeric constructs irrespective of the reporter gene and promoter used. Distal to the poly(A) sites, putative polyadenylation signals were identified in the near-upstream regions of the TTs based on previously reported mutagenesis and bioinformatics studies in rice and Arabidopsis. The putative polyadenylation signals were 9 to 11 nucleotides in length. Six of the eight TTs contained the putative polyadenylation signals that were overlaps of either canonical AAUAAA or AAUAAA-like polyadenylation signals and AUGAAU, a top-ranking-hexamer of rice and Arabidopsis gene near-upstream regions. Three of the polyubiquitin gene TTs contained the identical 9-nucleotide overlap, AUGAAUAAG, underscoring the functional significance of such overlaps in mRNA 3' end processing. In addition to identifying new combinations of regulatory elements for high constitutive trait gene expression in maize, this study demonstrated the importance of TTs for optimizing gene expression in plants. Learning from this study could be applied to other dicotyledonous and monocotyledonous plant species for transgene expression. Research on TTs is not limited to transgene expression but could be extended to the introduction of appropriate mutations into TTs via genome editing, paving the way for expression modulation of endogenous genes.
Collapse
Affiliation(s)
- Po-Hao Wang
- Applied Science & Technology, Corteva Agriscience, Johnston, IA, United States
| | - Sandeep Kumar
- Applied Science & Technology, Corteva Agriscience, Johnston, IA, United States
- *Correspondence: Sandeep Kumar,
| | - Jia Zeng
- Data Science & Informatics, Corteva Agriscience, Indianapolis, IN, United States
| | - Robert McEwan
- Applied Science & Technology, Corteva Agriscience, Johnston, IA, United States
| | - Terry R. Wright
- Trait Discovery, Corteva Agriscience, Indianapolis, IN, United States
| | - Manju Gupta
- Trait Product Development, Dow Agrosciences, Indianapolis, IN, United States
| |
Collapse
|
32
|
Methods for mapping three-dimensional genome architecture. Methods 2020; 170:1-3. [PMID: 31669352 DOI: 10.1016/j.ymeth.2019.10.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
33
|
Achar YJ, Adhil M, Choudhary R, Gilbert N, Foiani M. Negative supercoil at gene boundaries modulates gene topology. Nature 2020; 577:701-705. [PMID: 31969709 DOI: 10.1038/s41586-020-1934-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 11/25/2019] [Indexed: 11/08/2022]
Abstract
Transcription challenges the integrity of replicating chromosomes by generating topological stress and conflicts with forks1,2. The DNA topoisomerases Top1 and Top2 and the HMGB family protein Hmo1 assist DNA replication and transcription3-6. Here we describe the topological architecture of genes in Saccharomyces cerevisiae during the G1 and S phases of the cell cycle. We found under-wound DNA at gene boundaries and over-wound DNA within coding regions. This arrangement does not depend on Pol II or S phase. Top2 and Hmo1 preserve negative supercoil at gene boundaries, while Top1 acts at coding regions. Transcription generates RNA-DNA hybrids within coding regions, independently of fork orientation. During S phase, Hmo1 protects under-wound DNA from Top2, while Top2 confines Pol II and Top1 at coding units, counteracting transcription leakage and aberrant hybrids at gene boundaries. Negative supercoil at gene boundaries prevents supercoil diffusion and nucleosome repositioning at coding regions. DNA looping occurs at Top2 clusters. We propose that Hmo1 locks gene boundaries in a cruciform conformation and, with Top2, modulates the architecture of genes that retain the memory of the topological arrangements even when transcription is repressed.
Collapse
MESH Headings
- Chromatin Assembly and Disassembly
- DNA Replication
- DNA Topoisomerases, Type I/metabolism
- DNA Topoisomerases, Type II/genetics
- DNA Topoisomerases, Type II/metabolism
- DNA, Cruciform/chemistry
- DNA, Cruciform/genetics
- DNA, Cruciform/metabolism
- DNA, Fungal/chemistry
- DNA, Fungal/genetics
- DNA, Fungal/metabolism
- DNA, Superhelical/chemistry
- DNA, Superhelical/genetics
- DNA, Superhelical/metabolism
- G1 Phase
- Gene Expression Regulation, Fungal
- Genes, Fungal
- High Mobility Group Proteins/metabolism
- Mutation
- Nucleic Acid Hybridization
- Nucleosomes/chemistry
- Nucleosomes/genetics
- Nucleosomes/metabolism
- Open Reading Frames/genetics
- RNA Polymerase II/genetics
- RNA Polymerase II/metabolism
- RNA, Fungal/chemistry
- RNA, Fungal/genetics
- RNA, Fungal/metabolism
- S Phase
- Saccharomyces cerevisiae/cytology
- Saccharomyces cerevisiae/enzymology
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae Proteins/metabolism
- Transcription, Genetic
Collapse
Affiliation(s)
| | - Mohamood Adhil
- IFOM (Fondazione Istituto FIRC di Oncologia Molecolare), Milan, Italy
| | - Ramveer Choudhary
- IFOM (Fondazione Istituto FIRC di Oncologia Molecolare), Milan, Italy
| | - Nick Gilbert
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Marco Foiani
- IFOM (Fondazione Istituto FIRC di Oncologia Molecolare), Milan, Italy.
- Università degli Studi di Milano, Milan, Italy.
| |
Collapse
|
34
|
Allepuz-Fuster P, O'Brien MJ, González-Polo N, Pereira B, Dhoondia Z, Ansari A, Calvo O. RNA polymerase II plays an active role in the formation of gene loops through the Rpb4 subunit. Nucleic Acids Res 2019; 47:8975-8987. [PMID: 31304538 PMCID: PMC6753479 DOI: 10.1093/nar/gkz597] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/27/2019] [Accepted: 06/29/2019] [Indexed: 01/19/2023] Open
Abstract
Gene loops are formed by the interaction of initiation and termination factors occupying the distal ends of a gene during transcription. RNAPII is believed to affect gene looping indirectly owing to its essential role in transcription. The results presented here, however, demonstrate a direct role of RNAPII in gene looping through the Rpb4 subunit. 3C analysis revealed that gene looping is abolished in the rpb4Δ mutant. In contrast to the other looping-defective mutants, rpb4Δ cells do not exhibit a transcription termination defect. RPB4 overexpression, however, rescued the transcription termination and gene looping defect of sua7-1, a mutant of TFIIB. Furthermore, RPB4 overexpression rescued the ssu72-2 gene looping defect, while SSU72 overexpression restored the formation of gene loops in rpb4Δ cells. Interestingly, the interaction of TFIIB with Ssu72 is compromised in rpb4Δ cells. These results suggest that the TFIIB-Ssu72 interaction, which is critical for gene loop formation, is facilitated by Rpb4. We propose that Rpb4 is promoting the transfer of RNAPII from the terminator to the promoter for reinitiation of transcription through TFIIB-Ssu72 mediated gene looping.
Collapse
Affiliation(s)
| | - Michael J O'Brien
- Department of Biological Science. Wayne State University. Detroit, MI 48202, USA
| | | | - Bianca Pereira
- Department of Biological Science. Wayne State University. Detroit, MI 48202, USA
| | - Zuzer Dhoondia
- Department of Biological Science. Wayne State University. Detroit, MI 48202, USA
| | - Athar Ansari
- Department of Biological Science. Wayne State University. Detroit, MI 48202, USA
| | - Olga Calvo
- Instituto de Biología Funcional y Genómica, CSIC-USAL, Salamanca, Spain
| |
Collapse
|
35
|
Hasegawa Y, Struhl K. Promoter-specific dynamics of TATA-binding protein association with the human genome. Genome Res 2019; 29:1939-1950. [PMID: 31732535 PMCID: PMC6886507 DOI: 10.1101/gr.254466.119] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 10/07/2019] [Indexed: 12/11/2022]
Abstract
Transcription factor binding to target sites in vivo is a dynamic process that involves cycles of association and dissociation, with individual proteins differing in their binding dynamics. The dynamics at individual sites on a genomic scale have been investigated in yeast cells, but comparable experiments have not been done in multicellular eukaryotes. Here, we describe a tamoxifen-inducible, time-course ChIP-seq approach to measure transcription factor binding dynamics at target sites throughout the human genome. As observed in yeast cells, the TATA-binding protein (TBP) typically displays rapid turnover at RNA polymerase (Pol) II-transcribed promoters, slow turnover at Pol III promoters, and very slow turnover at the Pol I promoter. Turnover rates vary widely among Pol II promoters in a manner that does not correlate with the level of TBP occupancy. Human Pol II promoters with slow TBP dissociation preferentially contain a TATA consensus motif, support high transcriptional activity of downstream genes, and are linked with specific activators and chromatin remodelers. These properties of human promoters with slow TBP turnover differ from those of yeast promoters with slow turnover. These observations suggest that TBP binding dynamics differentially affect promoter function and gene expression, possibly at the level of transcriptional reinitiation/bursting.
Collapse
Affiliation(s)
- Yuko Hasegawa
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Human Genetics, University of Chicago, Chicago, Illinois 60637, USA
| | - Kevin Struhl
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA
| |
Collapse
|
36
|
Chromosome conformation capture that detects novel cis- and trans-interactions in budding yeast. Methods 2019; 170:4-16. [PMID: 31252061 DOI: 10.1016/j.ymeth.2019.06.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/17/2019] [Accepted: 06/21/2019] [Indexed: 11/22/2022] Open
Abstract
Chromosome Conformation Capture (3C) has emerged as a powerful approach for revealing the conformation and features of three-dimensional (3D) genomic organization. Yet attainment of higher resolution in organisms with compact genomes presents a challenge. Here, we describe modifications in the 3C technique that substantially enhance its resolution and sensitivity when applied to the 3D genome of budding yeast. Keys to our approach include use of a 4 bp cutter, Taq I, for cleaving the genome and quantitative PCR for measuring the frequency of ligation. Most importantly, we normalize the percent digestion at each restriction site to account for variation in accessibility of local chromatin structure under a given physiological condition. This strategy has led to the detection of physical interactions between regulatory elements and gene coding regions as well as intricate, stimulus-specific interchromosomal interactions between activated genes. We provide an algorithm that incorporates these and other modifications and allows quantitative determination of chromatin interaction frequencies in yeast under any physiological condition.
Collapse
|
37
|
Stone JK, Kim JH, Vukadin L, Richard A, Giannini HK, Lim STS, Tan M, Ahn EYE. Hypoxia induces cancer cell-specific chromatin interactions and increases MALAT1 expression in breast cancer cells. J Biol Chem 2019; 294:11213-11224. [PMID: 31167784 DOI: 10.1074/jbc.ra118.006889] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 05/29/2019] [Indexed: 12/18/2022] Open
Abstract
Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a long noncoding RNA overexpressed in various cancers that promotes cell growth and metastasis. Although hypoxia has been shown to up-regulate MALAT1, only hypoxia-inducible factors (HIFs) have been implicated in activation of the MALAT1 promoter in specific cell types and other molecular mechanisms associated with hypoxia-mediated MALAT1 up-regulation remain largely unknown. Here, we demonstrate that hypoxia induces cancer cell-specific chromatin-chromatin interactions between newly identified enhancer-like cis-regulatory elements present at the MALAT1 locus. We show that hypoxia-mediated up-regulation of MALAT1 as well as its antisense strand TALAM1 occurs in breast cancer cells, but not in nontumorigenic mammary epithelial cells. Our analyses on the MALAT1 genomic locus discovered three novel putative enhancers that are located upstream and downstream of the MALAT1 gene body. We found that parts of these putative enhancers are epigenetically modified to a more open chromatin state under hypoxia in breast cancer cells. Furthermore, our chromosome conformation capture experiment demonstrated that noncancerous cells and breast cancer cells exhibit different interaction profiles under both normoxia and hypoxia, and only breast cancer cells gain specific chromatin interactions under hypoxia. Although the HIF-2α protein can enhance the interaction between the promoter and the putative 3' enhancer, the gain of chromatin interactions associated with other upstream elements, such as putative -7 and -20 kb enhancers, were HIF-independent events. Collectively, our study demonstrates that cancer cell-specific chromatin-chromatin interactions are formed at the MALAT1 locus under hypoxia, implicating a novel mechanism of MALAT1 regulation in cancer.
Collapse
Affiliation(s)
- Joshua K Stone
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama 36604
| | - Jung-Hyun Kim
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama 36604
| | - Lana Vukadin
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama 36604
| | - Alexander Richard
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama 36604
| | - Hannah K Giannini
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama 36604
| | - Ssang-Taek Steve Lim
- Department of Biochemistry and Molecular Biology, College of Medicine, University of South Alabama, Mobile, Alabama 36688
| | - Ming Tan
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama 36604.,Department of Biochemistry and Molecular Biology, College of Medicine, University of South Alabama, Mobile, Alabama 36688
| | - Eun-Young Erin Ahn
- Mitchell Cancer Institute, University of South Alabama, Mobile, Alabama 36604 .,Department of Biochemistry and Molecular Biology, College of Medicine, University of South Alabama, Mobile, Alabama 36688
| |
Collapse
|
38
|
Ahmed MS, Ikram S, Rasool A, Li C. Design and construction of short synthetic terminators for β-amyrin production in Saccharomyces cerevisiae. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.03.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
39
|
Lazniewski M, Dawson WK, Rusek AM, Plewczynski D. One protein to rule them all: The role of CCCTC-binding factor in shaping human genome in health and disease. Semin Cell Dev Biol 2019; 90:114-127. [PMID: 30096365 PMCID: PMC6642822 DOI: 10.1016/j.semcdb.2018.08.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 08/06/2018] [Indexed: 12/12/2022]
Abstract
The eukaryotic genome, constituting several billion base pairs, must be contracted to fit within the volume of a nucleus where the diameter is on the scale of μm. The 3D structure and packing of such a long sequence cannot be left to pure chance, as DNA must be efficiently used for its primary roles as a matrix for transcription and replication. In recent years, methods like chromatin conformation capture (including 3C, 4C, Hi-C, ChIA-PET and Multi-ChIA) and optical microscopy have advanced substantially and have shed new light on how eukaryotic genomes are hierarchically organized; first into 10-nm fiber, next into DNA loops, topologically associated domains and finally into interphase or mitotic chromosomes. This knowledge has allowed us to revise our understanding regarding the mechanisms governing the process of DNA organization. Mounting experimental evidence suggests that the key element in the formation of loops is the binding of the CCCTC-binding factor (CTCF) to DNA; a protein that can be referred to as the chief organizer of the genome. However, CTCF does not work alone but in cooperation with other proteins, such as cohesin or Yin Yang 1 (YY1). In this short review, we briefly describe our current understanding of the structure of eukaryotic genomes, how they are established and how the formation of DNA loops can influence gene expression. We discuss the recent discoveries describing the 3D structure of the CTCF-DNA complex and the role of CTCF in establishing genome structure. Finally, we briefly explain how various genetic disorders might arise as a consequence of mutations in the CTCF target sequence or alteration of genomic imprinting.
Collapse
Affiliation(s)
- Michal Lazniewski
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland; Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02-097 Warsaw, Poland
| | - Wayne K Dawson
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland; Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 103-8657, Japan
| | - Anna Maria Rusek
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland; Clinical Molecular Biology Department, Medical University of Bialystok, Bialystok, Poland
| | - Dariusz Plewczynski
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland; Centre for Innovative Research, Medical University of Bialystok, Bialystok, Poland; Faculty of Mathematics and Information Science, Warsaw University of Technology, Warsaw, Poland.
| |
Collapse
|
40
|
Rowley MJ, Lyu X, Rana V, Ando-Kuri M, Karns R, Bosco G, Corces VG. Condensin II Counteracts Cohesin and RNA Polymerase II in the Establishment of 3D Chromatin Organization. Cell Rep 2019; 26:2890-2903.e3. [PMID: 30865881 PMCID: PMC6424357 DOI: 10.1016/j.celrep.2019.01.116] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 01/02/2019] [Accepted: 01/30/2019] [Indexed: 12/22/2022] Open
Abstract
Interaction domains in Drosophila chromosomes form by segregation of active and inactive chromatin in the absence of CTCF loops, but the role of transcription versus other architectural proteins in chromatin organization is unclear. Here, we find that positioning of RNAPII via transcription elongation is essential in the formation of gene loops, which in turn interact to form compartmental domains. Inhibition of transcription elongation or depletion of cohesin decreases gene looping and formation of active compartmental domains. In contrast, depletion of condensin II, which also localizes to active chromatin, causes increased gene looping, formation of compartmental domains, and stronger intra-chromosomal compartmental interactions. Condensin II has a similar role in maintaining inter-chromosomal interactions responsible for pairing between homologous chromosomes, whereas inhibition of transcription elongation or cohesin depletion has little effect on homolog pairing. The results suggest distinct roles for cohesin and condensin II in the establishment of 3D nuclear organization in Drosophila.
Collapse
Affiliation(s)
- M Jordan Rowley
- Department of Biology, Emory University, 1510 Clifton Road NE, Atlanta, GA 30322, USA
| | - Xiaowen Lyu
- Department of Biology, Emory University, 1510 Clifton Road NE, Atlanta, GA 30322, USA
| | - Vibhuti Rana
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Masami Ando-Kuri
- Department of Biology, Emory University, 1510 Clifton Road NE, Atlanta, GA 30322, USA
| | - Rachael Karns
- Department of Biology, Emory University, 1510 Clifton Road NE, Atlanta, GA 30322, USA
| | - Giovanni Bosco
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Victor G Corces
- Department of Biology, Emory University, 1510 Clifton Road NE, Atlanta, GA 30322, USA.
| |
Collapse
|
41
|
RNA Stabilizes Transcription-Dependent Chromatin Loops Induced By Nuclear Hormones. Sci Rep 2019; 9:3925. [PMID: 30850627 PMCID: PMC6408484 DOI: 10.1038/s41598-019-40123-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 02/08/2019] [Indexed: 01/14/2023] Open
Abstract
We show that transcription induced by nuclear receptors for estrogen (E2) or retinoic acid (RA) is associated with formation of chromatin loops that juxtapose the 5’ end (containing the promoter) with the enhancer and the 3′ polyA addition site of the target gene. We find three loop configurations which change as a function of time after induction: 1. RA or E2-induced loops which connect the 5′ end, the enhancer and the 3′ end of the gene, and are stabilized by RNA early after induction; 2. E2-independent loops whose stability does not require RNA; 3. Loops detected only by treatment of chromatin with RNAse H1 prior to hormonal induction. RNAse H1 digests RNA that occludes the relevant restriction sites, thus preventing detection of these loops. R-loops at the 5′ and 3′ ends of the RA or E2-target genes were demonstrated by immunoprecipitation with anti-DNA-RNA hybrid antibodies as well as by sensitivity to RNAse H1. The cohesin RAD21 subunit is preferentially recruited to the target sites upon RA or E2 induction of transcription. RAD21 binding to chromatin is eliminated by RNAse H1. We identified E2-induced and RNase H1-sensitive antisense RNAs located at the 5′ and 3′ ends of the E2-induced transcription unit which stabilize the loops and RAD21 binding to chromatin. This is the first report of chromatin loops that form after gene induction that are maintained by RNA:DNA hybrids.
Collapse
|
42
|
Ohno M, Ando T, Priest DG, Kumar V, Yoshida Y, Taniguchi Y. Sub-nucleosomal Genome Structure Reveals Distinct Nucleosome Folding Motifs. Cell 2019; 176:520-534.e25. [DOI: 10.1016/j.cell.2018.12.014] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 10/16/2018] [Accepted: 12/09/2018] [Indexed: 12/11/2022]
|
43
|
Gu C, Liu S, Wu Q, Zhang L, Guo F. Integrative single-cell analysis of transcriptome, DNA methylome and chromatin accessibility in mouse oocytes. Cell Res 2018; 29:110-123. [PMID: 30560925 PMCID: PMC6355938 DOI: 10.1038/s41422-018-0125-4] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 11/22/2018] [Indexed: 11/09/2022] Open
Abstract
Oocyte growth is a key step in forming mature eggs that are ready to be fertilized. The states and modifications of chromatin represent critical sources of information for this process. However, the dynamics and interrelations of these chromatin characteristics remain elusive. In this study, we developed an improved scCOOL-seq technique (iscCOOL-seq), which is a multi-omics, single-cell and single-base resolution method with high mapping rates, and explored the chromatin accessibility landscape and its relationship to DNA methylation in growing mouse oocytes. The most dramatic change in chromatin accessibility occurs during oocyte growth initiation, accompanied with prominent transcriptome alterations and an elevated variation in DNA methylation levels among individual oocytes. Unlike CpG islands (CGIs), partially methylated domains (PMDs) are associated with a low density of nucleosome-depleted regions (NDRs) during the whole maturation period. Surprisingly, highly expressed genes are usually associated with NDRs at their transcriptional end sites (TESs). In addition, genes with de novo methylated gene bodies during oocyte maturation are already open at their promoters before oocyte growth initiation. Furthermore, epigenetic and transcription factors that might be involved in oocyte maturation are identified. Our work paves the way for dissecting the complex, yet highly coordinated, epigenetic alterations during mouse oocyte growth and the establishment of totipotency.
Collapse
Affiliation(s)
- Chan Gu
- Center for Translational Medicine, Ministry of Education Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Shanling Liu
- Center for Translational Medicine, Ministry of Education Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Qihong Wu
- Center for Translational Medicine, Ministry of Education Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Lin Zhang
- Center for Translational Medicine, Ministry of Education Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Fan Guo
- Center for Translational Medicine, Ministry of Education Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, 610041, China. .,Ministry of Education Key Laboratory of Bio-resource and Eco-environment, College of Life Sciences, Sichuan University, Chengdu, Sichuan, 610041, China.
| |
Collapse
|
44
|
Juárez-Reyes A, Castaño I. Chromatin architecture and virulence-related gene expression in eukaryotic microbial pathogens. Curr Genet 2018; 65:435-443. [PMID: 30443783 DOI: 10.1007/s00294-018-0903-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 10/30/2018] [Accepted: 11/10/2018] [Indexed: 12/19/2022]
Abstract
A fundamental question in biology is to understand how appropriate transcriptional regulation and dense packaging of the genetic material within the eukaryotic nucleus are achieved. The exquisite gene expression control and other metabolic processes of DNA require a highly complex, multilayered, three-dimensional architecture of the chromatin and its specific compartmentalization within the nucleus. Some of these architectural and sub-nuclear positioning mechanisms have been extensively co-opted by eukaryotic pathogens to keep fine expression control and expansion of virulence-related gene families in Plasmodium falciparum, Trypanosoma brucei and Candida glabrata. For example non-linear interactions between distant cis-acting regions and the formation of chromatin loops are required for appropriate regulation of the expression of virulence-related multi-gene families encoding cell surface proteins. These gene families are located near the chromosome ends and tethered to the nuclear periphery. Consequently, only one or very few genes of the family are expressed at a time. These genes are involved in antigenic variation in parasites and the generation of subpopulations of cells with diverse antigenic proteins at the surface in some pathogenic fungi, making them highly efficient pathogens.
Collapse
Affiliation(s)
- Alejandro Juárez-Reyes
- División de Biología Molecular, IPICYT, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, 78216, San Luis Potosí, SLP, Mexico
| | - Irene Castaño
- División de Biología Molecular, IPICYT, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, 78216, San Luis Potosí, SLP, Mexico.
| |
Collapse
|
45
|
Szalaj P, Plewczynski D. Three-dimensional organization and dynamics of the genome. Cell Biol Toxicol 2018; 34:381-404. [PMID: 29568981 PMCID: PMC6133016 DOI: 10.1007/s10565-018-9428-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/11/2018] [Indexed: 12/30/2022]
Abstract
Genome is a complex hierarchical structure, and its spatial organization plays an important role in its function. Chromatin loops and topological domains form the basic structural units of this multiscale organization and are essential to orchestrate complex regulatory networks and transcription mechanisms. They also form higher-order structures such as chromosomal compartments and chromosome territories. Each level of this intrinsic architecture is governed by principles and mechanisms that we only start to understand. In this review, we summarize the current view of the genome architecture on the scales ranging from chromatin loops to the whole genome. We describe cell-to-cell variability, links between genome reorganization and various genomic processes, such as chromosome X inactivation and cell differentiation, and the interplay between different experimental techniques.
Collapse
Affiliation(s)
- Przemyslaw Szalaj
- Centre for Innovative Research, Medical University of Bialystok, Białystok, Poland.
- I-BioStat, Hasselt University, Hasselt, Belgium.
- Centre of New Technologies, University of Warsaw, Warsaw, Poland.
| | - Dariusz Plewczynski
- Centre for Innovative Research, Medical University of Bialystok, Białystok, Poland
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Faculty of Mathematics and Information Science, Warsaw University of Technology, Warsaw, Poland
| |
Collapse
|
46
|
Werner MS, Sieriebriennikov B, Prabh N, Loschko T, Lanz C, Sommer RJ. Young genes have distinct gene structure, epigenetic profiles, and transcriptional regulation. Genome Res 2018; 28:1675-1687. [PMID: 30232198 PMCID: PMC6211652 DOI: 10.1101/gr.234872.118] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 09/05/2018] [Indexed: 12/22/2022]
Abstract
Species-specific, new, or "orphan" genes account for 10%-30% of eukaryotic genomes. Although initially considered to have limited function, an increasing number of orphan genes have been shown to provide important phenotypic innovation. How new genes acquire regulatory sequences for proper temporal and spatial expression is unknown. Orphan gene regulation may rely in part on origination in open chromatin adjacent to preexisting promoters, although this has not yet been assessed by genome-wide analysis of chromatin states. Here, we combine taxon-rich nematode phylogenies with Iso-Seq, RNA-seq, ChIP-seq, and ATAC-seq to identify the gene structure and epigenetic signature of orphan genes in the satellite model nematode Pristionchus pacificus Consistent with previous findings, we find young genes are shorter, contain fewer exons, and are on average less strongly expressed than older genes. However, the subset of orphan genes that are expressed exhibit distinct chromatin states from similarly expressed conserved genes. Orphan gene transcription is determined by a lack of repressive histone modifications, confirming long-held hypotheses that open chromatin is important for new gene formation. Yet orphan gene start sites more closely resemble enhancers defined by H3K4me1, H3K27ac, and ATAC-seq peaks, in contrast to conserved genes that exhibit traditional promoters defined by H3K4me3 and H3K27ac. Although the majority of orphan genes are located on chromosome arms that contain high recombination rates and repressive histone marks, strongly expressed orphan genes are more randomly distributed. Our results support a model of new gene origination by rare integration into open chromatin near enhancers.
Collapse
Affiliation(s)
- Michael S Werner
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Bogdan Sieriebriennikov
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Neel Prabh
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Tobias Loschko
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Christa Lanz
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Ralf J Sommer
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| |
Collapse
|
47
|
Catabolic repression in early-diverging anaerobic fungi is partially mediated by natural antisense transcripts. Fungal Genet Biol 2018; 121:1-9. [PMID: 30223087 DOI: 10.1016/j.fgb.2018.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/10/2018] [Accepted: 09/11/2018] [Indexed: 12/16/2022]
Abstract
Early-diverging anaerobic fungi (order: Neocallimastigomycota), lignocelluolytic chytrid-like fungi central to fiber degradation in the digestive tracts of large herbivores, are attractive sources of cellulases and hemicellulases for biotechnology. Enzyme expression is tightly regulated and coordinated through mechanisms that remain unelucidated to optimize hydrolytic efficiency. Our analysis of anaerobic fungal transcriptomes reveals hundreds of cis-natural antisense transcripts (cis-NATs), which we hypothesize play an integral role in this regulation. Through integrated genomic and transcriptomic sequencing on a range of catabolic substrates, we validate these NATs in three species (Anaeromyces robustus, Neocallimasix californiae, and Piromyces finnis), and analyze their expression patterns and prevalence to gain insight into their function. NAT function was diverse and conserved across the three fungal genomes studied, with 10% of all metabolic process NATs associated with lignocellulose hydrolysis. Despite these similarities, however, only eleven gene targets were conserved orthologs. Several NATs were dynamically regulated by lignocellulosic substrates while their gene targets were unregulated. This observation is consistent with a hypothesized, but untested, regulatory mechanism where selected genes are exclusively regulated at the transcriptional/post-transcriptional level by NATs. However, only genes with high NAT relative expression levels displayed this phenomenon, suggesting a selection mechanism that favors larger dynamic ranges for more precise control of gene expression. In addition to this mode, we observed two other possible regulatory fates: canonical transcriptional regulation with no NAT response, and positive co-regulation of target mRNA and cognate NAT, which we hypothesize is a fine-tuning strategy to locally negate control outputs from global regulators. Our work reveals the complex contributions of antisense RNA to the catabolic response in anaerobic fungi, highlighting its importance in understanding lignocellulolytic activity for bioenergy applications. More importantly, the relative expression of NAT to target may form a critical determinant of transcriptional vs post-transcriptional (NAT) control of gene expression in primitive anaerobic fungi.
Collapse
|
48
|
D'Ippolito AM, McDowell IC, Barrera A, Hong LK, Leichter SM, Bartelt LC, Vockley CM, Majoros WH, Safi A, Song L, Gersbach CA, Crawford GE, Reddy TE. Pre-established Chromatin Interactions Mediate the Genomic Response to Glucocorticoids. Cell Syst 2018; 7:146-160.e7. [PMID: 30031775 DOI: 10.1016/j.cels.2018.06.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 02/27/2018] [Accepted: 06/12/2018] [Indexed: 10/28/2022]
Abstract
The glucocorticoid receptor (GR) is a hormone-inducible transcription factor involved in metabolic and anti-inflammatory gene expression responses. To investigate what controls interactions between GR binding sites and their target genes, we used in situ Hi-C to generate high-resolution, genome-wide maps of chromatin interactions before and after glucocorticoid treatment. We found that GR binding to the genome typically does not cause new chromatin interactions to target genes but instead acts through chromatin interactions that already exist prior to hormone treatment. Both glucocorticoid-induced and glucocorticoid-repressed genes increased interactions with distal GR binding sites. In addition, while glucocorticoid-induced genes increased interactions with transcriptionally active chromosome compartments, glucocorticoid-repressed genes increased interactions with transcriptionally silent compartments. Lastly, while the architectural DNA-binding proteins CTCF and RAD21 were bound to most chromatin interactions, we found that glucocorticoid-responsive chromatin interactions were depleted for CTCF binding but enriched for RAD21. Together, these findings offer new insights into the mechanisms underlying GC-mediated gene activation and repression.
Collapse
Affiliation(s)
- Anthony M D'Ippolito
- University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA; Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA
| | - Ian C McDowell
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Computational Biology and Bioinformatics Graduate Program, Duke University, Durham, NC 27708, USA
| | - Alejandro Barrera
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
| | - Linda K Hong
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA
| | - Sarah M Leichter
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA
| | - Luke C Bartelt
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA
| | - Christopher M Vockley
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
| | - William H Majoros
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Computational Biology and Bioinformatics Graduate Program, Duke University, Durham, NC 27708, USA
| | - Alexias Safi
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA
| | - Lingyun Song
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA
| | - Charles A Gersbach
- University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA; Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; Department of Orthopedic Surgery, Duke University Medical Center, Durham, NC 27708, USA
| | - Gregory E Crawford
- University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA; Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA; Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Timothy E Reddy
- University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA; Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Computational Biology and Bioinformatics Graduate Program, Duke University, Durham, NC 27708, USA; Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
| |
Collapse
|
49
|
Guo L, Cao X, Liu Y, Li J, Li Y, Li D, Zhang K, Gao C, Dong A, Liu X. A chromatin loop represses WUSCHEL expression in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 94:1083-1097. [PMID: 29660180 DOI: 10.1111/tpj.13921] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/20/2018] [Accepted: 03/22/2018] [Indexed: 05/27/2023]
Abstract
WUSCHEL (WUS) is critical for plant meristem maintenance and determinacy in Arabidopsis, and the regulation of its spatiotemporal expression patterns is complex. We previously found that AGAMOUS (AG), a key MADS-domain transcription factor in floral organ identity and floral meristem determinacy, can directly suppress WUS expression through the recruitment of the Polycomb group (PcG) protein TERMINAL FLOWER 2 (TFL2, also known as LIKE HETEROCHROMATIN PROTEIN 1, LHP1) at the WUS locus; however, the mechanism by which WUS is repressed remains unclear. Here, using chromosome conformation capture (3C) and chromatin immunoprecipitation 3C, we found that two specific regions flanking the WUS gene body bound by AG and TFL2 form a chromatin loop that is directly promoted by AG during flower development in a manner independent of the physical distance and sequence content of the intervening region. Moreover, AG physically interacts with TFL2, and TFL2 binding to the chromatin loop is dependent on AG. Transgenic and CRISPR/Cas9-edited lines showed that the WUS chromatin loop represses gene expression by blocking the recruitment of RNA polymerase II at the locus. The findings uncover the WUS chromatin loop as another regulatory mechanism controlling WUS expression, and also shed light on the factors required for chromatin conformation change and their recruitment.
Collapse
Affiliation(s)
- Lin Guo
- State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China
- Hebei Collaboration Innovation Center for Cell Signaling, Shijiazhuang, 050021, China
| | - Xiuwei Cao
- State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China
- Hebei Collaboration Innovation Center for Cell Signaling, Shijiazhuang, 050021, China
| | - Yuhao Liu
- State Key Laboratory of Genetic Engineering, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Collaborative Innovation Center for Genetics and Development, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, 200433, China
| | - Jun Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yongpeng Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China
- Hebei Collaboration Innovation Center for Cell Signaling, Shijiazhuang, 050021, China
| | - Dongming Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China
- Hebei Collaboration Innovation Center for Cell Signaling, Shijiazhuang, 050021, China
| | - Ke Zhang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China
- Hebei Collaboration Innovation Center for Cell Signaling, Shijiazhuang, 050021, China
| | - Caixia Gao
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Aiwu Dong
- State Key Laboratory of Genetic Engineering, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Collaborative Innovation Center for Genetics and Development, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, 200433, China
| | - Xigang Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China
- Hebei Collaboration Innovation Center for Cell Signaling, Shijiazhuang, 050021, China
| |
Collapse
|
50
|
Yu D, Ma X, Zuo Z, Wang H, Meng Y. Classification of Transcription Boundary-Associated RNAs (TBARs) in Animals and Plants. Front Genet 2018; 9:168. [PMID: 29868116 PMCID: PMC5960741 DOI: 10.3389/fgene.2018.00168] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/26/2018] [Indexed: 11/13/2022] Open
Abstract
There is increasing evidence suggesting the contribution of non-coding RNAs (ncRNAs) to the phenotypic and physiological complexity of organisms. A novel ncRNA species has been identified near the transcription boundaries of protein-coding genes in eukaryotes, bacteria, and archaea. This review provides a detailed description of these transcription boundary-associated RNAs (TBARs), including their classification. Based on their genomic distribution, TBARs are divided into two major groups: promoter-associated RNAs (PARs) and terminus-associated RNAs (TARs). Depending on the sequence length, each group is further classified into long RNA species (>200 nt) and small RNA species (<200 nt). According to these rules of TBAR classification, divergent ncRNAs with confusing nomenclatures, such as promoter upstream transcripts (PROMPTs), upstream antisense RNAs (uaRNAs), stable unannotated transcripts (SUTs), cryptic unstable transcripts (CUTs), upstream non-coding transcripts (UNTs), transcription start site-associated RNAs (TSSaRNAs), transcription initiation RNAs (tiRNAs), and transcription termination site-associated RNAs (TTSaRNAs), were assigned to specific classes. Although the biogenesis pathways of PARs and TARs have not yet been clearly elucidated, previous studies indicate that some of the PARs have originated either through divergent transcription or via RNA polymerase pausing. Intriguing findings regarding the functional implications of the TBARs such as the long-range “gene looping” model, which explains their role in the transcriptional regulation of protein-coding genes, are also discussed. Altogether, this review provides a comprehensive overview of the current research status of TBARs, which will promote further investigations in this research area.
Collapse
Affiliation(s)
- Dongliang Yu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Xiaoxia Ma
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Ziwei Zuo
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Huizhong Wang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Yijun Meng
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| |
Collapse
|