51
|
Ash2l, an obligatory component of H3K4 methylation complexes, regulates neural crest development. Dev Biol 2022; 492:14-24. [PMID: 36162552 DOI: 10.1016/j.ydbio.2022.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 08/29/2022] [Accepted: 09/20/2022] [Indexed: 02/05/2023]
Abstract
The vertebrate nervous system develops from embryonic neural plate and neural crest. Although genetic mechanisms governing vertebrate neural development have been investigated in depth, epigenetic regulation of this process remains less understood. Redundancy of epigenetic factors and early lethality of animals deficient in critical epigenetic components pose major challenges in characterization of epigenetic factors in vertebrate neural development. In this study, we use the amphibian model Xenopus laevis to investigate the roles of non-redundant, obligatory components of all histone H3K4 activating methylation complexes (COMPASS, also known as SET1/MLL complexes) in early neural development. The two genes that we focus on, Ash2l and Dpy30, regulate mesendodermal differentiation in mouse embryonic stem cells and cause early embryonic lethality when removed from mouse embryos. Using targeted knockdown of the genes in dorsal ectoderm of Xenopus that gives rise to future nervous system, we show here that ash2l and dpy30 are required for neural and neural crest marker expression in Xenopus late neurula embryos but are dispensable for early neural and neural plate border gene expression. Co-immunoprecipitation assays reveal that Dpy30 and Ash2L associate with the neural plate border transcription factors, such as Msx1 and Tfap2a. Chromatin immunoprecipitation (ChIP) assay further demonstrates that Ash2L and the H3K4me3 active histone mark accumulate at the promoter regions of the neural crest gene sox10 in a Tfap2a-dependent manner. Collectively, our data suggest that Ash2l and Dpy30 interact with specific transcription factors to recruit COMPASS complexes to the regulatory regions of neural crest specification genes to control their expression and influence development of the nervous system during vertebrate embryogenesis.
Collapse
|
52
|
Diacou R, Nandigrami P, Fiser A, Liu W, Ashery-Padan R, Cvekl A. Cell fate decisions, transcription factors and signaling during early retinal development. Prog Retin Eye Res 2022; 91:101093. [PMID: 35817658 PMCID: PMC9669153 DOI: 10.1016/j.preteyeres.2022.101093] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 12/30/2022]
Abstract
The development of the vertebrate eyes is a complex process starting from anterior-posterior and dorso-ventral patterning of the anterior neural tube, resulting in the formation of the eye field. Symmetrical separation of the eye field at the anterior neural plate is followed by two symmetrical evaginations to generate a pair of optic vesicles. Next, reciprocal invagination of the optic vesicles with surface ectoderm-derived lens placodes generates double-layered optic cups. The inner and outer layers of the optic cups develop into the neural retina and retinal pigment epithelium (RPE), respectively. In vitro produced retinal tissues, called retinal organoids, are formed from human pluripotent stem cells, mimicking major steps of retinal differentiation in vivo. This review article summarizes recent progress in our understanding of early eye development, focusing on the formation the eye field, optic vesicles, and early optic cups. Recent single-cell transcriptomic studies are integrated with classical in vivo genetic and functional studies to uncover a range of cellular mechanisms underlying early eye development. The functions of signal transduction pathways and lineage-specific DNA-binding transcription factors are dissected to explain cell-specific regulatory mechanisms underlying cell fate determination during early eye development. The functions of homeodomain (HD) transcription factors Otx2, Pax6, Lhx2, Six3 and Six6, which are required for early eye development, are discussed in detail. Comprehensive understanding of the mechanisms of early eye development provides insight into the molecular and cellular basis of developmental ocular anomalies, such as optic cup coloboma. Lastly, modeling human development and inherited retinal diseases using stem cell-derived retinal organoids generates opportunities to discover novel therapies for retinal diseases.
Collapse
Affiliation(s)
- Raven Diacou
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Prithviraj Nandigrami
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Andras Fiser
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Wei Liu
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Ruth Ashery-Padan
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Ales Cvekl
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
| |
Collapse
|
53
|
Hansen JL, Cohen BA. A quantitative metric of pioneer activity reveals that HNF4A has stronger in vivo pioneer activity than FOXA1. Genome Biol 2022; 23:221. [PMID: 36253868 PMCID: PMC9575205 DOI: 10.1186/s13059-022-02792-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 10/11/2022] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND We and others have suggested that pioneer activity - a transcription factor's (TF's) ability to bind and open inaccessible loci - is not a qualitative trait limited to a select class of pioneer TFs. We hypothesize that most TFs display pioneering activity that depends on the TF concentration and the motif content at their target loci. RESULTS Here, we present a quantitative in vivo measure of pioneer activity that captures the relative difference in a TF's ability to bind accessible versus inaccessible DNA. The metric is based on experiments that use CUT&Tag to measure the binding of doxycycline-inducible TFs. For each location across the genome, we determine the concentration of doxycycline required for a TF to reach half-maximal occupancy; lower concentrations reflect higher affinity. We propose that the relative difference in a TF's affinity between ATAC-seq labeled accessible and inaccessible binding sites is a measure of its pioneer activity. We estimate binding affinities at tens of thousands of genomic loci for the endodermal TFs FOXA1 and HNF4A and show that HNF4A has stronger pioneer activity than FOXA1. We show that both FOXA1 and HNF4A display higher binding affinity at inaccessible sites with more copies of their respective motifs. The quantitative analysis of binding suggests different modes of binding for FOXA1, including an anti-cooperative mode of binding at certain accessible loci. CONCLUSIONS Our results suggest that relative binding affinities are reasonable measures of pioneer activity and support the model wherein most TFs have some degree of context-dependent pioneer activity.
Collapse
Affiliation(s)
- Jeffrey L. Hansen
- The Edison Family Center for Genome Sciences and Systems Biology, School of Medicine, Washington University in St. Louis, Saint Louis, MO USA
- Department of Genetics, School of Medicine, Washington University in St. Louis, Saint Louis, MO USA
- Medical Scientist Training Program, Washington University in St. Louis, St. Louis, MO USA
| | - Barak A. Cohen
- The Edison Family Center for Genome Sciences and Systems Biology, School of Medicine, Washington University in St. Louis, Saint Louis, MO USA
- Department of Genetics, School of Medicine, Washington University in St. Louis, Saint Louis, MO USA
| |
Collapse
|
54
|
Beucher A, Miguel-Escalada I, Balboa D, De Vas MG, Maestro MA, Garcia-Hurtado J, Bernal A, Gonzalez-Franco R, Vargiu P, Heyn H, Ravassard P, Ortega S, Ferrer J. The HASTER lncRNA promoter is a cis-acting transcriptional stabilizer of HNF1A. Nat Cell Biol 2022; 24:1528-1540. [PMID: 36202974 PMCID: PMC9586874 DOI: 10.1038/s41556-022-00996-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 08/16/2022] [Indexed: 11/08/2022]
Abstract
The biological purpose of long non-coding RNAs (lncRNAs) is poorly understood. Haploinsufficient mutations in HNF1A homeobox A (HNF1A), encoding a homeodomain transcription factor, cause diabetes mellitus. Here, we examine HASTER, the promoter of an lncRNA antisense to HNF1A. Using mouse and human models, we show that HASTER maintains cell-specific physiological HNF1A concentrations through positive and negative feedback loops. Pancreatic β cells from Haster mutant mice consequently showed variegated HNF1A silencing or overexpression, resulting in hyperglycaemia. HASTER-dependent negative feedback was essential to prevent HNF1A binding to inappropriate genomic regions. We demonstrate that the HASTER promoter DNA, rather than the lncRNA, modulates HNF1A promoter-enhancer interactions in cis and thereby regulates HNF1A transcription. Our studies expose a cis-regulatory element that is unlike classic enhancers or silencers, it stabilizes the transcription of its target gene and ensures the fidelity of a cell-specific transcription factor program. They also show that disruption of a mammalian lncRNA promoter can cause diabetes mellitus.
Collapse
Affiliation(s)
- Anthony Beucher
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain.
| | - Irene Miguel-Escalada
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Madrid, Spain
| | - Diego Balboa
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Madrid, Spain
| | - Matías G De Vas
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Miguel Angel Maestro
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Madrid, Spain
| | - Javier Garcia-Hurtado
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Madrid, Spain
| | - Aina Bernal
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Madrid, Spain
| | - Roser Gonzalez-Franco
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | | | - Holger Heyn
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- CNAG-CRG, Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
| | - Philippe Ravassard
- Biotechnology and Biotherapy Team, Institut du Cerveau et de la Moelle, CNRS UMR7225, INSERM U975, University Pierre et Marie Curie, Paris, France
| | - Sagrario Ortega
- Transgenics Unit, Spanish National Cancer Research Centre, Madrid, Spain
| | - Jorge Ferrer
- Section of Genetics and Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Madrid, Spain.
| |
Collapse
|
55
|
Kaplun DS, Kaluzhny DN, Prokhortchouk EB, Zhenilo SV. DNA Methylation: Genomewide Distribution, Regulatory Mechanism and Therapy Target. Acta Naturae 2022; 14:4-19. [PMID: 36694897 PMCID: PMC9844086 DOI: 10.32607/actanaturae.11822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 11/29/2022] [Indexed: 01/22/2023] Open
Abstract
DNA methylation is the most important epigenetic modification involved in the regulation of transcription, imprinting, establishment of X-inactivation, and the formation of a chromatin structure. DNA methylation in the genome is often associated with transcriptional repression and the formation of closed heterochromatin. However, the results of genome-wide studies of the DNA methylation pattern and transcriptional activity of genes have nudged us toward reconsidering this paradigm, since the promoters of many genes remain active despite their methylation. The differences in the DNA methylation distribution in normal and pathological conditions allow us to consider methylation as a diagnostic marker or a therapy target. In this regard, the need to investigate the factors affecting DNA methylation and those involved in its interpretation becomes pressing. Recently, a large number of protein factors have been uncovered, whose ability to bind to DNA depends on their methylation. Many of these proteins act not only as transcriptional activators or repressors, but also affect the level of DNA methylation. These factors are considered potential therapeutic targets for the treatment of diseases resulting from either a change in DNA methylation or a change in the interpretation of its methylation level. In addition to protein factors, a secondary DNA structure can also affect its methylation and can be considered as a therapy target. In this review, the latest research into the DNA methylation landscape in the genome has been summarized to discuss why some DNA regions avoid methylation and what factors can affect its level or interpretation and, therefore, can be considered a therapy target.
Collapse
Affiliation(s)
- D. S. Kaplun
- Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071 Russia
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119071 Russia
| | - D. N. Kaluzhny
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991 Russia
| | - E. B. Prokhortchouk
- Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071 Russia
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119071 Russia
| | - S. V. Zhenilo
- Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071 Russia
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119071 Russia
| |
Collapse
|
56
|
Lin JM, Mitchell TA, Rothstein M, Pehl A, Taroc EZM, Katreddi RR, Parra KE, Zuloaga DG, Simoes-Costa M, Forni PE. Sociosexual behavior requires both activating and repressive roles of Tfap2e/AP-2ε in vomeronasal sensory neurons. eLife 2022; 11:e77259. [PMID: 36111787 PMCID: PMC9525060 DOI: 10.7554/elife.77259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 09/15/2022] [Indexed: 11/16/2022] Open
Abstract
Neuronal identity dictates the position in an epithelium, and the ability to detect, process, and transmit specific signals to specified targets. Transcription factors (TFs) determine cellular identity via direct modulation of genetic transcription and recruiting chromatin modifiers. However, our understanding of the mechanisms that define neuronal identity and their magnitude remain a critical barrier to elucidate the etiology of congenital and neurodegenerative disorders. The rodent vomeronasal organ provides a unique system to examine in detail the molecular mechanisms underlying the differentiation and maturation of chemosensory neurons. Here, we demonstrated that the identity of postmitotic/maturing vomeronasal sensory neurons (VSNs), and vomeronasal-dependent behaviors can be reprogrammed through the rescue of Tfap2e/AP-2ε expression in the Tfap2eNull mice, and partially reprogrammed by inducing ectopic Tfap2e expression in mature apical VSNs. We suggest that the TF Tfap2e can reprogram VSNs bypassing cellular plasticity restrictions, and that it directly controls the expression of batteries of vomeronasal genes.
Collapse
Affiliation(s)
- Jennifer M Lin
- Department of Biological Sciences, University at Albany, State University of New YorkAlbanyUnited States
- The RNA Institute, University at AlbanyAlbanyUnited States
| | - Tyler A Mitchell
- Department of Biological Sciences, University at Albany, State University of New YorkAlbanyUnited States
- The RNA Institute, University at AlbanyAlbanyUnited States
| | - Megan Rothstein
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Alison Pehl
- Department of Biological Sciences, University at Albany, State University of New YorkAlbanyUnited States
- The RNA Institute, University at AlbanyAlbanyUnited States
| | - Ed Zandro M Taroc
- Department of Biological Sciences, University at Albany, State University of New YorkAlbanyUnited States
- The RNA Institute, University at AlbanyAlbanyUnited States
| | - Raghu R Katreddi
- Department of Biological Sciences, University at Albany, State University of New YorkAlbanyUnited States
- The RNA Institute, University at AlbanyAlbanyUnited States
| | - Katherine E Parra
- Department of Psychology, University at Albany, State University of New YorkAlbanyUnited States
| | - Damian G Zuloaga
- Department of Psychology, University at Albany, State University of New YorkAlbanyUnited States
| | - Marcos Simoes-Costa
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Paolo Emanuele Forni
- Department of Biological Sciences, University at Albany, State University of New YorkAlbanyUnited States
- The RNA Institute, University at AlbanyAlbanyUnited States
| |
Collapse
|
57
|
Partitioned usage of chromatin remodelers by nucleosome-displacing factors. Cell Rep 2022; 40:111250. [PMID: 36001970 PMCID: PMC9422437 DOI: 10.1016/j.celrep.2022.111250] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/29/2022] [Accepted: 08/01/2022] [Indexed: 11/22/2022] Open
Abstract
Nucleosome-displacing-factors (NDFs) in yeast, similar to pioneer factors in higher eukaryotes, can open closed chromatin and generate nucleosome-depleted regions (NDRs). NDRs in yeast are also affected by ATP-dependent chromatin remodelers (CRs). However, how NDFs and CRs coordinate in nucleosome invasion and NDR formation is still unclear. Here, we design a high-throughput method to systematically study the interplay between NDFs and CRs. By combining an integrated synthetic oligonucleotide library with DNA methyltransferase-based, single-molecule nucleosome mapping, we measure the impact of CRs on NDRs generated by individual NDFs. We find that CRs are dispensable for nucleosome invasion by NDFs, and they function downstream of NDF binding to modulate the NDR length. A few CRs show high specificity toward certain NDFs; however, in most cases, CRs are recruited in a factor-nonspecific and NDR length-dependent manner. Overall, our study provides a framework to investigate how NDFs and CRs cooperate to regulate chromatin opening. Chromatin accessibility in yeast is regulated by nucleosome-displacing-factors (NDFs) and chromatin remodelers (CRs). Chen et al. show that NDFs first invade into nucleosomes and then recruit CRs to modulate the NDR length. NDF-specific and NDR length-dependent recruitment of CRs allow partitioned usage of CRs by NDFs.
Collapse
|
58
|
Luzete-Monteiro E, Zaret KS. Structures and consequences of pioneer factor binding to nucleosomes. Curr Opin Struct Biol 2022; 75:102425. [PMID: 35863165 PMCID: PMC9976633 DOI: 10.1016/j.sbi.2022.102425] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/10/2022] [Accepted: 06/16/2022] [Indexed: 11/15/2022]
Abstract
Pioneer transcription factors are able to bind a partially exposed motif on the surface of a nucleosome, enabling the proteins to target sites in silent regions of chromatin that have been compacted by linker histone. The targeting of nucleosomal DNA by pioneer factors has been observed in vitro and in vivo, where binding can promote local nucleosome exposure that allows other transcription factors, nucleosome remodelers, and histone modifiers to engage the chromatin and elicit gene activation or further repression. Pioneer factors thereby establish new gene expression programs during cell fate changes that occur during embryonic development, regeneration, and cancer. Here, we review recent biophysical studies that reveal the structural features and strategies used by pioneer factors to accomplish nucleosome binding and the consequential changes to nucleosomes that can lead to DNA accessibility.
Collapse
Affiliation(s)
- Edgar Luzete-Monteiro
- Institute for Regenerative Medicine, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, 9-131 SCTR, 3400 Civic Center Blvd., Philadelphia, PA 19104-5157, USA.,Department of Biology, School of Arts and Sciences, University of Pennsylvania, 433 S University Ave, Philadelphia, PA 19104-4544
| | - Kenneth S. Zaret
- Institute for Regenerative Medicine, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, 9-131 SCTR, 3400 Civic Center Blvd., Philadelphia, PA 19104-5157, USA
| |
Collapse
|
59
|
Gregoricchio S, Polit L, Esposito M, Berthelet J, Delestré L, Evanno E, Diop M, Gallais I, Aleth H, Poplineau M, Zwart W, Rosenbauer F, Rodrigues-Lima F, Duprez E, Boeva V, Guillouf C. HDAC1 and PRC2 mediate combinatorial control in SPI1/PU.1-dependent gene repression in murine erythroleukaemia. Nucleic Acids Res 2022; 50:7938-7958. [PMID: 35871293 PMCID: PMC9371914 DOI: 10.1093/nar/gkac613] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/18/2022] [Accepted: 06/30/2022] [Indexed: 11/23/2022] Open
Abstract
Although originally described as transcriptional activator, SPI1/PU.1, a major player in haematopoiesis whose alterations are associated with haematological malignancies, has the ability to repress transcription. Here, we investigated the mechanisms underlying gene repression in the erythroid lineage, in which SPI1 exerts an oncogenic function by blocking differentiation. We show that SPI1 represses genes by binding active enhancers that are located in intergenic or gene body regions. HDAC1 acts as a cooperative mediator of SPI1-induced transcriptional repression by deacetylating SPI1-bound enhancers in a subset of genes, including those involved in erythroid differentiation. Enhancer deacetylation impacts on promoter acetylation, chromatin accessibility and RNA pol II occupancy. In addition to the activities of HDAC1, polycomb repressive complex 2 (PRC2) reinforces gene repression by depositing H3K27me3 at promoter sequences when SPI1 is located at enhancer sequences. Moreover, our study identified a synergistic relationship between PRC2 and HDAC1 complexes in mediating the transcriptional repression activity of SPI1, ultimately inducing synergistic adverse effects on leukaemic cell survival. Our results highlight the importance of the mechanism underlying transcriptional repression in leukemic cells, involving complex functional connections between SPI1 and the epigenetic regulators PRC2 and HDAC1.
Collapse
Affiliation(s)
- Sebastian Gregoricchio
- Inserm U1170, Université Paris-Saclay, Gustave Roussy Cancer Campus , F- 94800 Villejuif, France
- Equipe Labellisée Ligue Nationale Contre le Cancer , France
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute , Amsterdam , The Netherlands
| | - Lélia Polit
- CNRS UMR8104, Inserm U1016, Université Paris Cité, Cochin Institute , F-75014 Paris , France
| | - Michela Esposito
- Inserm U1170, Université Paris-Saclay, Gustave Roussy Cancer Campus , F- 94800 Villejuif, France
- Equipe Labellisée Ligue Nationale Contre le Cancer , France
| | | | - Laure Delestré
- Inserm U1170, Université Paris-Saclay, Gustave Roussy Cancer Campus , F- 94800 Villejuif, France
- Equipe Labellisée Ligue Nationale Contre le Cancer , France
| | - Emilie Evanno
- Curie Institute , Inserm U830, F- 75005 Paris, France
| | - M’Boyba Diop
- Inserm U1170, Université Paris-Saclay, Gustave Roussy Cancer Campus , F- 94800 Villejuif, France
- Equipe Labellisée Ligue Nationale Contre le Cancer , France
| | | | - Hanna Aleth
- Institute of Molecular Tumor Biology, University of Münster , Münster, Germany
| | - Mathilde Poplineau
- CNRS UMR7258, Inserm U1068, Université Aix Marseille, Paoli-Calmettes Institute , CRCM, F-13009 Marseille , France
- Equipe Labellisée Ligue Nationale Contre le Cancer , France
| | - Wilbert Zwart
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute , Amsterdam , The Netherlands
| | - Frank Rosenbauer
- Institute of Molecular Tumor Biology, University of Münster , Münster, Germany
| | | | - Estelle Duprez
- CNRS UMR7258, Inserm U1068, Université Aix Marseille, Paoli-Calmettes Institute , CRCM, F-13009 Marseille , France
- Equipe Labellisée Ligue Nationale Contre le Cancer , France
| | - Valentina Boeva
- CNRS UMR8104, Inserm U1016, Université Paris Cité, Cochin Institute , F-75014 Paris , France
- Department of Computer Science and Department of Biology , ETH Zurich, 8092 Zurich , Switzerland
| | - Christel Guillouf
- Inserm U1170, Université Paris-Saclay, Gustave Roussy Cancer Campus , F- 94800 Villejuif, France
- Equipe Labellisée Ligue Nationale Contre le Cancer , France
| |
Collapse
|
60
|
Isbel L, Grand RS, Schübeler D. Generating specificity in genome regulation through transcription factor sensitivity to chromatin. Nat Rev Genet 2022; 23:728-740. [PMID: 35831531 DOI: 10.1038/s41576-022-00512-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2022] [Indexed: 12/11/2022]
Abstract
Cell type-specific gene expression relies on transcription factors (TFs) binding DNA sequence motifs embedded in chromatin. Understanding how motifs are accessed in chromatin is crucial to comprehend differential transcriptional responses and the phenotypic impact of sequence variation. Chromatin obstacles to TF binding range from DNA methylation to restriction of DNA access by nucleosomes depending on their position, composition and modification. In vivo and in vitro approaches now enable the study of TF binding in chromatin at unprecedented resolution. Emerging insights suggest that TFs vary in their ability to navigate chromatin states. However, it remains challenging to link binding and transcriptional outcomes to molecular characteristics of TFs or the local chromatin substrate. Here, we discuss our current understanding of how TFs access DNA in chromatin and novel techniques and directions towards a better understanding of this critical step in genome regulation.
Collapse
Affiliation(s)
- Luke Isbel
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Ralph S Grand
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Zentrum für Molekulare Biologie der Universität Heidelberg, Heidelberg, Germany
| | - Dirk Schübeler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland. .,Faculty of Sciences, University of Basel, Basel, Switzerland.
| |
Collapse
|
61
|
Allègre N, Chauveau S, Dennis C, Renaud Y, Meistermann D, Estrella LV, Pouchin P, Cohen-Tannoudji M, David L, Chazaud C. NANOG initiates epiblast fate through the coordination of pluripotency genes expression. Nat Commun 2022; 13:3550. [PMID: 35729116 PMCID: PMC9213552 DOI: 10.1038/s41467-022-30858-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 05/24/2022] [Indexed: 12/20/2022] Open
Abstract
The epiblast is the source of all mammalian embryonic tissues and of pluripotent embryonic stem cells. It differentiates alongside the primitive endoderm in a “salt and pepper” pattern from inner cell mass (ICM) progenitors during the preimplantation stages through the activity of NANOG, GATA6 and the FGF pathway. When and how epiblast lineage specification is initiated is still unclear. Here, we show that the coordinated expression of pluripotency markers defines epiblast identity. Conversely, ICM progenitor cells display random cell-to-cell variability in expression of various pluripotency markers, remarkably dissimilar from the epiblast signature and independently from NANOG, GATA6 and FGF activities. Coordination of pluripotency markers expression fails in Nanog and Gata6 double KO (DKO) embryos. Collectively, our data suggest that NANOG triggers epiblast specification by ensuring the coordinated expression of pluripotency markers in a subset of cells, implying a stochastic mechanism. These features are likely conserved, as suggested by analysis of human embryos. Pluripotent epiblast cells segregate from primitive endoderm in the blastocyst inner cell mass (ICM). Here the authors show that mosaic epiblast differentiation during mouse and human preimplantation development initiates stochastically in ICM progenitors, independently of the FGF pathway, and requires NANOG activity
Collapse
Affiliation(s)
- Nicolas Allègre
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Sabine Chauveau
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Cynthia Dennis
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Yoan Renaud
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France.,Byonet, 19 rue du courait, F-63200, Riom, France
| | - Dimitri Meistermann
- Université de Nantes, CHU Nantes, INSERM, CR2TI, UMR 1064, ITUN, F-44000, Nantes, France.,Université de Nantes, CNRS, LS2N, CNRS UMR 6004, F-44000, Nantes, France
| | - Lorena Valverde Estrella
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Pierre Pouchin
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France
| | - Michel Cohen-Tannoudji
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Epigenomics, Proliferation, and the Identity of Cells, Department of Developmental and Stem Cell Biology, F-75015, Paris, France
| | - Laurent David
- Université de Nantes, CHU Nantes, INSERM, CR2TI, UMR 1064, ITUN, F-44000, Nantes, France.,Université de Nantes, CHU Nantes, INSERM, CNRS, UMS Biocore, INSERM UMS 016, CNRS UMS 3556, F-44000, Nantes, France
| | - Claire Chazaud
- Université Clermont Auvergne, CNRS, INSERM, GReD Institute, Faculté de Médecine, F-63000, Clermont-Ferrand, France.
| |
Collapse
|
62
|
Dynamic nucleosome landscape elicits a noncanonical GATA2 pioneer model. Nat Commun 2022; 13:3145. [PMID: 35672415 PMCID: PMC9174260 DOI: 10.1038/s41467-022-30960-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 05/24/2022] [Indexed: 11/09/2022] Open
Abstract
Knowledge gaps remain on how nucleosome organization and dynamic reorganization are governed by specific pioneer factors in a genome-wide manner. In this study, we generate over three billons of multi-omics sequencing data to exploit dynamic nucleosome landscape governed by pioneer factors (PFs), FOXA1 and GATA2. We quantitatively define nine functional nucleosome states each with specific characteristic nucleosome footprints in LNCaP prostate cancer cells. Interestingly, we observe dynamic switches among nucleosome states upon androgen stimulation, accompanied by distinct differential (gained or lost) binding of FOXA1, GATA2, H1 as well as many other coregulators. Intriguingly, we reveal a noncanonical pioneer model of GATA2 that it initially functions as a PF binding at the edge of a nucleosome in an inaccessible crowding array. Upon androgen stimulation, GATA2 re-configures an inaccessible to accessible nucleosome state and subsequently acts as a master transcription factor either directly or recruits signaling specific transcription factors to enhance WNT signaling in an androgen receptor (AR)-independent manner. Our data elicit a pioneer and master dual role of GATA2 in mediating nucleosome dynamics and enhancing downstream signaling pathways. Our work offers structural and mechanistic insight into the dynamics of pioneer factors governing nucleosome reorganization.
Collapse
|
63
|
Heslop JA, Pournasr B, Duncan SA. Chromatin remodeling is restricted by transient GATA6 binding during iPSC differentiation to definitive endoderm. iScience 2022; 25:104300. [PMID: 35602939 PMCID: PMC9118154 DOI: 10.1016/j.isci.2022.104300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 03/22/2022] [Accepted: 04/21/2022] [Indexed: 11/06/2022] Open
Abstract
In addition to cooperatively driving transcriptional programs, emerging evidence supports transcription factors interacting with one another to modulate the outcome of binding events. As such, transcription factor interactions fine-tune the unique gene expression profiles required for developmental progression. Using human-induced pluripotent stem cells as a model of human endoderm lineage commitment, we reveal that GATA6 transiently co-localizes with EOMES at regions associated with non-endodermal lineages and is required for the repression of chromatin opening at these loci. Our results indicate that GATA6-dependent repression of chromatin remodeling, which is potentially mediated via the recruitment of NCOR1 to the EOMES interactome, contributes to definitive endoderm commitment. We anticipate that similar mechanisms are common during human development, furthering our understanding of the complex mechanisms that define cell fate decisions.
Collapse
Affiliation(s)
- James A. Heslop
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, USA
| | - Behshad Pournasr
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, USA
| | - Stephen A. Duncan
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, USA
| |
Collapse
|
64
|
ASC proneural factors are necessary for chromatin remodeling during neuroectodermal to neuroblast fate transition to ensure the timely initiation of the neural stem cell program. BMC Biol 2022; 20:107. [PMID: 35549704 PMCID: PMC9102361 DOI: 10.1186/s12915-022-01300-8] [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: 07/14/2021] [Accepted: 04/20/2022] [Indexed: 11/11/2022] Open
Abstract
Background In both Drosophila and mammals, the achaete-scute (ASC/ASCL) proneural bHLH transcription factors are expressed in the developing central and peripheral nervous systems, where they function during specification and maintenance of the neural stem cells in opposition to Notch signaling. In addition to their role in nervous system development, ASC transcription factors are oncogenic and exhibit chromatin reprogramming activity; however, the impact of ASC on chromatin dynamics during neural stem cell generation remains elusive. Here, we investigate the chromatin changes accompanying neural commitment using an integrative genetics and genomics methodology. Results We found that ASC factors bind equally strongly to two distinct classes of cis-regulatory elements: open regions remodeled earlier during maternal to zygotic transition by Zelda and less accessible, Zelda-independent regions. Both classes of cis-elements exhibit enhanced chromatin accessibility during neural specification and correlate with transcriptional regulation of genes involved in a variety of biological processes necessary for neuroblast function/homeostasis. We identified an ASC-Notch regulated TF network that includes likely prime regulators of neuroblast function. Using a cohort of ASC target genes, we report that ASC null neuroblasts are defectively specified, remaining initially stalled, unable to divide, and lacking expression of many proneural targets. When mutant neuroblasts eventually start proliferating, they produce compromised progeny. Reporter lines driven by proneural-bound enhancers display ASC dependency, suggesting that the partial neuroblast identity seen in the absence of ASC genes is likely driven by other, proneural-independent, cis-elements. Neuroblast impairment and the late differentiation defects of ASC mutants are corrected by ectodermal induction of individual ASC genes but not by individual members of the TF network downstream of ASC. However, in wild-type embryos, the induction of individual members of this network induces CNS hyperplasia, suggesting that they synergize with the activating function of ASC to consolidate the chromatin dynamics that promote neural specification. Conclusions We demonstrate that ASC proneural transcription factors are indispensable for the timely initiation of the neural stem cell program at the chromatin level by regulating a large number of enhancers in the vicinity of neural genes. This early chromatin remodeling is crucial for both neuroblast homeostasis as well as future progeny fidelity. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01300-8.
Collapse
|
65
|
Kenny C, Dilshat R, Seberg HE, Van Otterloo E, Bonde G, Helverson A, Franke CM, Steingrímsson E, Cornell RA. TFAP2 paralogs facilitate chromatin access for MITF at pigmentation and cell proliferation genes. PLoS Genet 2022; 18:e1010207. [PMID: 35580127 PMCID: PMC9159589 DOI: 10.1371/journal.pgen.1010207] [Citation(s) in RCA: 12] [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: 11/24/2021] [Revised: 06/01/2022] [Accepted: 04/19/2022] [Indexed: 12/13/2022] Open
Abstract
In developing melanocytes and in melanoma cells, multiple paralogs of the Activating-enhancer-binding Protein 2 family of transcription factors (TFAP2) contribute to expression of genes encoding pigmentation regulators, but their interaction with Microphthalmia transcription factor (MITF), a master regulator of these cells, is unclear. Supporting the model that TFAP2 facilitates MITF's ability to activate expression of pigmentation genes, single-cell seq analysis of zebrafish embryos revealed that pigmentation genes are only expressed in the subset of mitfa-expressing cells that also express tfap2 paralogs. To test this model in SK-MEL-28 melanoma cells we deleted the two TFAP2 paralogs with highest expression, TFAP2A and TFAP2C, creating TFAP2 knockout (TFAP2-KO) cells. We then assessed gene expression, chromatin accessibility, binding of TFAP2A and of MITF, and the chromatin marks H3K27Ac and H3K27Me3 which are characteristic of active enhancers and silenced chromatin, respectively. Integrated analyses of these datasets indicate TFAP2 paralogs directly activate enhancers near genes enriched for roles in pigmentation and proliferation, and directly repress enhancers near genes enriched for roles in cell adhesion. Consistently, compared to WT cells, TFAP2-KO cells proliferate less and adhere to one another more. TFAP2 paralogs and MITF co-operatively activate a subset of enhancers, with the former necessary for MITF binding and chromatin accessibility. By contrast, TFAP2 paralogs and MITF do not appear to co-operatively inhibit enhancers. These studies reveal a mechanism by which TFAP2 profoundly influences the set of genes activated by MITF, and thereby the phenotype of pigment cells and melanoma cells.
Collapse
Affiliation(s)
- Colin Kenny
- Department of Anatomy and Cell Biology, College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Ramile Dilshat
- Department of Biochemistry and Molecular Biology, BioMedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - Hannah E. Seberg
- Department of Anatomy and Cell Biology, College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Eric Van Otterloo
- Department of Anatomy and Cell Biology, College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Gregory Bonde
- Department of Anatomy and Cell Biology, College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Annika Helverson
- Department of Anatomy and Cell Biology, College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Christopher M. Franke
- Department of Surgery, College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Eiríkur Steingrímsson
- Department of Biochemistry and Molecular Biology, BioMedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - Robert A. Cornell
- Department of Anatomy and Cell Biology, College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| |
Collapse
|
66
|
Sheu KM, Hoffmann A. Functional Hallmarks of Healthy Macrophage Responses: Their Regulatory Basis and Disease Relevance. Annu Rev Immunol 2022; 40:295-321. [PMID: 35471841 PMCID: PMC10074967 DOI: 10.1146/annurev-immunol-101320-031555] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Macrophages are first responders for the immune system. In this role, they have both effector functions for neutralizing pathogens and sentinel functions for alerting other immune cells of diverse pathologic threats, thereby initiating and coordinating a multipronged immune response. Macrophages are distributed throughout the body-they circulate in the blood, line the mucosal membranes, reside within organs, and survey the connective tissue. Several reviews have summarized their diverse roles in different physiological scenarios and in the initiation or amplification of different pathologies. In this review, we propose that both the effector and the sentinel functions of healthy macrophages rely on three hallmark properties: response specificity, context dependence, and stimulus memory. When these hallmark properties are diminished, the macrophage's biological functions are impaired, which in turn results in increased risk for immune dysregulation, manifested by immune deficiency or autoimmunity. We review the evidence and the molecular mechanisms supporting these functional hallmarks.
Collapse
Affiliation(s)
- Katherine M Sheu
- Department of Microbiology, Immunology, and Molecular Genetics and Institute for Quantitative and Computational Biosciences, University of California, Los Angeles, California, USA;
| | - Alexander Hoffmann
- Department of Microbiology, Immunology, and Molecular Genetics and Institute for Quantitative and Computational Biosciences, University of California, Los Angeles, California, USA;
| |
Collapse
|
67
|
Schmidt-Ott U, Yoon Y. Evolution and loss of ß-catenin and TCF-dependent axis specification in insects. CURRENT OPINION IN INSECT SCIENCE 2022; 50:100877. [PMID: 35104659 PMCID: PMC9133022 DOI: 10.1016/j.cois.2022.100877] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 01/06/2022] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Mechanisms and evolution of primary axis specification in insects are discussed in the context of the roles of ß-catenin and TCF in polarizing metazoan embryos. Three hypotheses are presented. First, insects with sequential segmentation and posterior growth use cell-autonomous mechanisms for establishing embryo polarity via the nuclear ratio of ß-catenin and TCF. Second, TCF homologs establish competence for anterior specification. Third, the evolution of simultaneous segmentation mechanisms, also known as long-germ development, resulted in primary axis specification mechanisms that are independent of ß-catenin but reliant on TCF, a condition that preceded the frequent replacement of anterior determinants in long germ insects.
Collapse
Affiliation(s)
- Urs Schmidt-Ott
- University of Chicago, Dept. of Organismal Biology and Anatomy, 1027 East 57th Street, Chicago, IL 60637, USA.
| | - Yoseop Yoon
- University of California, Irvine, Dept. of Microbiology and Molecular Genetics, School of Medicine, 811 Health Sciences Rd., Med Sci B262, CA 92617, USA
| |
Collapse
|
68
|
Tutanov O, Shtam T, Grigor’eva A, Tupikin A, Tsentalovich Y, Tamkovich S. Blood Plasma Exosomes Contain Circulating DNA in Their Crown. Diagnostics (Basel) 2022; 12:diagnostics12040854. [PMID: 35453902 PMCID: PMC9027845 DOI: 10.3390/diagnostics12040854] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/21/2022] [Accepted: 03/28/2022] [Indexed: 01/13/2023] Open
Abstract
It is known that circulating DNA (cirDNA) is protected from nuclease activity by proteins that form macromolecular complexes with DNA. In addition, it was previously shown that cirDNA can bind to the outer surface of exosomes. NTA analysis and real-time PCR show that exosomes from healthy females (HF) or breast cancer patients (BCP) plasma contain less than 1.4 × 10−8 pg of DNA. Thus, only a minor part of cirDNA is attached to the outer side of the exosome as part of the vesicle crown: the share of exosomal DNA does not exceed 0.025% HF plasma DNA and 0.004% BCP plasma DNA. Treatment of plasma exosomes with DNase I with subsequent dot immunoassay reveals that H2a, H2b, and H3 histones are not part of the exosomal membrane, but are part of the cirDNA–protein macromolecular complex associated with the surface of the exosome either through interaction with DNA-binding proteins or with histone-binding proteins. Using bioinformatics approaches after identification by MALDI-TOF mass spectrometry, 16 exosomal DNA-binding proteins were identified. It was shown that four proteins—AIFM1, IGHM, CHD5, and KCNIP3—are candidates for DNA binding on the outer membrane of exosomes; the crown of exosomes may include five DNA-binding proteins: H2a, H2b, H3, IGHM, and ALB. Of note, AIFM1, IGHM, and CHD5 proteins are found only in HF plasma exosomes; KCNIP3 protein is identified only in BCP plasma exosomes; and H2a, H2b, H3, and ALB are revealed in all samples of plasma exosomes. Two histone-binding proteins, CHD5 and KDM6B, have been found in exosomes from HF plasma. The data obtained indicate that cirDNA preferentially binds to the outer membrane of exosomes by association with DNA-binding proteins.
Collapse
Affiliation(s)
- Oleg Tutanov
- V. Zelman Institute for Medicine and Psychology, Novosibirsk State University, 630090 Novosibirsk, Russia;
| | - Tatiana Shtam
- Petersburg Nuclear Physics Institute Named by B.P. Konstantinov of National Research Center “Kurchatov Institute”, 188300 Gatchina, Russia;
| | - Alina Grigor’eva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (A.G.); (A.T.)
| | - Alexey Tupikin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (A.G.); (A.T.)
| | - Yuri Tsentalovich
- International Tomography Center, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia;
| | - Svetlana Tamkovich
- V. Zelman Institute for Medicine and Psychology, Novosibirsk State University, 630090 Novosibirsk, Russia;
- Correspondence:
| |
Collapse
|
69
|
Balsalobre A, Drouin J. Pioneer factors as master regulators of the epigenome and cell fate. Nat Rev Mol Cell Biol 2022; 23:449-464. [PMID: 35264768 DOI: 10.1038/s41580-022-00464-z] [Citation(s) in RCA: 89] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2022] [Indexed: 12/23/2022]
Abstract
Pioneer factors are transcription factors with the unique ability to initiate opening of closed chromatin. The stability of cell identity relies on robust mechanisms that maintain the epigenome and chromatin accessibility to transcription factors. Pioneer factors counter these mechanisms to implement new cell fates through binding of DNA target sites in closed chromatin and introduction of active-chromatin histone modifications, primarily at enhancers. As master regulators of enhancer activation, pioneers are thus crucial for the implementation of correct cell fate decisions in development, and as such, they hold tremendous potential for therapy through cellular reprogramming. The power of pioneer factors to reshape the epigenome also presents an Achilles heel, as their misexpression has major pathological consequences, such as in cancer. In this Review, we discuss the emerging mechanisms of pioneer factor functions and their roles in cell fate specification, cellular reprogramming and cancer.
Collapse
Affiliation(s)
- Aurelio Balsalobre
- Laboratoire de génétique moléculaire, Institut de recherches cliniques de Montréal, Montreal, QC, Canada
| | - Jacques Drouin
- Laboratoire de génétique moléculaire, Institut de recherches cliniques de Montréal, Montreal, QC, Canada.
| |
Collapse
|
70
|
Özturan D, Morova T, Lack NA. Androgen Receptor-Mediated Transcription in Prostate Cancer. Cells 2022; 11:cells11050898. [PMID: 35269520 PMCID: PMC8909478 DOI: 10.3390/cells11050898] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/25/2022] [Accepted: 03/01/2022] [Indexed: 11/16/2022] Open
Abstract
Androgen receptor (AR)-mediated transcription is critical in almost all stages of prostate cancer (PCa) growth and differentiation. This process involves a complex interplay of coregulatory proteins, chromatin remodeling complexes, and other transcription factors that work with AR at cis-regulatory enhancer regions to induce the spatiotemporal transcription of target genes. This enhancer-driven mechanism is remarkably dynamic and undergoes significant alterations during PCa progression. In this review, we discuss the AR mechanism of action in PCa with a focus on how cis-regulatory elements modulate gene expression. We explore emerging evidence of genetic variants that can impact AR regulatory regions and alter gene transcription in PCa. Finally, we highlight several outstanding questions and discuss potential mechanisms of this critical transcription factor.
Collapse
Affiliation(s)
- Doğancan Özturan
- School of Medicine, Koç University, Istanbul 34450, Turkey;
- Koç University Research Centre for Translational Medicine (KUTTAM), Koç University, Istanbul 34450, Turkey
| | - Tunç Morova
- Vancouver Prostate Centre, Department of Urologic Sciences, University of British Columbia, Vancouver, BC V6H 3Z6, Canada;
| | - Nathan A. Lack
- School of Medicine, Koç University, Istanbul 34450, Turkey;
- Koç University Research Centre for Translational Medicine (KUTTAM), Koç University, Istanbul 34450, Turkey
- Vancouver Prostate Centre, Department of Urologic Sciences, University of British Columbia, Vancouver, BC V6H 3Z6, Canada;
- Correspondence: ; Tel.: +1-604-875-4411 (ext. 6417)
| |
Collapse
|
71
|
Barshad G, Webb LM, Ting HA, Oyesola OO, Onyekwere OG, Lewis JJ, Rice EJ, Matheson MK, Sun XH, von Moltke J, Danko CG, Tait Wojno ED. E-Protein Inhibition in ILC2 Development Shapes the Function of Mature ILC2s during Allergic Airway Inflammation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:1007-1020. [PMID: 35181641 DOI: 10.4049/jimmunol.2100414] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 12/09/2021] [Indexed: 01/16/2023]
Abstract
E-protein transcription factors limit group 2 innate lymphoid cell (ILC2) development while promoting T cell differentiation from common lymphoid progenitors. Inhibitors of DNA binding (ID) proteins block E-protein DNA binding in common lymphoid progenitors to allow ILC2 development. However, whether E-proteins influence ILC2 function upon maturity and activation remains unclear. Mice that overexpress ID1 under control of the thymus-restricted proximal Lck promoter (ID1tg/WT) have a large pool of primarily thymus-derived ILC2s in the periphery that develop in the absence of E-protein activity. We used these mice to investigate how the absence of E-protein activity affects ILC2 function and the genomic landscape in response to house dust mite (HDM) allergens. ID1tg/WT mice had increased KLRG1- ILC2s in the lung compared with wild-type (WT; ID1WT/WT) mice in response to HDM, but ID1tg/WT ILC2s had an impaired capacity to produce type 2 cytokines. Analysis of WT ILC2 accessible chromatin suggested that AP-1 and C/EBP transcription factors but not E-proteins were associated with ILC2 inflammatory gene programs. Instead, E-protein binding sites were enriched at functional genes in ILC2s during development that were later dynamically regulated in allergic lung inflammation, including genes that control ILC2 response to cytokines and interactions with T cells. Finally, ILC2s from ID1tg/WT compared with WT mice had fewer regions of open chromatin near functional genes that were enriched for AP-1 factor binding sites following HDM treatment. These data show that E-proteins shape the chromatin landscape during ILC2 development to dictate the functional capacity of mature ILC2s during allergic inflammation in the lung.
Collapse
Affiliation(s)
- Gilad Barshad
- Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY.,Department of Biomedical Sciences, Cornell University College of Veterinary Medicine, Ithaca, NY
| | - Lauren M Webb
- Department of Immunology, University of Washington, Seattle, WA;
| | - Hung-An Ting
- Department of Immunology, University of Washington, Seattle, WA
| | | | - Oluomachi G Onyekwere
- Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY.,Department of Microbiology and Immunology, Cornell University College of Veterinary Medicine, Ithaca, NY; and
| | - James J Lewis
- Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY.,Department of Biomedical Sciences, Cornell University College of Veterinary Medicine, Ithaca, NY
| | - Edward J Rice
- Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY.,Department of Biomedical Sciences, Cornell University College of Veterinary Medicine, Ithaca, NY
| | - Macy K Matheson
- Department of Immunology, University of Washington, Seattle, WA
| | - Xiao-Hong Sun
- Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | | | - Charles G Danko
- Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY.,Department of Biomedical Sciences, Cornell University College of Veterinary Medicine, Ithaca, NY
| | | |
Collapse
|
72
|
Pluripotency factors determine gene expression repertoire at zygotic genome activation. Nat Commun 2022; 13:788. [PMID: 35145080 PMCID: PMC8831532 DOI: 10.1038/s41467-022-28434-1] [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: 03/19/2020] [Accepted: 01/24/2022] [Indexed: 12/28/2022] Open
Abstract
Awakening of zygotic transcription in animal embryos relies on maternal pioneer transcription factors. The interplay of global and specific functions of these proteins remains poorly understood. Here, we analyze chromatin accessibility and time-resolved transcription in single and double mutant zebrafish embryos lacking pluripotency factors Pou5f3 and Sox19b. We show that two factors modify chromatin in a largely independent manner. We distinguish four types of direct enhancers by differential requirements for Pou5f3 or Sox19b. We demonstrate that changes in chromatin accessibility of enhancers underlie the changes in zygotic expression repertoire in the double mutants. Pou5f3 or Sox19b promote chromatin accessibility of enhancers linked to the genes involved in gastrulation and ventral fate specification. The genes regulating mesendodermal and dorsal fates are primed for activation independently of Pou5f3 and Sox19b. Strikingly, simultaneous loss of Pou5f3 and Sox19b leads to premature expression of genes, involved in regulation of organogenesis and differentiation. Zygotic genome activation in zebrafish relies on pluripotency transcription factors Pou5f3 and Sox19b. Here the authors investigate how these factors interact in vivo by analyzing the changes in chromatin state and time-resolved transcription in Pou5f3 and Sox19b single and double mutant embryos.
Collapse
|
73
|
Strader L, Weijers D, Wagner D. Plant transcription factors - being in the right place with the right company. CURRENT OPINION IN PLANT BIOLOGY 2022; 65:102136. [PMID: 34856504 PMCID: PMC8844091 DOI: 10.1016/j.pbi.2021.102136] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/29/2021] [Accepted: 10/04/2021] [Indexed: 05/15/2023]
Abstract
Transcriptional regulation underlies many of the growth and developmental processes that shape plants as well as their adaptation to their environment. Key to transcriptional control are transcription factors, DNA-binding proteins that serve two essential functions: to find the appropriate DNA contact sites in their target genes; and to recruit other proteins to execute transcriptional transactions. In recent years, protein structural, genomic, bioinformatic, and proteomic analyses have led to new insights into how these central functions are regulated. Here, we review new findings relating to plant transcription factor function and to their role in shaping transcription in the context of chromatin.
Collapse
Affiliation(s)
- Lucia Strader
- Department of Biology, Duke University, Durham, NC, USA
| | - Dolf Weijers
- Wageningen University, Laboratory of Biochemistry, Wageningen, the Netherlands
| | - Doris Wagner
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
74
|
Hansen JL, Loell KJ, Cohen BA. A test of the pioneer factor hypothesis using ectopic liver gene activation. eLife 2022; 11:73358. [PMID: 34984978 PMCID: PMC8849321 DOI: 10.7554/elife.73358] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 01/04/2022] [Indexed: 01/07/2023] Open
Abstract
The pioneer factor hypothesis (PFH) states that pioneer factors (PFs) are a subclass of transcription factors (TFs) that bind to and open inaccessible sites and then recruit non-pioneer factors (non-PFs) that activate batteries of silent genes. The PFH predicts that ectopic gene activation requires the sequential activity of qualitatively different TFs. We tested the PFH by expressing the endodermal PF FOXA1 and non-PF HNF4A in K562 lymphoblast cells. While co-expression of FOXA1 and HNF4A activated a burst of endoderm-specific gene expression, we found no evidence for a functional distinction between these two TFs. When expressed independently, both TFs bound and opened inaccessible sites, activated endodermal genes, and ‘pioneered’ for each other, although FOXA1 required fewer copies of its motif for binding. A subset of targets required both TFs, but the predominant mode of action at these targets did not conform to the sequential activity predicted by the PFH. From these results, we hypothesize an alternative to the PFH where ‘pioneer activity’ depends not on categorically different TFs but rather on the affinity of interaction between TF and DNA. Cells only use a fraction of their genetic information to make the proteins they need. The rest is carefully packaged away and tightly bundled in structures called nucleosomes. This physically shields the DNA from being accessed by transcription factors – the molecular actors that can read genes and kickstart the protein production process. Effectively, the genetic sequences inside nucleosomes are being silenced. However, during development, transcription factors must overcome this nucleosome barrier and activate silent genes to program cells. The pioneer factor hypothesis describes how this may be possible: first, ‘pioneer’ transcription factors can bind to and ‘open up’ nucleosomes to make target genes accessible. Then, non-pioneer factors can access the genetic sequence and recruit cofactors that begin copying the now-exposed genetic information. The widely accepted theory is based on studies of two proteins – FOXA1, an archetypal pioneer factor, and HNF4A, a non-pioneer factor – but the predictions of the pioneer factor hypothesis have yet to be explicitly tested. To do so, Hansen et al. expressed FOXA1 and HNF4A, separately and together, in cells which do not usually make these proteins. They then assessed how the proteins could bind to DNA and impact gene accessibility and transcription. The experiments demonstrate that FOXA1 and HNF4A do not necessarily follow the two-step activation predicted by the pioneer factor hypothesis. When expressed independently, both transcription factors bound and opened inaccessible sites, activated target genes, and ‘pioneered’ for each other. Similar patterns were observed across the genome. The only notable distinction between the two factors was that FOXA1, the archetypal pioneering factor, required fewer copies of its target sequence to bind DNA than HNF4A. These findings led Hansen et al. to propose an alternative theory to the pioneer factor hypothesis which eliminates the categorical distinction between pioneer and non-pioneer factors. Overall, this work has implications for how biologists understand the way that transcription factors activate silent genes during development.
Collapse
Affiliation(s)
- Jeffrey L Hansen
- Edison Center for Genome Sciences and Systems Biology, Washington University in St. Louis, St. Louis, United States.,Department of Genetics, Washington University in St. Louis, St. Louis, United States.,Medical Scientist Training Program, Washington University in St. Louis, St. Louis, United States
| | - Kaiser J Loell
- Edison Center for Genome Sciences and Systems Biology, Washington University in St. Louis, St. Louis, United States.,Department of Genetics, Washington University in St. Louis, St. Louis, United States
| | - Barak A Cohen
- Edison Center for Genome Sciences and Systems Biology, Washington University in St. Louis, St. Louis, United States.,Department of Genetics, Washington University in St. Louis, St. Louis, United States
| |
Collapse
|
75
|
Larson ED, Komori H, Gibson TJ, Ostgaard CM, Hamm DC, Schnell JM, Lee CY, Harrison MM. Cell-type-specific chromatin occupancy by the pioneer factor Zelda drives key developmental transitions in Drosophila. Nat Commun 2021; 12:7153. [PMID: 34887421 PMCID: PMC8660810 DOI: 10.1038/s41467-021-27506-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 11/24/2021] [Indexed: 12/14/2022] Open
Abstract
During Drosophila embryogenesis, the essential pioneer factor Zelda defines hundreds of cis-regulatory regions and in doing so reprograms the zygotic transcriptome. While Zelda is essential later in development, it is unclear how the ability of Zelda to define cis-regulatory regions is shaped by cell-type-specific chromatin architecture. Asymmetric division of neural stem cells (neuroblasts) in the fly brain provide an excellent paradigm for investigating the cell-type-specific functions of this pioneer factor. We show that Zelda synergistically functions with Notch to maintain neuroblasts in an undifferentiated state. Zelda misexpression reprograms progenitor cells to neuroblasts, but this capacity is limited by transcriptional repressors critical for progenitor commitment. Zelda genomic occupancy in neuroblasts is reorganized as compared to the embryo, and this reorganization is correlated with differences in chromatin accessibility and cofactor availability. We propose that Zelda regulates essential transitions in the neuroblasts and embryo through a shared gene-regulatory network driven by cell-type-specific enhancers.
Collapse
Affiliation(s)
- Elizabeth D Larson
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Hideyuki Komori
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Tyler J Gibson
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Cyrina M Ostgaard
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Danielle C Hamm
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Jack M Schnell
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Stem Cell and Regenerative Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
| | - Cheng-Yu Lee
- Division of Genetic Medicine, Department of Internal Medicine and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Melissa M Harrison
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
| |
Collapse
|
76
|
Cain B, Gebelein B. Mechanisms Underlying Hox-Mediated Transcriptional Outcomes. Front Cell Dev Biol 2021; 9:787339. [PMID: 34869389 PMCID: PMC8635045 DOI: 10.3389/fcell.2021.787339] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 10/28/2021] [Indexed: 11/13/2022] Open
Abstract
Metazoans differentially express multiple Hox transcription factors to specify diverse cell fates along the developing anterior-posterior axis. Two challenges arise when trying to understand how the Hox transcription factors regulate the required target genes for morphogenesis: First, how does each Hox factor differ from one another to accurately activate and repress target genes required for the formation of distinct segment and regional identities? Second, how can a Hox factor that is broadly expressed in many tissues within a segment impact the development of specific organs by regulating target genes in a cell type-specific manner? In this review, we highlight how recent genomic, interactome, and cis-regulatory studies are providing new insights into answering these two questions. Collectively, these studies suggest that Hox factors may differentially modify the chromatin of gene targets as well as utilize numerous interactions with additional co-activators, co-repressors, and sequence-specific transcription factors to achieve accurate segment and cell type-specific transcriptional outcomes.
Collapse
Affiliation(s)
- Brittany Cain
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Brian Gebelein
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| |
Collapse
|
77
|
Abstract
Transcription factors (TFs) are essential mediators of epigenetic regulation and modifiers of penetrance. Studies from the past decades have revealed a sub-class of TF that is capable of remodeling closed chromatin states through targeting nucleosomal motifs. This pioneer factor (PF) class of chromatin remodeler is ATP independent in its roles in epigenetic initiation, with nucleosome-motif recognition and association with repressive chromatin regions. Increasing evidence suggests that the fundamental properties of PFs can be coopted in human cancers. We explore the role of PFs in the larger context of tissue-specific epigenetic regulation. Moreover, we highlight an emerging class of chimeric PF derived from translocation partners in human disease and PFs associated with rare tumors. In the age of site-directed genome editing and targeted protein degradation, increasing our understanding of PFs will provide access to next-generation therapy for human disease driven from altered transcriptional circuitry.
Collapse
|
78
|
Colonnetta MM, Abrahante JE, Schedl P, Gohl DM, Deshpande G. CLAMP regulates zygotic genome activation in Drosophila embryos. Genetics 2021; 219:iyab107. [PMID: 34849887 PMCID: PMC8633140 DOI: 10.1093/genetics/iyab107] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 06/15/2020] [Indexed: 11/13/2022] Open
Abstract
Embryonic patterning is critically dependent on zygotic genome activation (ZGA). In Drosophila melanogaster embryos, the pioneer factor Zelda directs ZGA, possibly in conjunction with other factors. Here, we have explored the novel involvement of Chromatin-Linked Adapter for MSL Proteins (CLAMP) during ZGA. CLAMP binds thousands of sites genome-wide throughout early embryogenesis. Interestingly, CLAMP relocates to target promoter sequences across the genome when ZGA is initiated. Although there is a considerable overlap between CLAMP and Zelda binding sites, the proteins display distinct temporal dynamics. To assess whether CLAMP occupancy affects gene expression, we analyzed transcriptomes of embryos zygotically compromised for either clamp or zelda and found that transcript levels of many zygotically activated genes are similarly affected. Importantly, compromising either clamp or zelda disrupted the expression of critical segmentation and sex determination genes bound by CLAMP (and Zelda). Furthermore, clamp knockdown embryos recapitulate other phenotypes observed in Zelda-depleted embryos, including nuclear division defects, centrosome aberrations, and a disorganized actomyosin network. Based on these data, we propose that CLAMP acts in concert with Zelda to regulate early zygotic transcription.
Collapse
Affiliation(s)
- Megan M Colonnetta
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Juan E Abrahante
- University of Minnesota Informatics Institute, Minneapolis, MN 55455, USA
| | - Paul Schedl
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Daryl M Gohl
- University of Minnesota Genomics Center, Minneapolis, MN 55455, USA
| | - Girish Deshpande
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| |
Collapse
|
79
|
Yin P, Tong C. LncRNA RGMB-AS1 up-regulates ANKRD1 through competitively sponging miR-3614-5p to promote OSA cell proliferation and invasion. Arch Med Res 2021; 53:131-137. [PMID: 34583851 DOI: 10.1016/j.arcmed.2021.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/10/2021] [Accepted: 08/17/2021] [Indexed: 11/18/2022]
Abstract
BACKGROUND Osteosarcoma (OSA) is associated with unfavorable prognosis. The overall survival rate for patients with OSA recurrence or metastasis is only about 20%. Long non-coding RNAs (lncRNAs) significantly function in gene expression and the progression of various cancers including OSA. METHODS The expression of repulsive guidance molecule BMP co-receptor b antisense RNA 1 (RGMB-AS1) was detected in OSA cells via qRT-PCR. Western blot assay exposed the protein level of ankyrin repeat domain 1 (ANKRD1). The function assays showed the role of RGMB-AS1, miR-3614-5p, ANKRD1 on OSA cell proliferation and invasion. Subcellular Fraction assay was conducted to detect RGMB-AS1 localization. Rescue assays manifested the mechanism of RGMB-AS1/miR-3614-5p/ANKRD1 axis in OSA cells. RESULTS FOXA1-activated RGMB-AS1 positively regulated OSA cell progression including proliferation and invasion but negatively modulated apoptosis. miR-3614-5p interacted with RGMB-AS1 and functioned as the tumor suppressor in OSA cells. ANKRD1 was targeted by miR-3614-5p and was negatively interacted by miR-3614-5p. RGMB-AS1 and ANKRD1 competitively bound with miR-3614-5p. The suppression of silencing RGMB-AS1 on OSA cell progression was rescued by ANKRD1 overexpression or miR-3614-5p down-regulation. CONCLUSIONS FOXA1-activated RGMB-AS1 promoted cell proliferation and invasion in OSA via miR-3614-5p/ANKRD1 pathway.
Collapse
Affiliation(s)
- Peng Yin
- Department of Orthopaedic, the Second Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Changgui Tong
- Department of Hand and Foot Microsurgery, the Second Hospital of Dalian Medical University, Dalian, Liaoning, China.
| |
Collapse
|
80
|
Pelletier A, Mayran A, Gouhier A, Omichinski JG, Balsalobre A, Drouin J. Pax7 pioneer factor action requires both paired and homeo DNA binding domains. Nucleic Acids Res 2021; 49:7424-7436. [PMID: 34197620 PMCID: PMC8287922 DOI: 10.1093/nar/gkab561] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/02/2021] [Accepted: 06/15/2021] [Indexed: 12/20/2022] Open
Abstract
The pioneer transcription factor Pax7 contains two DNA binding domains (DBD), a paired and a homeo domain. Previous work on Pax7 and the related Pax3 showed that each DBD binds a cognate DNA sequence, thus defining two targets of binding and possibly modalities of action. Genomic targets of Pax7 pioneer action leading to chromatin opening are enriched for composite DNA target sites containing juxtaposed sites for both paired and homeo domains. The present work investigated the implication of the DBDs in pioneer action. We show that the composite sequence is a higher affinity binding site and that efficient binding to this site involves both DBDs of the same Pax7 molecule. This binding is not sensitive to cytosine methylation of the DNA sites consistent with pioneer action within nucleosomal heterochromatin. Introduction of single amino acid mutations in either paired or homeo domain that impair binding to cognate DNA sequences showed that both DBDs must be intact for pioneer action. In contrast, only the paired domain is required for low affinity binding of heterochromatin sites. Thus, Pax7 pioneer action on heterochromatin requires unique protein:DNA interactions that are more complex compared to its simpler DNA binding modalities at accessible enhancer target sites.
Collapse
Affiliation(s)
- Audrey Pelletier
- Laboratory of Molecular Genetics, Institut de recherches cliniques de Montréal (IRCM), Montréal QC H2W 1R7, Canada.,Department of Biochemistry, Faculté of Médecine, Université de Montréal, Montréal H3C 3J7, Canada
| | - Alexandre Mayran
- Laboratory of Molecular Genetics, Institut de recherches cliniques de Montréal (IRCM), Montréal QC H2W 1R7, Canada.,EPFL SV ISREC UPDUB, CH-1015 Lausanne, Switzerland
| | - Arthur Gouhier
- Laboratory of Molecular Genetics, Institut de recherches cliniques de Montréal (IRCM), Montréal QC H2W 1R7, Canada
| | - James G Omichinski
- Department of Biochemistry, Faculté of Médecine, Université de Montréal, Montréal H3C 3J7, Canada
| | - Aurelio Balsalobre
- Laboratory of Molecular Genetics, Institut de recherches cliniques de Montréal (IRCM), Montréal QC H2W 1R7, Canada
| | - Jacques Drouin
- Laboratory of Molecular Genetics, Institut de recherches cliniques de Montréal (IRCM), Montréal QC H2W 1R7, Canada.,Department of Biochemistry, Faculté of Médecine, Université de Montréal, Montréal H3C 3J7, Canada
| |
Collapse
|
81
|
Roberts GA, Ozkan B, Gachulincová I, O'Dwyer MR, Hall-Ponsele E, Saxena M, Robinson PJ, Soufi A. Dissecting OCT4 defines the role of nucleosome binding in pluripotency. Nat Cell Biol 2021; 23:834-845. [PMID: 34354236 PMCID: PMC7611526 DOI: 10.1038/s41556-021-00727-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 07/01/2021] [Indexed: 12/19/2022]
Abstract
Pioneer transcription factors such as OCT4 can target silent genes embedded in nucleosome-dense regions. How nucleosome interaction enables transcription factors to target chromatin and determine cell identity remains elusive. Here, we systematically dissect OCT4 to show that nucleosome binding is encoded within the DNA-binding domain and yet can be uncoupled from free-DNA binding. Furthermore, accelerating the binding kinetics of OCT4 to DNA enhances nucleosome binding. In cells, uncoupling nucleosome binding diminishes the ability of OCT4 to individually access closed chromatin, while more dynamic nucleosome binding results in expansive genome scanning within closed chromatin. However, both uncoupling and enhancing nucleosome binding are detrimental to inducing pluripotency from differentiated cells. Remarkably, stable interactions between OCT4 and nucleosomes are continuously required for maintaining the accessibility of pluripotency enhancers in stem cells. Our findings reveal how the affinity and residence time of OCT4-nucleosome complexes modulate chromatin accessibility during cell fate changes and maintenance.
Collapse
Affiliation(s)
- Gareth A Roberts
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, Institute of Stem Cell Research, University of Edinburgh, Edinburgh, UK
| | - Burak Ozkan
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, Institute of Stem Cell Research, University of Edinburgh, Edinburgh, UK
| | - Ivana Gachulincová
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, Institute of Stem Cell Research, University of Edinburgh, Edinburgh, UK
| | - Michael R O'Dwyer
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, Institute of Stem Cell Research, University of Edinburgh, Edinburgh, UK
| | - Elisa Hall-Ponsele
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, Institute of Stem Cell Research, University of Edinburgh, Edinburgh, UK
| | - Manoj Saxena
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK
| | - Philip J Robinson
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK
| | - Abdenour Soufi
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, Institute of Stem Cell Research, University of Edinburgh, Edinburgh, UK.
| |
Collapse
|
82
|
Bjarnason S, Ruidiaz SF, McIvor J, Mercadante D, Heidarsson PO. Protein intrinsic disorder on a dynamic nucleosomal landscape. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 183:295-354. [PMID: 34656332 DOI: 10.1016/bs.pmbts.2021.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The complex nucleoprotein landscape of the eukaryotic cell nucleus is rich in dynamic proteins that lack a stable three-dimensional structure. Many of these intrinsically disordered proteins operate directly on the first fundamental level of genome compaction: the nucleosome. Here we give an overview of how disordered interactions with and within nucleosomes shape the dynamics, architecture, and epigenetic regulation of the genetic material, controlling cellular transcription patterns. We highlight experimental and computational challenges in the study of protein disorder and illustrate how integrative approaches are increasingly unveiling the fine details of nuclear interaction networks. We finally dissect sequence properties encoded in disordered regions and assess common features of disordered nucleosome-binding proteins. As drivers of many critical biological processes, disordered proteins are integral to a comprehensive molecular view of the dynamic nuclear milieu.
Collapse
Affiliation(s)
- Sveinn Bjarnason
- Department of Biochemistry, Science Institute, University of Iceland, Reykjavík, Iceland
| | - Sarah F Ruidiaz
- Department of Biochemistry, Science Institute, University of Iceland, Reykjavík, Iceland
| | - Jordan McIvor
- School of Chemical Science, University of Auckland, Auckland, New Zealand
| | - Davide Mercadante
- School of Chemical Science, University of Auckland, Auckland, New Zealand.
| | - Pétur O Heidarsson
- Department of Biochemistry, Science Institute, University of Iceland, Reykjavík, Iceland.
| |
Collapse
|
83
|
Decombe S, Loll F, Caccianini L, Affannoukoué K, Izeddin I, Mozziconacci J, Escudé C, Lopes J. Epigenetic rewriting at centromeric DNA repeats leads to increased chromatin accessibility and chromosomal instability. Epigenetics Chromatin 2021; 14:35. [PMID: 34321103 PMCID: PMC8317386 DOI: 10.1186/s13072-021-00410-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/18/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Centromeric regions of human chromosomes contain large numbers of tandemly repeated α-satellite sequences. These sequences are covered with constitutive heterochromatin which is enriched in trimethylation of histone H3 on lysine 9 (H3K9me3). Although well studied using artificial chromosomes and global perturbations, the contribution of this epigenetic mark to chromatin structure and genome stability remains poorly known in a more natural context. RESULTS Using transcriptional activator-like effectors (TALEs) fused to a histone lysine demethylase (KDM4B), we were able to reduce the level of H3K9me3 on the α-satellites repeats of human chromosome 7. We show that the removal of H3K9me3 affects chromatin structure by increasing the accessibility of DNA repeats to the TALE protein. Tethering TALE-demethylase to centromeric repeats impairs the recruitment of HP1α and proteins of Chromosomal Passenger Complex (CPC) on this specific centromere without affecting CENP-A loading. Finally, the epigenetic re-writing by the TALE-KDM4B affects specifically the stability of chromosome 7 upon mitosis, highlighting the importance of H3K9me3 in centromere integrity and chromosome stability, mediated by the recruitment of HP1α and the CPC. CONCLUSION Our cellular model allows to demonstrate the direct role of pericentromeric H3K9me3 epigenetic mark on centromere integrity and function in a natural context and opens interesting possibilities for further studies regarding the role of the H3K9me3 mark.
Collapse
Affiliation(s)
- Sheldon Decombe
- Laboratoire Structure et Instabilité des Génomes, INSERM U1154, CNRS UM7196, Muséum National d'Histoire Naturelle, 43 rue Cuvier, 75005, Paris, France.,DCCBR, University of Toronto, Toronto, ON, M5S 3E1, Canada
| | - François Loll
- Laboratoire Structure et Instabilité des Génomes, INSERM U1154, CNRS UM7196, Muséum National d'Histoire Naturelle, 43 rue Cuvier, 75005, Paris, France.,INSERM, UMR 1229, Regenerative Medicine and Skeleton, Université de Nantes, ONIRIS, 44042, Nantes, France
| | - Laura Caccianini
- Laboratoire Physico-Chimie, Institut Curie, CNRS UMR168, Paris-Science Lettres, Sorbonne Université, 75005, Paris, France
| | - Kévin Affannoukoué
- Institut Langevin, ESPCI Paris, PSL Université, CNRS, 75005, Paris, France.,Institut Fresnel, Aix Marseille Université CNRS Centrale Marseille, Marseille, France
| | - Ignacio Izeddin
- Institut Langevin, ESPCI Paris, PSL Université, CNRS, 75005, Paris, France
| | - Julien Mozziconacci
- Laboratoire Structure et Instabilité des Génomes, INSERM U1154, CNRS UM7196, Muséum National d'Histoire Naturelle, 43 rue Cuvier, 75005, Paris, France
| | - Christophe Escudé
- Laboratoire Structure et Instabilité des Génomes, INSERM U1154, CNRS UM7196, Muséum National d'Histoire Naturelle, 43 rue Cuvier, 75005, Paris, France
| | - Judith Lopes
- Laboratoire Structure et Instabilité des Génomes, INSERM U1154, CNRS UM7196, Muséum National d'Histoire Naturelle, 43 rue Cuvier, 75005, Paris, France.
| |
Collapse
|
84
|
Yu HV, Tao L, Llamas J, Wang X, Nguyen JD, Trecek T, Segil N. POU4F3 pioneer activity enables ATOH1 to drive diverse mechanoreceptor differentiation through a feed-forward epigenetic mechanism. Proc Natl Acad Sci U S A 2021; 118:e2105137118. [PMID: 34266958 PMCID: PMC8307294 DOI: 10.1073/pnas.2105137118] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During embryonic development, hierarchical cascades of transcription factors interact with lineage-specific chromatin structures to control the sequential steps in the differentiation of specialized cell types. While examples of transcription factor cascades have been well documented, the mechanisms underlying developmental changes in accessibility of cell type-specific enhancers remain poorly understood. Here, we show that the transcriptional "master regulator" ATOH1-which is necessary for the differentiation of two distinct mechanoreceptor cell types, hair cells in the inner ear and Merkel cells of the epidermis-is unable to access much of its target enhancer network in the progenitor populations of either cell type when it first appears, imposing a block to further differentiation. This block is overcome by a feed-forward mechanism in which ATOH1 first stimulates expression of POU4F3, which subsequently acts as a pioneer factor to provide access to closed ATOH1 enhancers, allowing hair cell and Merkel cell differentiation to proceed. Our analysis also indicates the presence of both shared and divergent ATOH1/POU4F3-dependent enhancer networks in hair cells and Merkel cells. These cells share a deep developmental lineage relationship, deriving from their common epidermal origin, and suggesting that this feed-forward mechanism preceded the evolutionary divergence of these very different mechanoreceptive cell types.
Collapse
Affiliation(s)
- Haoze V Yu
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Biology at University of Southern California, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| | - Litao Tao
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Biology at University of Southern California, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| | - Juan Llamas
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Biology at University of Southern California, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| | - Xizi Wang
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Biology at University of Southern California, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| | - John D Nguyen
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Biology at University of Southern California, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| | - Talon Trecek
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Biology at University of Southern California, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| | - Neil Segil
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Biology at University of Southern California, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033;
- Caruso Department of Otolaryngology - Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033
| |
Collapse
|
85
|
Sunkel BD, Wang M, LaHaye S, Kelly BJ, Fitch JR, Barr FG, White P, Stanton BZ. Evidence of pioneer factor activity of an oncogenic fusion transcription factor. iScience 2021; 24:102867. [PMID: 34386729 PMCID: PMC8346656 DOI: 10.1016/j.isci.2021.102867] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 06/07/2021] [Accepted: 07/14/2021] [Indexed: 11/29/2022] Open
Abstract
Recent characterizations of pioneer transcription factors provide insights into their structures and patterns of chromatin recognition associated with their roles in cell fate commitment and transformation. Intersecting with these basic science concepts, identification of pioneer factors (PFs) fused together as driver translocations in childhood cancers raises questions of whether these fusions retain the fundamental ability to invade repressed chromatin, consistent with their monomeric PF constituents. This study defines the cellular and chromatin localization of PAX3-FOXO1, an oncogenic driver of childhood rhabdomyosarcoma (RMS), derived from a fusion of PFs. To quantitatively define its chromatin-targeting functions and capacity to drive epigenetic reprogramming, we developed a ChIP-seq workflow with per-cell normalization (pc-ChIP-seq). Our quantitative localization studies address structural variation in RMS genomes and reveal insights into inactive chromatin localization of PAX3-FOXO1. Taken together, our studies are consistent with pioneer function for a driver oncoprotein in RMS, with repressed chromatin binding and nucleosome-motif targeting. The fusion oncoprotein PAX3-FOXO1 binds to both active and repressed chromatin PAX3-FOXO1-binding sites are adjacent to H3K9me3 domains PAX3-FOXO1 engages partial DNA motifs at early timepoints PAX3-FOXO1 can bind stably to inaccessible chromatin without inducing accessibility
Collapse
Affiliation(s)
- Benjamin D Sunkel
- Nationwide Children's Hospital, Center for Childhood Cancer and Blood Diseases, Columbus, OH 43205, USA
| | - Meng Wang
- Nationwide Children's Hospital, Center for Childhood Cancer and Blood Diseases, Columbus, OH 43205, USA
| | - Stephanie LaHaye
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Benjamin J Kelly
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - James R Fitch
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Frederic G Barr
- Laboratory of Pathology, National Cancer Institute, Bethesda, MD 20892, USA
| | - Peter White
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - Benjamin Z Stanton
- Nationwide Children's Hospital, Center for Childhood Cancer and Blood Diseases, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43210, USA.,Department of Biological Chemistry and Pharmacology, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| |
Collapse
|
86
|
Kobayashi W, Tachibana K. Awakening of the zygotic genome by pioneer transcription factors. Curr Opin Struct Biol 2021; 71:94-100. [PMID: 34256217 DOI: 10.1016/j.sbi.2021.05.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 05/31/2021] [Indexed: 10/20/2022]
Abstract
After fertilization, the genome of the totipotent embryo is transcriptionally inactive and then initiates bursts of transcription termed zygotic genome activation (ZGA). Despite the fundamental importance of initiating an embryonic transcription program for the start of life, the essential regulators and molecular mechanisms triggering ZGA in most organisms are poorly understood. One mechanism centers on pioneer factors that function in cellular reprogramming and differentiation. Recent studies revealed that not only a single but multiple pioneer factors bind cooperatively to the genome to open chromatin, resulting in changes in epigenetic modifications and triggering ZGA. Here, we review recent insights into the functions of pioneer factors during ZGA and discuss the potential relevance to three-dimensional chromatin organization during embryonic development.
Collapse
Affiliation(s)
- Wataru Kobayashi
- Department of Totipotency, Max Planck Institute of Biochemistry, Martinsried, Munich, Germany; Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna Biocenter, Vienna, Austria
| | - Kikuë Tachibana
- Department of Totipotency, Max Planck Institute of Biochemistry, Martinsried, Munich, Germany; Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna Biocenter, Vienna, Austria.
| |
Collapse
|
87
|
Yamaguchi N. LEAFY, a Pioneer Transcription Factor in Plants: A Mini-Review. FRONTIERS IN PLANT SCIENCE 2021; 12:701406. [PMID: 34290727 PMCID: PMC8287900 DOI: 10.3389/fpls.2021.701406] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/01/2021] [Indexed: 05/25/2023]
Abstract
A subset of eukaryotic transcription factors (TFs) possess the ability to reprogram one cell type into another. Genes important for cellular reprograming are typically located in closed chromatin, which is covered by nucleosomes. Pioneer factors are a special class of TFs that can initially engage their target sites in closed chromatin prior to the engagement with, opening of, or modification of the sites by other factors. Although many pioneer factors are known in animals, a few have been characterized in plants. The TF LEAFY (LFY) acts as a pioneer factor specifying floral fate in Arabidopsis. In response to endogenous and environmental cues, plants produce appropriate floral inducers (florigens). During the vegetative phase, LFY is repressed by the TERMINAL FLOWER 1 (TFL1)-FD complex, which functions as a floral inhibitor, or anti-florigen. The florigen FLOWERING LOCUS T (FT) competes with TFL1 to prevent the binding of the FD TF to the LFY locus. The resulting FT-FD complex functions as a transient stimulus to activate its targets. Once LFY has been transcribed in the appropriate spatiotemporal manner, LFY binds to nucleosomes in closed chromatin regions. Subsequently, LFY opens the chromatin by displacing H1 linker histones and recruiting the SWI/SNF chromatin-remodeling complex. Such local changes permit the binding of other TFs, leading to the expression of the floral meristem identity gene APETALA1. This mini-review describes the latest advances in our understanding of the pioneer TF LFY, providing insight into the establishment of gene expression competence through the shaping of the plant epigenetic landscape.
Collapse
|
88
|
Michael AK, Thomä NH. Reading the chromatinized genome. Cell 2021; 184:3599-3611. [PMID: 34146479 DOI: 10.1016/j.cell.2021.05.029] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 05/11/2021] [Accepted: 05/19/2021] [Indexed: 02/07/2023]
Abstract
Eukaryotic DNA-binding proteins operate in the context of chromatin, where nucleosomes are the elementary building blocks. Nucleosomal DNA is wrapped around a histone core, thereby rendering a large fraction of the DNA surface inaccessible to DNA-binding proteins. Nevertheless, first responders in DNA repair and sequence-specific transcription factors bind DNA target sites obstructed by chromatin. While early studies examined protein binding to histone-free DNA, it is only now beginning to emerge how DNA sequences are interrogated on nucleosomes. These readout strategies range from the release of nucleosomal DNA from histones, to rotational/translation register shifts of the DNA motif, and nucleosome-specific DNA binding modes that differ from those observed on naked DNA. Since DNA motif engagement on nucleosomes strongly depends on position and orientation, we argue that motif location and nucleosome positioning co-determine protein access to DNA in transcription and DNA repair.
Collapse
Affiliation(s)
- Alicia K Michael
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Nicolas H Thomä
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland.
| |
Collapse
|
89
|
Priest DG, Bernardini A, Lou J, Mantovani R, Hinde E. Live cell dynamics of the NF-Y transcription factor. Sci Rep 2021; 11:10992. [PMID: 34040015 PMCID: PMC8155045 DOI: 10.1038/s41598-021-90081-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 04/29/2021] [Indexed: 11/24/2022] Open
Abstract
Transcription factors (TFs) are core players in the control of gene expression, evolutionarily selected to recognise a subset of specific DNA sequences and nucleate the recruitment of the transcriptional machinery. How TFs assemble and move in the nucleus to locate and bind their DNA targets and cause a transcriptional response, remains mostly unclear. NF-Y is a highly conserved, heterotrimeric TF with important roles in both housekeeping and lineage-specific gene expression, functioning as a promoter organiser. Despite a large number of biochemical, structural and genomic studies of NF-Y, there is a lack of experiments in single living cells; therefore, basic assumptions of NF-Y biology remain unproven in vivo. Here we employ a series of dynamic fluorescence microscopy methods (FLIM-FRET, NB, RICS and FRAP) to study NF-Y dynamics and complex formation in live cells. Specifically, we provide quantitative measurement of NF-Y subunit association and diffusion kinetics in the nucleus that collectively suggest NF-Y to move and bind chromatin as a trimeric complex in vivo.
Collapse
Affiliation(s)
- David G Priest
- School of Physics, University of Melbourne, Melbourne, VIC, Australia
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Andrea Bernardini
- Dipartimento di Bioscienze, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy
| | - Jieqiong Lou
- School of Physics, University of Melbourne, Melbourne, VIC, Australia
| | - Roberto Mantovani
- Dipartimento di Bioscienze, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy.
| | - Elizabeth Hinde
- School of Physics, University of Melbourne, Melbourne, VIC, Australia.
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia.
| |
Collapse
|
90
|
Heslop JA, Pournasr B, Liu JT, Duncan SA. GATA6 defines endoderm fate by controlling chromatin accessibility during differentiation of human-induced pluripotent stem cells. Cell Rep 2021; 35:109145. [PMID: 34010638 PMCID: PMC8202205 DOI: 10.1016/j.celrep.2021.109145] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 01/20/2021] [Accepted: 04/26/2021] [Indexed: 02/07/2023] Open
Abstract
In addition to driving specific gene expression profiles, transcriptional regulators are becoming increasingly recognized for their capacity to modulate chromatin structure. GATA6 is essential for the formation of definitive endoderm; however, the molecular basis defining the importance of GATA6 to endoderm commitment is poorly understood. The members of the GATA family of transcription factors have the capacity to bind and alter the accessibility of chromatin. Using pluripotent stem cells as a model of human development, we reveal that GATA6 is integral to the establishment of the endoderm enhancer network via the induction of chromatin accessibility and histone modifications. We additionally identify the chromatin-modifying complexes that interact with GATA6, defining the putative mechanisms by which GATA6 modulates chromatin architecture. The identified GATA6-dependent processes further our knowledge of the molecular mechanisms that underpin cell-fate decisions during formative development.
Collapse
Affiliation(s)
- James A Heslop
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Behshad Pournasr
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Jui-Tung Liu
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Stephen A Duncan
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA.
| |
Collapse
|
91
|
The transcription factor code: a beacon for histone methyltransferase docking. Trends Cell Biol 2021; 31:792-800. [PMID: 34016504 DOI: 10.1016/j.tcb.2021.04.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/30/2021] [Accepted: 04/08/2021] [Indexed: 12/19/2022]
Abstract
Histone methylation is required for the establishment and maintenance of gene expression patterns that determine cellular identity, and its perturbation often leads to aberrant development and disease. Recruitment of histone methyltransferases (HMTs) to gene regulatory elements (GREs) of developmental genes is important for the correct activation and silencing of these genes, but the drivers of this recruitment are largely unknown. Here we propose that lineage-instructive transcription factors (Lin-TFs) act as general recruiters of HMT complexes to cell type-specific GREs through protein-protein interactions. We also postulate that the specificity of these interactions is dictated by Lin-TF post-translational modifications (PTMs), which act as a 'transcription factor code' that can determine the directionality of cell fate decisions during differentiation and development.
Collapse
|
92
|
Lai X, Blanc-Mathieu R, GrandVuillemin L, Huang Y, Stigliani A, Lucas J, Thévenon E, Loue-Manifel J, Turchi L, Daher H, Brun-Hernandez E, Vachon G, Latrasse D, Benhamed M, Dumas R, Zubieta C, Parcy F. The LEAFY floral regulator displays pioneer transcription factor properties. MOLECULAR PLANT 2021; 14:829-837. [PMID: 33684542 DOI: 10.1016/j.molp.2021.03.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/28/2021] [Accepted: 03/02/2021] [Indexed: 05/23/2023]
Abstract
Pioneer transcription factors (TFs) are a special category of TFs with the capacity to bind to closed chromatin regions in which DNA is wrapped around histones and may be highly methylated. Subsequently, pioneer TFs are able to modify the chromatin state to initiate gene expression. In plants, LEAFY (LFY) is a master floral regulator and has been suggested to act as a pioneer TF in Arabidopsis. Here, we demonstrate that LFY is able to bind both methylated and non-methylated DNA using a combination of in vitro genome-wide binding experiments and structural modeling. Comparisons between regions bound by LFY in vivo and chromatin accessibility data suggest that a subset of LFY bound regions is occupied by nucleosomes. We confirm that LFY is able to bind nucleosomal DNA in vitro using reconstituted nucleosomes. Finally, we show that constitutive LFY expression in seedling tissues is sufficient to induce chromatin accessibility in the LFY direct target genes APETALA1 and AGAMOUS. Taken together, our study suggests that LFY possesses key pioneer TF features that contribute to launching the floral gene expression program.
Collapse
Affiliation(s)
- Xuelei Lai
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Romain Blanc-Mathieu
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Loïc GrandVuillemin
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Ying Huang
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | - Arnaud Stigliani
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France; The Bioinformatics Centre, Department of Biology and Biotech and Research Innovation Centre, University of Copenhagen, Ole Maaløes Vej 5, DK2200 Copenhagen N, Denmark
| | - Jérémy Lucas
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Emmanuel Thévenon
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Jeanne Loue-Manifel
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France; Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, 69342 Lyon, France
| | - Laura Turchi
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Hussein Daher
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France; Institut de Biologie Structurale, Université Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Eugenia Brun-Hernandez
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Gilles Vachon
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - David Latrasse
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| | - Moussa Benhamed
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France; Université de Paris, Institute of Plant Sciences Paris-Saclay (IPS2), 75006 Paris, France
| | - Renaud Dumas
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - Chloe Zubieta
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France
| | - François Parcy
- Laboratoire Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG-DBSCI-LPCV, 17 avenue des martyrs, 38054, Grenoble, France.
| |
Collapse
|
93
|
Larson ED, Marsh AJ, Harrison MM. Pioneering the developmental frontier. Mol Cell 2021; 81:1640-1650. [PMID: 33689750 PMCID: PMC8052302 DOI: 10.1016/j.molcel.2021.02.020] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/28/2021] [Accepted: 02/16/2021] [Indexed: 12/16/2022]
Abstract
Coordinated changes in gene expression allow a single fertilized oocyte to develop into a complex multi-cellular organism. These changes in expression are controlled by transcription factors that gain access to discrete cis-regulatory elements in the genome, allowing them to activate gene expression. Although nucleosomes present barriers to transcription factor occupancy, pioneer transcription factors have unique properties that allow them to bind DNA in the context of nucleosomes, define cis-regulatory elements, and facilitate the subsequent binding of additional factors that determine gene expression. In this capacity, pioneer factors act at the top of gene-regulatory networks to control developmental transitions. Developmental context also influences pioneer factor binding and activity. Here we discuss the interplay between pioneer factors and development, their role in driving developmental transitions, and the influence of the cellular environment on pioneer factor binding and activity.
Collapse
Affiliation(s)
- Elizabeth D Larson
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Audrey J Marsh
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Melissa M Harrison
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
| |
Collapse
|
94
|
Structures of chromatin modulators in complex with nucleosome. Curr Opin Chem Biol 2021; 63:105-114. [PMID: 33823458 DOI: 10.1016/j.cbpa.2021.02.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/11/2021] [Accepted: 02/25/2021] [Indexed: 12/17/2022]
Abstract
The chromatin structure is dynamically regulated by many different modulators that post-translationally modify histones, replace canonical histones with histone variants, and unwind nucleosomal DNA, thereby modulating the accessibility of nucleosomal DNA and facilitating downstream DNA-templated nuclear processes. To understand how these modulators change the chromatin structure, it is essential to determine the 3D structures of chromatin modulators in complex with nucleosome. Here, we review the very recent progress in structural studies of some selected chromatin modulators in complex with nucleosome, including those of histone demethylases LSD1/2, some pioneer transcription factors, and the PWWP domain-containing protein LEDGF.
Collapse
|
95
|
Espiritu D, Gribkova AK, Gupta S, Shaytan AK, Panchenko AR. Molecular Mechanisms of Oncogenesis through the Lens of Nucleosomes and Histones. J Phys Chem B 2021; 125:3963-3976. [PMID: 33769808 DOI: 10.1021/acs.jpcb.1c00694] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
At the cellular level, cancer is the disease of both the genome and the epigenome, and the interplay between genetic mutations and epigenetic states may occur at the level of elementary chromatin units, the nucleosomes. They are formed by a segment of DNA wrapped around an octamer of histone proteins. In this review, we survey various mechanisms of cancer etiology and progression mediated by histones and nucleosomes. In particular, we discuss the effects of mutations in histones, changes in their expression and slicing on epigenetic dysregulation and carcinogenesis. The links between cancer phenotypes and differential expression of histone variants and isoforms are summarized. Finally, we discourse the geometric and steric effects of DNA compaction in nucleosomes on DNA mutation rate, interactions with transcription factors, including pioneer transcription factors, and prospects of cancer cells' genome and epigenome editing.
Collapse
Affiliation(s)
- Daniel Espiritu
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Anna K Gribkova
- Department of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, Moscow, 119991, Russia.,Sirius University of Science and Technology, 1 Olympic Avenue, Sochi, 354340, Russia
| | - Shubhangi Gupta
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Alexey K Shaytan
- Department of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, Moscow, 119991, Russia.,Sirius University of Science and Technology, 1 Olympic Avenue, Sochi, 354340, Russia.,Bioinformatics Lab, Faculty of Computer Science, HSE University, 11 Pokrovsky Boulevard, Moscow, 109028, Russia
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, Kingston, Ontario, Canada.,Ontario Institute of Cancer Research, Toronto, Ontario, Canada
| |
Collapse
|
96
|
Understanding transcription across scales: From base pairs to chromosomes. Mol Cell 2021; 81:1601-1616. [PMID: 33770487 DOI: 10.1016/j.molcel.2021.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/23/2021] [Accepted: 02/26/2021] [Indexed: 02/07/2023]
Abstract
The influence of genome organization on transcription is central to our understanding of cell type specification. Higher-order genome organization is established through short- and long-range DNA interactions. Coordination of these interactions, from single atoms to entire chromosomes, plays a fundamental role in transcriptional control of gene expression. Loss of this coupling can result in disease. Analysis of transcriptional regulation typically involves disparate experimental approaches, from structural studies that define angstrom-level interactions to cell-biological and genomic approaches that assess mesoscale relationships. Thus, to fully understand the mechanisms that regulate gene expression, it is critical to integrate the findings gained across these distinct size scales. In this review, I illustrate fundamental ways in which cells regulate transcription in the context of genome organization.
Collapse
|
97
|
Pease NA, Nguyen PHB, Woodworth MA, Ng KKH, Irwin B, Vaughan JC, Kueh HY. Tunable, division-independent control of gene activation timing by a polycomb switch. Cell Rep 2021; 34:108888. [PMID: 33761349 PMCID: PMC8024876 DOI: 10.1016/j.celrep.2021.108888] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 12/17/2020] [Accepted: 03/01/2021] [Indexed: 01/09/2023] Open
Abstract
During development, progenitors often differentiate many cell generations after receiving signals. These delays must be robust yet tunable for precise population size control. Polycomb repressive mechanisms, involving histone H3 lysine-27 trimethylation (H3K27me3), restrain the expression of lineage-specifying genes in progenitors and may delay their activation and ensuing differentiation. Here, we elucidate an epigenetic switch controlling the T cell commitment gene Bcl11b that holds its locus in a heritable inactive state for multiple cell generations before activation. Integrating experiments and modeling, we identify a mechanism where H3K27me3 levels at Bcl11b, regulated by methyltransferase and demethylase activities, set the time delay at which the locus switches from a compacted, silent state to an extended, active state. This activation delay robustly spans many cell generations, is tunable by chromatin modifiers and transcription factors, and is independent of cell division. With their regulatory flexibility, such timed epigenetic switches may broadly control timing in development.
Collapse
Affiliation(s)
- Nicholas A Pease
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA; Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98195, USA
| | - Phuc H B Nguyen
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA; Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA 98195, USA
| | - Marcus A Woodworth
- Biological Physics, Structure and Design Program, University of Washington, Seattle, WA 98195, USA; Department of Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Kenneth K H Ng
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Blythe Irwin
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Joshua C Vaughan
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA; Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195, USA
| | - Hao Yuan Kueh
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA; Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
98
|
Interplay of BAF and MLL4 promotes cell type-specific enhancer activation. Nat Commun 2021; 12:1630. [PMID: 33712604 PMCID: PMC7955098 DOI: 10.1038/s41467-021-21893-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 02/10/2021] [Indexed: 01/05/2023] Open
Abstract
Cell type-specific enhancers are activated by coordinated actions of lineage-determining transcription factors (LDTFs) and chromatin regulators. The SWI/SNF chromatin remodeling complex BAF and the histone H3K4 methyltransferase MLL4 (KMT2D) are both implicated in enhancer activation. However, the interplay between BAF and MLL4 in enhancer activation remains unclear. Using adipogenesis as a model system, we identify BAF as the major SWI/SNF complex that colocalizes with MLL4 and LDTFs on active enhancers and is required for cell differentiation. In contrast, the promoter enriched SWI/SNF complex PBAF is dispensable for adipogenesis. By depleting BAF subunits SMARCA4 (BRG1) and SMARCB1 (SNF5) as well as MLL4 in cells, we show that BAF and MLL4 reciprocally regulate each other’s binding on active enhancers before and during adipogenesis. By focusing on enhancer activation by the adipogenic pioneer transcription factor C/EBPβ without inducing cell differentiation, we provide direct evidence for an interdependent relationship between BAF and MLL4 in activating cell type-specific enhancers. Together, these findings reveal a positive feedback between BAF and MLL4 in promoting LDTF-dependent activation of cell type-specific enhancers. The SWI/SNF complex BAF and the histone H3K4 methyltransferase MLL4 (KMT2D) play critical roles in enhancer activation, however the interplay between them has remained unclear. Here the authors show that BAF and MLL4 are interdependent in promoting enhancer activation by lineage-determining transcription factors during adipogenesis.
Collapse
|
99
|
Jung S, Appleton E, Ali M, Church GM, Del Sol A. A computer-guided design tool to increase the efficiency of cellular conversions. Nat Commun 2021; 12:1659. [PMID: 33712564 PMCID: PMC7954801 DOI: 10.1038/s41467-021-21801-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 02/09/2021] [Indexed: 02/07/2023] Open
Abstract
Human cell conversion technology has become an important tool for devising new cell transplantation therapies, generating disease models and testing gene therapies. However, while transcription factor over-expression-based methods have shown great promise in generating cell types in vitro, they often endure low conversion efficiency. In this context, great effort has been devoted to increasing the efficiency of current protocols and the development of computational approaches can be of great help in this endeavor. Here we introduce a computer-guided design tool that combines a computational framework for prioritizing more efficient combinations of instructive factors (IFs) of cellular conversions, called IRENE, with a transposon-based genomic integration system for efficient delivery. Particularly, IRENE relies on a stochastic gene regulatory network model that systematically prioritizes more efficient IFs by maximizing the agreement of the transcriptional and epigenetic landscapes between the converted and target cells. Our predictions substantially increased the efficiency of two established iPSC-differentiation protocols (natural killer cells and melanocytes) and established the first protocol for iPSC-derived mammary epithelial cells with high efficiency.
Collapse
Affiliation(s)
- Sascha Jung
- Computational Biology Group, CIC bioGUNE-BRTA (Basque Research and Technology Alliance), Bizkaia Technology Park, Derio, Spain
| | - Evan Appleton
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Muhammad Ali
- Computational Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
- Maastricht University School for Mental Health and Neuroscience (MHeNs), Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, the Netherlands
| | - George M Church
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- GC Therapeutics, Inc, Cambridge, MA, USA
| | - Antonio Del Sol
- Computational Biology Group, CIC bioGUNE-BRTA (Basque Research and Technology Alliance), Bizkaia Technology Park, Derio, Spain.
- Computational Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.
| |
Collapse
|
100
|
Chu JM, Pease NA, Kueh HY. In search of lost time: Enhancers as modulators of timing in lymphocyte development and differentiation. Immunol Rev 2021; 300:134-151. [PMID: 33734444 PMCID: PMC8005465 DOI: 10.1111/imr.12946] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/15/2020] [Accepted: 12/23/2020] [Indexed: 12/21/2022]
Abstract
Proper timing of gene expression is central to lymphocyte development and differentiation. Lymphocytes often delay gene activation for hours to days after the onset of signaling components, which act on the order of seconds to minutes. Such delays play a prominent role during the intricate choreography of developmental events and during the execution of an effector response. Though a number of mechanisms are sufficient to explain timing at short timescales, it is not known how timing delays are implemented over long timescales that may span several cell generations. Based on the literature, we propose that a class of cis-regulatory elements, termed "timing enhancers," may explain how timing delays are controlled over these long timescales. By considering chromatin as a kinetic barrier to state switching, the timing enhancer model explains experimentally observed dynamics of gene expression where other models fall short. In this review, we elaborate on features of the timing enhancer model and discuss the evidence for its generality throughout development and differentiation. We then discuss potential molecular mechanisms underlying timing enhancer function. Finally, we explore recent evidence drawing connections between timing enhancers and genetic risk for immunopathology. We argue that the timing enhancer model is a useful framework for understanding how cis-regulatory elements control the central dimension of timing in lymphocyte biology.
Collapse
Affiliation(s)
- Jonathan M Chu
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, Seattle, WA, USA
| | - Nicholas A Pease
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, Seattle, WA, USA
| | - Hao Yuan Kueh
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, Seattle, WA, USA
| |
Collapse
|