1
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Xu C, Kleinschmidt H, Yang J, Leith EM, Johnson J, Tan S, Mahony S, Bai L. Systematic dissection of sequence features affecting binding specificity of a pioneer factor reveals binding synergy between FOXA1 and AP-1. Mol Cell 2024; 84:2838-2855.e10. [PMID: 39019045 DOI: 10.1016/j.molcel.2024.06.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/23/2024] [Accepted: 06/21/2024] [Indexed: 07/19/2024]
Abstract
Despite the unique ability of pioneer factors (PFs) to target nucleosomal sites in closed chromatin, they only bind a small fraction of their genomic motifs. The underlying mechanism of this selectivity is not well understood. Here, we design a high-throughput assay called chromatin immunoprecipitation with integrated synthetic oligonucleotides (ChIP-ISO) to systematically dissect sequence features affecting the binding specificity of a classic PF, FOXA1, in human A549 cells. Combining ChIP-ISO with in vitro and neural network analyses, we find that (1) FOXA1 binding is strongly affected by co-binding transcription factors (TFs) AP-1 and CEBPB; (2) FOXA1 and AP-1 show binding cooperativity in vitro; (3) FOXA1's binding is determined more by local sequences than chromatin context, including eu-/heterochromatin; and (4) AP-1 is partially responsible for differential binding of FOXA1 in different cell types. Our study presents a framework for elucidating genetic rules underlying PF binding specificity and reveals a mechanism for context-specific regulation of its binding.
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Affiliation(s)
- Cheng Xu
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Holly Kleinschmidt
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jianyu Yang
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Erik M Leith
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jenna Johnson
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Song Tan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Shaun Mahony
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Lu Bai
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA; Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA; Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA.
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2
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Zhou BR, Feng H, Huang F, Zhu I, Portillo-Ledesma S, Shi D, Zaret KS, Schlick T, Landsman D, Wang Q, Bai Y. Structural insights into the cooperative nucleosome recognition and chromatin opening by FOXA1 and GATA4. Mol Cell 2024:S1097-2765(24)00592-6. [PMID: 39121853 DOI: 10.1016/j.molcel.2024.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 06/10/2024] [Accepted: 07/16/2024] [Indexed: 08/12/2024]
Abstract
Mouse FOXA1 and GATA4 are prototypes of pioneer factors, initiating liver cell development by binding to the N1 nucleosome in the enhancer of the ALB1 gene. Using cryoelectron microscopy (cryo-EM), we determined the structures of the free N1 nucleosome and its complexes with FOXA1 and GATA4, both individually and in combination. We found that the DNA-binding domains of FOXA1 and GATA4 mainly recognize the linker DNA and an internal site in the nucleosome, respectively, whereas their intrinsically disordered regions interact with the acidic patch on histone H2A-H2B. FOXA1 efficiently enhances GATA4 binding by repositioning the N1 nucleosome. In vivo DNA editing and bioinformatics analyses suggest that the co-binding mode of FOXA1 and GATA4 plays important roles in regulating genes involved in liver cell functions. Our results reveal the mechanism whereby FOXA1 and GATA4 cooperatively bind to the nucleosome through nucleosome repositioning, opening chromatin by bending linker DNA and obstructing nucleosome packing.
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Affiliation(s)
- Bing-Rui Zhou
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Hanqiao Feng
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Furong Huang
- Department of Pathology and Duke Cancer Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Iris Zhu
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephanie Portillo-Ledesma
- Department of Chemistry, New York University, 100 Washington Square East, Silver Building, New York, NY 10003, USA; Simons Center for Computational Physical Chemistry, New York University, 24 Waverly Place, Silver Building, New York, NY 10003, USA
| | - Dan Shi
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; Department of Cell and Development Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Tamar Schlick
- Department of Chemistry, New York University, 100 Washington Square East, Silver Building, New York, NY 10003, USA; Simons Center for Computational Physical Chemistry, New York University, 24 Waverly Place, Silver Building, New York, NY 10003, USA; Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, NY 10012, USA; New York University-East China Normal University Center for Computational Chemistry, New York University Shanghai, Shanghai 200122, China
| | - David Landsman
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20892, USA
| | - Qianben Wang
- Department of Pathology and Duke Cancer Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Yawen Bai
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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3
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Masoudi-Sobhanzadeh Y, Li S, Peng Y, Panchenko AR. Interpretable deep residual network uncovers nucleosome positioning and associated features. Nucleic Acids Res 2024:gkae623. [PMID: 39036965 DOI: 10.1093/nar/gkae623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 05/31/2024] [Accepted: 07/04/2024] [Indexed: 07/23/2024] Open
Abstract
Nucleosomes represent elementary building units of eukaryotic chromosomes and consist of DNA wrapped around a histone octamer flanked by linker DNA segments. Nucleosomes are central in epigenetic pathways and their genomic positioning is associated with regulation of gene expression, DNA replication, DNA methylation and DNA repair, among other functions. Building on prior discoveries that DNA sequences noticeably affect nucleosome positioning, our objective is to identify nucleosome positions and related features across entire genome. Here, we introduce an interpretable framework based on the concepts of deep residual networks (NuPoSe). Trained on high-coverage human experimental MNase-seq data, NuPoSe is able to learn sequence and structural patterns associated with nucleosome organization in human genome. NuPoSe can be also applied to unseen data from different organisms and cell types. Our findings point to 43 informative features, most of them constitute tri-nucleotides, di-nucleotides and one tetra-nucleotide. Most features are significantly associated with the nucleosomal structural characteristics, namely, periodicity of nucleosomal DNA and its location with respect to a histone octamer. Importantly, we show that features derived from the 27 bp linker DNA flanking nucleosomes contribute up to 10% to the quality of the prediction model. This, along with the comprehensive training sets, deep-learning architecture, and feature selection method, may contribute to the NuPoSe's 80-89% classification accuracy on different independent datasets.
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Affiliation(s)
| | - Shuxiang Li
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, K7L3N6, Canada
| | - Yunhui Peng
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, 430079, China
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, K7L3N6, Canada
- Department of Biology and Molecular Sciences, Queen's University, Kingston, K7L3N6, Canada
- School of Computing, Queen's University, Kingston, K7L3N6, Canada
- Ontario Institute of Cancer Research, Toronto, M5G 0A3, Canada
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4
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Carminati M, Vecchia L, Stoos L, Thomä NH. Pioneer factors: Emerging rules of engagement for transcription factors on chromatinized DNA. Curr Opin Struct Biol 2024; 88:102875. [PMID: 38991237 DOI: 10.1016/j.sbi.2024.102875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 06/12/2024] [Accepted: 06/12/2024] [Indexed: 07/13/2024]
Abstract
Pioneering transcription factors (TFs) can drive cell fate changes by binding their DNA motifs in a repressive chromatin environment. Recent structures illustrate emerging rules for nucleosome engagement: TFs distort the nucleosomal DNA to gain access or employ alternative DNA-binding modes with smaller footprints, they preferentially access solvent-exposed motifs near the entry/exit sites, and frequently interact with histones. The extent of TF-histone interactions, in turn, depends on the motif location on the nucleosome, the type of DNA-binding fold, and adjacent domains present. TF-histone interactions can phase TF motifs relative to nucleosomes, and we discuss how these complex and surprisingly diverse interactions between nucleosomes and TFs contribute to function.
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Affiliation(s)
- Manuel Carminati
- Swiss Institute for Experimental Cancer Research (ISREC), EPFL, Lausanne 1015, Switzerland
| | - Luca Vecchia
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Lisa Stoos
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Nicolas H Thomä
- Swiss Institute for Experimental Cancer Research (ISREC), EPFL, Lausanne 1015, Switzerland; Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland.
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5
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Freund MM, Harrison MM, Torres-Zelada EF. Exploring the reciprocity between pioneer factors and development. Development 2024; 151:dev201921. [PMID: 38958075 PMCID: PMC11266817 DOI: 10.1242/dev.201921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Development is regulated by coordinated changes in gene expression. Control of these changes in expression is largely governed by the binding of transcription factors to specific regulatory elements. However, the packaging of DNA into chromatin prevents the binding of many transcription factors. Pioneer factors overcome this barrier owing to unique properties that enable them to bind closed chromatin, promote accessibility and, in so doing, mediate binding of additional factors that activate gene expression. Because of these properties, pioneer factors act at the top of gene-regulatory networks and drive developmental transitions. Despite the ability to bind target motifs in closed chromatin, pioneer factors have cell type-specific chromatin occupancy and activity. Thus, developmental context clearly shapes pioneer-factor function. Here, we discuss this reciprocal interplay between pioneer factors and development: how pioneer factors control changes in cell fate and how cellular environment influences pioneer-factor binding and activity.
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Affiliation(s)
- Meghan M. Freund
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 52706, USA
| | - Melissa M. Harrison
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 52706, USA
| | - Eliana F. Torres-Zelada
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 52706, USA
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6
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Stoeber S, Godin H, Xu C, Bai L. Pioneer factors: nature or nurture? Crit Rev Biochem Mol Biol 2024:1-15. [PMID: 38778580 DOI: 10.1080/10409238.2024.2355885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Accepted: 05/13/2024] [Indexed: 05/25/2024]
Abstract
Chromatin is densely packed with nucleosomes, which limits the accessibility of many chromatin-associated proteins. Pioneer factors (PFs) are usually viewed as a special group of sequence-specific transcription factors (TFs) that can recognize nucleosome-embedded motifs, invade compact chromatin, and generate open chromatin regions. Through this process, PFs initiate a cascade of events that play key roles in gene regulation and cell differentiation. A current debate in the field is if PFs belong to a unique subset of TFs with intrinsic "pioneering activity", or if all TFs have the potential to function as PFs within certain cellular contexts. There are also different views regarding the key feature(s) that define pioneering activity. In this review, we present evidence from the literature related to these alternative views and discuss how to potentially reconcile them. It is possible that both intrinsic properties, like tight nucleosome binding and structural compatibility, and cellular conditions, like concentration and co-factor availability, are important for PF function.
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Affiliation(s)
- Shane Stoeber
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA, USA
| | - Holly Godin
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA, USA
| | - Cheng Xu
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA, USA
| | - Lu Bai
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA, USA
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
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7
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Ferrer J, Dimitrova N. Transcription regulation by long non-coding RNAs: mechanisms and disease relevance. Nat Rev Mol Cell Biol 2024; 25:396-415. [PMID: 38242953 PMCID: PMC11045326 DOI: 10.1038/s41580-023-00694-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2023] [Indexed: 01/21/2024]
Abstract
Long non-coding RNAs (lncRNAs) outnumber protein-coding transcripts, but their functions remain largely unknown. In this Review, we discuss the emerging roles of lncRNAs in the control of gene transcription. Some of the best characterized lncRNAs have essential transcription cis-regulatory functions that cannot be easily accomplished by DNA-interacting transcription factors, such as XIST, which controls X-chromosome inactivation, or imprinted lncRNAs that direct allele-specific repression. A growing number of lncRNA transcription units, including CHASERR, PVT1 and HASTER (also known as HNF1A-AS1) act as transcription-stabilizing elements that fine-tune the activity of dosage-sensitive genes that encode transcription factors. Genetic experiments have shown that defects in such transcription stabilizers often cause severe phenotypes. Other lncRNAs, such as lincRNA-p21 (also known as Trp53cor1) and Maenli (Gm29348) contribute to local activation of gene transcription, whereas distinct lncRNAs influence gene transcription in trans. We discuss findings of lncRNAs that elicit a function through either activation of their transcription, transcript elongation and processing or the lncRNA molecule itself. We also discuss emerging evidence of lncRNA involvement in human diseases, and their potential as therapeutic targets.
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Affiliation(s)
- Jorge Ferrer
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain.
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
| | - Nadya Dimitrova
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
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8
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Kobayashi W, Sappler AH, Bollschweiler D, Kümmecke M, Basquin J, Arslantas EN, Ruangroengkulrith S, Hornberger R, Duderstadt K, Tachibana K. Nucleosome-bound NR5A2 structure reveals pioneer factor mechanism by DNA minor groove anchor competition. Nat Struct Mol Biol 2024; 31:757-766. [PMID: 38409506 PMCID: PMC11102866 DOI: 10.1038/s41594-024-01239-0] [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: 06/02/2023] [Accepted: 01/31/2024] [Indexed: 02/28/2024]
Abstract
Gene expression during natural and induced reprogramming is controlled by pioneer transcription factors that initiate transcription from closed chromatin. Nr5a2 is a key pioneer factor that regulates zygotic genome activation in totipotent embryos, pluripotency in embryonic stem cells and metabolism in adult tissues, but the mechanism of its pioneer activity remains poorly understood. Here, we present a cryo-electron microscopy structure of human NR5A2 bound to a nucleosome. The structure shows that the conserved carboxy-terminal extension (CTE) loop of the NR5A2 DNA-binding domain competes with a DNA minor groove anchor of the nucleosome and releases entry-exit site DNA. Mutational analysis showed that NR5A2 D159 of the CTE is dispensable for DNA binding but required for stable nucleosome association and persistent DNA 'unwrapping'. These findings suggest that NR5A2 belongs to an emerging class of pioneer factors that can use DNA minor groove anchor competition to destabilize nucleosomes and facilitate gene expression during reprogramming.
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Affiliation(s)
- Wataru Kobayashi
- Department of Totipotency, Max Planck Institute of Biochemistry (MPIB), Munich, Germany
| | - Anna H Sappler
- Structure and Dynamics of Molecular Machines, MPIB, Munich, Germany
| | | | - Maximilian Kümmecke
- Department of Totipotency, Max Planck Institute of Biochemistry (MPIB), Munich, Germany
| | - Jérôme Basquin
- Department of Structural Cell Biology, Crystallization Facility, MPIB, Munich, Germany
| | - Eda Nur Arslantas
- Department of Totipotency, Max Planck Institute of Biochemistry (MPIB), Munich, Germany
| | | | - Renate Hornberger
- Department of Totipotency, Max Planck Institute of Biochemistry (MPIB), Munich, Germany
| | - Karl Duderstadt
- Structure and Dynamics of Molecular Machines, MPIB, Munich, Germany
- Department of Bioscience, Technical University of Munich, Garching, Germany
| | - Kikuë Tachibana
- Department of Totipotency, Max Planck Institute of Biochemistry (MPIB), Munich, Germany.
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9
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Kotomura N, Shimono Y, Ishihara S. CYP19A1 Expression Is Controlled by mRNA Stability of the Upstream Transcription Factor AP-2γ in Placental JEG3 Cells. Endocrinology 2024; 165:bqae055. [PMID: 38717933 DOI: 10.1210/endocr/bqae055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Indexed: 05/21/2024]
Abstract
CYP19A1 encodes aromatase, which converts testosterone to estrogen, and is induced during placental maturation. To elucidate the molecular mechanism underlying this function, histone methylation was analyzed using the placental cytotrophoblast cell line, JEG3. Treatment of JEG3 cells with 3-deazaneplanocin A, an inhibitor of several methyltransferases, resulted in increased CYP19A1 expression, accompanied by removal of the repressive mark H3K27me3 from the CYP19A1 promoter. However, this increase was not observed in cells treated with GSK126, another specific inhibitor for H3K27me3 methylation. Expression of TFAP2C, which encodes AP-2γ, a transcription factor that regulates CYP19A1, was also elevated on 3-deazaneplanocin A treatment. Interestingly, TFAP2C messenger RNA (mRNA) was readily degraded in JEG3 cells but protected from degradation in the presence of 3-deazaneplanocin A. TFAP2C mRNA contained N6-methyladenosines, which were reduced on drug treatment. These observations indicate that the TFAP2C mRNA undergoes adenosine methylation and rapid degradation, whereas 3-deazaneplanocin A suppresses methylation, resulting in an increase in AP-2γ levels. We conclude that the increase in AP-2γ expression via stabilization of the TFAP2C mRNA is likely to underlie the increased CYP19A1 expression.
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Affiliation(s)
- Naoe Kotomura
- Department of Biochemistry, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
| | - Yohei Shimono
- Department of Biochemistry, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
| | - Satoru Ishihara
- Department of Biochemistry, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
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10
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Lian T, Guan R, Zhou BR, Bai Y. Structural mechanism of synergistic targeting of the CX3CR1 nucleosome by PU.1 and C/EBPα. Nat Struct Mol Biol 2024; 31:633-643. [PMID: 38267599 DOI: 10.1038/s41594-023-01189-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 11/23/2023] [Indexed: 01/26/2024]
Abstract
Pioneer transcription factors are vital for cell fate changes. PU.1 and C/EBPα work together to regulate hematopoietic stem cell differentiation. However, how they recognize in vivo nucleosomal DNA targets remains elusive. Here we report the structures of the nucleosome containing the mouse genomic CX3CR1 enhancer DNA and its complexes with PU.1 alone and with both PU.1 and the C/EBPα DNA binding domain. Our structures reveal that PU.1 binds the DNA motif at the exit linker, shifting 17 bp of DNA into the core region through interactions with H2A, unwrapping ~20 bp of nucleosomal DNA. C/EBPα binding, aided by PU.1's repositioning, unwraps ~25 bp of entry DNA. The PU.1 Q218H mutation, linked to acute myeloid leukemia, disrupts PU.1-H2A interactions. PU.1 and C/EBPα jointly displace linker histone H1 and open the H1-condensed nucleosome array. Our study unveils how two pioneer factors can work cooperatively to open closed chromatin by altering DNA positioning in the nucleosome.
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Affiliation(s)
- Tengfei Lian
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Ruifang Guan
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Bing-Rui Zhou
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Yawen Bai
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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11
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Ma B, Liu D, Zheng M, Wang Z, Zhang D, Jian Y, Ma J, Fan Y, Chen Y, Gao Y, Liu J, Li X, Li L. Development of a Double-Stapled Peptide Stabilizing Both α-Helix and β-Sheet Structures for Degrading Transcription Factor AR-V7. JACS AU 2024; 4:816-827. [PMID: 38425893 PMCID: PMC10900202 DOI: 10.1021/jacsau.3c00795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/08/2024] [Accepted: 01/08/2024] [Indexed: 03/02/2024]
Abstract
Peptide drugs offer distinct advantages in therapeutics; however, their limited stability and membrane penetration abilities hinder their widespread application. One strategy to overcome these challenges is the hydrocarbon peptide stapling technique, which addresses issues such as poor conformational stability, weak proteolytic resistance, and limited membrane permeability. Nonetheless, while peptide stapling has successfully stabilized α-helical peptides, it has shown limited applicability for most β-sheet peptide motifs. In this study, we present the design of a novel double-stapled peptide capable of simultaneously stabilizing both α-helix and β-sheet structures. Our designed double-stapled peptide, named DSARTC, specifically targets the androgen receptor (AR) DNA binding domain and MDM2 as E3 ligase. Serving as a peptide-based PROTAC (proteolysis-targeting chimera), DSARTC exhibits the ability to degrade both the full-length AR and AR-V7. Molecular dynamics simulations and circular dichroism analysis validate the successful constraint of both secondary structures, demonstrating that DSARTC is a "first-in-class" heterogeneous-conformational double-stapled peptide drug candidate. Compared to its linear counterpart, DSARTC displays enhanced stability and an improved cell penetration ability. In an enzalutamide-resistant prostate cancer animal model, DSARTC effectively inhibits tumor growth and reduces the levels of both AR and AR-V7 proteins. These results highlight the potential of DSARTC as a more potent and specific peptide PROTAC for AR-V7. Furthermore, our findings provide a promising strategy for expanding the design of staple peptide-based PROTAC drugs, targeting a wide range of "undruggable" transcription factors.
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Affiliation(s)
- Bohan Ma
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Donghua Liu
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Mengjun Zheng
- School
of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, China
| | - Zhe Wang
- Institute
of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Dize Zhang
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Yanlin Jian
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Jian Ma
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Yizeng Fan
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Yule Chen
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Yang Gao
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Jing Liu
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
| | - Xiang Li
- School
of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, China
| | - Lei Li
- Department
of Urology, The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710049, China
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12
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Hao X, Zhao B, Towers M, Liao L, Monteiro EL, Xu X, Freeman C, Peng H, Tang HY, Havas A, Kossenkov AV, Berger SL, Adams PD, Speicher DW, Schultz D, Marmorstein R, Zaret KS, Zhang R. TXNRD1 drives the innate immune response in senescent cells with implications for age-associated inflammation. NATURE AGING 2024; 4:185-197. [PMID: 38267705 PMCID: PMC11210448 DOI: 10.1038/s43587-023-00564-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 12/22/2023] [Indexed: 01/26/2024]
Abstract
Sterile inflammation, also known as 'inflammaging', is a hallmark of tissue aging. Cellular senescence contributes to tissue aging, in part, through the secretion of proinflammatory factors collectively known as the senescence-associated secretory phenotype (SASP). The genetic variability of thioredoxin reductase 1 (TXNRD1) is associated with aging and age-associated phenotypes such as late-life survival, activity of daily living and physical performance in old age. TXNRD1's role in regulating tissue aging has been attributed to its enzymatic role in cellular redox regulation. Here, we show that TXNRD1 drives the SASP and inflammaging through the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) innate immune response pathway independently of its enzymatic activity. TXNRD1 localizes to cytoplasmic chromatin fragments and interacts with cGAS in a senescence-status-dependent manner, which is necessary for the SASP. TXNRD1 enhances the enzymatic activity of cGAS. TXNRD1 is required for both the tumor-promoting and immune surveillance functions of senescent cells, which are mediated by the SASP in vivo in mouse models. Treatment of aged mice with a TXNRD1 inhibitor that disrupts its interaction with cGAS, but not with an inhibitor of its enzymatic activity alone, downregulated markers of inflammaging in several tissues. In summary, our results show that TXNRD1 promotes the SASP through the innate immune response, with implications for inflammaging. This suggests that the TXNRD1-cGAS interaction is a relevant target for selectively suppressing inflammaging.
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Affiliation(s)
- Xue Hao
- Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Bo Zhao
- Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Martina Towers
- Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Liping Liao
- Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Edgar Luzete Monteiro
- Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Xin Xu
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Christina Freeman
- High-throughput Screening Core, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Hongzhuang Peng
- High-throughput Screening Core, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Hsin-Yao Tang
- Molecular and Cellular Oncogenesis Program, The Wistar Institute, Philadelphia, PA, USA
| | - Aaron Havas
- Sanford Burnham Prebys Medical Discovery Institute, San Diego, CA, USA
| | - Andrew V Kossenkov
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, PA, USA
| | - Shelley L Berger
- Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Peter D Adams
- Sanford Burnham Prebys Medical Discovery Institute, San Diego, CA, USA
| | - David W Speicher
- Molecular and Cellular Oncogenesis Program, The Wistar Institute, Philadelphia, PA, USA
| | - David Schultz
- High-throughput Screening Core, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ronen Marmorstein
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kenneth S Zaret
- Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rugang Zhang
- Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA, USA.
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13
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Barral A, Zaret KS. Pioneer factors: roles and their regulation in development. Trends Genet 2024; 40:134-148. [PMID: 37940484 PMCID: PMC10873006 DOI: 10.1016/j.tig.2023.10.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/06/2023] [Accepted: 10/06/2023] [Indexed: 11/10/2023]
Abstract
Pioneer factors are a subclass of transcription factors that can bind and initiate opening of silent chromatin regions. Pioneer factors subsequently regulate lineage-specific genes and enhancers and, thus, activate the zygotic genome after fertilization, guide cell fate transitions during development, and promote various forms of human cancers. As such, pioneer factors are useful in directed cell reprogramming. In this review, we define the structural and functional characteristics of pioneer factors, how they bind and initiate opening of closed chromatin regions, and the consequences for chromatin dynamics and gene expression during cell differentiation. We also discuss emerging mechanisms that modulate pioneer factors during development.
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Affiliation(s)
- Amandine Barral
- Institute for Regenerative Medicine and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Boulevard, Philadelphia, PA 19104, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Boulevard, Philadelphia, PA 19104, USA.
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14
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Peng Y, Song W, Teif VB, Ovcharenko I, Landsman D, Panchenko AR. Detection of new pioneer transcription factors as cell-type-specific nucleosome binders. eLife 2024; 12:RP88936. [PMID: 38293962 PMCID: PMC10945518 DOI: 10.7554/elife.88936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024] Open
Abstract
Wrapping of DNA into nucleosomes restricts accessibility to DNA and may affect the recognition of binding motifs by transcription factors. A certain class of transcription factors, the pioneer transcription factors, can specifically recognize their DNA binding sites on nucleosomes, initiate local chromatin opening, and facilitate the binding of co-factors in a cell-type-specific manner. For the majority of human pioneer transcription factors, the locations of their binding sites, mechanisms of binding, and regulation remain unknown. We have developed a computational method to predict the cell-type-specific ability of transcription factors to bind nucleosomes by integrating ChIP-seq, MNase-seq, and DNase-seq data with details of nucleosome structure. We have demonstrated the ability of our approach in discriminating pioneer from canonical transcription factors and predicted new potential pioneer transcription factors in H1, K562, HepG2, and HeLa-S3 cell lines. Last, we systematically analyzed the interaction modes between various pioneer transcription factors and detected several clusters of distinctive binding sites on nucleosomal DNA.
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Affiliation(s)
- Yunhui Peng
- Institute of Biophysics and Department of Physics, Central China Normal UniversityWuhanChina
- National Library of Medicine, National Institutes of HealthBethesdaUnited States
| | - Wei Song
- National Library of Medicine, National Institutes of HealthBethesdaUnited States
| | - Vladimir B Teif
- School of Life Sciences, University of Essex, Wivenhoe ParkColchesterUnited Kingdom
| | - Ivan Ovcharenko
- National Library of Medicine, National Institutes of HealthBethesdaUnited States
| | - David Landsman
- National Library of Medicine, National Institutes of HealthBethesdaUnited States
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, Queen’s UniversityKingstonCanada
- Department of Biology and Molecular Sciences, Queen’s UniversityKingstonCanada
- School of Computing, Queen’s UniversityKingstonCanada
- Ontario Institute of Cancer ResearchTorontoCanada
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15
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Xu W, Zhang H, Guo W, Jiang L, Zhao Y, Peng Y. Deciphering principles of nucleosome interactions and impact of cancer-associated mutations from comprehensive interaction network analysis. Brief Bioinform 2024; 25:bbad532. [PMID: 38329268 PMCID: PMC10851104 DOI: 10.1093/bib/bbad532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/30/2023] [Accepted: 12/23/2023] [Indexed: 02/09/2024] Open
Abstract
Nucleosomes represent hubs in chromatin organization and gene regulation and interact with a plethora of chromatin factors through different modes. In addition, alterations in histone proteins such as cancer mutations and post-translational modifications have profound effects on histone/nucleosome interactions. To elucidate the principles of histone interactions and the effects of those alterations, we developed histone interactomes for comprehensive mapping of histone-histone interactions (HHIs), histone-DNA interactions (HDIs), histone-partner interactions (HPIs) and DNA-partner interactions (DPIs) of 37 organisms, which contains a total of 3808 HPIs from 2544 binding proteins and 339 HHIs, 100 HDIs and 142 DPIs across 110 histone variants. With the developed networks, we explored histone interactions at different levels of granularities (protein-, domain- and residue-level) and performed systematic analysis on histone interactions at a large scale. Our analyses have characterized the preferred binding hotspots on both nucleosomal/linker DNA and histone octamer and unraveled diverse binding modes between nucleosome and different classes of binding partners. Last, to understand the impact of histone cancer-associated mutations on histone/nucleosome interactions, we complied one comprehensive cancer mutation dataset including 7940 cancer-associated histone mutations and further mapped those mutations onto 419,125 histone interactions at the residue level. Our quantitative analyses point to histone cancer-associated mutations' strongly disruptive effects on HHIs, HDIs and HPIs. We have further predicted 57 recurrent histone cancer mutations that have large effects on histone/nucleosome interactions and may have driver status in oncogenesis.
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Affiliation(s)
- Wang Xu
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, China
| | - Houfang Zhang
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, China
| | - Wenhan Guo
- Computational Science Program, University of Texas at El Paso, El Paso, TX 79902, USA
| | - Lijun Jiang
- Hubei Key Laboratory of Genetic Regulation & Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, China
| | - Yunjie Zhao
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, China
| | - Yunhui Peng
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, China
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16
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Ahmad K, Brahma S, Henikoff S. Epigenetic pioneering by SWI/SNF family remodelers. Mol Cell 2024; 84:194-201. [PMID: 38016477 PMCID: PMC10842064 DOI: 10.1016/j.molcel.2023.10.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 09/20/2023] [Accepted: 10/31/2023] [Indexed: 11/30/2023]
Abstract
In eukaryotic genomes, transcriptional machinery and nucleosomes compete for binding to DNA sequences; thus, a crucial aspect of gene regulatory element function is to modulate chromatin accessibility for transcription factor (TF) and RNA polymerase binding. Recent structural studies have revealed multiple modes of TF engagement with nucleosomes, but how initial "pioneering" results in steady-state DNA accessibility for further TF binding and RNA polymerase II (RNAPII) engagement has been unclear. Even less well understood is how distant sites of open chromatin interact with one another, such as when developmental enhancers activate promoters to release RNAPII for productive elongation. Here, we review evidence for the centrality of the conserved SWI/SNF family of nucleosome remodeling complexes, both in pioneering and in mediating enhancer-promoter contacts. Consideration of the nucleosome unwrapping and ATP hydrolysis activities of SWI/SNF complexes, together with their architectural features, may reconcile steady-state TF occupancy with rapid TF dynamics observed by live imaging.
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Affiliation(s)
- Kami Ahmad
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Sandipan Brahma
- University of Nebraska Medical Center, Department of Genetics, Cell Biology & Anatomy, Omaha, NE, USA
| | - Steven Henikoff
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA.
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17
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Lemma RB, Fuglerud BM, Frampton J, Gabrielsen OS. MYB: A Key Transcription Factor in the Hematopoietic System Subject to Many Levels of Control. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1459:3-29. [PMID: 39017837 DOI: 10.1007/978-3-031-62731-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
MYB is a master regulator and pioneer factor highly expressed in hematopoietic progenitor cells (HPCs) where it contributes to the reprogramming processes operating during hematopoietic development. MYB plays a complex role being involved in several lineages of the hematopoietic system. At the molecular level, the MYB gene is subject to intricate regulation at many levels through several enhancer and promoter elements, through transcriptional elongation control, as well as post-transcriptional regulation. The protein is modulated by post-translational modifications (PTMs) such as SUMOylation restricting the expression of its downstream targets. Together with a range of interaction partners, cooperating transcription factors (TFs) and epigenetic regulators, MYB orchestrates a fine-tuned symphony of genes expressed during various stages of haematopoiesis. At the same time, the complex MYB system is vulnerable, being a target for unbalanced control and cancer development.
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Affiliation(s)
- Roza Berhanu Lemma
- Department of Biosciences, University of Oslo, Oslo, Norway
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo, Norway
| | | | - Jon Frampton
- Department of Cancer & Genomic Sciences, College of Medicine & Health, University of Birmingham, Edgbaston, Birmingham, UK
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18
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Bulyk ML, Drouin J, Harrison MM, Taipale J, Zaret KS. Pioneer factors - key regulators of chromatin and gene expression. Nat Rev Genet 2023; 24:809-815. [PMID: 37740118 DOI: 10.1038/s41576-023-00648-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/02/2023] [Indexed: 09/24/2023]
Affiliation(s)
- Martha L Bulyk
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
| | - Jacques Drouin
- Laboratoire de génétique moléculaire, Institut de recherches cliniques de Montréal (IRCM), Montreal, Quebec, Canada.
- Département de Biochimie, Université de Montréal, Montreal, Quebec, Canada.
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada.
| | - Melissa M Harrison
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, USA.
| | - Jussi Taipale
- Department of Biochemistry, University of Cambridge, Cambridge, UK.
- Applied Tumour Genomics Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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19
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Horisawa K, Suzuki A. The role of pioneer transcription factors in the induction of direct cellular reprogramming. Regen Ther 2023; 24:112-116. [PMID: 37397229 PMCID: PMC10314230 DOI: 10.1016/j.reth.2023.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 06/01/2023] [Indexed: 07/04/2023] Open
Abstract
Regenerative medicine is a highly advanced medical field that aims to restore tissues and organs lost due to diseases and injury using a person's own cells or those of others. Direct cellular reprogramming is a promising technology that can directly induce cell-fate conversion from terminally differentiated cells to other cell types and is expected to play a pivotal role in applications in regenerative medicine. The induction of direct cellular reprogramming requires one or more master transcription factors with the potential to reconstitute cell type-specific transcription factor networks. The set of master transcription factors may contain unique transcription factors called pioneer factors that can open compacted chromatin structures and drive the transcriptional activation of target genes. Therefore, pioneer factors may play a central role in direct cellular reprogramming. However, our understanding of the molecular mechanisms by which pioneer factors induce cell-fate conversion is still limited. This review briefly summarizes the outcomes of recent findings and discusses future perspectives, focusing on the role of pioneer factors in direct cellular reprogramming.
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20
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Peng Y, Song W, Teif VB, Ovcharenko I, Landsman D, Panchenko AR. Detection of new pioneer transcription factors as cell-type specific nucleosome binders. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.10.540098. [PMID: 37425841 PMCID: PMC10327179 DOI: 10.1101/2023.05.10.540098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Wrapping of DNA into nucleosomes restricts accessibility to the DNA and may affect the recognition of binding motifs by transcription factors. A certain class of transcription factors, the pioneer transcription factors, can specifically recognize their DNA binding sites on nucleosomes, may initiate local chromatin opening and facilitate the binding of co-factors in a cell-type-specific manner. For the majority of human pioneer transcription factors, the locations of their binding sites, mechanisms of binding and regulation remain unknown. We have developed a computational method to predict the cell-type-specific ability of transcription factors to bind nucleosomes by integrating ChIP-seq, MNase-seq and DNase-seq data with details of nucleosome structure. We have demonstrated the ability of our approach in discriminating pioneer from canonical transcription factors and predicted new potential pioneer transcription factors in H1, K562, HepG2 and HeLa cell lines. Lastly, we systemically analyzed the interaction modes between various pioneer transcription factors and detected several clusters of distinctive binding sites on nucleosomal DNA.
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Affiliation(s)
- Yunhui Peng
- current address: Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, China
- National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Wei Song
- National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Vladimir B. Teif
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Ivan Ovcharenko
- National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - David Landsman
- National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Anna R. Panchenko
- Department of Pathology and Molecular Medicine, Queen’s University, ON, Canada
- Department of Biology and Molecular Sciences, Queen’s University, ON, Canada
- School of Computing, Queen’s University, ON, Canada
- Ontario Institute of Cancer Research, Toronto, ON, Canada
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21
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Lee SW, Frankston CM, Kim J. Epigenome editing in cancer: Advances and challenges for potential therapeutic options. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2023; 383:191-230. [PMID: 38359969 DOI: 10.1016/bs.ircmb.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Cancers are diseases caused by genetic and non-genetic environmental factors. Epigenetic alterations, some attributed to non-genetic factors, can lead to cancer development. Epigenetic changes can occur in tumor suppressors or oncogenes, or they may contribute to global cell state changes, making cells abnormal. Recent advances in gene editing technology show potential for cancer treatment. Herein, we will discuss our current knowledge of epigenetic alterations occurring in cancer and epigenetic editing technologies that can be applied to developing therapeutic options.
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Affiliation(s)
- Seung-Won Lee
- Cancer Early Detection Advanced Research Center, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, United States; Department of Molecular and Medical Genetics, School of Medicine, Oregon Health & Science University, Portland, OR, United States
| | - Connor Mitchell Frankston
- Cancer Early Detection Advanced Research Center, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, United States; Biomedical Engineering Graduate Program, Department of Biomedical Engineering, School of Medicine, Oregon Health & Science University, Portland, OR, United States
| | - Jungsun Kim
- Cancer Early Detection Advanced Research Center, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, United States; Department of Molecular and Medical Genetics, School of Medicine, Oregon Health & Science University, Portland, OR, United States; Cancer Biology Research Program, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, United States.
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22
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Xu C, Kleinschmidt H, Yang J, Leith E, Johnson J, Tan S, Mahony S, Bai L. Systematic Dissection of Sequence Features Affecting the Binding Specificity of a Pioneer Factor Reveals Binding Synergy Between FOXA1 and AP-1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.08.566246. [PMID: 37986839 PMCID: PMC10659273 DOI: 10.1101/2023.11.08.566246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Despite the unique ability of pioneer transcription factors (PFs) to target nucleosomal sites in closed chromatin, they only bind a small fraction of their genomic motifs. The underlying mechanism of this selectivity is not well understood. Here, we design a high-throughput assay called ChIP-ISO to systematically dissect sequence features affecting the binding specificity of a classic PF, FOXA1. Combining ChIP-ISO with in vitro and neural network analyses, we find that 1) FOXA1 binding is strongly affected by co-binding TFs AP-1 and CEBPB, 2) FOXA1 and AP-1 show binding cooperativity in vitro, 3) FOXA1's binding is determined more by local sequences than chromatin context, including eu-/heterochromatin, and 4) AP-1 is partially responsible for differential binding of FOXA1 in different cell types. Our study presents a framework for elucidating genetic rules underlying PF binding specificity and reveals a mechanism for context-specific regulation of its binding.
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Affiliation(s)
- Cheng Xu
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Holly Kleinschmidt
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jianyu Yang
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Erik Leith
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jenna Johnson
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Song Tan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Shaun Mahony
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Lu Bai
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
- Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA
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23
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Arora S, Yang J, Akiyama T, James DQ, Morrissey A, Blanda TR, Badjatia N, Lai WK, Ko MS, Pugh BF, Mahony S. Joint sequence & chromatin neural networks characterize the differential abilities of Forkhead transcription factors to engage inaccessible chromatin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.06.561228. [PMID: 37873361 PMCID: PMC10592618 DOI: 10.1101/2023.10.06.561228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
The DNA-binding activities of transcription factors (TFs) are influenced by both intrinsic sequence preferences and extrinsic interactions with cell-specific chromatin landscapes and other regulatory proteins. Disentangling the roles of these binding determinants remains challenging. For example, the FoxA subfamily of Forkhead domain (Fox) TFs are known pioneer factors that can bind to relatively inaccessible sites during development. Yet FoxA TF binding also varies across cell types, pointing to a combination of intrinsic and extrinsic forces guiding their binding. While other Forkhead domain TFs are often assumed to have pioneering abilities, how sequence and chromatin features influence the binding of related Fox TFs has not been systematically characterized. Here, we present a principled approach to compare the relative contributions of intrinsic DNA sequence preference and cell-specific chromatin environments to a TF's DNA-binding activities. We apply our approach to investigate how a selection of Fox TFs (FoxA1, FoxC1, FoxG1, FoxL2, and FoxP3) vary in their binding specificity. We over-express the selected Fox TFs in mouse embryonic stem cells, which offer a platform to contrast each TF's binding activity within the same preexisting chromatin background. By applying a convolutional neural network to interpret the Fox TF binding patterns, we evaluate how sequence and preexisting chromatin features jointly contribute to induced TF binding. We demonstrate that Fox TFs bind different DNA targets, and drive differential gene expression patterns, even when induced in identical chromatin settings. Despite the association between Forkhead domains and pioneering activities, the selected Fox TFs display a wide range of affinities for preexiting chromatin states. Using sequence and chromatin feature attribution techniques to interpret the neural network predictions, we show that differential sequence preferences combined with differential abilities to engage relatively inaccessible chromatin together explain Fox TF binding patterns at individual sites and genome-wide.
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Affiliation(s)
- Sonny Arora
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA
| | - Jianyu Yang
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA
| | - Tomohiko Akiyama
- Department of Systems Medicine, Keio University School of Medicine, Tokyo, Japan
- Current address: School of Medicine, Yokohama City University, Japan
| | - Daniela Q. James
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA
| | - Alexis Morrissey
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA
| | - Thomas R. Blanda
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA
| | - Nitika Badjatia
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA
| | - William K.M. Lai
- Department of Molecular Biology and Genetics, Cornell University, NY, USA
| | - Minoru S.H. Ko
- Department of Systems Medicine, Keio University School of Medicine, Tokyo, Japan
| | - B. Franklin Pugh
- Department of Molecular Biology and Genetics, Cornell University, NY, USA
| | - Shaun Mahony
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA
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24
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Zhao Z, D’Oliveira Albanus R, Taylor H, Tang X, Han Y, Orchard P, Varshney A, Zhang T, Manickam N, Erdos M, Narisu N, Taylor L, Saavedra X, Zhong A, Li B, Zhou T, Naji A, Liu C, Collins F, Parker SCJ, Chen S. An integrative single-cell multi-omics profiling of human pancreatic islets identifies T1D associated genes and regulatory signals. RESEARCH SQUARE 2023:rs.3.rs-3343318. [PMID: 37886586 PMCID: PMC10602166 DOI: 10.21203/rs.3.rs-3343318/v1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Genome wide association studies (GWAS) have identified over 100 signals associated with type 1 diabetes (T1D). However, translating any given T1D GWAS signal into mechanistic insights, including putative causal variants and the context (cell type and cell state) in which they function, has been limited. Here, we present a comprehensive multi-omic integrative analysis of single-cell/nucleus resolution profiles of gene expression and chromatin accessibility in healthy and autoantibody+ (AAB+) human islets, as well as islets under multiple T1D stimulatory conditions. We broadly nominate effector cell types for all T1D GWAS signals. We further nominated higher-resolution contexts, including effector cell types, regulatory elements, and genes for three independent T1D risk variants acting through islet cells within the pancreas at the DLK1/MEG3, RASGRP1, and TOX loci. Subsequently, we created isogenic gene knockouts DLK1-/-, RASGRP1-/-, and TOX-/-, and the corresponding regulatory region knockout, RASGRP1Δ, and DLK1Δ hESCs. Loss of RASGRP1 or DLK1, as well as knockout of the regulatory region of RASGRP1 or DLK1, increased β cell apoptosis. Additionally, pancreatic β cells derived from isogenic hESCs carrying the risk allele of rs3783355A/A exhibited increased β cell death. Finally, RNA-seq and ATAC-seq identified five genes upregulated in both RASGRP1-/- and DLK1-/- β-like cells, four of which are associated with T1D. Together, this work reports an integrative approach for combining single cell multi-omics, GWAS, and isogenic hESC-derived β-like cells to prioritize the T1D associated signals and their underlying context-specific cell types, genes, SNPs, and regulatory elements, to illuminate biological functions and molecular mechanisms.
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Affiliation(s)
- Zeping Zhao
- Department of Surgery, Weill Cornell Medicine, 1300 York Ave, New York, NY, 10065, USA
- Center for Genomic Health, Weill Cornell Medicine, 1300 York Ave, New York, NY 15 10065, USA
| | | | - Henry Taylor
- Center for Precision Health Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xuming Tang
- Department of Surgery, Weill Cornell Medicine, 1300 York Ave, New York, NY, 10065, USA
- Center for Genomic Health, Weill Cornell Medicine, 1300 York Ave, New York, NY 15 10065, USA
| | - Yuling Han
- Department of Surgery, Weill Cornell Medicine, 1300 York Ave, New York, NY, 10065, USA
- Center for Genomic Health, Weill Cornell Medicine, 1300 York Ave, New York, NY 15 10065, USA
| | - Peter Orchard
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Arushi Varshney
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Tuo Zhang
- Stem Cell Research Facility, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Nandini Manickam
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Mike Erdos
- Center for Precision Health Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Narisu Narisu
- Center for Precision Health Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Leland Taylor
- Center for Precision Health Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xiaxia Saavedra
- Department of Surgery, Weill Cornell Medicine, 1300 York Ave, New York, NY, 10065, USA
| | - Aaron Zhong
- Genomic Resource Core Facility, Weill Cornell Medical College, NY 10065, USA
| | - Bo Li
- Department of Surgery, Weill Cornell Medicine, 1300 York Ave, New York, NY, 10065, USA
| | - Ting Zhou
- Genomic Resource Core Facility, Weill Cornell Medical College, NY 10065, USA
| | - Ali Naji
- Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA19104, USA
| | - Chengyang Liu
- Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA19104, USA
| | - Francis Collins
- Center for Precision Health Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephen CJ Parker
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
- Department of Biostatistics, University of Michigan, Ann Arbor, MI, USA
| | - Shuibing Chen
- Department of Surgery, Weill Cornell Medicine, 1300 York Ave, New York, NY, 10065, USA
- Center for Genomic Health, Weill Cornell Medicine, 1300 York Ave, New York, NY 15 10065, USA
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25
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Brennan KJ, Weilert M, Krueger S, Pampari A, Liu HY, Yang AWH, Morrison JA, Hughes TR, Rushlow CA, Kundaje A, Zeitlinger J. Chromatin accessibility in the Drosophila embryo is determined by transcription factor pioneering and enhancer activation. Dev Cell 2023; 58:1898-1916.e9. [PMID: 37557175 PMCID: PMC10592203 DOI: 10.1016/j.devcel.2023.07.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 05/09/2023] [Accepted: 07/13/2023] [Indexed: 08/11/2023]
Abstract
Chromatin accessibility is integral to the process by which transcription factors (TFs) read out cis-regulatory DNA sequences, but it is difficult to differentiate between TFs that drive accessibility and those that do not. Deep learning models that learn complex sequence rules provide an unprecedented opportunity to dissect this problem. Using zygotic genome activation in Drosophila as a model, we analyzed high-resolution TF binding and chromatin accessibility data with interpretable deep learning and performed genetic validation experiments. We identify a hierarchical relationship between the pioneer TF Zelda and the TFs involved in axis patterning. Zelda consistently pioneers chromatin accessibility proportional to motif affinity, whereas patterning TFs augment chromatin accessibility in sequence contexts where they mediate enhancer activation. We conclude that chromatin accessibility occurs in two tiers: one through pioneering, which makes enhancers accessible but not necessarily active, and the second when the correct combination of TFs leads to enhancer activation.
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Affiliation(s)
- Kaelan J Brennan
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Melanie Weilert
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Sabrina Krueger
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Anusri Pampari
- Department of Computer Science, Stanford University, Palo Alto, CA 94305, USA
| | - Hsiao-Yun Liu
- Department of Biology, New York University, New York, NY 10003, USA
| | - Ally W H Yang
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Jason A Morrison
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Timothy R Hughes
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | | | - Anshul Kundaje
- Department of Computer Science, Stanford University, Palo Alto, CA 94305, USA; Department of Genetics, Stanford University, Palo Alto, CA 94305, USA
| | - Julia Zeitlinger
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA; Department of Pathology & Laboratory Medicine, The University of Kansas Medical Center, Kansas City, KS 66160, USA.
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26
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Riesle AJ, Gao M, Rosenblatt M, Hermes J, Hass H, Gebhard A, Veil M, Grüning B, Timmer J, Onichtchouk D. Activator-blocker model of transcriptional regulation by pioneer-like factors. Nat Commun 2023; 14:5677. [PMID: 37709752 PMCID: PMC10502082 DOI: 10.1038/s41467-023-41507-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 09/06/2023] [Indexed: 09/16/2023] Open
Abstract
Zygotic genome activation (ZGA) in the development of flies, fish, frogs and mammals depends on pioneer-like transcription factors (TFs). Those TFs create open chromatin regions, promote histone acetylation on enhancers, and activate transcription. Here, we use the panel of single, double and triple mutants for zebrafish genome activators Pou5f3, Sox19b and Nanog, multi-omics and mathematical modeling to investigate the combinatorial mechanisms of genome activation. We show that Pou5f3 and Nanog act differently on synergistic and antagonistic enhancer types. Pou5f3 and Nanog both bind as pioneer-like TFs on synergistic enhancers, promote histone acetylation and activate transcription. Antagonistic enhancers are activated by binding of one of these factors. The other TF binds as non-pioneer-like TF, competes with the activator and blocks all its effects, partially or completely. This activator-blocker mechanism mutually restricts widespread transcriptional activation by Pou5f3 and Nanog and prevents premature expression of late developmental regulators in the early embryo.
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Affiliation(s)
- Aileen Julia Riesle
- Department of Developmental Biology, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory, EMBL Rome, Adriano Buzzati-Traverso Campus, Via Ramarini 32, 00015, Monterotondo, RM, Italy
| | - Meijiang Gao
- Department of Developmental Biology, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
- Signalling Research centers BIOSS and CIBSS, 79104, Freiburg, Germany
| | - Marcus Rosenblatt
- Institute of Physics, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
- Freiburg Center for Data Analysis and Modelling (FDM), 79104, Freiburg, Germany
| | - Jacques Hermes
- Institute of Physics, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
- Freiburg Center for Data Analysis and Modelling (FDM), 79104, Freiburg, Germany
| | - Helge Hass
- Institute of Physics, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
- Freiburg Center for Data Analysis and Modelling (FDM), 79104, Freiburg, Germany
| | - Anna Gebhard
- Department of Developmental Biology, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
| | - Marina Veil
- Department of Developmental Biology, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany
| | - Björn Grüning
- Department of Computer Science, University of Freiburg, 79110, Freiburg, Germany
- Center for Biological Systems Analysis (ZBSA), University of Freiburg, 79104, Freiburg, Germany
| | - Jens Timmer
- Signalling Research centers BIOSS and CIBSS, 79104, Freiburg, Germany.
- Institute of Physics, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany.
- Freiburg Center for Data Analysis and Modelling (FDM), 79104, Freiburg, Germany.
| | - Daria Onichtchouk
- Department of Developmental Biology, Albert-Ludwigs-University of Freiburg, 79104, Freiburg, Germany.
- Signalling Research centers BIOSS and CIBSS, 79104, Freiburg, Germany.
- Institute of Developmental Biology RAS, 119991, Moscow, Russia.
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27
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Lian T, Guan R, Zhou BR, Bai Y. Structural mechanism of synergistic targeting of the CX3CR1 nucleosome by PU.1 and C/EBPα. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.25.554718. [PMID: 37790476 PMCID: PMC10542146 DOI: 10.1101/2023.08.25.554718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Pioneer transcription factors are vital for cell fate changes. PU.1 and C/EBPα work together to regulate hematopoietic stem cell differentiation. However, how they recognize in vivo nucleosomal DNA targets remain elusive. Here we report the structures of the nucleosome containing the mouse genomic CX3CR1 enhancer DNA and its complexes with PU.1 alone and with both PU.1 and the C/EBPα DNA binding domain. Our structures reveal that PU.1 binds the DNA motif at the exit linker, shifting 17 bp of DNA into the core region through interactions with H2A, unwrapping ~20 bp of nucleosomal DNA. C/EBPα binding, aided by PU.1's repositioning, unwraps ~25 bp entry DNA. The PU.1 Q218H mutation, linked to acute myeloid leukemia, disrupts PU.1-H2A interactions. PU.1 and C/EBPα jointly displace linker histone H1 and open the H1-condensed nucleosome array. Our study unveils how two pioneer factors can work cooperatively to open closed chromatin by altering DNA positioning in the nucleosome.
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Affiliation(s)
- Tengfei Lian
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
- These authors equally contributed to this work
| | - Ruifang Guan
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
- These authors equally contributed to this work
| | - Bing-Rui Zhou
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yawen Bai
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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28
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Liu A, Mair A, Matos JL, Vollbrecht M, Xu SL, Bergmann DC. Cell Fate Programming by Transcription Factors and Epigenetic Machinery in Stomatal Development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.23.554515. [PMID: 37662219 PMCID: PMC10473704 DOI: 10.1101/2023.08.23.554515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
The development of multi-cellular organisms requires coordinated changes in gene expression that are often mediated by the interaction between transcription factors (TFs) and their corresponding cis-regulatory elements (CREs). During development and differentiation, the accessibility of CREs is dynamically modulated by the epigenome. How the epigenome, CREs and TFs together exert control over cell fate commitment remains to be fully understood. In the Arabidopsis leaf epidermis, meristemoids undergo a series of stereotyped cell divisions, then switch fate to commit to stomatal differentiation. Newly created or reanalyzed scRNA-seq and ChIP-seq data confirm that stomatal development involves distinctive phases of transcriptional regulation and that differentially regulated genes are bound by the stomatal basic-helix-loop-helix (bHLH) TFs. Targets of the bHLHs often reside in repressive chromatin before activation. MNase-seq evidence further suggests that the repressive state can be overcome and remodeled upon activation by specific stomatal bHLHs. We propose that chromatin remodeling is mediated through the recruitment of a set of physical interactors that we identified through proximity labeling - the ATPase-dependent chromatin remodeling SWI/SNF complex and the histone acetyltransferase HAC1. The bHLHs and chromatin remodelers localize to overlapping genomic regions in a hierarchical order. Furthermore, plants with stage-specific knock-down of the SWI/SNF components or HAC1 fail to activate specific bHLH targets and display stomatal development defects. Together these data converge on a model for how stomatal TFs and epigenetic machinery cooperatively regulate transcription and chromatin remodeling during progressive fate specification.
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Affiliation(s)
- Ao Liu
- Howard Hughes Medical Institute, Stanford, CA, USA 94305
| | - Andrea Mair
- Howard Hughes Medical Institute, Stanford, CA, USA 94305
| | - Juliana L Matos
- Department of Biology, Stanford University, Stanford, CA, USA 94305
- Current address: Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, USA 94720
| | - Macy Vollbrecht
- Department of Biology, Stanford University, Stanford, CA, USA 94305
| | - Shou-Ling Xu
- Carnegie Institution for Science, Stanford, CA, USA 94305
- Carnegie Mass Spectrometry Facility, Carnegie Institution for Science, Stanford, CA, USA 94305
| | - Dominique C Bergmann
- Howard Hughes Medical Institute, Stanford, CA, USA 94305
- Department of Biology, Stanford University, Stanford, CA, USA 94305
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29
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Li Q, Liu X, Wen J, Chen X, Xie B, Zhao Y. Enhancer RNAs: mechanisms in transcriptional regulation and functions in diseases. Cell Commun Signal 2023; 21:191. [PMID: 37537618 PMCID: PMC10398997 DOI: 10.1186/s12964-023-01206-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 06/23/2023] [Indexed: 08/05/2023] Open
Abstract
In recent years, increasingly more non-coding RNAs have been detected with the development of high-throughput sequencing technology, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), small nucleolar RNAs (snoRNAs), and piwi-interacting RNA (piRNAs). The discovery of enhancer RNAs (eRNAs) in 2010 has further broadened the range of non-coding RNAs revealed. eRNAs are non-coding RNA molecules produced by the transcription of DNA cis-acting elements, enhancer fragments. Recent studies revealed that the transcription of eRNAs may be a biological marker responding to enhancer activity that can participate in the regulation of coding gene transcription. In this review, we discussed the biological characteristics of eRNAs, their functions in transcriptional regulation, the regulation factors of eRNAs production, and the research progress of eRNAs in different diseases. Video Abstract.
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Affiliation(s)
- Qianhui Li
- Department of Obstetrics and Gynecology, Department of Gynecologic Oncology Research Office, Guangzhou Key Laboratory of Targeted Therapy for Gynecologic Oncology, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, The Third Affiliated Hospital of Guangzhou Medical University, No.63 Duobao Road, Liwan District, Guangdong Province, Guangzhou City, 510150, People's Republic of China
| | - Xin Liu
- Department of Obstetrics and Gynecology, Department of Gynecologic Oncology Research Office, Guangzhou Key Laboratory of Targeted Therapy for Gynecologic Oncology, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, The Third Affiliated Hospital of Guangzhou Medical University, No.63 Duobao Road, Liwan District, Guangdong Province, Guangzhou City, 510150, People's Republic of China
| | - Jingtao Wen
- Department of Obstetrics and Gynecology, Department of Gynecologic Oncology Research Office, Guangzhou Key Laboratory of Targeted Therapy for Gynecologic Oncology, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, The Third Affiliated Hospital of Guangzhou Medical University, No.63 Duobao Road, Liwan District, Guangdong Province, Guangzhou City, 510150, People's Republic of China
| | - Xi Chen
- Department of Obstetrics and Gynecology, Department of Gynecologic Oncology Research Office, Guangzhou Key Laboratory of Targeted Therapy for Gynecologic Oncology, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, The Third Affiliated Hospital of Guangzhou Medical University, No.63 Duobao Road, Liwan District, Guangdong Province, Guangzhou City, 510150, People's Republic of China
| | - Bumin Xie
- Department of Obstetrics and Gynecology, Department of Gynecologic Oncology Research Office, Guangzhou Key Laboratory of Targeted Therapy for Gynecologic Oncology, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, The Third Affiliated Hospital of Guangzhou Medical University, No.63 Duobao Road, Liwan District, Guangdong Province, Guangzhou City, 510150, People's Republic of China
| | - Yang Zhao
- Department of Obstetrics and Gynecology, Department of Gynecologic Oncology Research Office, Guangzhou Key Laboratory of Targeted Therapy for Gynecologic Oncology, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, The Third Affiliated Hospital of Guangzhou Medical University, No.63 Duobao Road, Liwan District, Guangdong Province, Guangzhou City, 510150, People's Republic of China.
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30
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Liu H, Tsai H, Yang M, Li G, Bian Q, Ding G, Wu D, Dai J. Three-dimensional genome structure and function. MedComm (Beijing) 2023; 4:e326. [PMID: 37426677 PMCID: PMC10329473 DOI: 10.1002/mco2.326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 05/31/2023] [Accepted: 06/09/2023] [Indexed: 07/11/2023] Open
Abstract
Linear DNA undergoes a series of compression and folding events, forming various three-dimensional (3D) structural units in mammalian cells, including chromosomal territory, compartment, topologically associating domain, and chromatin loop. These structures play crucial roles in regulating gene expression, cell differentiation, and disease progression. Deciphering the principles underlying 3D genome folding and the molecular mechanisms governing cell fate determination remains a challenge. With advancements in high-throughput sequencing and imaging techniques, the hierarchical organization and functional roles of higher-order chromatin structures have been gradually illuminated. This review systematically discussed the structural hierarchy of the 3D genome, the effects and mechanisms of cis-regulatory elements interaction in the 3D genome for regulating spatiotemporally specific gene expression, the roles and mechanisms of dynamic changes in 3D chromatin conformation during embryonic development, and the pathological mechanisms of diseases such as congenital developmental abnormalities and cancer, which are attributed to alterations in 3D genome organization and aberrations in key structural proteins. Finally, prospects were made for the research about 3D genome structure, function, and genetic intervention, and the roles in disease development, prevention, and treatment, which may offer some clues for precise diagnosis and treatment of related diseases.
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Affiliation(s)
- Hao Liu
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
- School of StomatologyWeifang Medical UniversityWeifangChina
| | - Hsiangyu Tsai
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
| | - Maoquan Yang
- School of Clinical MedicineWeifang Medical UniversityWeifangChina
| | - Guozhi Li
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
| | - Qian Bian
- Shanghai Institute of Precision MedicineShanghaiChina
| | - Gang Ding
- School of StomatologyWeifang Medical UniversityWeifangChina
| | - Dandan Wu
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
| | - Jiewen Dai
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
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31
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Lerner J, Katznelson A, Zhang J, Zaret KS. Different chromatin-scanning modes lead to targeting of compacted chromatin by pioneer factors FOXA1 and SOX2. Cell Rep 2023; 42:112748. [PMID: 37405916 PMCID: PMC10529229 DOI: 10.1016/j.celrep.2023.112748] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 04/20/2023] [Accepted: 06/19/2023] [Indexed: 07/07/2023] Open
Abstract
Pioneer transcription factors interact with nucleosomes to scan silent, compact chromatin, enabling cooperative events that modulate gene activity. While at a subset of sites pioneer factors access chromatin by assisted loading with other transcription factors, the nucleosome-binding properties of pioneer factors enable them to initiate zygotic genome activation, embryonic development, and cellular reprogramming. To better understand nucleosome targeting in vivo, we assess whether pioneer factors FoxA1 and Sox2 target stable or unstable nucleosomes and find that they target DNase-resistant, stable nucleosomes, whereas HNF4A, a non-nucleosome binding factor, targets open, DNase-sensitive chromatin. Despite FOXA1 and SOX2 targeting similar proportions of DNase-resistant chromatin, using single-molecule tracking, we find that FOXA1 uses lower nucleoplasmic diffusion and longer residence times while SOX2 uses higher nucleoplasmic diffusion and shorter residence times to scan compact chromatin, while HNF4 scans compact chromatin much less efficiently. Thus, pioneer factors target compact chromatin through distinct processes.
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Affiliation(s)
- Jonathan Lerner
- Institute for Regenerative Medicine and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Andrew Katznelson
- Institute for Regenerative Medicine and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Jingchao Zhang
- Institute for Regenerative Medicine and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA.
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32
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Pownall ME, Miao L, Vejnar CE, M’Saad O, Sherrard A, Frederick MA, Benitez MD, Boswell CW, Zaret KS, Bewersdorf J, Giraldez AJ. Chromatin expansion microscopy reveals nanoscale organization of transcription and chromatin. Science 2023; 381:92-100. [PMID: 37410825 PMCID: PMC10372697 DOI: 10.1126/science.ade5308] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 05/17/2023] [Indexed: 07/08/2023]
Abstract
Nanoscale chromatin organization regulates gene expression. Although chromatin is notably reprogrammed during zygotic genome activation (ZGA), the organization of chromatin regulatory factors during this universal process remains unclear. In this work, we developed chromatin expansion microscopy (ChromExM) to visualize chromatin, transcription, and transcription factors in vivo. ChromExM of embryos during ZGA revealed how the pioneer factor Nanog interacts with nucleosomes and RNA polymerase II (Pol II), providing direct visualization of transcriptional elongation as string-like nanostructures. Blocking elongation led to more Pol II particles clustered around Nanog, with Pol II stalled at promoters and Nanog-bound enhancers. This led to a new model termed "kiss and kick", in which enhancer-promoter contacts are transient and released by transcriptional elongation. Our results demonstrate that ChromExM is broadly applicable to study nanoscale nuclear organization.
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Affiliation(s)
- Mark E. Pownall
- Department of Genetics, Yale University School of Medicine; New Haven, CT 06510, USA
| | - Liyun Miao
- Department of Genetics, Yale University School of Medicine; New Haven, CT 06510, USA
| | - Charles E. Vejnar
- Department of Genetics, Yale University School of Medicine; New Haven, CT 06510, USA
| | - Ons M’Saad
- Department of Cell Biology, Yale University School of Medicine; New Haven, CT 06510, USA
- Department of Biomedical Engineering, Yale University; New Haven, CT 06510, USA
| | - Alice Sherrard
- Department of Genetics, Yale University School of Medicine; New Haven, CT 06510, USA
| | - Megan A. Frederick
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Maria D.J. Benitez
- Department of Genetics, Yale University School of Medicine; New Haven, CT 06510, USA
| | - Curtis W. Boswell
- Department of Genetics, Yale University School of Medicine; New Haven, CT 06510, USA
| | - Kenneth S. Zaret
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Joerg Bewersdorf
- Department of Cell Biology, Yale University School of Medicine; New Haven, CT 06510, USA
- Kavli Institute for Neuroscience, Yale University School of Medicine; New Haven, CT 06510, USA
- Department of Biomedical Engineering, Yale University; New Haven, CT 06510, USA
- Department of Physics, Yale University; New Haven, CT 06510, USA
- Nanobiology Institute, Yale University; West Haven, CT 06477, USA
| | - Antonio J. Giraldez
- Department of Genetics, Yale University School of Medicine; New Haven, CT 06510, USA
- Yale Stem Cell Center, Yale University School of Medicine; New Haven, CT 06510, USA
- Yale Cancer Center, Yale University School of Medicine; New Haven, CT 06510, USA
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33
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Torcal Garcia G, Kowenz-Leutz E, Tian TV, Klonizakis A, Lerner J, De Andres-Aguayo L, Sapozhnikova V, Berenguer C, Carmona MP, Casadesus MV, Bulteau R, Francesconi M, Peiro S, Mertins P, Zaret K, Leutz A, Graf T. Carm1-arginine methylation of the transcription factor C/EBPα regulates transdifferentiation velocity. eLife 2023; 12:e83951. [PMID: 37365888 PMCID: PMC10299824 DOI: 10.7554/elife.83951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 05/30/2023] [Indexed: 06/28/2023] Open
Abstract
Here, we describe how the speed of C/EBPα-induced B cell to macrophage transdifferentiation (BMT) can be regulated, using both mouse and human models. The identification of a mutant of C/EBPα (C/EBPαR35A) that greatly accelerates BMT helped to illuminate the mechanism. Thus, incoming C/EBPα binds to PU.1, an obligate partner expressed in B cells, leading to the release of PU.1 from B cell enhancers, chromatin closing and silencing of the B cell program. Released PU.1 redistributes to macrophage enhancers newly occupied by C/EBPα, causing chromatin opening and activation of macrophage genes. All these steps are accelerated by C/EBPαR35A, initiated by its increased affinity for PU.1. Wild-type C/EBPα is methylated by Carm1 at arginine 35 and the enzyme's perturbations modulate BMT velocity as predicted from the observations with the mutant. Increasing the proportion of unmethylated C/EBPα in granulocyte/macrophage progenitors by inhibiting Carm1 biases the cell's differentiation toward macrophages, suggesting that cell fate decision velocity and lineage directionality are closely linked processes.
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Affiliation(s)
- Guillem Torcal Garcia
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
| | | | - Tian V Tian
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
- Vall d’Hebron Institute of Oncology (VHIO)BarcelonaSpain
| | - Antonis Klonizakis
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
| | - Jonathan Lerner
- Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Luisa De Andres-Aguayo
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
| | - Valeriia Sapozhnikova
- Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
| | - Clara Berenguer
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
| | - Marcos Plana Carmona
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
| | - Maria Vila Casadesus
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
- Vall d’Hebron Institute of Oncology (VHIO)BarcelonaSpain
| | - Romain Bulteau
- Laboratorie de Biologie et Modélisation de la Cellule, Université de LyonLyonFrance
| | - Mirko Francesconi
- Laboratorie de Biologie et Modélisation de la Cellule, Université de LyonLyonFrance
| | - Sandra Peiro
- Vall d’Hebron Institute of Oncology (VHIO)BarcelonaSpain
| | - Philipp Mertins
- Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
| | - Kenneth Zaret
- Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Achim Leutz
- Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
| | - Thomas Graf
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
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34
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Nguyen TT, Mitchell JM, Kiel MD, Jones KL, Williams TJ, Nichols JT, Van Otterloo E. TFAP2 paralogs regulate midfacial development in part through a conserved ALX genetic pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.16.545376. [PMID: 37398373 PMCID: PMC10312788 DOI: 10.1101/2023.06.16.545376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Cranial neural crest development is governed by positional gene regulatory networks (GRNs). Fine-tuning of the GRN components underly facial shape variation, yet how those in the midface are connected and activated remain poorly understood. Here, we show that concerted inactivation of Tfap2a and Tfap2b in the murine neural crest even during the late migratory phase results in a midfacial cleft and skeletal abnormalities. Bulk and single-cell RNA-seq profiling reveal that loss of both Tfap2 members dysregulated numerous midface GRN components involved in midface fusion, patterning, and differentiation. Notably, Alx1/3/4 (Alx) transcript levels are reduced, while ChIP-seq analyses suggest TFAP2 directly and positively regulates Alx gene expression. TFAP2 and ALX co-expression in midfacial neural crest cells of both mouse and zebrafish further implies conservation of this regulatory axis across vertebrates. Consistent with this notion, tfap2a mutant zebrafish present abnormal alx3 expression patterns, and the two genes display a genetic interaction in this species. Together, these data demonstrate a critical role for TFAP2 in regulating vertebrate midfacial development in part through ALX transcription factor gene expression.
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Affiliation(s)
- Timothy T Nguyen
- Iowa Institute for Oral Health Research, College of Dentistry & Dental Clinics, University of Iowa, Iowa City, IA, 52242, USA
- Department of Periodontics, College of Dentistry & Dental Clinics, University of Iowa, Iowa City, IA, 52242, USA
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA, 52242, USA
| | - Jennyfer M Mitchell
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Michaela D Kiel
- Iowa Institute for Oral Health Research, College of Dentistry & Dental Clinics, University of Iowa, Iowa City, IA, 52242, USA
- Department of Periodontics, College of Dentistry & Dental Clinics, University of Iowa, Iowa City, IA, 52242, USA
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Kenneth L Jones
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Children’s Hospital Colorado, Aurora, CO 80045, USA
| | - Trevor J Williams
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Children’s Hospital Colorado, Aurora, CO 80045, USA
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - James T Nichols
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Eric Van Otterloo
- Iowa Institute for Oral Health Research, College of Dentistry & Dental Clinics, University of Iowa, Iowa City, IA, 52242, USA
- Department of Periodontics, College of Dentistry & Dental Clinics, University of Iowa, Iowa City, IA, 52242, USA
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA, 52242, USA
- Craniofacial Anomalies Research Center, University of Iowa, Iowa City, IA, 52242, USA
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35
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Guan R, Lian T, Zhou BR, Wheeler D, Bai Y. Structural mechanism of LIN28B nucleosome targeting by OCT4. Mol Cell 2023; 83:1970-1982.e6. [PMID: 37327775 PMCID: PMC10276192 DOI: 10.1016/j.molcel.2023.05.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 03/31/2023] [Accepted: 05/19/2023] [Indexed: 06/18/2023]
Abstract
Pioneer transcription factors are essential for cell fate changes by targeting closed chromatin. OCT4 is a crucial pioneer factor that can induce cell reprogramming. However, the structural basis of how pioneer factors recognize the in vivo nucleosomal DNA targets is unknown. Here, we determine the high-resolution structures of the nucleosome containing human LIN28B DNA and its complexes with the OCT4 DNA binding region. Three OCT4s bind the pre-positioned nucleosome by recognizing non-canonical DNA sequences. Two use their POUS domains while the other uses the POUS-loop-POUHD region; POUHD serves as a wedge to unwrap ∼25 base pair DNA. Our analysis of previous genomic data and determination of the ESRRB-nucleosome-OCT4 structure confirmed the generality of these structural features. Moreover, biochemical studies suggest that multiple OCT4s cooperatively open the H1-condensed nucleosome array containing the LIN28B nucleosome. Thus, our study suggests a mechanism of how OCT4 can target the nucleosome and open closed chromatin.
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Affiliation(s)
- Ruifang Guan
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tengfei Lian
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Bing-Rui Zhou
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - David Wheeler
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yawen Bai
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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36
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McCarthy RL, Zhang J, Zaret KS. Diverse heterochromatin states restricting cell identity and reprogramming. Trends Biochem Sci 2023; 48:513-526. [PMID: 36990958 PMCID: PMC10182259 DOI: 10.1016/j.tibs.2023.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 02/16/2023] [Accepted: 02/24/2023] [Indexed: 03/29/2023]
Abstract
Heterochromatin is defined as a chromosomal domain harboring repressive H3K9me2/3 or H3K27me3 histone modifications and relevant factors that physically compact the chromatin. Heterochromatin can restrict where transcription factors bind, providing a barrier to gene activation and changes in cell identity. While heterochromatin thus helps maintain cell differentiation, it presents a barrier to overcome during efforts to reprogram cells for biomedical purposes. Recent findings have revealed complexity in the composition and regulation of heterochromatin, and shown that transiently disrupting the machinery of heterochromatin can enhance reprogramming. Here, we discuss how heterochromatin is established and maintained during development, and how our growing understanding of the mechanisms regulating H3K9me3 heterochromatin can be leveraged to improve our ability to direct changes in cell identity.
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Affiliation(s)
- Ryan L McCarthy
- Institute for Regenerative Medicine, Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jingchao Zhang
- Institute for Regenerative Medicine, Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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37
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Donovan BT, Chen H, Eek P, Meng Z, Jipa C, Tan S, Bai L, Poirier MG. Basic helix-loop-helix pioneer factors interact with the histone octamer to invade nucleosomes and generate nucleosome-depleted regions. Mol Cell 2023; 83:1251-1263.e6. [PMID: 36996811 PMCID: PMC10182836 DOI: 10.1016/j.molcel.2023.03.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 01/13/2023] [Accepted: 03/06/2023] [Indexed: 03/31/2023]
Abstract
Nucleosomes drastically limit transcription factor (TF) occupancy, while pioneer transcription factors (PFs) somehow circumvent this nucleosome barrier. In this study, we compare nucleosome binding of two conserved S. cerevisiae basic helix-loop-helix (bHLH) TFs, Cbf1 and Pho4. A cryo-EM structure of Cbf1 in complex with the nucleosome reveals that the Cbf1 HLH region can electrostatically interact with exposed histone residues within a partially unwrapped nucleosome. Single-molecule fluorescence studies show that the Cbf1 HLH region facilitates efficient nucleosome invasion by slowing its dissociation rate relative to DNA through interactions with histones, whereas the Pho4 HLH region does not. In vivo studies show that this enhanced binding provided by the Cbf1 HLH region enables nucleosome invasion and ensuing repositioning. These structural, single-molecule, and in vivo studies reveal the mechanistic basis of dissociation rate compensation by PFs and how this translates to facilitating chromatin opening inside cells.
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Affiliation(s)
- Benjamin T Donovan
- Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Hengye Chen
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Priit Eek
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Zhiyuan Meng
- Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Caroline Jipa
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | - Song Tan
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA; Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA.
| | - Lu Bai
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA; Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA.
| | - Michael G Poirier
- Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA; Department of Physics, The Ohio State University, Columbus, OH 43210, USA; Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
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38
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Chacin E, Reusswig KU, Furtmeier J, Bansal P, Karl LA, Pfander B, Straub T, Korber P, Kurat CF. Establishment and function of chromatin organization at replication origins. Nature 2023; 616:836-842. [PMID: 37020028 DOI: 10.1038/s41586-023-05926-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 03/03/2023] [Indexed: 04/07/2023]
Abstract
The origin recognition complex (ORC) is essential for initiation of eukaryotic chromosome replication as it loads the replicative helicase-the minichromosome maintenance (MCM) complex-at replication origins1. Replication origins display a stereotypic nucleosome organization with nucleosome depletion at ORC-binding sites and flanking arrays of regularly spaced nucleosomes2-4. However, how this nucleosome organization is established and whether this organization is required for replication remain unknown. Here, using genome-scale biochemical reconstitution with approximately 300 replication origins, we screened 17 purified chromatin factors from budding yeast and found that the ORC established nucleosome depletion over replication origins and flanking nucleosome arrays by orchestrating the chromatin remodellers INO80, ISW1a, ISW2 and Chd1. The functional importance of the nucleosome-organizing activity of the ORC was demonstrated by orc1 mutations that maintained classical MCM-loader activity but abrogated the array-generation activity of ORC. These mutations impaired replication through chromatin in vitro and were lethal in vivo. Our results establish that ORC, in addition to its canonical role as the MCM loader, has a second crucial function as a master regulator of nucleosome organization at the replication origin, a crucial prerequisite for efficient chromosome replication.
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Affiliation(s)
- Erika Chacin
- Biomedical Center Munich (BMC), Division of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Martinsried, Germany
| | - Karl-Uwe Reusswig
- Max Planck Institute of Biochemistry, DNA Replication and Genome Integrity, Martinsried, Germany
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Jessica Furtmeier
- Biomedical Center Munich (BMC), Division of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Martinsried, Germany
| | - Priyanka Bansal
- Biomedical Center Munich (BMC), Division of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Martinsried, Germany
| | - Leonhard A Karl
- Max Planck Institute of Biochemistry, DNA Replication and Genome Integrity, Martinsried, Germany
| | - Boris Pfander
- Max Planck Institute of Biochemistry, DNA Replication and Genome Integrity, Martinsried, Germany
- Genome Maintenance Mechanisms in Health and Disease, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
- Institute of Genome Stability in Aging and Disease, CECAD, University of Cologne, Medical Faculty, Cologne, Germany
| | - Tobias Straub
- Core Facility Bioinformatics, BMC, Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Martinsried, Germany
| | - Philipp Korber
- Biomedical Center Munich (BMC), Division of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Martinsried, Germany
| | - Christoph F Kurat
- Biomedical Center Munich (BMC), Division of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Martinsried, Germany.
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39
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Shi D, Huang Y, Bai C. Studies of the Mechanism of Nucleosome Dynamics: A Review on Multifactorial Regulation from Computational and Experimental Cases. Polymers (Basel) 2023; 15:polym15071763. [PMID: 37050377 PMCID: PMC10096840 DOI: 10.3390/polym15071763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/28/2023] [Accepted: 03/31/2023] [Indexed: 04/05/2023] Open
Abstract
The nucleosome, which organizes the long coil of genomic DNA in a highly condensed, polymeric way, is thought to be the basic unit of chromosomal structure. As the most important protein–DNA complex, its structural and dynamic features have been successively revealed in recent years. However, its regulatory mechanism, which is modulated by multiple factors, still requires systemic discussion. This study summarizes the regulatory factors of the nucleosome’s dynamic features from the perspective of histone modification, DNA methylation, and the nucleosome-interacting factors (transcription factors and nucleosome-remodeling proteins and cations) and focuses on the research exploring the molecular mechanism through both computational and experimental approaches. The regulatory factors that affect the dynamic features of nucleosomes are also discussed in detail, such as unwrapping, wrapping, sliding, and stacking. Due to the complexity of the high-order topological structures of nucleosomes and the comprehensive effects of regulatory factors, the research on the functional modulation mechanism of nucleosomes has encountered great challenges. The integration of computational and experimental approaches, the construction of physical modes for nucleosomes, and the application of deep learning techniques will provide promising opportunities for further exploration.
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Affiliation(s)
- Danfeng Shi
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen 518172, China
- School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Yuxin Huang
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen 518172, China
| | - Chen Bai
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen 518172, China
- Chenzhu (MoMeD) Biotechnology Co., Ltd., Hangzhou 310005, China
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40
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Kim TM, Lee RH, Kim MS, Lewis CA, Park C. ETV2/ER71, the key factor leading the paths to vascular regeneration and angiogenic reprogramming. Stem Cell Res Ther 2023; 14:41. [PMID: 36927793 PMCID: PMC10019431 DOI: 10.1186/s13287-023-03267-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 03/08/2023] [Indexed: 03/18/2023] Open
Abstract
Extensive efforts have been made to achieve vascular regeneration accompanying tissue repair for treating vascular dysfunction-associated diseases. Recent advancements in stem cell biology and cell reprogramming have opened unforeseen opportunities to promote angiogenesis in vivo and generate autologous endothelial cells (ECs) for clinical use. We have, for the first time, identified a unique endothelial-specific transcription factor, ETV2/ER71, and revealed its essential role in regulating endothelial cell generation and function, along with vascular regeneration and tissue repair. Furthermore, we and other groups have demonstrated its ability to directly reprogram terminally differentiated non-ECs into functional ECs, proposing ETV2/ER71 as an effective therapeutic target for vascular diseases. In this review, we discuss the up-to-date status of studies on ETV2/ER71, spanning from its molecular mechanism to vasculo-angiogenic role and direct cell reprogramming toward ECs. Furthermore, we discuss future directions to deploy the clinical potential of ETV2/ER71 as a novel and potent target for vascular disorders such as cardiovascular disease, neurovascular impairment and cancer.
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Affiliation(s)
- Tae Min Kim
- Graduate School of International Agricultural Technology and Institutes of Green-Bio Science and Technology, Seoul National University, 1447 Pyeongchang-daero, Pyeongchang, Gangwon-do, 25354, Republic of Korea.
| | - Ra Ham Lee
- Department of Molecular and Cellular Physiology, Louisiana State University Health Science Center, 1501 Kings Highway, Shreveport, LA, 71103, USA
| | - Min Seong Kim
- Department of Molecular and Cellular Physiology, Louisiana State University Health Science Center, 1501 Kings Highway, Shreveport, LA, 71103, USA
| | - Chloe A Lewis
- Department of Molecular and Cellular Physiology, Louisiana State University Health Science Center, 1501 Kings Highway, Shreveport, LA, 71103, USA
| | - Changwon Park
- Department of Molecular and Cellular Physiology, Louisiana State University Health Science Center, 1501 Kings Highway, Shreveport, LA, 71103, USA.
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41
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Păun O, Tan YX, Patel H, Strohbuecker S, Ghanate A, Cobolli-Gigli C, Llorian Sopena M, Gerontogianni L, Goldstone R, Ang SL, Guillemot F, Dias C. Pioneer factor ASCL1 cooperates with the mSWI/SNF complex at distal regulatory elements to regulate human neural differentiation. Genes Dev 2023; 37:218-242. [PMID: 36931659 PMCID: PMC10111863 DOI: 10.1101/gad.350269.122] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 02/28/2023] [Indexed: 03/19/2023]
Abstract
Pioneer transcription factors are thought to play pivotal roles in developmental processes by binding nucleosomal DNA to activate gene expression, though mechanisms through which pioneer transcription factors remodel chromatin remain unclear. Here, using single-cell transcriptomics, we show that endogenous expression of neurogenic transcription factor ASCL1, considered a classical pioneer factor, defines a transient population of progenitors in human neural differentiation. Testing ASCL1's pioneer function using a knockout model to define the unbound state, we found that endogenous expression of ASCL1 drives progenitor differentiation by cis-regulation both as a classical pioneer factor and as a nonpioneer remodeler, where ASCL1 binds permissive chromatin to induce chromatin conformation changes. ASCL1 interacts with BAF SWI/SNF chromatin remodeling complexes, primarily at targets where it acts as a nonpioneer factor, and we provide evidence for codependent DNA binding and remodeling at a subset of ASCL1 and SWI/SNF cotargets. Our findings provide new insights into ASCL1 function regulating activation of long-range regulatory elements in human neurogenesis and uncover a novel mechanism of its chromatin remodeling function codependent on partner ATPase activity.
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Affiliation(s)
- Oana Păun
- Neural Stem Cell Biology Laboratory, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Yu Xuan Tan
- Neural Stem Cell Biology Laboratory, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Harshil Patel
- Bioinformatics and Biostatistics Science and Technology Platform, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Stephanie Strohbuecker
- Bioinformatics and Biostatistics Science and Technology Platform, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Avinash Ghanate
- Bioinformatics and Biostatistics Science and Technology Platform, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Clementina Cobolli-Gigli
- Neural Stem Cell Biology Laboratory, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Miriam Llorian Sopena
- Bioinformatics and Biostatistics Science and Technology Platform, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Lina Gerontogianni
- Bioinformatics and Biostatistics Science and Technology Platform, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Robert Goldstone
- Bioinformatics and Biostatistics Science and Technology Platform, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Siew-Lan Ang
- Neural Stem Cell Biology Laboratory, the Francis Crick Institute, London NW1 1AT, United Kingdom
| | - François Guillemot
- Neural Stem Cell Biology Laboratory, the Francis Crick Institute, London NW1 1AT, United Kingdom;
| | - Cristina Dias
- Neural Stem Cell Biology Laboratory, the Francis Crick Institute, London NW1 1AT, United Kingdom;
- Medical and Molecular Genetics, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, King's College London, London SE1 9RT, United Kingdom
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42
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Kim S, Wysocka J. Deciphering the multi-scale, quantitative cis-regulatory code. Mol Cell 2023; 83:373-392. [PMID: 36693380 PMCID: PMC9898153 DOI: 10.1016/j.molcel.2022.12.032] [Citation(s) in RCA: 57] [Impact Index Per Article: 57.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/29/2022] [Accepted: 12/30/2022] [Indexed: 01/24/2023]
Abstract
Uncovering the cis-regulatory code that governs when and how much each gene is transcribed in a given genome and cellular state remains a central goal of biology. Here, we discuss major layers of regulation that influence how transcriptional outputs are encoded by DNA sequence and cellular context. We first discuss how transcription factors bind specific DNA sequences in a dosage-dependent and cooperative manner and then proceed to the cofactors that facilitate transcription factor function and mediate the activity of modular cis-regulatory elements such as enhancers, silencers, and promoters. We then consider the complex and poorly understood interplay of these diverse elements within regulatory landscapes and its relationships with chromatin states and nuclear organization. We propose that a mechanistically informed, quantitative model of transcriptional regulation that integrates these multiple regulatory layers will be the key to ultimately cracking the cis-regulatory code.
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Affiliation(s)
- Seungsoo Kim
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Joanna Wysocka
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA.
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43
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Guan R, Lian T, Zhou BR, Bai Y. Structural mechanism of LIN28B nucleosome targeting by OCT4 for pluripotency. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.03.522631. [PMID: 36789416 PMCID: PMC9928048 DOI: 10.1101/2023.01.03.522631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Pioneer transcription factors are essential for cell fate changes by targeting closed chromatin. OCT4 is a crucial pioneer factor that can induce cell reprogramming. However, the structural basis of how pioneer factors recognize the in vivo nucleosomal DNA targets is unknown. Here, we determine the high-resolution structures of the nucleosome containing human LIN28B DNA and its complexes with the OCT4 DNA binding region. Three OCT4s bind the pre-positioned nucleosome by recognizing non-canonical DNA motifs. Two use their POUS domains by forming extensive hydrogen bonds. The other uses the POUS-loop-POUHD region; POUHD serves as a wedge to unwrap ∼25 base pair DNA. Biochemical studies suggest that multiple OCT4s cooperatively open the H1-condensed nucleosome array containing the LIN28B nucleosome. Our study suggests a mechanism whereby OCT4s target the LIN28B nucleosome by forming multivalent interactions with nucleosomal motifs, unwrapping nucleosomal DNA, evicting H1, and cooperatively open closed chromatin to initiate cell reprogramming.
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Affiliation(s)
- Ruifang Guan
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.,These authors equally contributed to this work
| | - Tengfei Lian
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.,These authors equally contributed to this work
| | - Bing-Rui Zhou
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Yawen Bai
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.,Correspondence:
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44
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Colonnetta MM, Schedl P, Deshpande G. Germline/soma distinction in Drosophila embryos requires regulators of zygotic genome activation. eLife 2023; 12:78188. [PMID: 36598809 PMCID: PMC9812407 DOI: 10.7554/elife.78188] [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: 02/25/2022] [Accepted: 12/23/2022] [Indexed: 01/05/2023] Open
Abstract
In Drosophila melanogaster embryos, somatic versus germline identity is the first cell fate decision. Zygotic genome activation (ZGA) orchestrates regionalized gene expression, imparting specific identity on somatic cells. ZGA begins with a minor wave that commences at nuclear cycle (NC)8 under the guidance of chromatin accessibility factors (Zelda, CLAMP, GAF), followed by the major wave during NC14. By contrast, primordial germ cell (PGC) specification requires maternally deposited and posteriorly anchored germline determinants. This is accomplished by a centrosome coordinated release and sequestration of germ plasm during the precocious cellularization of PGCs in NC10. Here, we report a novel requirement for Zelda and CLAMP during the establishment of the germline/soma distinction. When their activity is compromised, PGC determinants are not properly sequestered, and specification is disrupted. Conversely, the spreading of PGC determinants from the posterior pole adversely influences transcription in the neighboring somatic nuclei. These reciprocal aberrations can be correlated with defects in centrosome duplication/separation that are known to induce inappropriate transmission of the germ plasm. Interestingly, consistent with the ability of bone morphogenetic protein (BMP) signaling to influence specification of embryonic PGCs, reduction in the transcript levels of a BMP family ligand, decapentaplegic (dpp), is exacerbated at the posterior pole.
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Affiliation(s)
- Megan M Colonnetta
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - Paul Schedl
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - Girish Deshpande
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
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45
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Yu C, Li X, Zhao Y, Hu Y. The role of FOXA family transcription factors in glucolipid metabolism and NAFLD. Front Endocrinol (Lausanne) 2023; 14:1081500. [PMID: 36798663 PMCID: PMC9927216 DOI: 10.3389/fendo.2023.1081500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 01/17/2023] [Indexed: 02/04/2023] Open
Abstract
Abnormal glucose metabolism and lipid metabolism are common pathological processes in many metabolic diseases, such as nonalcoholic fatty liver disease (NAFLD). Many studies have shown that the forkhead box (FOX) protein subfamily FOXA has a role in regulating glucolipid metabolism and is closely related to hepatic steatosis and NAFLD. FOXA exhibits a wide range of functions ranging from the initiation steps of metabolism such as the development of the corresponding metabolic organs and the differentiation of cells, to multiple pathways of glucolipid metabolism, to end-of-life problems of metabolism such as age-related obesity. The purpose of this article is to review and discuss the currently known targets and signal transduction pathways of FOXA in glucolipid metabolism. To provide more experimental evidence and basis for further research and clinical application of FOXA in the regulation of glucolipid metabolism and the prevention and treatment of NAFLD.
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Affiliation(s)
- Chuchu Yu
- Key Laboratory of Liver and Kidney Diseases (Ministry of Education), Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Institute of Liver Diseases, Shuguang Hospital Affifiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xiaojing Li
- Key Laboratory of Liver and Kidney Diseases (Ministry of Education), Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Institute of Liver Diseases, Shuguang Hospital Affifiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yu Zhao
- Key Laboratory of Liver and Kidney Diseases (Ministry of Education), Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Institute of Liver Diseases, Shuguang Hospital Affifiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
- *Correspondence: Yu Zhao, ; Yiyang Hu,
| | - Yiyang Hu
- Key Laboratory of Liver and Kidney Diseases (Ministry of Education), Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Institute of Liver Diseases, Shuguang Hospital Affifiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Institute of Clinical Pharmacology, Shuguang Hospital Affifiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
- *Correspondence: Yu Zhao, ; Yiyang Hu,
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46
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Alatawneh R, Salomon Y, Eshel R, Orenstein Y, Birnbaum RY. Deciphering transcription factors and their corresponding regulatory elements during inhibitory interneuron differentiation using deep neural networks. Front Cell Dev Biol 2023; 11:1034604. [PMID: 36891511 PMCID: PMC9986276 DOI: 10.3389/fcell.2023.1034604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 01/23/2023] [Indexed: 02/22/2023] Open
Abstract
During neurogenesis, the generation and differentiation of neuronal progenitors into inhibitory gamma-aminobutyric acid-containing interneurons is dependent on the combinatorial activity of transcription factors (TFs) and their corresponding regulatory elements (REs). However, the roles of neuronal TFs and their target REs in inhibitory interneuron progenitors are not fully elucidated. Here, we developed a deep-learning-based framework to identify enriched TF motifs in gene REs (eMotif-RE), such as poised/repressed enhancers and putative silencers. Using epigenetic datasets (e.g., ATAC-seq and H3K27ac/me3 ChIP-seq) from cultured interneuron-like progenitors, we distinguished between active enhancer sequences (open chromatin with H3K27ac) and non-active enhancer sequences (open chromatin without H3K27ac). Using our eMotif-RE framework, we discovered enriched motifs of TFs such as ASCL1, SOX4, and SOX11 in the active enhancer set suggesting a cooperativity function for ASCL1 and SOX4/11 in active enhancers of neuronal progenitors. In addition, we found enriched ZEB1 and CTCF motifs in the non-active set. Using an in vivo enhancer assay, we showed that most of the tested putative REs from the non-active enhancer set have no enhancer activity. Two of the eight REs (25%) showed function as poised enhancers in the neuronal system. Moreover, mutated REs for ZEB1 and CTCF motifs increased their in vivo activity as enhancers indicating a repressive effect of ZEB1 and CTCF on these REs that likely function as repressed enhancers or silencers. Overall, our work integrates a novel framework based on deep learning together with a functional assay that elucidated novel functions of TFs and their corresponding REs. Our approach can be applied to better understand gene regulation not only in inhibitory interneuron differentiation but in other tissue and cell types.
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Affiliation(s)
- Rawan Alatawneh
- Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Yahel Salomon
- School of Electrical and Computer Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Reut Eshel
- Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Yaron Orenstein
- School of Electrical and Computer Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Department of Computer Science, Bar-Ilan University, Ramat Gan, Israel.,The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Ramon Y Birnbaum
- Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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47
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Frederick MA, Williamson KE, Fernandez Garcia M, Ferretti MB, McCarthy RL, Donahue G, Luzete Monteiro E, Takenaka N, Reynaga J, Kadoch C, Zaret KS. A pioneer factor locally opens compacted chromatin to enable targeted ATP-dependent nucleosome remodeling. Nat Struct Mol Biol 2023; 30:31-37. [PMID: 36536103 PMCID: PMC10004348 DOI: 10.1038/s41594-022-00886-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 11/03/2022] [Indexed: 12/24/2022]
Abstract
To determine how different pioneer transcription factors form a targeted, accessible nucleosome within compacted chromatin and collaborate with an ATP-dependent chromatin remodeler, we generated nucleosome arrays in vitro with a central nucleosome containing binding sites for the hematopoietic E-Twenty Six (ETS) factor PU.1 and Basic Leucine Zipper (bZIP) factors C/EBPα and C/EBPβ. Our long-read sequencing reveals that each factor can expose a targeted nucleosome on linker histone-compacted arrays, but with different nuclease sensitivity patterns. The DNA binding domain of PU.1 binds mononucleosomes, but requires an additional intrinsically disordered domain to bind and open compacted chromatin. The canonical mammalian SWI/SNF (cBAF) remodeler was unable to act upon two forms of locally open chromatin unless cBAF was enabled by a separate transactivation domain of PU.1. cBAF potentiates the PU.1 DNA binding domain to weakly open chromatin in the absence of the PU.1 disordered domain. Our findings reveal a hierarchy by which chromatin is opened and show that pioneer factors can provide specificity for action by nucleosome remodelers.
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Affiliation(s)
- Megan A Frederick
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kaylyn E Williamson
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Meilin Fernandez Garcia
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Max B Ferretti
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ryan L McCarthy
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Greg Donahue
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Edgar Luzete Monteiro
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Naomi Takenaka
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Janice Reynaga
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Cigall Kadoch
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Department Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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48
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EKLF/Klf1 regulates erythroid transcription by its pioneering activity and selective control of RNA Pol II pause-release. Cell Rep 2022; 41:111830. [PMID: 36543143 PMCID: PMC9879271 DOI: 10.1016/j.celrep.2022.111830] [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: 08/18/2022] [Revised: 10/06/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
EKLF/Klf1 is a zinc-finger transcription activator essential for erythroid lineage commitment and terminal differentiation. Using ChIP-seq, we investigate EKLF DNA binding and transcription activation mechanisms during mouse embryonic erythropoiesis. We utilize the Nan/+ mouse that expresses the EKLF-E339D (Nan) variant mutated in its conserved zinc-finger region and address the mechanism of hypomorphic and neomorphic changes in downstream gene expression. First, we show that Nan-EKLF limits normal EKLF binding to a subset of its sites. Second, we find that ectopic binding of Nan-EKLF occurs largely at enhancers and activates transcription through pioneering activity. Third, we find that for a subset of ectopic targets, gene activation is achieved in Nan/+ only by Nan-EKLF binding to distal enhancers, leading to RNA polymerase II pause-release. These results have general applicability to understanding how a DNA binding variant factor confers dominant disruptive effects on downstream gene expression even in the presence of its normal counterpart.
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49
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Veverka P, Brom T, Janovič T, Stojaspal M, Pinkas M, Nováček J, Hofr C. Electron microscopy reveals toroidal shape of master neuronal cell differentiator REST - RE1-silencing transcription factor. Comput Struct Biotechnol J 2022; 21:731-741. [PMID: 36698979 PMCID: PMC9860152 DOI: 10.1016/j.csbj.2022.12.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/15/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022] Open
Abstract
The RE1-Silencing Transcription factor (REST) is essential for neuronal differentiation. Here, we report the first 18.5-angstrom electron microscopy structure of human REST. The refined electron map suggests that REST forms a torus that can accommodate DNA double-helix in the central hole. Additionally, we quantitatively described REST binding to the canonical DNA sequence of the neuron-restrictive silencer element. We developed protocols for the expression and purification of full-length REST and the shortened variant REST-N62 produced by alternative splicing. We tested the mutual interaction of full-length REST and the splicing variant REST-N62. Revealed structure-function relationships of master neuronal repressor REST will allow finding new biological ways of prevention and treatment of neurodegenerative disorders and diseases.
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Key Words
- CD, circular dichroism
- CoIP, coimmunoprecipitation
- DLS, dynamic light scattering
- Differentiation
- EM
- EM, electron microscopy
- Electron microscopy
- IDRs, intrinsically disordered regions
- NRSE, neuron-restrictive silencer element
- NRSF
- NRSF, neuron-restrictive silencer factor
- Neuron-restrictive silencer factor
- Neuronal
- PCNA, proliferating cell nuclear antigen
- RD1/2, repressor domain 1/2
- RE1, repressor element-1
- RE1-silencing transcription factor
- REST
- REST, RE1-silencing transcription factor
- REST-FL, full-length REST
- REST-N62
- REST-N62, splicing isoform of REST, also known as REST4 or REST4-S3
- REST4
- ZF, zinc finger
- aa, amino acid(s)
- bp, base pair(s)
- kDa, kilodaltons
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Affiliation(s)
- Pavel Veverka
- LifeB, FGP – NCBR, Faculty of Science, Masaryk University, Kamenice 753/5, Brno 625 00, Czech Republic
- Institute of Biophysics of the Czech Academy of Sciences, Scientific Incubator, Královopolská 135, Brno 612 65, Czech Republic
| | - Tomáš Brom
- LifeB, FGP – NCBR, Faculty of Science, Masaryk University, Kamenice 753/5, Brno 625 00, Czech Republic
| | - Tomáš Janovič
- LifeB, FGP – NCBR, Faculty of Science, Masaryk University, Kamenice 753/5, Brno 625 00, Czech Republic
| | - Martin Stojaspal
- LifeB, FGP – NCBR, Faculty of Science, Masaryk University, Kamenice 753/5, Brno 625 00, Czech Republic
- Institute of Biophysics of the Czech Academy of Sciences, Scientific Incubator, Královopolská 135, Brno 612 65, Czech Republic
| | | | - Jiří Nováček
- CEITEC, Masaryk University, Brno, Czech Republic
| | - Ctirad Hofr
- LifeB, FGP – NCBR, Faculty of Science, Masaryk University, Kamenice 753/5, Brno 625 00, Czech Republic
- Corresponding author.
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50
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Larcombe MR, Hsu S, Polo JM, Knaupp AS. Indirect Mechanisms of Transcription Factor-Mediated Gene Regulation during Cell Fate Changes. ADVANCED GENETICS (HOBOKEN, N.J.) 2022; 3:2200015. [PMID: 36911290 PMCID: PMC9993476 DOI: 10.1002/ggn2.202200015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Indexed: 06/18/2023]
Abstract
Transcription factors (TFs) are the master regulators of cellular identity, capable of driving cell fate transitions including differentiations, reprogramming, and transdifferentiations. Pioneer TFs recognize partial motifs exposed on nucleosomal DNA, allowing for TF-mediated activation of repressed chromatin. Moreover, there is evidence suggesting that certain TFs can repress actively expressed genes either directly through interactions with accessible regulatory elements or indirectly through mechanisms that impact the expression, activity, or localization of other regulatory factors. Recent evidence suggests that during reprogramming, the reprogramming TFs initiate opening of chromatin regions rich in somatic TF motifs that are inaccessible in the initial and final cellular states. It is postulated that analogous to a sponge, these transiently accessible regions "soak up" somatic TFs, hence lowering the initial barriers to cell fate changes. This indirect TF-mediated gene regulation event, which is aptly named the "sponge effect," may play an essential role in the silencing of the somatic transcriptional network during different cellular conversions.
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Affiliation(s)
- Michael R. Larcombe
- Department of Anatomy and Developmental BiologyMonash UniversityClaytonVictoria3168Australia
- Development and Stem Cells ProgramMonash Biomedicine Discovery InstituteClaytonVictoria3168Australia
- Australian Regenerative Medicine InstituteMonash UniversityClaytonVictoria3168Australia
| | - Sheng Hsu
- Department of Anatomy and Developmental BiologyMonash UniversityClaytonVictoria3168Australia
- Development and Stem Cells ProgramMonash Biomedicine Discovery InstituteClaytonVictoria3168Australia
- Australian Regenerative Medicine InstituteMonash UniversityClaytonVictoria3168Australia
| | - Jose M. Polo
- Department of Anatomy and Developmental BiologyMonash UniversityClaytonVictoria3168Australia
- Development and Stem Cells ProgramMonash Biomedicine Discovery InstituteClaytonVictoria3168Australia
- Australian Regenerative Medicine InstituteMonash UniversityClaytonVictoria3168Australia
- South Australian Immunogenomics Cancer Institute, Faculty of Health and Medical SciencesUniversity of AdelaideAdelaideSouth Australia5005Australia
- Adelaide Centre for Epigenetics, Faculty of Health and Medical SciencesUniversity of AdelaideAdelaideSouth Australia5005Australia
| | - Anja S. Knaupp
- Department of Anatomy and Developmental BiologyMonash UniversityClaytonVictoria3168Australia
- Development and Stem Cells ProgramMonash Biomedicine Discovery InstituteClaytonVictoria3168Australia
- Australian Regenerative Medicine InstituteMonash UniversityClaytonVictoria3168Australia
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