1
|
Becker PB. Cell-free genomics: transcription factor interactions in reconstituted naïve embryonic chromatin. Biochem Soc Trans 2024; 52:423-429. [PMID: 38329186 DOI: 10.1042/bst20230878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/26/2024] [Accepted: 01/30/2024] [Indexed: 02/09/2024]
Abstract
Extracts from Drosophila preblastoderm embryos (DREX) form the basis of a powerful in vitro chromatin reconstitution system that assembles entire genomes into complex chromatin with physiological nucleosome spacing and polymer condensation. As the zygotic genome has not yet been activated in preblastoderm embryos, the reconstitution extract lacks endogenous transcription factors (TFs) and the RNA polymerase machinery. At the same time, it contains high levels of ATP-dependent nucleosome sliding enzymes that render the reconstituted chromatin dynamic. The naïve chromatin can be used to determine the intrinsic DNA binding properties of exogenous, usually recombinant TFs (or DNA binding proteins in general) in a complex chromatin context. Recent applications of the system include the description of cooperation and competition of Drosophila pioneer TFs for composite binding sites, and the characterization of nucleosome interactions of mammalian pioneer TFs in the heterologous system.
Collapse
Affiliation(s)
- Peter B Becker
- Biomedical Center, Molecular Biology Division, Faculty of Medicine, LMU, Munich, Germany
| |
Collapse
|
2
|
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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
3
|
Ooi SK, Sato S, Tomomori-Sato C, Zhang Y, Wen Z, Banks CAS, Washburn MP, Unruh JR, Florens L, Conaway RC, Conaway JW. Multiple roles for PARP1 in ALC1-dependent nucleosome remodeling. Proc Natl Acad Sci U S A 2021; 118:e2107277118. [PMID: 34465625 DOI: 10.1073/pnas.2107277118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The SNF2 family ATPase Amplified in Liver Cancer 1 (ALC1) is the only chromatin remodeling enzyme with a poly(ADP-ribose) (PAR) binding macrodomain. ALC1 functions together with poly(ADP-ribose) polymerase PARP1 to remodel nucleosomes. Activation of ALC1 cryptic ATPase activity and the subsequent nucleosome remodeling requires binding of its macrodomain to PAR chains synthesized by PARP1 and NAD+ A key question is whether PARP1 has a role(s) in ALC1-dependent nucleosome remodeling beyond simply synthesizing the PAR chains needed to activate the ALC1 ATPase. Here, we identify PARP1 separation-of-function mutants that activate ALC1 ATPase but do not support nucleosome remodeling by ALC1. Investigation of these mutants has revealed multiple functions for PARP1 in ALC1-dependent nucleosome remodeling and provides insights into its multifaceted role in chromatin remodeling.
Collapse
|
4
|
Chen H, Liang H. A High-Resolution Map of Human Enhancer RNA Loci Characterizes Super-enhancer Activities in Cancer. Cancer Cell 2020; 38:701-715.e5. [PMID: 33007258 PMCID: PMC7658066 DOI: 10.1016/j.ccell.2020.08.020] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 07/21/2020] [Accepted: 08/28/2020] [Indexed: 12/20/2022]
Abstract
Although enhancers play critical roles in cancer, quantifying enhancer activities in clinical samples remains challenging, especially for super-enhancers. Enhancer activities can be inferred from enhancer RNA (eRNA) signals, which requires enhancer transcription loci definition. Only a small proportion of human eRNA loci has been precisely identified, limiting investigations of enhancer-mediated oncogenic mechanisms. Here, we characterize super-enhancer regions using aggregated RNA sequencing (RNA-seq) data from large cohorts. Super-enhancers usually contain discrete loci featuring sharp eRNA expression peaks. We identify >300,000 eRNA loci in ∼377 Mb super-enhancer regions that are regulated by evolutionarily conserved, well-positioned nucleosomes and are frequently dysregulated in cancer. The eRNAs provide explanatory power for cancer phenotypes beyond that provided by mRNA expression through resolving intratumoral heterogeneity with enhancer cell-type specificity. Our study provides a high-resolution map of eRNA loci through which super-enhancer activities can be quantified by RNA-seq and a user-friendly data portal, enabling a broad range of biomedical investigations.
Collapse
Affiliation(s)
- Han Chen
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Han Liang
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| |
Collapse
|
5
|
Kim SA, Zhu J, Yennawar N, Eek P, Tan S. Crystal Structure of the LSD1/CoREST Histone Demethylase Bound to Its Nucleosome Substrate. Mol Cell 2020; 78:903-914.e4. [PMID: 32396821 DOI: 10.1016/j.molcel.2020.04.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 03/02/2020] [Accepted: 04/15/2020] [Indexed: 12/18/2022]
Abstract
LSD1 (lysine specific demethylase; also known as KDM1A), the first histone demethylase discovered, regulates cell-fate determination and is overexpressed in multiple cancers. LSD1 demethylates histone H3 Lys4, an epigenetic mark for active genes, but requires the CoREST repressor to act on nucleosome substrates. To understand how an accessory subunit (CoREST) enables a chromatin enzyme (LSD1) to function on a nucleosome and not just histones, we have determined the crystal structure of the LSD1/CoREST complex bound to a 191-bp nucleosome. We find that the LSD1 catalytic domain binds extranucleosomal DNA and is unexpectedly positioned 100 Å away from the nucleosome core. CoREST makes critical contacts with both histone and DNA components of the nucleosome, explaining its essential function in demethylating nucleosome substrates. Our studies also show that the LSD1(K661A) frequently used as a catalytically inactive mutant in vivo (based on in vitro peptide studies) actually retains substantial H3K4 demethylase activity on nucleosome substrates.
Collapse
Affiliation(s)
- Sang-Ah Kim
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jiang Zhu
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA
| | - Neela Yennawar
- Huck Institutes of the Life Sciences, 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
| | - Song Tan
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA.
| |
Collapse
|
6
|
Fernandez Garcia M, Moore CD, Schulz KN, Alberto O, Donague G, Harrison MM, Zhu H, Zaret KS. Structural Features of Transcription Factors Associating with Nucleosome Binding. Mol Cell 2019; 75:921-932.e6. [PMID: 31303471 DOI: 10.1016/j.molcel.2019.06.009] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 05/01/2019] [Accepted: 06/07/2019] [Indexed: 10/26/2022]
Abstract
Fate-changing transcription factors (TFs) scan chromatin to initiate new genetic programs during cell differentiation and reprogramming. Yet the protein structure domains that allow TFs to target nucleosomal DNA remain unexplored. We screened diverse TFs for binding to nucleosomes containing motif-enriched sequences targeted by pioneer factors in vivo. FOXA1, OCT4, ASCL1/E12α, PU1, CEBPα, and ZELDA display a range of nucleosome binding affinities that correlate with their cell reprogramming potential. We further screened 593 full-length human TFs on protein microarrays against different nucleosome sequences, followed by confirmation in solution, to distinguish among factors that bound nucleosomes, such as the neuronal AP-2α/β/γ, versus factors that only bound free DNA. Structural comparisons of DNA binding domains revealed that efficient nucleosome binders use short anchoring α helices to bind DNA, whereas weak nucleosome binders use unstructured regions and/or β sheets. Thus, specific modes of DNA interaction allow nucleosome scanning that confers pioneer activity to transcription factors.
Collapse
Affiliation(s)
- Meilin Fernandez Garcia
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-5157, USA
| | - Cedric D Moore
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Katharine N Schulz
- Department of Biomolecular Chemistry, School of Medicine and Public Health, University of Wisconsin Madison, Madison, WI 53706, USA
| | - Oscar Alberto
- Institute for Regenerative Medicine, Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-5157, USA
| | - Greg Donague
- Institute for Regenerative Medicine, Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-5157, USA
| | - Melissa M Harrison
- Department of Biomolecular Chemistry, School of Medicine and Public Health, University of Wisconsin Madison, Madison, WI 53706, USA
| | - Heng Zhu
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-5157, USA.
| |
Collapse
|
7
|
Takizawa Y, Tanaka H, Machida S, Koyama M, Maehara K, Ohkawa Y, Wade PA, Wolf M, Kurumizaka H. Cryo-EM structure of the nucleosome containing the ALB1 enhancer DNA sequence. Open Biol 2019; 8:rsob.170255. [PMID: 29563192 PMCID: PMC5881032 DOI: 10.1098/rsob.170255] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 02/23/2018] [Indexed: 02/01/2023] Open
Abstract
Pioneer transcription factors specifically target their recognition DNA sequences within nucleosomes. FoxA is the pioneer transcription factor that binds to the ALB1 gene enhancer in liver precursor cells, and is required for liver differentiation in embryos. The ALB1 enhancer DNA sequence is reportedly incorporated into nucleosomes in cells, although the nucleosome structure containing the targeting sites for FoxA has not been clarified yet. In this study, we determined the nucleosome structure containing the ALB1 enhancer (N1) sequence, by cryogenic electron microscopy at 4.0 Å resolution. The nucleosome structure with the ALB1 enhancer DNA is not significantly different from the previously reported nucleosome structure with the Widom 601 DNA. Interestingly, in the nucleosomes, the ALB1 enhancer DNA contains local flexible regions, as compared to the Widom 601 DNA. Consistently, DNaseI treatments revealed that, in the nucleosome, the ALB1 enhancer (N1) DNA is more accessible than the Widom 601 sequence. The histones also associated less strongly with the ALB1 enhancer (N1) DNA than the Widom 601 DNA in the nucleosome. Therefore, the local histone–DNA contacts may be responsible for the enhanced DNA accessibility in the nucleosome with the ALB1 enhancer DNA.
Collapse
Affiliation(s)
- Yoshimasa Takizawa
- Molecular Cryo-Electron Microscopy Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami, Okinawa 904-0495, Japan
| | - Hiroki Tanaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Shinichi Machida
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Masako Koyama
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Kazumitsu Maehara
- Division of Transcriptomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi, Fukuoka 812-0054, Japan
| | - Yasuyuki Ohkawa
- Division of Transcriptomics, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi, Fukuoka 812-0054, Japan
| | - Paul A Wade
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Matthias Wolf
- Molecular Cryo-Electron Microscopy Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami, Okinawa 904-0495, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan .,Institute for Medical-oriented Structural Biology, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
| |
Collapse
|
8
|
Qin S, Min J. Structure and function of the nucleosome-binding PWWP domain. Trends Biochem Sci 2014; 39:536-47. [PMID: 25277115 DOI: 10.1016/j.tibs.2014.09.001] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 08/26/2014] [Accepted: 09/08/2014] [Indexed: 12/11/2022]
Abstract
PWWP domain-containing proteins are often involved in chromatin-associated biological processes, such as transcriptional regulation and DNA repair, and recent studies have shown that the PWWP domain specifies chromatin localization. Mutations in the PWWP domain, a 100-150 amino acid motif, have been linked to various human diseases, emphasizing its importance. Structural studies reveal that PWWP domains possess a conserved aromatic cage for histone methyl-lysine recognition, and synergistically bind both histone and DNA, which contributes to their nucleosome-binding ability and chromatin localization. Furthermore, the PWWP domain often cooperates with other histone and DNA 'reader' or 'modifier' domains to evoke crosstalk between various epigenetic marks. Here, we discuss these recent advances in understanding the structure and function of the PWWP domain.
Collapse
Affiliation(s)
- Su Qin
- Structural Genomics Consortium, University of Toronto, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Jinrong Min
- Structural Genomics Consortium, University of Toronto, 101 College Street, Toronto, Ontario M5G 1L7, Canada; Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
| |
Collapse
|
9
|
Gerhold CB, Gasser SM. INO80 and SWR complexes: relating structure to function in chromatin remodeling. Trends Cell Biol 2014; 24:619-31. [PMID: 25088669 DOI: 10.1016/j.tcb.2014.06.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 06/23/2014] [Accepted: 06/24/2014] [Indexed: 02/04/2023]
Abstract
Virtually all DNA-dependent processes require selective and controlled access to the DNA sequence. Governing this access are sophisticated molecular machines, nucleosome remodelers, which regulate the composition and structure of chromatin, allowing conversion from open to closed states. In most cases these multisubunit remodelers operate in concert to organize chromatin structure by depositing, moving, evicting, or selectively altering nucleosomes in an ATP-dependent manner. Despite sharing a conserved domain architecture, chromatin remodelers differ significantly in how they bind to their nucleosomal substrates. Recent structural studies link specific interactions between nucleosomes and remodelers to the diverse tasks they carry out. We review here insights into the modular organization of the INO80 family of nucleosome remodelers. Understanding their structural diversity will help to shed light on how these related ATPases modify their nucleosomal substrates.
Collapse
Affiliation(s)
- Christian B Gerhold
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Susan M Gasser
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland; Faculty of Natural Sciences, University of Basel, Basel, Switzerland.
| |
Collapse
|