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Batra SS, Cabrera A, Spence JP, Goell J, Anand SS, Hilton IB, Song YS. Predicting the effect of CRISPR-Cas9-based epigenome editing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.10.03.560674. [PMID: 37873127 PMCID: PMC10592942 DOI: 10.1101/2023.10.03.560674] [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
Epigenetic regulation orchestrates mammalian transcription, but functional links between them remain elusive. To tackle this problem, we use epigenomic and transcriptomic data from 13 ENCODE cell types to train machine learning models to predict gene expression from histone post-translational modifications (PTMs), achieving transcriptome-wide correlations of ∼ 0.70 - 0.79 for most cell types. Our models recapitulate known associations between histone PTMs and expression patterns, including predicting that acetylation of histone subunit H3 lysine residue 27 (H3K27ac) near the transcription start site (TSS) significantly increases expression levels. To validate this prediction experimentally and investigate how natural vs. engineered deposition of H3K27ac might differentially affect expression, we apply the synthetic dCas9-p300 histone acetyltransferase system to 8 genes in the HEK293T cell line and to 5 genes in the K562 cell line. Further, to facilitate model building, we perform MNase-seq to map genome-wide nucleosome occupancy levels in HEK293T. We observe that our models perform well in accurately ranking relative fold-changes among genes in response to the dCas9-p300 system; however, their ability to rank fold-changes within individual genes is noticeably diminished compared to predicting expression across cell types from their native epigenetic signatures. Our findings highlight the need for more comprehensive genome-scale epigenome editing datasets, better understanding of the actual modifications made by epigenome editing tools, and improved causal models that transfer better from endogenous cellular measurements to perturbation experiments. Together these improvements would facilitate the ability to understand and predictably control the dynamic human epigenome with consequences for human health.
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2
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Alcantar MA, English MA, Valeri JA, Collins JJ. A high-throughput synthetic biology approach for studying combinatorial chromatin-based transcriptional regulation. Mol Cell 2024; 84:2382-2396.e9. [PMID: 38906116 DOI: 10.1016/j.molcel.2024.05.025] [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: 06/05/2023] [Revised: 04/11/2024] [Accepted: 05/24/2024] [Indexed: 06/23/2024]
Abstract
The construction of synthetic gene circuits requires the rational combination of multiple regulatory components, but predicting their behavior can be challenging due to poorly understood component interactions and unexpected emergent behaviors. In eukaryotes, chromatin regulators (CRs) are essential regulatory components that orchestrate gene expression. Here, we develop a screening platform to investigate the impact of CR pairs on transcriptional activity in yeast. We construct a combinatorial library consisting of over 1,900 CR pairs and use a high-throughput workflow to characterize the impact of CR co-recruitment on gene expression. We recapitulate known interactions and discover several instances of CR pairs with emergent behaviors. We also demonstrate that supervised machine learning models trained with low-dimensional amino acid embeddings accurately predict the impact of CR co-recruitment on transcriptional activity. This work introduces a scalable platform and machine learning approach that can be used to study how networks of regulatory components impact gene expression.
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Affiliation(s)
- Miguel A Alcantar
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Institute for Medical Engineering and Science, MIT, Cambridge, MA 02139, USA
| | - Max A English
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Institute for Medical Engineering and Science, MIT, Cambridge, MA 02139, USA
| | - Jacqueline A Valeri
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Institute for Medical Engineering and Science, MIT, Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - James J Collins
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Institute for Medical Engineering and Science, MIT, Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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3
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Liu HN, Wang XY, Zou Y, Wu WB, Lin Y, Ji BY, Wang TY. Synthetic enhancers including TFREs improve transgene expression in CHO cells. Heliyon 2024; 10:e26901. [PMID: 38468921 PMCID: PMC10926067 DOI: 10.1016/j.heliyon.2024.e26901] [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: 12/27/2023] [Revised: 02/12/2024] [Accepted: 02/21/2024] [Indexed: 03/13/2024] Open
Abstract
The human cytomegalovirus major immediate early gene (CMV) promoter is currently the most preferred promoter for recombinant therapeutic proteins (RTPs) production in CHO cells. To enhance the production of RTPs, five synthetic enhancers including multiple transcription factor regulatory elements (TFREs) were evaluated to enhance recombinant protein level in transient and stably transfected CHO cells. Compared with the control, four elements can enhance the report genes expression under both two transfected states. Further, the function of these four enhancers on human serum albumin (HSA) were investigated. We found that the transient expression can increase by up to 1.5 times, and the stably expression can maximum increase by up to 2.14 times. The enhancement of transgene expression was caused by the boost of their corresponding mRNA levels. Transcriptomics analysis was performed and found that transcriptional activation and cell cycle regulation genes were involved. In conclusion, optimization of enhancers in the CMV promoter could increase the production yield of transgene in transfected CHO cells, which has significance for developing high-yield CHO cell expression system.
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Affiliation(s)
- Hui-Ning Liu
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang 453003, China
- SanQuan College of Xinxiang Medical University, Xinxiang 453003, China
| | - Xiao-Yin Wang
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang 453003, China
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Xinxiang Medical University, Xinxiang 453003, China
| | - Ying Zou
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang 453003, China
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Xinxiang Medical University, Xinxiang 453003, China
| | - Wen-Bao Wu
- Shanghai Immunocan Biotech Co., LTD, Shanghai 200000, China
| | - Yan Lin
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang 453003, China
| | - Bo-Yu Ji
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang 453003, China
| | - Tian-Yun Wang
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang 453003, China
- Department of Biochemistry and Molecular Biology, School of Basic Medicine, Xinxiang Medical University, Xinxiang 453003, China
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4
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Yagci ZB, Kelkar GR, Johnson TJ, Sen D, Keung AJ. Designing Epigenome Editors: Considerations of Biochemical and Locus Specificities. Methods Mol Biol 2024; 2842:23-55. [PMID: 39012589 DOI: 10.1007/978-1-0716-4051-7_2] [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] [Indexed: 07/17/2024]
Abstract
The advent of locus-specific protein recruitment technologies has enabled a new class of studies in chromatin biology. Epigenome editors (EEs) enable biochemical modifications of chromatin at almost any specific endogenous locus. Their locus-specificity unlocks unique information including the functional roles of distinct modifications at specific genomic loci. Given the growing interest in using these tools for biological and translational studies, there are many specific design considerations depending on the scientific question or clinical need. Here, we present and discuss important design considerations and challenges regarding the biochemical and locus specificities of epigenome editors. These include how to: account for the complex biochemical diversity of chromatin; control for potential interdependency of epigenome editors and their resultant modifications; avoid sequestration effects; quantify the locus specificity of epigenome editors; and improve locus-specificity by considering concentration, affinity, avidity, and sequestration effects.
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Affiliation(s)
- Z Begum Yagci
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Gautami R Kelkar
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Tyler J Johnson
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Dilara Sen
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Albert J Keung
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA.
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5
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Cabrera A, Edelstein HI, Glykofrydis F, Love KS, Palacios S, Tycko J, Zhang M, Lensch S, Shields CE, Livingston M, Weiss R, Zhao H, Haynes KA, Morsut L, Chen YY, Khalil AS, Wong WW, Collins JJ, Rosser SJ, Polizzi K, Elowitz MB, Fussenegger M, Hilton IB, Leonard JN, Bintu L, Galloway KE, Deans TL. The sound of silence: Transgene silencing in mammalian cell engineering. Cell Syst 2022; 13:950-973. [PMID: 36549273 PMCID: PMC9880859 DOI: 10.1016/j.cels.2022.11.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/22/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022]
Abstract
To elucidate principles operating in native biological systems and to develop novel biotechnologies, synthetic biology aims to build and integrate synthetic gene circuits within native transcriptional networks. The utility of synthetic gene circuits for cell engineering relies on the ability to control the expression of all constituent transgene components. Transgene silencing, defined as the loss of expression over time, persists as an obstacle for engineering primary cells and stem cells with transgenic cargos. In this review, we highlight the challenge that transgene silencing poses to the robust engineering of mammalian cells, outline potential molecular mechanisms of silencing, and present approaches for preventing transgene silencing. We conclude with a perspective identifying future research directions for improving the performance of synthetic gene circuits.
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Affiliation(s)
- Alan Cabrera
- Department of Bioengineering, Rice University, Houston, TX 77005, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hailey I Edelstein
- Center for Synthetic Biology, Northwestern University, Evanston, IL 60208, USA; The Eli and Edythe Broad CIRM Center, Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Fokion Glykofrydis
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA 90033-9080, USA
| | - Kasey S Love
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sebastian Palacios
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Josh Tycko
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Meng Zhang
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, Urbana, IL 61801, USA
| | - Sarah Lensch
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Cara E Shields
- Wallace H. Coulter Department of Biomedical Engineering, Emory University, Atlanta, GA 30322, USA
| | - Mark Livingston
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA
| | - Ron Weiss
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Champaign, Urbana, IL 61801, USA
| | - Karmella A Haynes
- Wallace H. Coulter Department of Biomedical Engineering, Emory University, Atlanta, GA 30322, USA
| | - Leonardo Morsut
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA 90033-9080, USA
| | - Yvonne Y Chen
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA; Parker Institute for Cancer Immunotherapy Center at UCLA, Los Angeles, CA 90095, USA
| | - Ahmad S Khalil
- Biological Design Center and Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Wilson W Wong
- Biological Design Center and Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - James J Collins
- Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, Los Angeles, CA 90033-9080, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA; Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Harvard-MIT Program in Health Sciences and Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA
| | - Susan J Rosser
- School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Karen Polizzi
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, UK; Imperial College Centre for Synthetic Biology, South Kensington Campus, London, UK
| | - Michael B Elowitz
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Howard Hughes Medical Institute, California Institute of Technology, Pasadena, CA 91125, USA
| | - Martin Fussenegger
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, Basel 4058, Switzerland; Faculty of Science, University of Basel, Mattenstrasse 26, Basel 4058, Switzerland
| | - Isaac B Hilton
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
| | - Joshua N Leonard
- Center for Synthetic Biology, Northwestern University, Evanston, IL 60208, USA; The Eli and Edythe Broad CIRM Center, Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Lacramioara Bintu
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Kate E Galloway
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Tara L Deans
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA.
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6
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The Spatial Organization of Bacterial Transcriptional Regulatory Networks. Microorganisms 2022; 10:microorganisms10122366. [PMID: 36557619 PMCID: PMC9787925 DOI: 10.3390/microorganisms10122366] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/18/2022] [Accepted: 11/28/2022] [Indexed: 12/02/2022] Open
Abstract
The transcriptional regulatory network (TRN) is the central pivot of a prokaryotic organism to receive, process and respond to internal and external environmental information. However, little is known about its spatial organization so far. In recent years, chromatin interaction data of bacteria such as Escherichia coli and Bacillus subtilis have been published, making it possible to study the spatial organization of bacterial transcriptional regulatory networks. By combining TRNs and chromatin interaction data of E. coli and B. subtilis, we explored the spatial organization characteristics of bacterial TRNs in many aspects such as regulation directions (positive and negative), central nodes (hubs, bottlenecks), hierarchical levels (top, middle, bottom) and network motifs (feed-forward loops and single input modules) of the TRNs and found that the bacterial TRNs have a variety of stable spatial organization features under different physiological conditions that may be closely related with biological functions. Our findings provided new insights into the connection between transcriptional regulation and the spatial organization of chromosome in bacteria and might serve as a factual foundation for trying spatial-distance-based gene circuit design in synthetic biology.
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7
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Lensch S, Herschl MH, Ludwig CH, Sinha J, Hinks MM, Mukund A, Fujimori T, Bintu L. Dynamic spreading of chromatin-mediated gene silencing and reactivation between neighboring genes in single cells. eLife 2022; 11:e75115. [PMID: 35678392 PMCID: PMC9183234 DOI: 10.7554/elife.75115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/23/2022] [Indexed: 12/02/2022] Open
Abstract
In mammalian cells genes that are in close proximity can be transcriptionally coupled: silencing or activating one gene can affect its neighbors. Understanding these dynamics is important for natural processes, such as heterochromatin spreading during development and aging, and when designing synthetic gene regulation circuits. Here, we systematically dissect this process in single cells by recruiting and releasing repressive chromatin regulators at dual-gene synthetic reporters, and measuring how fast gene silencing and reactivation spread as a function of intergenic distance and configuration of insulator elements. We find that silencing by KRAB, associated with histone methylation, spreads between two genes within hours, with a time delay that increases with distance. This fast KRAB-mediated spreading is not blocked by the classical cHS4 insulators. Silencing by histone deacetylase HDAC4 of the upstream gene can also facilitate background silencing of the downstream gene by PRC2, but with a days-long delay that does not change with distance. This slower silencing can sometimes be stopped by insulators. Gene reactivation of neighboring genes is also coupled, with strong promoters and insulators determining the order of reactivation. Our data can be described by a model of multi-gene regulation that builds upon previous knowledge of heterochromatin spreading, where both gene silencing and gene reactivation can act at a distance, allowing for coordinated dynamics via chromatin regulator recruitment.
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Affiliation(s)
- Sarah Lensch
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | - Michael H Herschl
- University of California, Berkeley—University of California, San Francisco Graduate Program in BioengineeringBerkeleyUnited States
| | - Connor H Ludwig
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | - Joydeb Sinha
- Department of Chemical and Systems Biology, Stanford UniversityStanfordUnited States
| | - Michaela M Hinks
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | - Adi Mukund
- Biophysics Program, Stanford UniversityStanfordUnited States
| | - Taihei Fujimori
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | - Lacramioara Bintu
- Department of Bioengineering, Stanford UniversityStanfordUnited States
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8
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Exogenous artificial DNA forms chromatin structure with active transcription in yeast. SCIENCE CHINA. LIFE SCIENCES 2022; 65:851-860. [PMID: 34970711 DOI: 10.1007/s11427-021-2044-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 12/10/2021] [Indexed: 12/25/2022]
Abstract
Yeast artificial chromosomes (YACs) are important tools for sequencing, gene cloning, and transferring large quantities of genetic information. However, the structure and activity of YAC chromatin, as well as the unintended impacts of introducing foreign DNA sequences on DNA-associated biochemical events, have not been widely explored. Here, we showed that abundant genetic elements like TATA box and transcription factor-binding motifs occurred unintentionally in a previously reported data-carrying chromosome (dChr). In addition, we used state-of-the-art sequencing technologies to comprehensively profile the genetic, epigenetic, transcriptional, and proteomic characteristics of the exogenous dChr. We found that the data-carrying DNA formed active chromatin with high chromatin accessibility and H3K4 tri-methylation levels. The dChr also displayed highly pervasive transcriptional ability and transcribed hundreds of noncoding RNAs. The results demonstrated that exogenous artificial chromosomes formed chromatin structures and did not remain as naked or loose plasmids. A better understanding of the YAC chromatin nature will improve our ability to design better data-storage chromosomes.
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9
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Yao Y, Wen Q, Zhang T, Yu C, Chan KM, Gan H. Advances in Approaches to Study Chromatin-Mediated Epigenetic Memory. ACS Synth Biol 2022; 11:16-25. [PMID: 34965084 DOI: 10.1021/acssynbio.1c00394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chromatin structure contains critical epigenetic information in various forms, such as histone post-translational modifications (PTMs). The deposition of certain histone PTMs can remodel the chromatin structure, resulting in gene expression alteration. The epigenetic information carried by histone PTMs could be inherited by daughter cells to maintain the gene expression status. Recently, studies revealed that several conserved replisome proteins regulate the recycling of parental histones carrying epigenetic information in Saccharomyces cerevisiae. Hence, the proper recycling and deposition of parental histones onto newly synthesized DNA strands is presumed to be essential for epigenetic inheritance. Here, we first reviewed the fundamental mechanisms of epigenetic modification establishment and maintenance discovered within fungal models. Next, we discussed the functions of parental histone chaperones and the potential impacts of the parental histone recycling process on heterochromatin-mediated transcriptional silencing inheritance. Subsequently, we summarized novel synthetic biology approaches developed to analyze individual epigenetic components during epigenetic inheritance in fungal and mammalian systems. These newly emerged research paradigms enable us to dissect epigenetic systems in a bottom-up manner. Furthermore, we highlighted the approaches developed in this emerging field and discussed the potential applications of these engineered regulators to building synthetic epigenetic systems.
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Affiliation(s)
- Yuan Yao
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Qing Wen
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Tianjun Zhang
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Chuanhe Yu
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, United States
| | - Kui Ming Chan
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR 999077, China
- Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518172, China
| | - Haiyun Gan
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
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10
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Upstream Activation Sequence Can Function as an Insulator for Chromosomal Regulation of Heterologous Pathways Against Position Effects in Saccharomyces cerevisiae. Appl Biochem Biotechnol 2022; 194:1841-1849. [DOI: 10.1007/s12010-021-03654-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/03/2021] [Indexed: 11/25/2022]
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11
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The Therapeutic Potential of Epigenome-Modifying Drugs in Cardiometabolic Disease. CURRENT GENETIC MEDICINE REPORTS 2021. [DOI: 10.1007/s40142-021-00198-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Nakamura M, Gao Y, Dominguez AA, Qi LS. CRISPR technologies for precise epigenome editing. Nat Cell Biol 2021; 23:11-22. [PMID: 33420494 DOI: 10.1038/s41556-020-00620-7] [Citation(s) in RCA: 199] [Impact Index Per Article: 66.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 11/30/2020] [Indexed: 01/29/2023]
Abstract
The epigenome involves a complex set of cellular processes governing genomic activity. Dissecting this complexity necessitates the development of tools capable of specifically manipulating these processes. The repurposing of prokaryotic CRISPR systems has allowed for the development of diverse technologies for epigenome engineering. Here, we review the state of currently achievable epigenetic manipulations along with corresponding applications. With future optimization, CRISPR-based epigenomic editing stands as a set of powerful tools for understanding and controlling biological function.
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Affiliation(s)
- Muneaki Nakamura
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Yuchen Gao
- Department of Bioengineering, Stanford University, Stanford, CA, USA.,Cancer Biology Program, Stanford University, Stanford, CA, USA.,Mammoth Biosciences, South San Francisco, CA, USA
| | - Antonia A Dominguez
- Department of Bioengineering, Stanford University, Stanford, CA, USA.,Sana Biotechnology, South San Francisco, CA, USA
| | - Lei S Qi
- Department of Bioengineering, Stanford University, Stanford, CA, USA. .,Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA. .,Stanford ChEM-H Institute, Stanford University, Stanford, CA, USA.
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13
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Abstract
Determining whether and how a gene is transcribed are two of the central processes of life. The conceptual basis for understanding such gene regulation arose from pioneering biophysical studies in eubacteria. However, eukaryotic genomes exhibit vastly greater complexity, which raises questions not addressed by this bacterial paradigm. First, how is information integrated from many widely separated binding sites to determine how a gene is transcribed? Second, does the presence of multiple energy-expending mechanisms, which are absent from eubacterial genomes, indicate that eukaryotes are capable of improved forms of genetic information processing? An updated biophysical foundation is needed to answer such questions. We describe the linear framework, a graph-based approach to Markov processes, and show that it can accommodate many previous studies in the field. Under the assumption of thermodynamic equilibrium, we introduce a language of higher-order cooperativities and show how it can rigorously quantify gene regulatory properties suggested by experiment. We point out that fundamental limits to information processing arise at thermodynamic equilibrium and can only be bypassed through energy expenditure. Finally, we outline some of the mathematical challenges that must be overcome to construct an improved biophysical understanding of gene regulation.
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Affiliation(s)
- Felix Wong
- Institute for Medical Engineering & Science, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.,Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Jeremy Gunawardena
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA;
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14
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Rehman S, Aatif M, Rafi Z, Khan MY, Shahab U, Ahmad S, Farhan M. Effect of non-enzymatic glycosylation in the epigenetics of cancer. Semin Cancer Biol 2020; 83:543-555. [DOI: 10.1016/j.semcancer.2020.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/24/2020] [Accepted: 11/25/2020] [Indexed: 02/09/2023]
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15
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Pérez-Agustín A, Pinsach-Abuin M, Pagans S. Role of Non-Coding Variants in Brugada Syndrome. Int J Mol Sci 2020; 21:E8556. [PMID: 33202810 PMCID: PMC7698069 DOI: 10.3390/ijms21228556] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 12/15/2022] Open
Abstract
Brugada syndrome (BrS) is an inherited electrical heart disease associated with a high risk of sudden cardiac death (SCD). The genetic characterization of BrS has always been challenging. Although several cardiac ion channel genes have been associated with BrS, SCN5A is the only gene that presents definitive evidence for causality to be used for clinical diagnosis of BrS. However, more than 65% of diagnosed cases cannot be explained by variants in SCN5A or other genes. Therefore, in an important number of BrS cases, the underlying mechanisms are still elusive. Common variants, mostly located in non-coding regions, have emerged as potential modulators of the disease by affecting different regulatory mechanisms, including transcription factors (TFs), three-dimensional organization of the genome, or non-coding RNAs (ncRNAs). These common variants have been hypothesized to modulate the interindividual susceptibility of the disease, which could explain incomplete penetrance of BrS observed within families. Altogether, the study of both common and rare variants in parallel is becoming increasingly important to better understand the genetic basis underlying BrS. In this review, we aim to describe the challenges of studying non-coding variants associated with disease, re-examine the studies that have linked non-coding variants with BrS, and provide further evidence for the relevance of regulatory elements in understanding this cardiac disorder.
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Affiliation(s)
- Adrian Pérez-Agustín
- Department of Medical Sciences, School of Medicine, University of Girona, 17003 Girona, Spain;
- Biomedical Research Institute of Girona, 17190 Salt, Spain;
| | | | - Sara Pagans
- Department of Medical Sciences, School of Medicine, University of Girona, 17003 Girona, Spain;
- Biomedical Research Institute of Girona, 17190 Salt, Spain;
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16
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Su B, Song D, Yang F, Zhu H. Engineering a growth-phase-dependent biosynthetic pathway for carotenoid production in Saccharomyces cerevisiae. J Ind Microbiol Biotechnol 2020; 47:383-393. [PMID: 32236768 DOI: 10.1007/s10295-020-02271-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 03/08/2020] [Indexed: 12/11/2022]
Abstract
Metabolic engineering is usually focused on static control of microbial cell factories to efficient production of interested chemicals, though heterologous pathways compete with endogenous metabolism. However, products like carotenoids may cause metabolic burden on engineering strains, thus limiting product yields and influencing strain growth. Herein, a growth-phase-dependent regulation was developed to settle this matter, and its efficiency was verified using the heterogenous biosynthesis of lycopene in Saccharomyces cerevisiae as an example. Through growth-phase-dependent control of the lycopene biosynthetic pathway, limited step in MVA pathway, and competitive squalene pathway, production yield was increased by approximately 973-fold (from 0.034- to 33.1-mg/g CDW) and 1.48 g/L of production was obtained by one-stage fermentation in a 5-L bioreactor. Our study not only introduces an economically approach to the production of carotenoids, but also provides an example of dynamic regulation of biosynthetic pathways for metabolic engineering.
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Affiliation(s)
- Buli Su
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, People's Republic of China
| | - Dandan Song
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, People's Republic of China
| | - Fan Yang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, People's Republic of China
| | - Honghui Zhu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, People's Republic of China.
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17
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Matjusaitis M, Wagstaff LJ, Martella A, Baranowski B, Blin C, Gogolok S, Williams A, Pollard SM. Reprogramming of Fibroblasts to Oligodendrocyte Progenitor-like Cells Using CRISPR/Cas9-Based Synthetic Transcription Factors. Stem Cell Reports 2019; 13:1053-1067. [PMID: 31708478 PMCID: PMC6915844 DOI: 10.1016/j.stemcr.2019.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 10/12/2019] [Accepted: 10/13/2019] [Indexed: 01/06/2023] Open
Abstract
Cell lineage reprogramming via transgene overexpression of key master regulatory transcription factors has been well documented. However, the poor efficiency and lack of fidelity of this approach is problematic. Synthetic transcription factors (sTFs)-built from the repurposed CRISPR/Cas9 system-can activate endogenous target genes to direct differentiation or trigger lineage reprogramming. Here we explored whether sTFs could be used to steer mouse neural stem cells and mouse embryonic fibroblasts toward the oligodendrocyte lineage. We developed a non-viral modular expression system to enable stable multiplex delivery of pools of sTFs capable of transcriptional activation of three key oligodendrocyte lineage master regulatory genes (Sox10, Olig2, and Nkx6-2). Delivery of these sTFs could enhance neural stem cell differentiation and initiated mouse embryonic fibroblast direct reprograming toward oligodendrocyte progenitor-like cells. Our findings demonstrate the value of sTFs as tools for activating endogenous genes and directing mammalian cell-type identity.
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Affiliation(s)
- Mantas Matjusaitis
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Laura J Wagstaff
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Andrea Martella
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Bart Baranowski
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Carla Blin
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Sabine Gogolok
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Anna Williams
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Steven M Pollard
- MRC Centre for Regenerative Medicine and Edinburgh Cancer Research UK Centre, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK.
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18
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Fallet M, Luquet E, David P, Cosseau C. Epigenetic inheritance and intergenerational effects in mollusks. Gene 2019; 729:144166. [PMID: 31678264 DOI: 10.1016/j.gene.2019.144166] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 10/08/2019] [Accepted: 10/09/2019] [Indexed: 01/01/2023]
Abstract
Recent insights in evolutionary biology have shed light on epigenetic variation that interacts with genetic variation to convey heritable information. An important characteristic of epigenetic changes is that they can be produced in response to environmental cues and passed on to later generations, potentially facilitating later genetic adaptation. While our understanding of epigenetic mechanisms in vertebrates is rapidly growing, our knowledge about invertebrates remains lower, or is restricted to model organisms. Mollusks in particular, are a large group of invertebrates, with several species important for ecosystem function, human economy and health. In this review, we attempt to summarize the literature on epigenetic and intergenerational studies in mollusk species, with potential importance for adaptive evolution. Our review highlights that two molecular bearers of epigenetic information, DNA methylation and histone modifications, are key features for development in mollusk species, and both are sensitive to environmental conditions to which developing individuals are exposed. Further, although studies are still scarce, various environmental factors (e.g. predator cues, chemicals, parasites) can induce intergenerational effects on the phenotype (life-history traits, morphology, behaviour) of several mollusk taxa. More work is needed to better understand whether environmentally-induced changes in DNA methylation and histone modifications have phenotypic impacts, whether they can be inherited through generations and their role in intergenerational effects on phenotype. Such work may bring insights into the potential role of epigenetic in adaptation and evolution in mollusks.
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Affiliation(s)
- Manon Fallet
- IHPE, Univ. Montpellier, CNRS, Ifremer, Univ. Perpignan Via Domitia, Perpignan, France
| | - Emilien Luquet
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR5023 LEHNA, F-69622 Villeurbanne, France
| | - Patrice David
- CEFE, UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, IRD, EPHE, Montpellier, France
| | - Céline Cosseau
- IHPE, Univ. Montpellier, CNRS, Ifremer, Univ. Perpignan Via Domitia, Perpignan, France.
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19
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Giuliani C, Garagnani P, Franceschi C. Genetics of Human Longevity Within an Eco-Evolutionary Nature-Nurture Framework. Circ Res 2019; 123:745-772. [PMID: 30355083 DOI: 10.1161/circresaha.118.312562] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Human longevity is a complex trait, and to disentangle its basis has a great theoretical and practical consequences for biomedicine. The genetics of human longevity is still poorly understood despite several investigations that used different strategies and protocols. Here, we argue that such rather disappointing harvest is largely because of the extraordinary complexity of the longevity phenotype in humans. The capability to reach the extreme decades of human lifespan seems to be the result of an intriguing mixture of gene-environment interactions. Accordingly, the genetics of human longevity is here described as a highly context-dependent phenomenon, within a new integrated, ecological, and evolutionary perspective, and is presented as a dynamic process, both historically and individually. The available literature has been scrutinized within this perspective, paying particular attention to factors (sex, individual biography, family, population ancestry, social structure, economic status, and education, among others) that have been relatively neglected. The strength and limitations of the most powerful and used tools, such as genome-wide association study and whole-genome sequencing, have been discussed, focusing on prominently emerged genes and regions, such as apolipoprotein E, Forkhead box O3, interleukin 6, insulin-like growth factor-1, chromosome 9p21, 5q33.3, and somatic mutations among others. The major results of this approach suggest that (1) the genetics of longevity is highly population specific; (2) small-effect alleles, pleiotropy, and the complex allele timing likely play a major role; (3) genetic risk factors are age specific and need to be integrated in the light of the geroscience perspective; (4) a close relationship between genetics of longevity and genetics of age-related diseases (especially cardiovascular diseases) do exist. Finally, the urgent need of a global approach to the largely unexplored interactions between the 3 genetics of human body, that is, nuclear, mitochondrial, and microbiomes, is stressed. We surmise that the comprehensive approach here presented will help in increasing the above-mentioned harvest.
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Affiliation(s)
- Cristina Giuliani
- From the Department of Biological, Geological, and Environmental Sciences (BiGeA), Laboratory of Molecular Anthropology and Centre for Genome Biology (C.G.), University of Bologna, Italy.,School of Anthropology and Museum Ethnography, University of Oxford, United Kingdom (C.G.).,Interdepartmental Centre 'L. Galvani' (CIG), University of Bologna, Italy (C.G.)
| | - Paolo Garagnani
- Department of Experimental, Diagnostic, and Specialty Medicine (DIMES) (P.G.), University of Bologna, Italy.,Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet at Huddinge University Hospital, Stockholm, Sweden (P.G.)
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20
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Gebala M, Johnson SL, Narlikar GJ, Herschlag D. Ion counting demonstrates a high electrostatic field generated by the nucleosome. eLife 2019; 8:e44993. [PMID: 31184587 PMCID: PMC6584128 DOI: 10.7554/elife.44993] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 06/08/2019] [Indexed: 01/04/2023] Open
Abstract
In eukaryotes, a first step towards the nuclear DNA compaction process is the formation of a nucleosome, which is comprised of negatively charged DNA wrapped around a positively charged histone protein octamer. Often, it is assumed that the complexation of the DNA into the nucleosome completely attenuates the DNA charge and hence the electrostatic field generated by the molecule. In contrast, theoretical and computational studies suggest that the nucleosome retains a strong, negative electrostatic field. Despite their fundamental implications for chromatin organization and function, these opposing views of nucleosome electrostatics have not been experimentally tested. Herein, we directly measure nucleosome electrostatics and find that while nucleosome formation reduces the complex charge by half, the nucleosome nevertheless maintains a strong negative electrostatic field. Our studies highlight the importance of considering the polyelectrolyte nature of the nucleosome and its impact on processes ranging from factor binding to DNA compaction.
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Affiliation(s)
- Magdalena Gebala
- Department of BiochemistryStanford UniversityStanfordUnited States
| | - Stephanie L Johnson
- Department of Biochemistry and BiophysicsUniversity of California, San FranciscoSan FranciscoUnited States
| | - Geeta J Narlikar
- Department of Biochemistry and BiophysicsUniversity of California, San FranciscoSan FranciscoUnited States
| | - Dan Herschlag
- Department of BiochemistryStanford UniversityStanfordUnited States
- Department of ChemistryStanford UniversityStanfordUnited States
- ChEM-H InstituteStanford UniversityStanfordUnited States
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21
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Yang Y, Huang Y. The CRIPSR/Cas gene-editing system-an immature but useful toolkit for experimental and clinical medicine. Animal Model Exp Med 2019; 2:5-8. [PMID: 31016281 PMCID: PMC6431121 DOI: 10.1002/ame2.12061] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A Chinese scientist, Jiankui He, and his creation of the world's first genetically altered baby made headlines recently. As a newly developed gene-editing technique, the CRISPR/Cas system should not be applied to human beings for reproductive purposes until it has been extensively tested. However, numerous experimental research studies in human somatic, germline cells, and even in embryos, have been conducted, which have shown CRISPR/Cas to be a useful tool for human genome editing and a potential therapeutic method for future clinical use.
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Affiliation(s)
- Yuyan Yang
- State Key Laboratory of Medical Molecular BiologyInstitute of Basic Medical SciencesChinese Academy of Medical Sciences & Peking Union Medical CollegeBeijingChina
- Department of Medical GeneticsInstitute of Basic Medical SciencesChinese Academy of Medical Sciences & Peking Union Medical CollegeBeijingChina
| | - Yue Huang
- State Key Laboratory of Medical Molecular BiologyInstitute of Basic Medical SciencesChinese Academy of Medical Sciences & Peking Union Medical CollegeBeijingChina
- Department of Medical GeneticsInstitute of Basic Medical SciencesChinese Academy of Medical Sciences & Peking Union Medical CollegeBeijingChina
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22
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Lin JL, Ekas H, Deaner M, Alper HS. CRISPR-PIN: Modifying gene position in the nucleus via dCas9-mediated tethering. Synth Syst Biotechnol 2019; 4:73-78. [PMID: 30820479 PMCID: PMC6378893 DOI: 10.1016/j.synbio.2019.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/18/2019] [Accepted: 02/11/2019] [Indexed: 01/24/2023] Open
Abstract
Spatial organization of DNA within the nucleus is important for controlling DNA replication and repair, genetic recombination, and gene expression. Here, we present CRISPR-PIN, a CRISPR/dCas9-based tool that allows control of gene Position in the Nucleus for the yeast Saccharomyces cerevisiae. This approach utilizes a cohesin-dockerin interaction between dCas9 and a perinuclear protein. In doing so, we demonstrate that a single gRNA can enable programmable interaction of nuclear DNA with the nuclear periphery. We demonstrate the utility of this approach for two applications: the controlled segregation of an acentric plasmid and the re-localization of five endogenous loci. In both cases, we obtain results on par with prior reports using traditional, more cumbersome genetic systems. Thus, CRISPR-PIN offers the opportunity for future studies of chromosome biology and gene localization. dCas9 artificially localized to nuclear periphery using cohesin-dockerin tether to ESC1. Targeting dCas9 to acentric plasmid allows rescue of plasmid segregation phenotype. 5 unique chromosomal loci re-localized to nuclear periphery. dCas9 tethering allows control over target gene Position In the Nucleus (CRISPR-PIN).
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Affiliation(s)
- Jyun-Liang Lin
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton St. Stop C0400, Austin, TX 78712, USA
| | - Holly Ekas
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton St. Stop C0400, Austin, TX 78712, USA
| | - Matthew Deaner
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton St. Stop C0400, Austin, TX 78712, USA
| | - Hal S Alper
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton St. Stop C0400, Austin, TX 78712, USA.,Institute for Cellular and Molecular Biology, The University of Texas at Austin, 2500 Speedway Avenue, Austin, TX 78712, USA
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23
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Abstract
The advent of locus-specific protein recruitment technologies has enabled a new class of studies in chromatin biology. Epigenome editors enable biochemical modifications of chromatin at almost any specific endogenous locus. Their locus specificity unlocks unique information including the functional roles of distinct modifications at specific genomic loci. Given the growing interest in using these tools for biological and translational studies, there are many specific design considerations depending on the scientific question or clinical need. Here we present and discuss important design considerations and challenges regarding the biochemical and locus specificities of epigenome editors. These include how to account for the complex biochemical diversity of chromatin; control for potential interdependency of epigenome editors and their resultant modifications; avoid sequestration effects; quantify the locus specificity of epigenome editors; and improve locus specificity by considering concentration, affinity, avidity, and sequestration effects.
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24
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Singh K, Jha NK, Thakur A. Spatiotemporal chromatin dynamics - A telltale of circadian epigenetic gene regulation. Life Sci 2019; 221:377-391. [PMID: 30721705 DOI: 10.1016/j.lfs.2019.02.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 01/27/2019] [Accepted: 02/01/2019] [Indexed: 01/08/2023]
Abstract
Over the course of evolution, nature has forced organisms under selection pressure to hardwire an internal time keeping device that defines 24 h of a daily cycle of physiological and behavioral rhythms, known as circadian rhythms. At the cellular level, the cycle is governed by significant fractions of transcriptomes, which are under the control of transcriptional and translational feedback loop of clock genes. Intriguingly, this feedback loop is regulated at multiple stratums such as at the transcriptional and translational levels, which direct a cell towards producing a robust rhythm by sustaining the repeated stoichiometry of protein products. Moreover, with the advent of state of the art paradigms, epigenetic regulation of circadian rhythms has been becoming more evident at present time. Light-induced recurring fluctuations in chromatin acetylation concurrent with the binding of RNA Pol II and integration of miRNAs monitor the chromatin modifiers or clock genes expression to drive temporal rhythmicity. Furthermore, CLOCK protein intrinsic histone acetyl transferase activity, the interaction of CLOCK-BMAL-1 with HAT enzymes, and the involvement of many histone deacetylases also maintain the rhythmic protein profile. Additionally, the critical role of the rhythmic methylation pattern of clock genes in battery of cancer and metabolic disorders also defines its importance. Therefore, in this review, we focused on accumulating all the present data available on epigenetics and circadian rhythms. Interestingly, we also gathered evidence from the available literature pinpointing towards the dynamic nature of chromatin architecture governed by long and short-range regulatory elements DNA contacts arising daily, that was thought to be steady otherwise.
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Affiliation(s)
- Kunal Singh
- Department of Biotechnology, Noida Institute of Engineering & Technology (NIET), Greater Noida, India.
| | - Niraj Kumar Jha
- Department of Biotechnology, Noida Institute of Engineering & Technology (NIET), Greater Noida, India
| | - Abhimanyu Thakur
- Department of Pharmaceutical Sciences and Technology, Birla Institute of Technology, Mesra, Ranchi, India
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25
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Abstract
Measuring biological data across time and space is critical for understanding complex biological processes and for various biosurveillance applications. However, such data are often inaccessible or difficult to directly obtain. Less invasive, more robust and higher-throughput biological recording tools are needed to profile cells and their environments. DNA-based cellular recording is an emerging and powerful framework for tracking intracellular and extracellular biological events over time across living cells and populations. Here, we review and assess DNA recorders that utilize CRISPR nucleases, integrases and base-editing strategies, as well as recombinase and polymerase-based methods. Quantitative characterization, modelling and evaluation of these DNA-recording modalities can guide their design and implementation for specific application areas.
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Affiliation(s)
- Ravi U Sheth
- Department of Systems Biology, Columbia University Medical Center, New York, NY, USA
- Integrated Program in Cellular, Molecular and Biomedical Studies, Columbia University, New York, NY, USA
| | - Harris H Wang
- Department of Systems Biology, Columbia University Medical Center, New York, NY, USA.
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA.
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26
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Su-Keene EJ, Bonilla MM, Padua MV, Zeh DW, Zeh JA. Simulated climate warming and mitochondrial haplogroup modulate testicular small non-coding RNA expression in the neotropical pseudoscorpion, Cordylochernes scorpioides. ENVIRONMENTAL EPIGENETICS 2018; 4:dvy027. [PMID: 30595847 PMCID: PMC6305488 DOI: 10.1093/eep/dvy027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Revised: 11/22/2018] [Accepted: 10/21/2018] [Indexed: 06/01/2023]
Abstract
Recent theory suggests that tropical terrestrial arthropods are at significant risk from climate warming. Metabolic rate in such ectothermic species increases exponentially with environmental temperature, and a small temperature increase in a hot environment can therefore have a greater physiological impact than a large temperature increase in a cool environment. In two recent studies of the neotropical pseudoscorpion, Cordylochernes scorpioides, simulated climate warming significantly decreased survival, body size and level of sexual dimorphism. However, these effects were minor compared with catastrophic consequences for male fertility and female fecundity, identifying reproduction as the life stage most vulnerable to climate warming. Here, we examine the effects of chronic high-temperature exposure on epigenetic regulation in C. scorpioides in the context of naturally occurring variation in mitochondrial DNA. Epigenetic mechanisms, including DNA methylation, histone modifications and small non-coding RNA (sncRNA) expression, are particularly sensitive to environmental factors such as temperature, which can induce changes in epigenetic states and phenotypes that may be heritable across generations. Our results indicate that exposure of male pseudoscorpions to elevated temperature significantly altered the expression of >60 sncRNAs in testicular tissue, specifically microRNAs and piwi-interacting RNAs. Mitochondrial haplogroup was also a significant factor influencing both sncRNAs and mitochondrial gene expression. These findings demonstrate that chronic heat stress causes changes in epigenetic profiles that may account for reproductive dysfunction in C. scorpioides males. Moreover, through its effects on epigenetic regulation, mitochondrial DNA polymorphism may provide the potential for an adaptive evolutionary response to climate warming.
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Affiliation(s)
- Eleanor J Su-Keene
- Department of Biology, University of Nevada, Reno, Reno, NV, USA
- Department of Educational Leadership and Research Methodology, Florida Atlantic University, Boca Raton, FL, USA
| | - Melvin M Bonilla
- Graduate Program in Ecology, Evolution and Conservation Biology, University of Nevada, Reno, Reno, NV, USA
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL, USA
| | - Michael V Padua
- Department of Biology, University of Nevada, Reno, Reno, NV, USA
- University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - David W Zeh
- Department of Biology, University of Nevada, Reno, Reno, NV, USA
- Graduate Program in Ecology, Evolution and Conservation Biology, University of Nevada, Reno, Reno, NV, USA
| | - Jeanne A Zeh
- Department of Biology, University of Nevada, Reno, Reno, NV, USA
- Graduate Program in Ecology, Evolution and Conservation Biology, University of Nevada, Reno, Reno, NV, USA
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27
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Burt A, Deredec A. Self-limiting population genetic control with sex-linked genome editors. Proc Biol Sci 2018; 285:rspb.2018.0776. [PMID: 30051868 PMCID: PMC6083257 DOI: 10.1098/rspb.2018.0776] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 06/28/2018] [Indexed: 12/30/2022] Open
Abstract
In male heterogametic species the Y chromosome is transmitted solely from fathers to sons, and is selected for based only on its impacts on male fitness. This fact can be exploited to develop efficient pest control strategies that use Y-linked editors to disrupt the fitness of female descendants. With simple population genetic and dynamic models we show that Y-linked editors can be substantially more efficient than other self-limiting strategies and, while not as efficient as gene drive approaches, are expected to have less impact on non-target populations with which there is some gene flow. Efficiency can be further augmented by simultaneously releasing an autosomal X-shredder construct, in either the same or different males. Y-linked editors may be an attractive option to consider when efficient control of a species is desired in some locales but not others.
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Affiliation(s)
- Austin Burt
- Life Sciences, Imperial College, Silwood Park, Ascot SL5 7PY, UK
| | - Anne Deredec
- UMR BIOGER, INRA AgroParisTech, Université Paris-Saclay, Avenue Lucien Bretignières, 78850 Thiverval-Grignon, France
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28
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Pulecio J, Verma N, Mejía-Ramírez E, Huangfu D, Raya A. CRISPR/Cas9-Based Engineering of the Epigenome. Cell Stem Cell 2018; 21:431-447. [PMID: 28985525 DOI: 10.1016/j.stem.2017.09.006] [Citation(s) in RCA: 189] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Determining causal relationships between distinct chromatin features and gene expression, and ultimately cell behavior, remains a major challenge. Recent developments in targetable epigenome-editing tools enable us to assign direct transcriptional and functional consequences to locus-specific chromatin modifications. This Protocol Review discusses the unprecedented opportunity that CRISPR/Cas9 technology offers for investigating and manipulating the epigenome to facilitate further understanding of stem cell biology and engineering of stem cells for therapeutic applications. We also provide technical considerations for standardization and further improvement of the CRISPR/Cas9-based tools to engineer the epigenome.
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Affiliation(s)
- Julian Pulecio
- Center of Regenerative Medicine in Barcelona (CMRB), Hospital Duran i Reynals, 3rd floor, Avenue Gran Via 199-203, Hospitalet de Llobregat, 08908 Barcelona, Spain; Center for Networked Biomedical Research on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28029 Madrid, Spain; Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, New York, NY 10065, USA
| | - Nipun Verma
- Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, New York, NY 10065, USA; Weill Graduate School of Medical Sciences at Cornell University/The Rockefeller University/Sloan Kettering Institute Tri-Institutional M.D.-Ph.D. Program, 1300 York Avenue, New York, NY 10065, USA
| | - Eva Mejía-Ramírez
- Center of Regenerative Medicine in Barcelona (CMRB), Hospital Duran i Reynals, 3rd floor, Avenue Gran Via 199-203, Hospitalet de Llobregat, 08908 Barcelona, Spain
| | - Danwei Huangfu
- Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, New York, NY 10065, USA.
| | - Angel Raya
- Center of Regenerative Medicine in Barcelona (CMRB), Hospital Duran i Reynals, 3rd floor, Avenue Gran Via 199-203, Hospitalet de Llobregat, 08908 Barcelona, Spain; Center for Networked Biomedical Research on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28029 Madrid, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain.
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29
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Anton T, Karg E, Bultmann S. Applications of the CRISPR/Cas system beyond gene editing. Biol Methods Protoc 2018; 3:bpy002. [PMID: 32161796 PMCID: PMC6994046 DOI: 10.1093/biomethods/bpy002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 02/28/2018] [Accepted: 04/03/2018] [Indexed: 12/26/2022] Open
Abstract
Since the discovery of the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system (Cas) as a tool for gene editing a plethora of locus-specific as well as genome-wide approaches have been developed that allow efficient and reproducible manipulation of genomic sequences. However, the seemingly unbound potential of CRISPR/Cas does not stop with its utilization as a site-directed nuclease. Mutations in its catalytic centers render Cas9 (dCas9) a universal recruitment platform that can be utilized to control transcription, visualize DNA sequences, investigate in situ proteome compositions and manipulate epigenetic modifications at user-defined genomic loci. In this review, we give a comprehensive introduction and overview of the development, improvement and application of recent dCas9-based approaches.
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Affiliation(s)
- Tobias Anton
- Department of Biology II and Center for Integrated Protein Science Munich (CIPSM), LMU Munich, 82152 Martinsried, Germany
| | - Elisabeth Karg
- Department of Biology II and Center for Integrated Protein Science Munich (CIPSM), LMU Munich, 82152 Martinsried, Germany
| | - Sebastian Bultmann
- Department of Biology II and Center for Integrated Protein Science Munich (CIPSM), LMU Munich, 82152 Martinsried, Germany
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30
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In situ biomolecule production by bacteria; a synthetic biology approach to medicine. J Control Release 2018; 275:217-228. [DOI: 10.1016/j.jconrel.2018.02.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 02/14/2018] [Accepted: 02/15/2018] [Indexed: 02/06/2023]
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Bittihn P, Din MO, Tsimring LS, Hasty J. Rational engineering of synthetic microbial systems: from single cells to consortia. Curr Opin Microbiol 2018; 45:92-99. [PMID: 29574330 DOI: 10.1016/j.mib.2018.02.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 02/06/2018] [Accepted: 02/19/2018] [Indexed: 12/11/2022]
Abstract
One promise of synthetic biology is to provide solutions for biomedical and industrial problems by rational design of added functionality in living systems. Microbes are at the forefront of this biological engineering endeavor due to their general ease of handling and their relevance in many potential applications from fermentation to therapeutics. In recent years, the field has witnessed an explosion of novel regulatory tools, from synthetic orthogonal transcription factors to posttranslational mechanisms for increased control over the behavior of synthetic circuits. Tool development has been paralleled by the discovery of principles that enable increased modularity and the management of host-circuit interactions. Engineered cell-to-cell communication bridges the scales from intracellular to population-level coordination. These developments facilitate the translation of more than a decade of circuit design into applications.
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Affiliation(s)
- Philip Bittihn
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - M Omar Din
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lev S Tsimring
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jeff Hasty
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA; Molecular Biology Section, Division of Biological Science, University of California, San Diego, La Jolla, CA 92093, USA.
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32
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Computational methods for analyzing genome-wide chromosome conformation capture data. Curr Opin Biotechnol 2018; 54:98-105. [PMID: 29550705 DOI: 10.1016/j.copbio.2018.01.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 12/31/2017] [Accepted: 01/22/2018] [Indexed: 11/23/2022]
Abstract
In all organisms, chromatin is packed to fulfil structural constraints and functional requirements. The hierarchical model of chromatin organization in the 3D nuclear space encompasses different topologies at diverse scale lengths, with chromosomes occupying distinct volumes, further organized in compartments, inside which the chromatin fibers fold into large domains and short-range loops. In the recent years, the combination of chromosome conformation capture (3C) techniques and high-throughput sequencing allowed probing chromatin spatial organization at the whole genome-scale. 3C-based methods produce enormous amounts of genomic data that are analyzed using ad-hoc computational procedures. Here, we review the common pipelines and methods for the analysis of genome-wide chromosome conformation capture data, highlighting recent developments in key steps for the identification of chromatin structures.
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Abstract
The programming of new functions into mammalian cells has tremendous application in research and medicine. Continued improvements in the capacity to sequence and synthesize DNA have rapidly increased our understanding of mechanisms of gene function and regulation on a genome-wide scale and have expanded the set of genetic components available for programming cell biology. The invention of new research tools, including targetable DNA-binding systems such as CRISPR/Cas9 and sensor-actuator devices that can recognize and respond to diverse chemical, mechanical, and optical inputs, has enabled precise control of complex cellular behaviors at unprecedented spatial and temporal resolution. These tools have been critical for the expansion of synthetic biology techniques from prokaryotic and lower eukaryotic hosts to mammalian systems. Recent progress in the development of genome and epigenome editing tools and in the engineering of designer cells with programmable genetic circuits is expanding approaches to prevent, diagnose, and treat disease and to establish personalized theranostic strategies for next-generation medicines. This review summarizes the development of these enabling technologies and their application to transforming mammalian synthetic biology into a distinct field in research and medicine.
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Affiliation(s)
- Joshua B Black
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708; , .,Center for Genomic and Computational Biology, Duke University, Durham, North Carolina 27708
| | - Pablo Perez-Pinera
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801; .,Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Charles A Gersbach
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708; , .,Center for Genomic and Computational Biology, Duke University, Durham, North Carolina 27708.,Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina 27710
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Abstract
Manipulation of gene expression can be facilitated by editing the genome or the epigenome. Precise genome editing is traditionally achieved by using designer nucleases which are generally exploited to eliminate a specific gene product. Upon the introduction of a site-specific DNA double-strand break (DSB) by the nuclease, endogenous DSB repair mechanisms are in turn harnessed to induce DNA sequence changes that can result in target gene inactivation. Minimal off-target effects can be obtained by endowing designer nucleases with the highly specific DNA-binding domain (DBD) derived from transcription activator-like effectors (TALEs). In contrast, epigenome editing allows gene expression control without inducing changes in the DNA sequence by specifically altering epigenetic marks, as histone tails modifications or DNA methylation patterns within promoter or enhancer regions. Importantly, this approach allows both up- and downregulation of the target gene expression, and the effect is generally reversible. TALE-based designer epigenome modifiers combine the high specificity of TALE-derived DBDs with the power of epigenetic modifier domains to induce fast and long-lasting changes in the epigenetic landscape of a target gene and control its expression. Here we provide a detailed description for the generation of TALE-based designer epigenome modifiers and of a suitable reporter cell line to easily monitor their activity.
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Affiliation(s)
- Sandra Nitsch
- Institute for Cell and Gene Therapy & Center for Chronic Immunodeficiency, Medical Center-University of Freiburg, Freiburg, Germany
| | - Claudio Mussolino
- Institute for Cell and Gene Therapy & Center for Chronic Immunodeficiency, Medical Center-University of Freiburg, Freiburg, Germany.
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Stepper P, Kungulovski G, Jurkowska RZ, Chandra T, Krueger F, Reinhardt R, Reik W, Jeltsch A, Jurkowski TP. Efficient targeted DNA methylation with chimeric dCas9-Dnmt3a-Dnmt3L methyltransferase. Nucleic Acids Res 2017; 45:1703-1713. [PMID: 27899645 PMCID: PMC5389507 DOI: 10.1093/nar/gkw1112] [Citation(s) in RCA: 192] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 10/28/2016] [Indexed: 12/19/2022] Open
Abstract
DNA methylation plays a critical role in the regulation and maintenance of cell-type specific transcriptional programs. Targeted epigenome editing is an emerging technology to specifically regulate cellular gene expression in order to modulate cell phenotypes or dissect the epigenetic mechanisms involved in their control. In this work, we employed a DNA methyltransferase Dnmt3a–Dnmt3L construct fused to the nuclease-inactivated dCas9 programmable targeting domain to introduce DNA methylation into the human genome specifically at the EpCAM, CXCR4 and TFRC gene promoters. We show that targeting of these loci with single gRNAs leads to efficient and widespread methylation of the promoters. Multiplexing of several guide RNAs does not increase the efficiency of methylation. Peaks of targeted methylation were observed around 25 bp upstream and 40 bp downstream of the PAM site, while 20–30 bp of the binding site itself are protected against methylation. Potent methylation is dependent on the multimerization of Dnmt3a/Dnmt3L complexes on the DNA. Furthermore, the introduced methylation causes transcriptional repression of the targeted genes. These new programmable epigenetic editors allow unprecedented control of the DNA methylation status in cells and will lead to further advances in the understanding of epigenetic signaling.
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Affiliation(s)
- Peter Stepper
- Institute of Biochemistry, Pfaffenwaldring 55, Faculty of Chemistry, University of Stuttgart, D-70569 Stuttgart, Germany
| | - Goran Kungulovski
- Institute of Biochemistry, Pfaffenwaldring 55, Faculty of Chemistry, University of Stuttgart, D-70569 Stuttgart, Germany
| | - Renata Z Jurkowska
- Institute of Biochemistry, Pfaffenwaldring 55, Faculty of Chemistry, University of Stuttgart, D-70569 Stuttgart, Germany
| | - Tamir Chandra
- Epigenetics Programme, The Babraham Institute, Cambridge CB22 3AT, UK; The Welcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | | | - Richard Reinhardt
- Max Planck Genome-Centre Cologne, Carl-von-Linné-Weg 10, D-50829 Cologne, Germany
| | - Wolf Reik
- Epigenetics Programme, The Babraham Institute, Cambridge CB22 3AT, UK; The Welcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | - Albert Jeltsch
- Institute of Biochemistry, Pfaffenwaldring 55, Faculty of Chemistry, University of Stuttgart, D-70569 Stuttgart, Germany
| | - Tomasz P Jurkowski
- Institute of Biochemistry, Pfaffenwaldring 55, Faculty of Chemistry, University of Stuttgart, D-70569 Stuttgart, Germany
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Portet A, Pinaud S, Tetreau G, Galinier R, Cosseau C, Duval D, Grunau C, Mitta G, Gourbal B. Integrated multi-omic analyses in Biomphalaria-Schistosoma dialogue reveal the immunobiological significance of FREP-SmPoMuc interaction. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 75:16-27. [PMID: 28257854 DOI: 10.1016/j.dci.2017.02.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 02/23/2017] [Accepted: 02/26/2017] [Indexed: 05/16/2023]
Abstract
The fresh water snail Biomphalaria glabrata is one of the vectors of the trematode pathogen Schistosoma mansoni, which is one of the agents responsible of human schistosomiasis. In this host-parasite interaction, co-evolutionary dynamic results into an infectivity mosaic known as compatibility polymorphism. Integrative approaches including large scale molecular approaches have been conducted in recent years to improve our understanding of the mechanisms underlying compatibility. This review presents the combination of integrated Multi-Omic approaches leading to the discovery of two repertoires of polymorphic and/or diversified interacting molecules: the parasite antigens S. mansoni polymorphic mucins (SmPoMucs) and the B. glabrata immune receptors fibrinogen-related proteins (FREPs). We argue that their interactions may be major components for defining the compatible/incompatible status of a specific snail/schistosome combination.
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Affiliation(s)
- Anaïs Portet
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Silvain Pinaud
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Guillaume Tetreau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Richard Galinier
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Céline Cosseau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - David Duval
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Christoph Grunau
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Guillaume Mitta
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France
| | - Benjamin Gourbal
- Univ. Perpignan Via Domitia, IHPE UMR 5244, IFREMER, Univ. Montpellier, F-66860 Perpignan, France.
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37
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CRISPR editing in biological and biomedical investigation. J Cell Physiol 2017; 233:3875-3891. [DOI: 10.1002/jcp.26141] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 08/07/2017] [Indexed: 12/23/2022]
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38
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Brown AJ, Kalsi D, Fernandez-Martell A, Cartwright J, Barber NOW, Patel YD, Turner R, Bryant CL, Johari YB, James DC. Expression Systems for Recombinant Biopharmaceutical Production by Mammalian Cells in Culture. METHODS AND PRINCIPLES IN MEDICINAL CHEMISTRY 2017. [DOI: 10.1002/9783527699124.ch13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Adam J. Brown
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Devika Kalsi
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | | | - Joe Cartwright
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Nicholas O. W. Barber
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Yash D. Patel
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | | | - Claire L. Bryant
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Yusuf B. Johari
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - David C. James
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
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39
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Gander MW, Vrana JD, Voje WE, Carothers JM, Klavins E. Digital logic circuits in yeast with CRISPR-dCas9 NOR gates. Nat Commun 2017; 8:15459. [PMID: 28541304 PMCID: PMC5458518 DOI: 10.1038/ncomms15459] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 03/31/2017] [Indexed: 12/17/2022] Open
Abstract
Natural genetic circuits enable cells to make sophisticated digital decisions. Building equally complex synthetic circuits in eukaryotes remains difficult, however, because commonly used components leak transcriptionally, do not arbitrarily interconnect or do not have digital responses. Here, we designed dCas9-Mxi1-based NOR gates in Saccharomyces cerevisiae that allow arbitrary connectivity and large genetic circuits. Because we used the chromatin remodeller Mxi1, our gates showed minimal leak and digital responses. We built a combinatorial library of NOR gates that directly convert guide RNA (gRNA) inputs into gRNA outputs, enabling the gates to be 'wired' together. We constructed logic circuits with up to seven gRNAs, including repression cascades with up to seven layers. Modelling predicted the NOR gates have effectively zero transcriptional leak explaining the limited signal degradation in the circuits. Our approach enabled the largest, eukaryotic gene circuits to date and will form the basis for large, synthetic, cellular decision-making systems.
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Affiliation(s)
- Miles W. Gander
- Department of Electrical Engineering, University of Washington, Seattle, Washington 98195, USA
| | - Justin D. Vrana
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA
| | - William E. Voje
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, USA
| | - James M. Carothers
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, USA
- Center for Synthetic Biology, University of Washington, Seattle, Washington 98195, USA
| | - Eric Klavins
- Department of Electrical Engineering, University of Washington, Seattle, Washington 98195, USA
- Center for Synthetic Biology, University of Washington, Seattle, Washington 98195, USA
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40
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Angiolilli C, Baeten DL, Radstake TR, Reedquist KA. The acetyl code in rheumatoid arthritis and other rheumatic diseases. Epigenomics 2017; 9:447-461. [DOI: 10.2217/epi-2016-0136] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Growing evidence supports the idea that aberrancies in epigenetic processes contribute to the onset and progression of human immune-mediated inflammatory diseases, such as rheumatoid arthritis (RA). Epigenetic regulators of histone tail modifications play a role in chromatin accessibility and transcriptional responses to inflammatory stimuli. Among these, histone deacetylases (HDACs) regulate the acetylation status of histones and nonhistone proteins, essential for immune responses. Broad-spectrum HDAC inhibitors are well-known anti-inflammatory agents and reduce disease severity in animal models of arthritis; however, selective HDAC inhibitors remain poorly studied. In this review, we describe emerging findings regarding the aberrant acetyl code in RA and other rheumatic disorders which may help identify not only novel diagnostic and prognostic clinical biomarkers for RA, but also new targets for epigenetic pharmacological applications.
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Affiliation(s)
- Chiara Angiolilli
- Laboratory of Translational Immunology & Department of Rheumatology & Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
- Amsterdam Rheumatology & Immunology Center, Department of Clinical Immunology & Rheumatology, Department of Experimental Immunology Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Dominique L Baeten
- Amsterdam Rheumatology & Immunology Center, Department of Clinical Immunology & Rheumatology, Department of Experimental Immunology Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Timothy R Radstake
- Laboratory of Translational Immunology & Department of Rheumatology & Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Kris A Reedquist
- Laboratory of Translational Immunology & Department of Rheumatology & Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
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41
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Komor AC, Badran AH, Liu DR. CRISPR-Based Technologies for the Manipulation of Eukaryotic Genomes. Cell 2017; 168:20-36. [PMID: 27866654 PMCID: PMC5235943 DOI: 10.1016/j.cell.2016.10.044] [Citation(s) in RCA: 607] [Impact Index Per Article: 86.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 10/20/2016] [Accepted: 10/22/2016] [Indexed: 12/18/2022]
Abstract
The CRISPR-Cas9 RNA-guided DNA endonuclease has contributed to an explosion of advances in the life sciences that have grown from the ability to edit genomes within living cells. In this Review, we summarize CRISPR-based technologies that enable mammalian genome editing and their various applications. We describe recent developments that extend the generality, DNA specificity, product selectivity, and fundamental capabilities of natural CRISPR systems, and we highlight some of the remarkable advancements in basic research, biotechnology, and therapeutics science that these developments have facilitated.
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Affiliation(s)
- Alexis C Komor
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA; Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | - Ahmed H Badran
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA; Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | - David R Liu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA; Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA.
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42
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Information Integration and Energy Expenditure in Gene Regulation. Cell 2017; 166:234-44. [PMID: 27368104 DOI: 10.1016/j.cell.2016.06.012] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 03/08/2016] [Accepted: 06/01/2016] [Indexed: 11/22/2022]
Abstract
The quantitative concepts used to reason about gene regulation largely derive from bacterial studies. We show that this bacterial paradigm cannot explain the sharp expression of a canonical developmental gene in response to a regulating transcription factor (TF). In the absence of energy expenditure, with regulatory DNA at thermodynamic equilibrium, information integration across multiple TF binding sites can generate the required sharpness, but with strong constraints on the resultant "higher-order cooperativities." Even with such integration, there is a "Hopfield barrier" to sharpness; for n TF binding sites, this barrier is represented by the Hill function with the Hill coefficient n. If, however, energy is expended to maintain regulatory DNA away from thermodynamic equilibrium, as in kinetic proofreading, this barrier can be breached and greater sharpness achieved. Our approach is grounded in fundamental physics, leads to testable experimental predictions, and suggests how a quantitative paradigm for eukaryotic gene regulation can be formulated.
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43
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Nyer DB, Daer RM, Vargas D, Hom C, Haynes KA. Regulation of cancer epigenomes with a histone-binding synthetic transcription factor. NPJ Genom Med 2017; 2. [PMID: 28919981 PMCID: PMC5600530 DOI: 10.1038/s41525-016-0002-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Chromatin proteins have expanded the mammalian synthetic biology toolbox by enabling control of active and silenced states at endogenous genes. Others have reported synthetic proteins that bind DNA and regulate genes by altering chromatin marks, such as histone modifications. Previously, we reported the first synthetic transcriptional activator, the "Polycomb-based transcription factor" (PcTF) that reads histone modifications through a protein-protein interaction between the polycomb chromodomain motif and trimethylated lysine 27 of histone H3 (H3K27me3). Here, we describe the genome-wide behavior of the polycomb-based transcription factor fusion protein. Transcriptome and chromatin profiling revealed several polycomb-based transcription factor-sensitive promoter regions marked by distal H3K27me3 and proximal fusion protein binding. These results illuminate a mechanism in which polycomb-based transcription factor interactions bridge epigenomic marks with the transcription initiation complex at target genes. In three cancer-derived human cell lines tested here, some target genes encode developmental regulators and tumor suppressors. Thus, the polycomb-based transcription factor represents a powerful new fusion protein-based method for cancer research and treatment where silencing marks are translated into direct gene activation.
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Affiliation(s)
- David B Nyer
- School of Biological and Health Systems Engineering, Arizona State University, 501 E Tyler Mall, Box 9709, Tempe, AZ 85287, USA
| | - Rene M Daer
- School of Biological and Health Systems Engineering, Arizona State University, 501 E Tyler Mall, Box 9709, Tempe, AZ 85287, USA
| | - Daniel Vargas
- School of Biological and Health Systems Engineering, Arizona State University, 501 E Tyler Mall, Box 9709, Tempe, AZ 85287, USA
| | - Caroline Hom
- School of Biological and Health Systems Engineering, Arizona State University, 501 E Tyler Mall, Box 9709, Tempe, AZ 85287, USA
| | - Karmella A Haynes
- School of Biological and Health Systems Engineering, Arizona State University, 501 E Tyler Mall, Box 9709, Tempe, AZ 85287, USA
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44
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Tokuda N, Sasai M. Heterogeneous Spatial Distribution of Transcriptional Activity in Budding Yeast Nuclei. Biophys J 2016; 112:491-504. [PMID: 28040197 PMCID: PMC5300786 DOI: 10.1016/j.bpj.2016.11.3201] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 11/23/2016] [Accepted: 11/29/2016] [Indexed: 01/22/2023] Open
Abstract
Recent microscopic and simulation studies have shown that the genome structure fluctuates dynamically in the nuclei of budding yeast Saccharomyces cerevisiae. This genome-wide movement should lead to the fluctuations of individual genes in their territorial regions. This raises an intriguing question of whether the resulting distribution of genes is correlated to their transcriptional activity. An effective method for examining this correlation is to analyze how the spatial distribution of genes and their transcriptional activity are modified by mutation. In this study, we analyzed the modification observed in a budding yeast mutant in which genes necessary for anchoring telomeres to the nuclear envelope, yku70 and esc1, are silenced. Taddei et al. reported that 60 genes are clearly misregulated by this mutation, with 28 and 32 genes downregulated and upregulated, respectively. We calculated the probability density maps of the misregulated genes using a model of dynamical movement of the yeast genome in both wild-type (WT) and yku70 esc1 mutant and showed that the density of downregulated genes is larger near the nucleolus, whereas the density of upregulated genes is larger at the opposite side of the nucleus. By comparing these genes with those highly (top 200 of transcriptome) and lowly (bottom 200) expressed, we showed that the simulated distribution of 28 downregulated (12 out of 32 upregulated) genes has a distinctly larger overlap with the distribution of lowly (highly) expressed genes in the mutant than in the WT. The remaining 20 upregulated genes are localized near the nuclear envelope both in the WT and in the mutant. These results showed that the transcriptional level of genes is affected by their spatial distribution, thus highlighting the importance of the structural regulation in the yeast genome.
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Affiliation(s)
- Naoko Tokuda
- Department of Computational Science and Engineering, Nagoya University, Nagoya, Japan
| | - Masaki Sasai
- Department of Computational Science and Engineering, Nagoya University, Nagoya, Japan; Department of Applied Physics, Nagoya University, Nagoya, Japan.
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45
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Inheritable Silencing of Endogenous Genes by Hit-and-Run Targeted Epigenetic Editing. Cell 2016; 167:219-232.e14. [PMID: 27662090 PMCID: PMC5039111 DOI: 10.1016/j.cell.2016.09.006] [Citation(s) in RCA: 319] [Impact Index Per Article: 39.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 06/18/2016] [Accepted: 09/02/2016] [Indexed: 12/29/2022]
Abstract
Gene silencing is instrumental to interrogate gene function and holds promise for therapeutic applications. Here, we repurpose the endogenous retroviruses’ silencing machinery of embryonic stem cells to stably silence three highly expressed genes in somatic cells by epigenetics. This was achieved by transiently expressing combinations of engineered transcriptional repressors that bind to and synergize at the target locus to instruct repressive histone marks and de novo DNA methylation, thus ensuring long-term memory of the repressive epigenetic state. Silencing was highly specific, as shown by genome-wide analyses, sharply confined to the targeted locus without spreading to nearby genes, resistant to activation induced by cytokine stimulation, and relieved only by targeted DNA demethylation. We demonstrate the portability of this technology by multiplex gene silencing, adopting different DNA binding platforms and interrogating thousands of genomic loci in different cell types, including primary T lymphocytes. Targeted epigenome editing might have broad application in research and medicine. Repurposing the ERV silencing machinery for targeted epigenetic gene silencing Hit-and-run delivery of combinations of engineered transcriptional repressors (ETRs) Inheritable and stimulation-resistant silencing of endogenous genes by DNA methylation Portable to different cell types and DNA binding platforms and amenable to multiplexing
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46
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Lau CH, Suh Y. Genome and Epigenome Editing in Mechanistic Studies of Human Aging and Aging-Related Disease. Gerontology 2016; 63:103-117. [PMID: 27974723 DOI: 10.1159/000452972] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/01/2016] [Indexed: 12/19/2022] Open
Abstract
The recent advent of genome and epigenome editing technologies has provided a new paradigm in which the landscape of the human genome and epigenome can be precisely manipulated in their native context. Genome and epigenome editing technologies can be applied to many aspects of aging research and offer the potential to develop novel therapeutics against age-related diseases. Here, we discuss the latest technological advances in the CRISPR-based genome and epigenome editing toolbox, and provide insight into how these synthetic biology tools could facilitate aging research by establishing in vitro cell and in vivo animal models to dissect genetic and epigenetic mechanisms underlying aging and age-related diseases. We discuss recent developments in the field with the aims to precisely modulate gene expression and dynamic epigenetic landscapes in a spatial and temporal manner in cellular and animal models, by complementing the CRISPR-based editing capability with conditional genetic manipulation tools including chemically inducible expression systems, optogenetics, logic gate genetic circuits, tissue-specific promoters, and the serotype-specific adeno-associated virus. We also discuss how the combined use of genome and epigenome editing tools permits investigators to uncover novel molecular pathways involved in the pathophysiology and etiology conferred by risk variants associated with aging and aging-related disease. A better understanding of the genetic and epigenetic regulatory mechanisms underlying human aging and age-related disease will significantly contribute to the developments of new therapeutic interventions for extending health span and life span, ultimately improving the quality of life in the elderly populations.
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Affiliation(s)
- Cia-Hin Lau
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA
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Abstract
Genome targeting has quickly developed as one of the most promising fields in science. By using programmable DNA-binding platforms and nucleases, scientists are now able to accurately edit the genome. These DNA-binding tools have recently also been applied to engineer the epigenome for gene expression modulation. Such epigenetic editing constructs have firmly demonstrated the causal role of epigenetics in instructing gene expression. Another focus of epigenome engineering is to understand the order of events of chromatin remodeling in gene expression regulation. Groundbreaking approaches in this field are beginning to yield novel insights into the function of individual chromatin marks in the context of maintaining cellular phenotype and regulating transient gene expression changes. This review focuses on recent advances in the field of epigenetic editing and highlights its promise for sustained gene expression reprogramming.
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Bell CG. Insights in human epigenomic dynamics through comparative primate analysis. Genomics 2016; 108:115-125. [DOI: 10.1016/j.ygeno.2016.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Revised: 08/03/2016] [Accepted: 09/29/2016] [Indexed: 12/11/2022]
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Abstract
We are entering an era of epigenome engineering. The precision manipulation of chromatin and epigenetic modifications provides new ways to interrogate their influence on genome and cell function and to harness these changes for applications. We review the design and state of epigenome editing tools, highlighting the unique regulatory properties afforded by these systems.
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Affiliation(s)
- Minhee Park
- Department of Biomedical Engineering and Biological Design Center, Boston University, Boston, MA, 02215, USA
| | - Albert J Keung
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695, USA
| | - Ahmad S Khalil
- Department of Biomedical Engineering and Biological Design Center, Boston University, Boston, MA, 02215, USA. .,Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA.
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