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Yang Z, Zhang Z, Li J, Chen W, Liu C. CRISPRlnc: a machine learning method for lncRNA-specific single-guide RNA design of CRISPR/Cas9 system. Brief Bioinform 2024; 25:bbae066. [PMID: 38426328 PMCID: PMC10905519 DOI: 10.1093/bib/bbae066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/22/2024] [Accepted: 02/03/2024] [Indexed: 03/02/2024] Open
Abstract
CRISPR/Cas9 is a promising RNA-guided genome editing technology, which consists of a Cas9 nuclease and a single-guide RNA (sgRNA). So far, a number of sgRNA prediction softwares have been developed. However, they were usually designed for protein-coding genes without considering that long non-coding RNA (lncRNA) genes may have different characteristics. In this study, we first evaluated the performances of a series of known sgRNA-designing tools in the context of both coding and non-coding datasets. Meanwhile, we analyzed the underpinnings of their varied performances on the sgRNA's specificity for lncRNA including nucleic acid sequence, genome location and editing mechanism preference. Furthermore, we introduce a support vector machine-based machine learning algorithm named CRISPRlnc, which aims to model both CRISPR knock-out (CRISPRko) and CRISPR inhibition (CRISPRi) mechanisms to predict the on-target activity of targets. CRISPRlnc combined the paired-sgRNA design and off-target analysis to achieve one-stop design of CRISPR/Cas9 sgRNAs for non-coding genes. Performance comparison on multiple datasets showed that CRISPRlnc was far superior to existing methods for both CRISPRko and CRISPRi mechanisms during the lncRNA-specific sgRNA design. To maximize the availability of CRISPRlnc, we developed a web server (http://predict.crisprlnc.cc) and made it available for download on GitHub.
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Affiliation(s)
- Zitian Yang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Yunnan Key Laboratory of Crop Wild Relatives Omics, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming 650223, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zexin Zhang
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Yunnan Key Laboratory of Crop Wild Relatives Omics, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming 650223, China
| | - Jing Li
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Yunnan Key Laboratory of Crop Wild Relatives Omics, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming 650223, China
| | - Wen Chen
- Hunan Provincial Key Laboratory of Vascular Biology and Translational Medicine, School of Medicine, Hunan University of Chinese Medicine, Changsha 410208, China
| | - Changning Liu
- CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Yunnan Key Laboratory of Crop Wild Relatives Omics, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming 650223, China
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2
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Veluchamy A, Teles K, Fischle W. CRISPR-broad: combined design of multi-targeting gRNAs and broad, multiplex target finding. Sci Rep 2023; 13:19717. [PMID: 37953351 PMCID: PMC10641073 DOI: 10.1038/s41598-023-46212-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 10/29/2023] [Indexed: 11/14/2023] Open
Abstract
In CRISPR-Cas and related nuclease-mediated genome editing, target recognition is based on guide RNAs (gRNAs) that are complementary to selected DNA regions. While single site targeting is fundamental for localized genome editing, targeting to expanded and multiple chromosome elements is desirable for various biological applications such as genome mapping and epigenome editing that make use of different fusion proteins with enzymatically dead Cas9. The current gRNA design tools are not suitable for this task, as these are optimized for defining single gRNAs for unique loci. Here, we introduce CRISPR-broad, a standalone, open-source application that defines gRNAs with multiple but specific targets in large continuous or spread regions of the genome, as defined by the user. This ability to identify multi-targeting gRNAs and corresponding multiple targetable regions in genomes is based on a novel aggregate gRNA scoring derived from on-target windows and off-target sites. Applying the new tool to the genomes of two model species, C. elegans and H. sapiens, we verified its efficiency in determining multi-targeting gRNAs and ranking potential target regions optimized for broad targeting. Further, we demonstrated the general usability of CRISPR-broad by cellular mapping of a large human genome element using dCas9 fused to green fluorescent protein.
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Affiliation(s)
- Alaguraj Veluchamy
- Bioscience Program, Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Kingdom of Saudi Arabia.
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN, USA.
| | - Kaian Teles
- Bioscience Program, Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Kingdom of Saudi Arabia
| | - Wolfgang Fischle
- Bioscience Program, Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), 23955-6900, Thuwal, Kingdom of Saudi Arabia.
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3
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Comprehensive computational analysis of epigenetic descriptors affecting CRISPR-Cas9 off-target activity. BMC Genomics 2022; 23:805. [PMID: 36474180 PMCID: PMC9724382 DOI: 10.1186/s12864-022-09012-7] [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: 04/20/2022] [Accepted: 10/17/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND A common issue in CRISPR-Cas9 genome editing is off-target activity, which prevents the widespread use of CRISPR-Cas9 in medical applications. Among other factors, primary chromatin structure and epigenetics may influence off-target activity. METHODS In this work, we utilize crisprSQL, an off-target database, to analyze the effect of 19 epigenetic descriptors on CRISPR-Cas9 off-target activity. Termed as 19 epigenetic features/scores, they consist of 6 experimental epigenetic and 13 computed nucleosome organization-related features. In terms of novel features, 15 of the epigenetic scores are newly considered. The 15 newly considered scores consist of 13 freshly computed nucleosome occupancy/positioning scores and 2 experimental features (MNase and DRIP). The other 4 existing scores are experimental features (CTCF, DNase I, H3K4me3, RRBS) commonly used in deep learning models for off-target activity prediction. For data curation, MNase was aggregated from existing experimental nucleosome occupancy data. Based on the sequence context information available in crisprSQL, we also computed nucleosome occupancy/positioning scores for off-target sites. RESULTS To investigate the relationship between the 19 epigenetic features and off-target activity, we first conducted Spearman and Pearson correlation analysis. Such analysis shows that some computed scores derived from training-based models and training-free algorithms outperform all experimental epigenetic features. Next, we evaluated the contribution of all epigenetic features in two successful machine/deep learning models which predict off-target activity. We found that some computed scores, unlike all 6 experimental features, significantly contribute to the predictions of both models. As a practical research contribution, we make the off-target dataset containing all 19 epigenetic features available to the research community. CONCLUSIONS Our comprehensive computational analysis helps the CRISPR-Cas9 community better understand the relationship between epigenetic features and CRISPR-Cas9 off-target activity.
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4
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Kretzmer C, Narasimhan RL, Lal RD, Balassi V, Ravellette J, Kotekar Manjunath AK, Koshy JJ, Viano M, Torre S, Zanda VM, Kumravat M, Saldanha KMR, Chandranpillai H, Nihad I, Zhong F, Sun Y, Gustin J, Borgschulte T, Liu J, Razafsky D. De novo assembly and annotation of the CHOZN® GS -/- genome supports high-throughput genome-scale screening. Biotechnol Bioeng 2022; 119:3632-3646. [PMID: 36073082 PMCID: PMC9825924 DOI: 10.1002/bit.28226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 07/20/2022] [Accepted: 08/28/2022] [Indexed: 01/11/2023]
Abstract
Chinese hamster ovary (CHO) cells have been used as the industry standard for the production of therapeutic monoclonal antibodies for several decades. Despite significant improvements in commercial-scale production processes and media, the CHO cell has remained largely unchanged. Due to the cost and complexity of whole-genome sequencing and gene-editing it has been difficult to obtain the tools necessary to improve the CHO cell line. With the advent of next-generation sequencing and the discovery of the CRISPR/Cas9 system it has become more cost effective to sequence and manipulate the CHO genome. Here, we provide a comprehensive de novo assembly and annotation of the CHO-K1 based CHOZN® GS-/- genome. Using this platform, we designed, built, and confirmed the functionality of a whole genome CRISPR guide RNA library that will allow the bioprocessing community to design a more robust CHO cell line leading to the production of life saving medications in a more cost-effective manner.
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Affiliation(s)
- Corey Kretzmer
- Upstream Research and Development, MilliporeSigmaSt. LouisMissouriUSA
| | - Rajagopalan Lakshmi Narasimhan
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Rahul Deva Lal
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Vincent Balassi
- Upstream Research and Development, MilliporeSigmaSt. LouisMissouriUSA
| | - James Ravellette
- Upstream Research and Development, MilliporeSigmaSt. LouisMissouriUSA
| | - Ajaya Kumar Kotekar Manjunath
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Jesvin Joy Koshy
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Marta Viano
- Istituto di Ricerche Biomediche “A. Marxer” RBM S.p.A.IvreaItaly
| | - Serena Torre
- Istituto di Ricerche Biomediche “A. Marxer” RBM S.p.A.IvreaItaly
| | - Valeria M. Zanda
- Istituto di Ricerche Biomediche “A. Marxer” RBM S.p.A.IvreaItaly
| | - Mausam Kumravat
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Keith Metelo Raul Saldanha
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Harikrishnan Chandranpillai
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Ifra Nihad
- Bioinformatics, IT R&D Applications, Merck (Sigma‐Aldrich Chemicals Pvt. Ltd., A subsidiary of Merck KGaA, Darmstadt, Germany)BangaloreIndia
| | - Fei Zhong
- Life Science Bioinformatics, IT, MilliporeSigmaSt. LouisMissouriUSA
| | - Yi Sun
- Bioinformatics, IT R&D Applications, MilliporeSigmaSt. LouisMissouriUSA
| | - Jason Gustin
- Upstream Research and Development, MilliporeSigmaSt. LouisMissouriUSA
| | | | - Jiajian Liu
- Life Science Bioinformatics, IT, MilliporeSigmaSt. LouisMissouriUSA
| | - David Razafsky
- Upstream Research and Development, MilliporeSigmaSt. LouisMissouriUSA
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5
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Zhu JJ, Cheng AW. JACKIE: Fast Enumeration of Genome-Wide Single- and Multicopy CRISPR Target Sites and Their Off-Target Numbers. CRISPR J 2022; 5:618-628. [PMID: 35830604 PMCID: PMC9527058 DOI: 10.1089/crispr.2022.0042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/15/2022] [Indexed: 11/29/2022] Open
Abstract
Zinc finger protein-, transcription activator like effector-, and CRISPR-based methods for genome and epigenome editing and imaging have provided powerful tools to investigate functions of genomes. Targeting sequence design is vital to the success of these experiments. Although existing design software mainly focus on designing target sequence for specific elements, we report here the implementation of Jackie and Albert's Comprehensive K-mer Instances Enumerator (JACKIE), a suite of software for enumerating all single- and multicopy sites in the genome that can be incorporated for genome-scale designs as well as loaded onto genome browsers alongside other tracks for convenient web-based graphic-user-interface-enabled design. We also implement fast algorithms to identify sequence neighborhoods or off-target counts of targeting sequences so that designs with low probability of off-target can be identified among millions of design sequences in reasonable time. We demonstrate the application of JACKIE-designed CRISPR site clusters for genome imaging.
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Affiliation(s)
- Jacqueline Jufen Zhu
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona, USA; University of Connecticut Health Center, Farmington, Connecticut, USA
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA; University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Albert Wu Cheng
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona, USA; University of Connecticut Health Center, Farmington, Connecticut, USA
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, USA; University of Connecticut Health Center, Farmington, Connecticut, USA
- The Jackson Laboratory Cancer Center, Bar Harbor, Maine, USA; University of Connecticut Health Center, Farmington, Connecticut, USA
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, Connecticut, USA; and University of Connecticut Health Center, Farmington, Connecticut, USA
- Institute for Systems Genomics, University of Connecticut Health Center, Farmington, Connecticut, USA
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6
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Bradford J, Chappell T, Perrin D. Rapid Whole-Genome Identification of High Quality CRISPR Guide RNAs with the Crackling Method. CRISPR J 2022; 5:410-421. [PMID: 35686976 DOI: 10.1089/crispr.2021.0102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The design of CRISPR-Cas9 guide RNAs is not trivial and is a computationally demanding task. Design tools need to identify target sequences that will maximize the likelihood of obtaining the desired cut, while minimizing off-target risk. There is a need for a tool that can meet both objectives while remaining practical to use on large genomes. In this study, we present Crackling, a new method that is more suitable for meeting these objectives. We test its performance on 12 genomes and on data from validation studies. Crackling maximizes guide efficiency by combining multiple scoring approaches. On experimental data, the guides it selects are better than those selected by others. It also incorporates Inverted Signature Slice Lists (ISSL) for faster off-target scoring. ISSL provides a gain of an order of magnitude in speed compared with other popular tools, such as Cas-OFFinder, Crisflash, and FlashFry, while preserving the same level of accuracy. Overall, this makes Crackling a faster and better method to design guide RNAs at scale. Crackling is available at https://github.com/bmds-lab/Crackling under the Berkeley Software Distribution (BSD) 3-Clause license.
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Affiliation(s)
- Jacob Bradford
- School of Computer Science, Queensland University of Technology, Brisbane, Australia
- Centre for Data Science, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Timothy Chappell
- School of Computer Science, Queensland University of Technology, Brisbane, Australia
- Centre for Data Science, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Dimitri Perrin
- School of Computer Science, Queensland University of Technology, Brisbane, Australia
- Centre for Data Science, Queensland University of Technology, Brisbane, Queensland, Australia
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7
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Konstantakos V, Nentidis A, Krithara A, Paliouras G. CRISPR-Cas9 gRNA efficiency prediction: an overview of predictive tools and the role of deep learning. Nucleic Acids Res 2022; 50:3616-3637. [PMID: 35349718 PMCID: PMC9023298 DOI: 10.1093/nar/gkac192] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 03/09/2022] [Accepted: 03/28/2022] [Indexed: 12/26/2022] Open
Abstract
The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system has become a successful and promising technology for gene-editing. To facilitate its effective application, various computational tools have been developed. These tools can assist researchers in the guide RNA (gRNA) design process by predicting cleavage efficiency and specificity and excluding undesirable targets. However, while many tools are available, assessment of their application scenarios and performance benchmarks are limited. Moreover, new deep learning tools have been explored lately for gRNA efficiency prediction, but have not been systematically evaluated. Here, we discuss the approaches that pertain to the on-target activity problem, focusing mainly on the features and computational methods they utilize. Furthermore, we evaluate these tools on independent datasets and give some suggestions for their usage. We conclude with some challenges and perspectives about future directions for CRISPR-Cas9 guide design.
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Affiliation(s)
- Vasileios Konstantakos
- Institute of Informatics and Telecommunications, NCSR Demokritos, Patr. Gregoriou E & 27 Neapoleos Str, 15341 Athens, Greece
| | - Anastasios Nentidis
- Institute of Informatics and Telecommunications, NCSR Demokritos, Patr. Gregoriou E & 27 Neapoleos Str, 15341 Athens, Greece
- School of Informatics, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Anastasia Krithara
- Institute of Informatics and Telecommunications, NCSR Demokritos, Patr. Gregoriou E & 27 Neapoleos Str, 15341 Athens, Greece
| | - Georgios Paliouras
- Institute of Informatics and Telecommunications, NCSR Demokritos, Patr. Gregoriou E & 27 Neapoleos Str, 15341 Athens, Greece
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8
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Kiryushkin AS, Ilina EL, Guseva ED, Pawlowski K, Demchenko KN. Hairy CRISPR: Genome Editing in Plants Using Hairy Root Transformation. PLANTS (BASEL, SWITZERLAND) 2021; 11:51. [PMID: 35009056 PMCID: PMC8747350 DOI: 10.3390/plants11010051] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/15/2021] [Accepted: 12/20/2021] [Indexed: 05/27/2023]
Abstract
CRISPR/Cas-mediated genome editing is a powerful tool of plant functional genomics. Hairy root transformation is a rapid and convenient approach for obtaining transgenic roots. When combined, these techniques represent a fast and effective means of studying gene function. In this review, we outline the current state of the art reached by the combination of these approaches over seven years. Additionally, we discuss the origins of different Agrobacterium rhizogenes strains that are widely used for hairy root transformation; the components of CRISPR/Cas vectors, such as the promoters that drive Cas or gRNA expression, the types of Cas nuclease, and selectable and screenable markers; and the application of CRISPR/Cas genome editing in hairy roots. The modification of the already known vector pKSE401 with the addition of the rice translational enhancer OsMac3 and the gene encoding the fluorescent protein DsRed1 is also described.
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Affiliation(s)
- Alexey S. Kiryushkin
- Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute, Russian Academy of Sciences, 197376 Saint Petersburg, Russia; (E.L.I.); (E.D.G.)
| | - Elena L. Ilina
- Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute, Russian Academy of Sciences, 197376 Saint Petersburg, Russia; (E.L.I.); (E.D.G.)
| | - Elizaveta D. Guseva
- Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute, Russian Academy of Sciences, 197376 Saint Petersburg, Russia; (E.L.I.); (E.D.G.)
| | - Katharina Pawlowski
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden
| | - Kirill N. Demchenko
- Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute, Russian Academy of Sciences, 197376 Saint Petersburg, Russia; (E.L.I.); (E.D.G.)
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9
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Hassan MM, Zhang Y, Yuan G, De K, Chen JG, Muchero W, Tuskan GA, Qi Y, Yang X. Construct design for CRISPR/Cas-based genome editing in plants. TRENDS IN PLANT SCIENCE 2021; 26:1133-1152. [PMID: 34340931 DOI: 10.1016/j.tplants.2021.06.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 06/21/2021] [Accepted: 06/24/2021] [Indexed: 05/06/2023]
Abstract
CRISPR construct design is a key step in the practice of genome editing, which includes identification of appropriate Cas proteins, design and selection of guide RNAs (gRNAs), and selection of regulatory elements to express gRNAs and Cas proteins. Here, we review the choices of CRISPR-based genome editors suited for different needs in plant genome editing applications. We consider the technical aspects of gRNA design and the associated computational tools. We also discuss strategies for the design of multiplex CRISPR constructs for high-throughput manipulation of complex biological processes or polygenic traits. We provide recommendations for different elements of CRISPR constructs and discuss the remaining challenges of CRISPR construct optimization in plant genome editing.
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Affiliation(s)
- Md Mahmudul Hassan
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Department of Genetics and Plant Breeding, Patuakhali Science and Technology University, Dumki, Patuakhali-8602, Bangladesh
| | - Yingxiao Zhang
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742, USA
| | - Guoliang Yuan
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Kuntal De
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Jin-Gui Chen
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Wellington Muchero
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Gerald A Tuskan
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Yiping Qi
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742, USA; Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA.
| | - Xiaohan Yang
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; The Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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10
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Peng H, Zheng Y, Zhao Z, Li J. Multigene editing: current approaches and beyond. Brief Bioinform 2021; 22:bbaa396. [PMID: 33428725 DOI: 10.1093/bib/bbaa396] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/15/2020] [Accepted: 12/03/2020] [Indexed: 11/14/2022] Open
Abstract
CRISPR/Cas9 multigene editing is an active and widely studied topic in the fields of biomedicine and biology. It involves a simultaneous participation of multiple single-guide RNAs (sgRNAs) to edit multiple target genes in a way that each gene is edited by one of these sgRNAs. There are possibly numerous sgRNA candidates capable of on-target editing on each of these genes with various efficiencies. Meanwhile, each of these sgRNA candidates may cause unwanted off-target editing at many other genes. Therefore, selection optimization of these multiple sgRNAs is demanded so as to minimize the number of sgRNAs and thus reduce the collective negative effects caused by the off-target editing. This survey reviews wet-laboratory approaches to the implementation of multigene editing and their needs of computational tools for better design. We found that though off-target editing is unavoidable during the gene editing, those disfavored cuttings by some target genes' sgRNAs can potentially become on-target editing sites for some other genes of interests. This off-to-on role conversion is beneficial to optimize the sgRNA selection in multigene editing. We present a preference cutting score to assess those beneficial off-target cutting sites, which have a few mismatches with their host genes' on-target editing sites. These potential sgRNAs can be prioritized for recommendation via ranking their on-target average cutting efficiency, the total off-target site number and their average preference cutting score. We also present case studies on cancer-associated genes to demonstrate tremendous usefulness of the new method.
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Affiliation(s)
- Hui Peng
- Data Science Institute, University of Technology Sydney, PO Box 123, Ultimo, NSW 2007, Australia
- School of Computing, National University of Singapore, 13 Computing Drive, 117417, Singapore
| | - Yi Zheng
- Data Science Institute, University of Technology Sydney, PO Box 123, Ultimo, NSW 2007, Australia
| | - Zhixun Zhao
- Data Science Institute, University of Technology Sydney, PO Box 123, Ultimo, NSW 2007, Australia
| | - Jinyan Li
- Data Science Institute, University of Technology Sydney, PO Box 123, Ultimo, NSW 2007, Australia
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11
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Choi SH, Lee MH, Jin DM, Ju SJ, Ahn WS, Jie EY, Lee JM, Lee J, Kim CY, Kim SW. TSA Promotes CRISPR/Cas9 Editing Efficiency and Expression of Cell Division-Related Genes from Plant Protoplasts. Int J Mol Sci 2021; 22:7817. [PMID: 34360584 PMCID: PMC8346083 DOI: 10.3390/ijms22157817] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 12/15/2022] Open
Abstract
Trichostatin A (TSA) is a representative histone deacetylase (HDAC) inhibitor that modulates epigenetic gene expression by regulation of chromatin remodeling in cells. To investigate whether the regulation of chromatin de-condensation by TSA can affect the increase in the efficiency of Cas9 protein-gRNA ribonucleoprotein (RNP) indel formation from plant cells, genome editing efficiency using lettuce and tobacco protoplasts was examined after several concentrations of TSA treatments (0, 0.1, 1 and 10 μM). RNP delivery from protoplasts was conducted by conventional polyethylene glycol (PEG) transfection protocols. Interestingly, the indel frequency of the SOC1 gene from TSA treatments was about 3.3 to 3.8 times higher than DMSO treatment in lettuce protoplasts. The TSA-mediated increase of indel frequency of the SOC1 gene in lettuce protoplasts occurred in a concentration-dependent manner, although there was not much difference. Similar to lettuce, TSA also increased the indel frequency by 1.5 to 1.8 times in a concentration-dependent manner during PDS genome editing using tobacco protoplasts. The MNase test clearly showed that chromatin accessibility with TSA treatments was higher than that of DMSO treatment. Additionally, TSA treatment significantly increased the level of histone H3 and H4 acetylation from lettuce protoplasts. The qRT-PCR analysis showed that expression of cell division-related genes (LsCYCD1-1, LsCYCD3-2, LsCYCD6-1, and LsCYCU4-1) was increased by TSA treatment. These findings could contribute to increasing the efficiency of CRISPR/Cas9-mediated genome editing. Furthermore, this could be applied for the development of useful genome-edited crops using the CRISPR/Cas9 system with plant protoplasts.
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Affiliation(s)
- Seung Hee Choi
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
| | - Myoung Hui Lee
- National Institute of Crop Science, RDA, Wanju 55365, Korea;
| | - Da Mon Jin
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Su Ji Ju
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
- Department of Applied Plant Science, Chonnam National University, Gwangju 61186, Korea
| | - Woo Seok Ahn
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Eun Yee Jie
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
| | - Ji Min Lee
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
| | - Jiyoung Lee
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
| | - Cha Young Kim
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
| | - Suk Weon Kim
- Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsingil, Jeongeup-si 56212, Korea; (S.H.C.); (D.M.J.); (S.J.J.); (W.S.A.); (E.Y.J.); (J.M.L.); (J.L.); (C.Y.K.)
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12
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Rodríguez TC, Dadafarin S, Pratt HE, Liu P, Amrani N, Zhu LJ. Genome-wide detection and analysis of CRISPR-Cas off-targets. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 181:31-43. [PMID: 34127199 DOI: 10.1016/bs.pmbts.2021.01.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The clustered, regularly interspersed, short palindromic repeats (CRISPR) technology is revolutionizing biological studies and holds tremendous promise for treating human diseases. However, a significant limitation of this technology is that modifications can occur on off-target sites lacking perfect complementarity to the single guide RNA (sgRNA) or canonical protospacer-adjacent motif (PAM) sequence. Several in vivo and in vitro genome-wide off-target profiling approaches have been developed to inform on the fidelity of gene editing. Of these, GUIDE-seq has become one of the most widely adopted and reproducible methods. To allow users to easily analyze GUIDE-seq data generated on any sequencing platform, we developed an open-source pipeline, GS-Preprocess, that takes standard base-call output in bcl format and generate all required input data for off-target identification using bioconductor package GUIDEseq for off-target identification. Furthermore, we created a Docker image with GS-Proprocess, GUIDE-seq, and all its R and system dependencies already installed. The bundled pipeline will empower end users to streamline the analysis of GUIDE-seq data and motivate their use of higher throughput sequencing with increased multiplexing for GUIDE-seq experiments.
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Affiliation(s)
- Tomás C Rodríguez
- University of Massachusetts Medical School Medical Scientist Training Program, Worcester, MA, United States; RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, United States.
| | - Sina Dadafarin
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, United States; Department of Microbiology and Immunology, New York Medical College, Valhalla, NY, United States
| | - Henry E Pratt
- University of Massachusetts Medical School Medical Scientist Training Program, Worcester, MA, United States; Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA, United States
| | - PengPeng Liu
- Department of Molecular, Cell and Cancer Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, United States
| | - Nadia Amrani
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, United States
| | - Lihua Julie Zhu
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA, United States; Department of Molecular, Cell and Cancer Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, United States.
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13
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Rahman MM, Tollefsbol TO. Targeting cancer epigenetics with CRISPR-dCAS9: Principles and prospects. Methods 2021; 187:77-91. [PMID: 32315755 PMCID: PMC7572534 DOI: 10.1016/j.ymeth.2020.04.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/15/2020] [Accepted: 04/15/2020] [Indexed: 12/11/2022] Open
Abstract
Cancer therapeutics is an ever-evolving field due to incessant demands for effective and precise treatment options. Over the last few decades, cancer treatment strategies have shifted somewhat from surgery to targeted precision medicine. CRISPR-dCas9 is an emerging version of precision cancer therapy that has been adapted from the prokaryotic CRISPR-Cas system. Once ligated to epigenetic effectors (EE), CRISPR-dCas9 can function as an epigenetic editing tool and CRISPR-dCas9-EE complexes could be exploited to alter cancerous epigenetic features associated with different cancer hallmarks. In this article, we discuss the rationale of epigenetic editing as a therapeutic strategy against cancer. We also outline how sgRNA-dCas9 was derived from the CRISPR-Cas system. In addition, the current status of sgRNA-dCas9 use (in vivo and in vitro) in cancer is updated with a molecular illustration of CRISPR-dCas9-mediated epigenetic and transcriptional modulation. As sgRNA-dCas9 is still at the developmental phase, challenges are inherent to its use. We evaluate major challenges in targeting cancer with sgRNA-dCas9 such as off-target effects, lack of sgRNA designing rubrics, target site selection dilemmas and deficient sgRNA-dCas9 delivery systems. Finally, we appraise the sgRNA-dCas9 as a prospective cancer therapeutic by summarizing ongoing improvements of sgRNA-dCas9 methodology.
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Affiliation(s)
- Mohammad Mijanur Rahman
- Department of Biology, University of Alabama at Birmingham, 1300 University Boulevard, Birmingham, AL 35294, USA.
| | - Trygve O Tollefsbol
- Department of Biology, University of Alabama at Birmingham, 1300 University Boulevard, Birmingham, AL 35294, USA; Comprehensive Center for Healthy Aging, University of Alabama Birmingham, 1530 3rd Avenue South, Birmingham, AL 35294, USA; Comprehensive Cancer Center, University of Alabama Birmingham, 1802 6th Avenue South, Birmingham, AL 35294, USA; Nutrition Obesity Research Center, University of Alabama Birmingham, 1675 University Boulevard, Birmingham, AL 35294, USA; Comprehensive Diabetes Center, University of Alabama Birmingham, 1825 University Boulevard, Birmingham, AL 35294, USA.
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14
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Mukhopadhyay S, Bhutia SK. Trends in CRISPR-Cas9 technology application in cancer. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 178:175-192. [PMID: 33685596 DOI: 10.1016/bs.pmbts.2020.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The evolution of the CRISPR-Cas9 technology in cancer research has tremendous potential to shape the future of oncology. Although this gene-editing tool's pre-clinical progress is into its nascent stage, there are many unanswered questions regarding health benefits and therapy precision using CRISPR. The application of CRISPR is highly specific, economically sustainable, and is a high throughput technique, but on the other hand, its application involves measured risk of countering the toxic immune response of Cas protein, off-target effects, limitation of delivering the edited cells back into cancer patients. The current chapter highlights the possibilities and perils of the present-day CRISPR engineering in cancer that should highlight CRISPR translation to therapy.
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Affiliation(s)
- Subhadip Mukhopadhyay
- Department of Radiation Oncology, Laura and Isaac Perlmutter Cancer Center, NYU Medical School, New York, NY, United States.
| | - Sujit Kumar Bhutia
- Department of Life Science, National Institute of Technology, Rourkela, Odisha, India.
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15
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Kujoth GC, Sullivan TD, Klein BS. Gene Editing in Dimorphic Fungi Using CRISPR/Cas9. CURRENT PROTOCOLS IN MICROBIOLOGY 2020; 59:e132. [PMID: 33315302 PMCID: PMC7783865 DOI: 10.1002/cpmc.132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Dimorphic fungi in the genera Blastomyces, Histoplasma, Coccidioides, and Paracoccidioides are important human pathogens that affect human health in many countries throughout the world. Understanding the biology of these fungi is important for the development of effective treatments and vaccines. Gene editing is a critically important tool for research into these organisms. In recent years, gene targeting approaches employing RNA-guided DNA nucleases, such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated nuclease 9 (Cas9), have exploded in popularity. Here, we provide a detailed description of the steps involved in applying CRISPR/Cas9 technology to dimorphic fungi, with Blastomyces dermatitidis in particular as our model fungal pathogen. We discuss the design and construction of single guide RNA and Cas9-expressing targeting vectors (including multiplexed vectors) as well as introduction of these plasmids into Blastomyces using Agrobacterium-mediated transformation. Finally, we cover the outcomes that may be expected in terms of gene-editing efficiency and types of gene alterations produced. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Construction of CRISPR/Cas9 targeting vectors Support Protocol 1: Choosing protospacers in the target gene Basic Protocol 2: Agrobacterium-mediated transformation of Blastomyces Support Protocol 2: Preparation of electrocompetent Agrobacterium Support Protocol 3: Preparation and recovery of Blastomyces frozen stocks.
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Affiliation(s)
- Gregory C. Kujoth
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706
| | - Thomas D. Sullivan
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706
| | - Bruce S. Klein
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706
- Department of Medical Microbiology & Immunology, University of Wisconsin-Madison, Madison, WI 53706
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16
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Zhang L, Rube HT, Vakulskas CA, Behlke MA, Bussemaker HJ, Pufall MA. Systematic in vitro profiling of off-target affinity, cleavage and efficiency for CRISPR enzymes. Nucleic Acids Res 2020; 48:5037-5053. [PMID: 32315032 PMCID: PMC7229833 DOI: 10.1093/nar/gkaa231] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 03/06/2020] [Accepted: 03/27/2020] [Indexed: 12/14/2022] Open
Abstract
CRISPR RNA-guided endonucleases (RGEs) cut or direct activities to specific genomic loci, yet each has off-target activities that are often unpredictable. We developed a pair of simple in vitro assays to systematically measure the DNA-binding specificity (Spec-seq), catalytic activity specificity (SEAM-seq) and cleavage efficiency of RGEs. By separately quantifying binding and cleavage specificity, Spec/SEAM-seq provides detailed mechanistic insight into off-target activity. Feature-based models generated from Spec/SEAM-seq data for SpCas9 were consistent with previous reports of its in vitro and in vivo specificity, validating the approach. Spec/SEAM-seq is also useful for profiling less-well characterized RGEs. Application to an engineered SpCas9, HiFi-SpCas9, indicated that its enhanced target discrimination can be attributed to cleavage rather than binding specificity. The ortholog ScCas9, on the other hand, derives specificity from binding to an extended PAM. The decreased off-target activity of AsCas12a (Cpf1) appears to be primarily driven by DNA-binding specificity. Finally, we performed the first characterization of CasX specificity, revealing an all-or-nothing mechanism where mismatches can be bound, but not cleaved. Together, these applications establish Spec/SEAM-seq as an accessible method to rapidly and reliably evaluate the specificity of RGEs, Cas::gRNA pairs, and gain insight into the mechanism and thermodynamics of target discrimination.
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Affiliation(s)
- Liyang Zhang
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Coralville, IA 52241, USA.,Integrated DNA Technologies, Inc., 1710 Commercial Park, Coralville, IA 52241, USA
| | - H Tomas Rube
- Department of Bioengineering, University of California, Merced, New York, NY 10027, USA.,Department of Biological Sciences, Columbia University, New York, NY 10027, USA.,Department of Systems Biology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | | | - Mark A Behlke
- Integrated DNA Technologies, Inc., 1710 Commercial Park, Coralville, IA 52241, USA
| | - Harmen J Bussemaker
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.,Department of Systems Biology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Miles A Pufall
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Coralville, IA 52241, USA
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17
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Rousset F, Bikard D. CRISPR screens in the era of microbiomes. Curr Opin Microbiol 2020; 57:70-77. [PMID: 32858412 DOI: 10.1016/j.mib.2020.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 07/13/2020] [Accepted: 07/17/2020] [Indexed: 02/07/2023]
Abstract
Recent advances in genomics have uncovered the tremendous diversity and richness of microbial ecosystems. New functional genomics methods are now needed to probe gene function in high-throughput and provide mechanistic insights. Here, we review how the CRISPR toolbox can be used to inactivate, repress or overexpress genes in a sequence-specific manner and how this offers diverse attractive solutions to identify gene function in high-throughput. Developed both in eukaryotes and prokaryotes, CRISPR screening technologies have already provided meaningful insights in microbiology and host-pathogen interactions. In the era of microbiomes, the versatility and the functional diversity of CRISPR-derived tools has the potential to significantly improve our understanding of microbial communities and their interaction with the host.
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Affiliation(s)
- François Rousset
- Synthetic Biology Group, Microbiology Department, Institut Pasteur, Paris, France; Sorbonne Université, Collège Doctoral, F-75005 Paris, France
| | - David Bikard
- Synthetic Biology Group, Microbiology Department, Institut Pasteur, Paris, France.
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18
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Chamseddin BH, Le LQ. Management of cutaneous neurofibroma: current therapy and future directions. Neurooncol Adv 2020; 2:i107-i116. [PMID: 32642736 PMCID: PMC7317049 DOI: 10.1093/noajnl/vdz034] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Neurofibromatosis type 1 (NF1) is a life-long neurocutaneous disorder characterized by a predisposition to tumor development, including cutaneous neurofibroma (cNF), the hallmark of the disease. cNF is a histologically benign, multicellular tumor formed in virtually most individuals with NF1. It is considered the most burdensome feature of the disorder due to their physical discomfort, cosmetically disfiguring appearance, and psychosocial burden. Management of cNF remains a challenge in the medical field. Effective medicinal treatment for cNF does not exist at this time. Trials aimed at targeting individual components of the neoplasm such as mast cells with Ketotifen have not shown much success. Physical removal or destruction has been the mainstay of therapy. Surgical removal gives excellent cosmetic results, but risk in general anesthesia may require trained specialists. Destructive laser such as CO2 laser is effective in treating hundreds of tumors at one time but has high risk of scarring hypopigmentation or hyperpigmentation that alter cosmetic outcomes. A robust, low-risk surgical technique has been developed, which may be performed in clinic using traditional biopsy tools that may be more accessible to NF1 patients worldwide than contemporary techniques including Er:YAG or Nd:YAG laser. In this review, specific recommendations for management of cNFs are made based on symptoms, clinical expertise, and available resources. Additionally, antiproliferative agents aimed at stimulating cellular quiescence are explored.
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Affiliation(s)
- Bahir H Chamseddin
- Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Lu Q Le
- Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, Texas
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas
- Neurofibromatosis Clinic, University of Texas Southwestern Medical Center, Dallas, Texas
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19
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Beeber D, Chain FJ. crispRdesignR: A Versatile Guide RNA Design Package in R for CRISPR/Cas9 Applications. J Genomics 2020; 8:62-70. [PMID: 32494309 PMCID: PMC7256011 DOI: 10.7150/jgen.41196] [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: 10/15/2019] [Accepted: 03/27/2020] [Indexed: 11/16/2022] Open
Abstract
The success of CRISPR/Cas9 gene editing applications relies on the efficiency of the single guide RNA (sgRNA) used in conjunction with the Cas9 protein. Current sgRNA design software vary in the details they provide on sgRNA sequence efficiency and usually limit organism choice to a list of developer-selected species. The crispRdesignR package aims to address these limitations by providing comprehensive sequence features of the generated sgRNAs in a single program, which allows users to predict sgRNA efficiency and design sgRNA sequences for systems that currently do not have optimized efficiency scoring methods. crispRdesignR reports extensive information on all designed sgRNA sequences with robust off-target calling and annotation and can be run in a user-friendly graphical interface. The crispRdesignR package is implemented in R and has fully editable code for specialized purposes including sgRNA design in user-provided genomes. The package is platform independent and extendable, with its source code and documentation freely available at https://github.com/dylanbeeber/crispRdesignR.
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Affiliation(s)
- Dylan Beeber
- Department of Biological Sciences, University of Massachusetts Lowell, 1 University Ave., Lowell, 01852 USA
| | - Frédéric Jj Chain
- Department of Biological Sciences, University of Massachusetts Lowell, 1 University Ave., Lowell, 01852 USA
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20
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Bradford J, Perrin D. Improving CRISPR guide design with consensus approaches. BMC Genomics 2019; 20:931. [PMID: 31874627 PMCID: PMC6929336 DOI: 10.1186/s12864-019-6291-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 11/14/2019] [Indexed: 12/13/2022] Open
Abstract
Background CRISPR-based systems are playing an important role in modern genome engineering. A large number of computational methods have been developed to assist in the identification of suitable guides. However, there is only limited overlap between the guides that each tool identifies. This can motivate further development, but also raises the question of whether it is possible to combine existing tools to improve guide design. Results We considered nine leading guide design tools, and their output when tested using two sets of guides for which experimental validation data is available. We found that consensus approaches were able to outperform individual tools. The best performance (with a precision of up to 0.912) was obtained when combining four of the tools and accepting all guides selected by at least three of them. Conclusions These results can be used to improve CRISPR-based studies, but also to guide further tool development. However, they only provide a short-term solution as the time and computational resources required to run four tools may be impractical in certain applications.
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Affiliation(s)
- Jacob Bradford
- School of Electrical Engineering and Computer Science, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia
| | - Dimitri Perrin
- School of Electrical Engineering and Computer Science, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia.
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