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Wu WY, Mohanraju P, Liao C, Adiego-Pérez B, Creutzburg SCA, Makarova KS, Keessen K, Lindeboom TA, Khan TS, Prinsen S, Joosten R, Yan WX, Migur A, Laffeber C, Scott DA, Lebbink JHG, Koonin EV, Beisel CL, van der Oost J. The miniature CRISPR-Cas12m effector binds DNA to block transcription. Mol Cell 2022; 82:4487-4502.e7. [PMID: 36427491 DOI: 10.1016/j.molcel.2022.11.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 08/01/2022] [Accepted: 10/31/2022] [Indexed: 11/27/2022]
Abstract
CRISPR-Cas are prokaryotic adaptive immune systems. Cas nucleases generally use CRISPR-derived RNA guides to specifically bind and cleave DNA or RNA targets. Here, we describe the experimental characterization of a bacterial CRISPR effector protein Cas12m representing subtype V-M. Despite being less than half the size of Cas12a, Cas12m catalyzes auto-processing of a crRNA guide, recognizes a 5'-TTN' protospacer-adjacent motif (PAM), and stably binds a guide-complementary double-stranded DNA (dsDNA). Cas12m has a RuvC domain with a non-canonical catalytic site and accordingly is incapable of guide-dependent cleavage of target nucleic acids. Despite lacking target cleavage activity, the high binding affinity of Cas12m to dsDNA targets allows for interference as demonstrated by its ability to protect bacteria against invading plasmids through silencing invader transcription and/or replication. Based on these molecular features, we repurposed Cas12m by fusing it to a cytidine deaminase that resulted in base editing within a distinct window.
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Affiliation(s)
- Wen Y Wu
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands.
| | - Prarthana Mohanraju
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Chunyu Liao
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz-Centre for Infection Research (HZI), 97080 Würzburg, Germany
| | - Belén Adiego-Pérez
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Sjoerd C A Creutzburg
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Kira S Makarova
- National Centre for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Karlijn Keessen
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Timon A Lindeboom
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Tahseen S Khan
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Stijn Prinsen
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Rob Joosten
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | | | - Anzhela Migur
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz-Centre for Infection Research (HZI), 97080 Würzburg, Germany
| | - Charlie Laffeber
- Department of Molecular Genetics, Oncode Institute, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3000 CA Rotterdam, the Netherlands
| | | | - Joyce H G Lebbink
- Department of Molecular Genetics, Oncode Institute, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3000 CA Rotterdam, the Netherlands; Department of Radiation Oncology, Erasmus University Medical Center, 3000 CA Rotterdam, the Netherlands
| | - Eugene V Koonin
- National Centre for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Chase L Beisel
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz-Centre for Infection Research (HZI), 97080 Würzburg, Germany; Medical Faculty, University of Würzburg, 97080 Würzburg, Germany
| | - John van der Oost
- Laboratory of Microbiology, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands.
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2
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Li D, Li P, Peng M, Zhao X, Jiang X, Wang D, Yuan Y, Guo Q, Wang M, Xu X, Wang M. Transmission barrier of the blaKPC plasmid mediated by type I restriction-modification systems in Escherichia coli. J Antimicrob Chemother 2022; 77:952-956. [PMID: 35040978 DOI: 10.1093/jac/dkab489] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 12/06/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Transportation of carbapenem-resistant plasmids contributes to carbapenem resistance in Gram-negative bacteria. KPC enzymes are the most clinically important enzymes among carbapenem-resistant Klebsiella pneumoniae, whereas the rate of blaKPC in Escherichia coli is low. The CRISPR-Cas system and restriction-modification system (R-M system) in bacteria defend against invading genomes. Currently, the role of the immune systems in the low rate of KPC-producing E. coli remains unclear. OBJECTIVES We investigated the relationship between immune systems and the low detection rate of blaKPC in E. coli. METHODS We searched for blaKPC among 1039 E. coli whole genomes available in GenBank using nucleotide BLAST. CRISPR-Cas systems and the R-M system were detected in all strains having the ST as blaKPC-positive strains. Nucleotide BLAST was used to search for protospacers on blaKPC plasmids. A conjugation assay was performed to determine whether the R-M system influences the acquisition of blaKPC plasmids by E. coli. RESULTS ST131 was the dominant ST of KPC-producing E. coli and IncN was the main plasmid type (12/32). CRISPR-Cas systems were frequently present in E. coli carrying blaKPC. Furthermore, CRISPR-Cas systems in E. coli didn't target plasmids with blaKPC. Type I R-M systems were rare in KPC-producing E. coli, but significantly over-represented in KPC-negative strains. E. coli DH5α with hsdR deletion accepted blaKPC-carrying plasmids, whereas those with hsdR complementation impeded blaKPC-carrying plasmid conjugation. CONCLUSIONS Horizontal transmission of blaKPC occurs among E. coli. The type I R-M system is associated with the defence against blaKPC plasmid transport into E. coli.
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Affiliation(s)
- Dan Li
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Pei Li
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Mingjia Peng
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Xiaoyu Zhao
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Xiaoying Jiang
- The First Department of Critical Care Medicine, Gansu Provincial Hospital, Gansu, People's Republic of China
| | - Dongliang Wang
- The First Department of Critical Care Medicine, Gansu Provincial Hospital, Gansu, People's Republic of China
| | - Yuan Yuan
- The First Department of Critical Care Medicine, Gansu Provincial Hospital, Gansu, People's Republic of China
| | - Qinglan Guo
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Minghua Wang
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Xiaogang Xu
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
| | - Minggui Wang
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, People's Republic of China.,Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, People's Republic of China
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3
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Devi V, Harjai K, Chhibber S. Self-targeting spacers in CRISPR-array: Accidental occurrence or evolutionarily conserved phenomenon. J Basic Microbiol 2021; 62:4-12. [PMID: 34904260 DOI: 10.1002/jobm.202100514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/18/2021] [Accepted: 11/27/2021] [Indexed: 11/12/2022]
Abstract
In recent years, a tremendous amount of inquisitiveness among scientists in the clustered regularly interspaced short palindrome repeats (CRISPR)-CRISPR-associated proteins (Cas) has led to many studies to delineate their exact role in prokaryotes. CRISPR-Cas is an adaptive immune system that protects prokaryotes from phages and mobile genetic elements. It incorporates small DNA fragment of the invader in the CRISPR-array and protects the host from future invasion by them. In a few instances, the CRISPR-array also incorporates self-targeting spacers, most likely by accident or leaky incorporation. A significant number of spacers are found to match with the host genes across the species; however, self-targeting spacers have not been investigated in detail in most of the organisms. The presence of self-targeting spacers in the CRISPR-array led to speculation that the CRISPR-Cas system has a lot more to offer than just being the conventional adaptive immune system. It has been implicated in gene regulation and autoimmunity more or less equally. In this review, an attempt has been made to understand self-targeting spacers in the context of gene regulation, autoimmunity, and its avoidance strategies.
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Affiliation(s)
- Veena Devi
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Kusum Harjai
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Sanjay Chhibber
- Department of Microbiology, Panjab University, Chandigarh, India
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4
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Ratner HK, Weiss DS. crRNA complementarity shifts endogenous CRISPR-Cas systems between transcriptional repression and DNA defense. RNA Biol 2021; 18:1560-1573. [PMID: 33733999 PMCID: PMC8583161 DOI: 10.1080/15476286.2021.1878335] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/10/2021] [Accepted: 01/13/2021] [Indexed: 12/26/2022] Open
Abstract
CRISPR-Cas systems are prokaryotic adaptive immune systems that recognize and cleave nucleic acid targets using small RNAs called CRISPR RNAs (crRNAs) to guide Cas protein(s). There is increasing evidence for the broader endogenous roles of these systems. The CRISPR-Cas9 system of Francisella novicida also represses endogenous transcription using a non-canonical small RNA (scaRNA). We examined whether the crRNAs of the native F. novicida CRISPR-Cas systems, Cas12a and Cas9, can guide transcriptional repression. Both systems repressed mRNA transcript levels when crRNA-target complementarity was limited, and led to target cleavage with extended complementarity. Using these parameters we engineered the CRISPR array of Cas12a to guide the transcriptional repression of a new and endogenous target. Since the majority of crRNA targets remain unidentified, this work suggests that a re-analysis of crRNAs for endogenous targets with limited complementarity could reveal new, diverse regulatory roles for CRISPR-Cas systems in prokaryotic biology.
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Affiliation(s)
- Hannah K. Ratner
- Microbiology and Molecular Genetics Program, Emory University, Atlanta, GA, USA
- Emory Vaccine Center, Emory University, Atlanta, GA, USA
- Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
| | - David S. Weiss
- Emory Vaccine Center, Emory University, Atlanta, GA, USA
- Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
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5
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Olonade I, van Zyl LJ, Trindade M. Genomic Characterization of a Prophage, Smhb1, That Infects Salinivibrio kushneri BNH Isolated from a Namib Desert Saline Spring. Microorganisms 2021; 9:2043. [PMID: 34683373 PMCID: PMC8537503 DOI: 10.3390/microorganisms9102043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 08/27/2021] [Accepted: 08/28/2021] [Indexed: 11/29/2022] Open
Abstract
Recent years have seen the classification and reclassification of many viruses related to the model enterobacterial phage P2. Here, we report the identification of a prophage (Smhb1) that infects Salinivibrio kushneri BNH isolated from a Namib Desert salt pan (playa). Analysis of the genome revealed that it showed the greatest similarity to P2-like phages that infect Vibrio species and showed no relation to any of the previously described Salinivibrio-infecting phages. Despite being distantly related to these Vibrio infecting phages and sharing the same modular gene arrangement as seen in most P2-like viruses, the nucleotide identity to its closest relatives suggest that, for now, Smhb1 is the lone member of the Peduovirus genus Playavirus. Although host range testing was not extensive and no secondary host could be identified for Smhb1, genomic evidence suggests that the phage is capable of infecting other Salinivibrio species, including Salinivibrio proteolyticus DV isolated from the same playa. Taken together, the analysis presented here demonstrates how adaptable the P2 phage model can be.
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Affiliation(s)
| | - Leonardo Joaquim van Zyl
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Bellville, Cape Town 7535, South Africa; (I.O.); (M.T.)
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6
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Kirtania P, Hódi B, Mallick I, Vass IZ, Fehér T, Vass I, Kós PB. A single plasmid based CRISPR interference in Synechocystis 6803 - A proof of concept. PLoS One 2019; 14:e0225375. [PMID: 31770415 PMCID: PMC6879144 DOI: 10.1371/journal.pone.0225375] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 11/02/2019] [Indexed: 11/20/2022] Open
Abstract
We developed a simple method to apply CRISPR interference by modifying an existing plasmid pCRISPathBrick containing the native S. pyogenes CRISPR assembly for Synechocystis PCC6803 and named it pCRPB1010. The technique presented here using deadCas9 is easier to implement for gene silencing in Synechocystis PCC6803 than other existing techniques as it circumvents the genome integration and segregation steps thereby significantly shortens the construction of the mutant strains. We executed CRISPR interference against well characterized photosynthetic genes to get a clear phenotype to validate the potential of pCRPB1010 and presented the work as a “proof of concept”. Targeting the non-template strand of psbO gene resulted in decreased amount of PsbO and 50% decrease in oxygen evolution rate. Targeting the template strand of psbA2 and psbA3 genes encoding the D1 subunit of photosystem II (PSII) using a single spacer against the common sequence span of the two genes, resulted in full inhibition of both genes, complete abolition of D1 protein synthesis, complete loss of oxygen evolution as well as photoautotrophic growth arrest. This is the first report of a single plasmid based, completely lesion free and episomal expression and execution of CRISPR interference in Synechocystis PCC6803.
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Affiliation(s)
- Prithwiraj Kirtania
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.,Doctoral School of Biology, University of Szeged, Szeged, Hungary
| | - Barbara Hódi
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.,Doctoral School of Biology, University of Szeged, Szeged, Hungary
| | - Ivy Mallick
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - István Zoltan Vass
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Tamás Fehér
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Imre Vass
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Peter B Kós
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.,Department of Biotechnology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
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7
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Monteiro LMO, Arruda LM, Sanches-Medeiros A, Martins-Santana L, Alves LDF, Defelipe L, Turjanski AG, Guazzaroni ME, de Lorenzo V, Silva-Rocha R. Reverse Engineering of an Aspirin-Responsive Transcriptional Regulator in Escherichia coli. ACS Synth Biol 2019; 8:1890-1900. [PMID: 31362496 DOI: 10.1021/acssynbio.9b00191] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Bacterial transcription factors (TFs) are key devices for the engineering of complex circuits in many biotechnological applications, yet there are few well-characterized inducer-responsive TFs that could be used in the context of an animal or human host. We have deciphered the inducer recognition mechanism of two AraC/XylS regulators from Pseudomonas putida (BenR and XylS) for creating a novel expression system responsive to acetyl salicylate (i.e., aspirin). Using protein homology modeling and molecular docking with the cognate inducer benzoate and a suite of chemical analogues, we identified the conserved binding pocket of BenR and XylS. By means of site-directed mutagenesis, we identified a single amino acid position required for efficient inducer recognition and transcriptional activation. Whereas this modification in BenR abolishes protein activity, in XylS, it increases the response to several inducers, including acetyl salicylic acid, to levels close to those achieved by the canonical inducer. Moreover, by constructing chimeric proteins with swapped N-terminal domains, we created novel regulators with mixed promoter and inducer recognition profiles. As a result, a collection of engineered TFs was generated with an enhanced response to benzoate, 3-methylbenzoate, 2-methylbenzoate, 4-methylbenzoate, salicylic acid, aspirin, and acetylsalicylic acid molecules for eliciting gene expression in E. coli.
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Affiliation(s)
| | - Letı́cia Magalhães Arruda
- Cell and Molecular Biology Department, FMRP − University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - Ananda Sanches-Medeiros
- Cell and Molecular Biology Department, FMRP − University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - Leonardo Martins-Santana
- Cell and Molecular Biology Department, FMRP − University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - Luana de Fátima Alves
- Biology Department, FFCLRP − University of São Paulo, Ribeirão Preto, São Paulo 14040-901, Brazil
| | - Lucas Defelipe
- Departamento de Quı́mica Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina
- IQUIBICEN/UBA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina
| | - Adrian Gustavo Turjanski
- Departamento de Quı́mica Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina
- IQUIBICEN/UBA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina
| | | | - Vı́ctor de Lorenzo
- Systems Biology Program, National Center of Biotechnology − CSIC, Madrid 28049, Spain
| | - Rafael Silva-Rocha
- Cell and Molecular Biology Department, FMRP − University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
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8
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Natural tuning of restriction endonuclease synthesis by cluster of rare arginine codons. Sci Rep 2019; 9:5808. [PMID: 30967604 PMCID: PMC6456624 DOI: 10.1038/s41598-019-42311-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/28/2019] [Indexed: 01/21/2023] Open
Abstract
Restriction–modification (R-M) systems are highly widespread among bacteria and archaea, and they appear to play a pivotal role in modulating horizontal gene transfer, as well as in protecting the host organism against viruses and other invasive DNA particles. Type II R-M systems specify two independent enzymes: a restriction endonuclease (REase) and protective DNA methyltransferase (MTase). If the cell is to survive, the counteracting activities as toxin and antitoxin, must be finely balanced in vivo. The molecular basis of this regulatory process remains unclear and current searches for regulatory elements in R-M modules are focused mainly at the transcription step. In this report, we show new aspects of REase control that are linked to translation. We used the EcoVIII R-M system as a model. Both, the REase and MTase genes for this R-M system contain an unusually high number of rare arginine codons (AGA and AGG) when compared to the rest of the E. coli K-12 genome. Clusters of these codons near the N-terminus of the REase greatly affect the translational efficiency. Changing these to higher frequency codons for E. coli (CGC) improves the REase synthesis, making the R-M system more potent to defend its host against bacteriophages. However, this improved efficiency in synthesis reduces host fitness due to increased autorestriction. We hypothesize that expression of the endonuclease gene can be modulated depending on the host genetic context and we propose a novel post-transcriptional mode of R–M system regulation that alleviates the potential lethal action of the restriction enzyme.
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9
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Donohoue PD, Barrangou R, May AP. Advances in Industrial Biotechnology Using CRISPR-Cas Systems. Trends Biotechnol 2018; 36:134-146. [PMID: 28778606 DOI: 10.1016/j.tibtech.2017.07.007] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 07/11/2017] [Accepted: 07/12/2017] [Indexed: 12/14/2022]
Abstract
The term 'clustered regularly interspaced short palindromic repeats' (CRISPR) has recently become synonymous with the genome-editing revolution. The RNA-guided endonuclease CRISPR-associated protein 9 (Cas9), in particular, has attracted attention for its promise in basic research and gene editing-based therapeutics. CRISPR-Cas systems are efficient and easily programmable nucleic acid-targeting tools, with uses reaching beyond research and therapeutic development into the precision breeding of plants and animals and the engineering of industrial microbes. CRISPR-Cas systems have potential for many microbial engineering applications, including bacterial strain typing, immunization of cultures, autoimmunity or self-targeted cell killing, and the engineering or control of metabolic pathways for improved biochemical synthesis. In this review, we explore the fundamental characteristics of CRISPR-Cas systems and highlight how these features can be used in industrial settings.
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Affiliation(s)
- Paul D Donohoue
- Caribou Biosciences, Inc., 2929 7th St., Suite 105, Berkeley, CA 94710, USA
| | - Rodolphe Barrangou
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Andrew P May
- Caribou Biosciences, Inc., 2929 7th St., Suite 105, Berkeley, CA 94710, USA; Current address: Chan Zuckerberg Biohub, 499 Illinois St, San Francisco, CA 94158, USA.
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10
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Ferreira R, David F, Nielsen J. Advancing biotechnology with CRISPR/Cas9: recent applications and patent landscape. J Ind Microbiol Biotechnol 2018; 45:467-480. [PMID: 29362972 DOI: 10.1007/s10295-017-2000-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 12/19/2017] [Indexed: 12/24/2022]
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR) is poised to become one of the key scientific discoveries of the twenty-first century. Originating from prokaryotic and archaeal immune systems to counter phage invasions, CRISPR-based applications have been tailored for manipulating a broad range of living organisms. From the different elucidated types of CRISPR mechanisms, the type II system adapted from Streptococcus pyogenes has been the most exploited as a tool for genome engineering and gene regulation. In this review, we describe the different applications of CRISPR/Cas9 technology in the industrial biotechnology field. Next, we detail the current status of the patent landscape, highlighting its exploitation through different companies, and conclude with future perspectives of this technology.
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Affiliation(s)
- Raphael Ferreira
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Göteborg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 412 96, Göteborg, Sweden
| | - Florian David
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Göteborg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 412 96, Göteborg, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Göteborg, Sweden.
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 412 96, Göteborg, Sweden.
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.
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11
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Mohanta TK, Bashir T, Hashem A, Abd Allah EF, Bae H. Genome Editing Tools in Plants. Genes (Basel) 2017; 8:E399. [PMID: 29257124 PMCID: PMC5748717 DOI: 10.3390/genes8120399] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 12/08/2017] [Accepted: 12/15/2017] [Indexed: 12/23/2022] Open
Abstract
Genome editing tools have the potential to change the genomic architecture of a genome at precise locations, with desired accuracy. These tools have been efficiently used for trait discovery and for the generation of plants with high crop yields and resistance to biotic and abiotic stresses. Due to complex genomic architecture, it is challenging to edit all of the genes/genomes using a particular genome editing tool. Therefore, to overcome this challenging task, several genome editing tools have been developed to facilitate efficient genome editing. Some of the major genome editing tools used to edit plant genomes are: Homologous recombination (HR), zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), pentatricopeptide repeat proteins (PPRs), the CRISPR/Cas9 system, RNA interference (RNAi), cisgenesis, and intragenesis. In addition, site-directed sequence editing and oligonucleotide-directed mutagenesis have the potential to edit the genome at the single-nucleotide level. Recently, adenine base editors (ABEs) have been developed to mutate A-T base pairs to G-C base pairs. ABEs use deoxyadeninedeaminase (TadA) with catalytically impaired Cas9 nickase to mutate A-T base pairs to G-C base pairs.
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Affiliation(s)
| | - Tufail Bashir
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541, Korea.
| | - Abeer Hashem
- Botany and Microbiology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
- Mycology and Plant Disease Survey Department, Plant Pathology Research Institute, Agriculture Research Center, Giza 12619, Egypt.
| | - Elsayed Fathi Abd Allah
- Plant Production Department, College of Food and Agriculture Science, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Hanhong Bae
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541, Korea.
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12
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Arora L, Narula A. Gene Editing and Crop Improvement Using CRISPR-Cas9 System. FRONTIERS IN PLANT SCIENCE 2017; 8:1932. [PMID: 29167680 PMCID: PMC5682324 DOI: 10.3389/fpls.2017.01932] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/25/2017] [Indexed: 05/04/2023]
Abstract
Advancements in Genome editing technologies have revolutionized the fields of functional genomics and crop improvement. CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat)-Cas9 is a multipurpose technology for genetic engineering that relies on the complementarity of the guideRNA (gRNA) to a specific sequence and the Cas9 endonuclease activity. It has broadened the agricultural research area, bringing in new opportunities to develop novel plant varieties with deletion of detrimental traits or addition of significant characters. This RNA guided genome editing technology is turning out to be a groundbreaking innovation in distinct branches of plant biology. CRISPR technology is constantly advancing including options for various genetic manipulations like generating knockouts; making precise modifications, multiplex genome engineering, and activation and repression of target genes. The review highlights the progression throughout the CRISPR legacy. We have studied the rapid evolution of CRISPR/Cas9 tools with myriad functionalities, capabilities, and specialized applications. Among varied diligences, plant nutritional improvement, enhancement of plant disease resistance and production of drought tolerant plants are reviewed. The review also includes some information on traditional delivery methods of Cas9-gRNA complexes into plant cells and incorporates the advent of CRISPR ribonucleoproteins (RNPs) that came up as a solution to various limitations that prevailed with plasmid-based CRISPR system.
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Affiliation(s)
| | - Alka Narula
- Department of Biotechnology, School of Chemical and Life Sciences, Jamia Hamdard University, New Delhi, India
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Boyle M, Mann J. WITHDRAWN: Epigenetics in Chronic Liver Disease. J Hepatol 2017:S0168-8278(17)32255-9. [PMID: 28855099 DOI: 10.1016/j.jhep.2017.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 08/17/2017] [Accepted: 08/18/2017] [Indexed: 12/04/2022]
Abstract
This article has been withdrawn at the request of the editors. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
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Affiliation(s)
- Marie Boyle
- Institute of Cellular Medicine, Faculty of Medical Sciences, 4(th) Floor, William Leech Building, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Jelena Mann
- Institute of Cellular Medicine, Faculty of Medical Sciences, 4(th) Floor, William Leech Building, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
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Banerjee A, Banerjee C, Negi S, Chang JS, Shukla P. Improvements in algal lipid production: a systems biology and gene editing approach. Crit Rev Biotechnol 2017; 38:369-385. [DOI: 10.1080/07388551.2017.1356803] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Avik Banerjee
- Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, India
| | - Chiranjib Banerjee
- Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, India
| | | | - Jo-Shu Chang
- Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Pratyoosh Shukla
- Department of Microbiology, Enzyme Technology and Protein Bioinformatics Laboratory, Maharshi Dayanand University, Rohtak, India
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Czapiński J, Kiełbus M, Kałafut J, Kos M, Stepulak A, Rivero-Müller A. How to Train a Cell-Cutting-Edge Molecular Tools. Front Chem 2017; 5:12. [PMID: 28344971 PMCID: PMC5344921 DOI: 10.3389/fchem.2017.00012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 02/20/2017] [Indexed: 12/28/2022] Open
Abstract
In biological systems, the formation of molecular complexes is the currency for all cellular processes. Traditionally, functional experimentation was targeted to single molecular players in order to understand its effects in a cell or animal phenotype. In the last few years, we have been experiencing rapid progress in the development of ground-breaking molecular biology tools that affect the metabolic, structural, morphological, and (epi)genetic instructions of cells by chemical, optical (optogenetic) and mechanical inputs. Such precise dissection of cellular processes is not only essential for a better understanding of biological systems, but will also allow us to better diagnose and fix common dysfunctions. Here, we present several of these emerging and innovative techniques by providing the reader with elegant examples on how these tools have been implemented in cells, and, in some cases, organisms, to unravel molecular processes in minute detail. We also discuss their advantages and disadvantages with particular focus on their translation to multicellular organisms for in vivo spatiotemporal regulation. We envision that further developments of these tools will not only help solve the processes of life, but will give rise to novel clinical and industrial applications.
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Affiliation(s)
- Jakub Czapiński
- Department of Biochemistry and Molecular Biology, Medical University of LublinLublin, Poland
- Postgraduate School of Molecular Medicine, Medical University of WarsawWarsaw, Poland
| | - Michał Kiełbus
- Department of Biochemistry and Molecular Biology, Medical University of LublinLublin, Poland
| | - Joanna Kałafut
- Department of Biochemistry and Molecular Biology, Medical University of LublinLublin, Poland
| | - Michał Kos
- Department of Biochemistry and Molecular Biology, Medical University of LublinLublin, Poland
| | - Andrzej Stepulak
- Department of Biochemistry and Molecular Biology, Medical University of LublinLublin, Poland
| | - Adolfo Rivero-Müller
- Department of Biochemistry and Molecular Biology, Medical University of LublinLublin, Poland
- Turku Centre for Biotechnology, University of Turku and Åbo Akademi UniversityTurku, Finland
- Department of Biosciences, Åbo Akademi UniversityTurku, Finland
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Leenay RT, Beisel CL. Deciphering, Communicating, and Engineering the CRISPR PAM. J Mol Biol 2017; 429:177-191. [PMID: 27916599 PMCID: PMC5235977 DOI: 10.1016/j.jmb.2016.11.024] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/15/2016] [Accepted: 11/25/2016] [Indexed: 12/26/2022]
Abstract
Clustered regularly interspaced short palindromic repeat (CRISPR) loci and their flanking CRISPR-associated (cas) genes make up RNA-guided, adaptive immune systems in prokaryotes whose effector proteins have become powerful tools for basic research and biotechnology. While the Cas effector proteins are remarkably diverse, they commonly rely on protospacer-adjacent motifs (PAMs) as the first step in target recognition. PAM sequences are known to vary considerably between systems and have proven to be difficult to predict, spurring the need for new tools to rapidly identify and communicate these sequences. Recent advances have also shown that Cas proteins can be engineered to alter PAM recognition, opening new opportunities to develop CRISPR-based tools with enhanced targeting capabilities. In this review, we discuss the properties of the CRISPR PAM and the emerging tools for determining, visualizing, and engineering PAM recognition. We also propose a standard means of orienting the PAM to simplify how its location and sequence are communicated.
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Affiliation(s)
- Ryan T Leenay
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, United States
| | - Chase L Beisel
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, United States.
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Abstract
Prokaryotes use diverse strategies to improve fitness in the face of different environmental threats and stresses, including those posed by mobile genetic elements (e.g., bacteriophages and plasmids). To defend against these elements, many bacteria and archaea use elegant, RNA-directed, nucleic acid-targeting adaptive restriction machineries called CRISPR -: Cas (CRISPR-associated) systems. While providing an effective defense against foreign genetic elements, these systems have also been observed to play critical roles in regulating bacterial physiology during environmental stress. Increasingly, CRISPR-Cas systems, in particular the Type II systems containing the Cas9 endonuclease, have been exploited for their ability to bind desired nucleic acid sequences, as well as direct sequence-specific cleavage of their targets. Cas9-mediated genome engineering is transcending biological research as a versatile and portable platform for manipulating genetic content in myriad systems. Here, we present a systematic overview of CRISPR-Cas history and biology, highlighting the revolutionary tools derived from these systems, which greatly expand the molecular biologists' toolkit.
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Affiliation(s)
- Hannah K Ratner
- Department of Microbiology and Immunology, Microbiology and Molecular Genetics Program, Emory University, Atlanta, Georgia 30329
- Emory Vaccine Center, Emory University, Atlanta, Georgia 30329
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
| | - Timothy R Sampson
- Department of Microbiology and Immunology, Microbiology and Molecular Genetics Program, Emory University, Atlanta, Georgia 30329
- Emory Vaccine Center, Emory University, Atlanta, Georgia 30329
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
| | - David S Weiss
- Emory Vaccine Center, Emory University, Atlanta, Georgia 30329
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30329
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Savitskaya EE, Musharova OS, Severinov KV. Diversity of CRISPR-Cas-mediated mechanisms of adaptive immunity in prokaryotes and their application in biotechnology. BIOCHEMISTRY (MOSCOW) 2016; 81:653-61. [DOI: 10.1134/s0006297916070026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Hung SSC, McCaughey T, Swann O, Pébay A, Hewitt AW. Genome engineering in ophthalmology: Application of CRISPR/Cas to the treatment of eye disease. Prog Retin Eye Res 2016; 53:1-20. [PMID: 27181583 DOI: 10.1016/j.preteyeres.2016.05.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 04/30/2016] [Accepted: 05/04/2016] [Indexed: 12/12/2022]
Abstract
The Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) and CRISPR-associated protein (Cas) system has enabled an accurate and efficient means to edit the human genome. Rapid advances in this technology could results in imminent clinical application, and with favourable anatomical and immunological profiles, ophthalmic disease will be at the forefront of such work. There have been a number of breakthroughs improving the specificity and efficacy of CRISPR/Cas-mediated genome editing. Similarly, better methods to identify off-target cleavage sites have also been developed. With the impending clinical utility of CRISPR/Cas technology, complex ethical issues related to the regulation and management of the precise applications of human gene editing must be considered. This review discusses the current progress and recent breakthroughs in CRISPR/Cas-based gene engineering, and outlines some of the technical issues that must be addressed before gene correction, be it in vivo or in vitro, is integrated into ophthalmic care. We outline a clinical pipeline for CRISPR-based treatments of inherited eye diseases and provide an overview of the important ethical implications of gene editing and how these may influence the future of this technology.
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Affiliation(s)
- Sandy S C Hung
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Tristan McCaughey
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Department of Surgery, Monash University, Victoria, Australia
| | - Olivia Swann
- Menzies Institute for Medical Research, School of Medicine, University of Tasmania, Australia
| | - Alice Pébay
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Alex W Hewitt
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Menzies Institute for Medical Research, School of Medicine, University of Tasmania, Australia.
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20
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Piatek A, Mahfouz MM. Targeted genome regulation via synthetic programmable transcriptional regulators. Crit Rev Biotechnol 2016; 37:429-440. [DOI: 10.3109/07388551.2016.1165180] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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21
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Low A, Shen Z, Cheng D, Rogers MJ, Lee PKH, He J. A comparative genomics and reductive dehalogenase gene transcription study of two chloroethene-respiring bacteria, Dehalococcoides mccartyi strains MB and 11a. Sci Rep 2015; 5:15204. [PMID: 26541266 PMCID: PMC4635342 DOI: 10.1038/srep15204] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 09/21/2015] [Indexed: 01/02/2023] Open
Abstract
Genomes of two trichloroethene (TCE)-respiring Dehalococcoides (Dhc) mccartyi, strains MB and 11a, were sequenced to identify reductive dehalogenases (RDase) responsible for oraganohalide respiration. Transcription analyses were conducted to verify the roles of RDase subunit A genes (rdhA) in chloroethene respiration. Some interesting features of the strain MB draft genome include a large genome size, two CRISPR-cas type I systems, and 38 rdhA genes. Strain 11a has a stream-lined genome with 11 rdhA genes, of which nine are distinct. Quantitative real-time PCR transcription analysis of RDase gene transcripts showed that a single RDase gene, designated mbrA, was up-regulated upon exposure to TCE and no other RDase genes were considerably expressed in strain MB. A single RDase gene, designated vcrA, was up-regulated upon exposure to TCE and expressed at a steady level until all chloroethenes were completely dechlorinated to ethene at 147 h in strain 11a. Overall, this study reports the genomes of two distinct Dhc strains; both contain numerous uncharacterized RDase genes, but in each strain only one such gene was expressed highly during organohalide respiration.
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Affiliation(s)
- Adrian Low
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
| | - Zhiyong Shen
- B5423-AC1, School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Dan Cheng
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
| | - Matthew J Rogers
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
| | - Patrick K H Lee
- B5423-AC1, School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
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22
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Kumar MS, Plotkin JB, Hannenhalli S. Regulated CRISPR Modules Exploit a Dual Defense Strategy of Restriction and Abortive Infection in a Model of Prokaryote-Phage Coevolution. PLoS Comput Biol 2015; 11:e1004603. [PMID: 26544847 PMCID: PMC4636164 DOI: 10.1371/journal.pcbi.1004603] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 10/14/2015] [Indexed: 11/23/2022] Open
Abstract
CRISPRs offer adaptive immunity in prokaryotes by acquiring genomic fragments from infecting phage and subsequently exploiting them for phage restriction via an RNAi-like mechanism. Here, we develop and analyze a dynamical model of CRISPR-mediated prokaryote-phage coevolution that incorporates classical CRISPR kinetics along with the recently discovered infection-induced activation and autoimmunity side effects. Our analyses reveal two striking characteristics of the CRISPR defense strategy: that both restriction and abortive infections operate during coevolution with phages, driving phages to much lower densities than possible with restriction alone, and that CRISPR maintenance is determined by a key dimensionless combination of parameters, which upper bounds the activation level of CRISPRs in uninfected populations. We contrast these qualitative observations with experimental data on CRISPR kinetics, which offer insight into the spacer deletion mechanism and the observed low CRISPR prevalence in clinical isolates. More generally, we exploit numerical simulations to delineate four regimes of CRISPR dynamics in terms of its host, kinetic, and regulatory parameters. To counteract viral infections, bacteria and archaea have evolved a variety of defense systems. These can broadly be classified into either restriction or suicide mechanisms. The former enforces nicks in the invading DNA making it unusable for production of further infectious particles; the latter, by contrast, induces cell death whereby an infected cell activates specific host suicidal pathways that are otherwise strongly repressed, thus inhibiting further infection. Examples of the former class include restriction-modification (R-M) and the recently discovered CRISPR systems, while the latter class includes a variety of toxin/anti-toxin systems. CRISPRs, in contrast to R-Ms, adapt to target viral genomes by updating the database of target sites they recognize. The adverse side effect of such a mechanism, however, is that CRISPRs can target the host genome itself resulting in undesirable cell death (autoimmunity). The recent discovery of infection-induced activation of CRISPR systems suggests that these negative side effects may be limited to periods of infection. This led us to hypothesize that such regulatory control—similar to abortive infection mechanisms—can be advantageous by limiting viral spread through suicide of infected cells. To test this hypothesis, we mathematically model CRISPR induced prokaryote-phage coevolutionary dynamics in the presence of infection-regulated CRISPR activity. Our results indicate that, except in limited growth rates, regulated CRISPRs exploit both autoimmunity and target restriction and can therefore be considered a hybrid class that leverages both restriction and suicide mechanisms to limit phage infection.
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Affiliation(s)
- M. Senthil Kumar
- Graduate Program in Bioinformatics, University of Maryland, College Park, Maryland, United States of America
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
- * E-mail: (MSK); (JBP); (SH)
| | - Joshua B. Plotkin
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail: (MSK); (JBP); (SH)
| | - Sridhar Hannenhalli
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
- * E-mail: (MSK); (JBP); (SH)
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Luo ML, Leenay RT, Beisel CL. Current and future prospects for CRISPR-based tools in bacteria. Biotechnol Bioeng 2015; 113:930-43. [PMID: 26460902 DOI: 10.1002/bit.25851] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 09/04/2015] [Accepted: 10/05/2015] [Indexed: 12/26/2022]
Abstract
CRISPR-Cas systems have rapidly transitioned from intriguing prokaryotic defense systems to powerful and versatile biomolecular tools. This article reviews how these systems have been translated into technologies to manipulate bacterial genetics, physiology, and communities. Recent applications in bacteria have centered on multiplexed genome editing, programmable gene regulation, and sequence-specific antimicrobials, while future applications can build on advances in eukaryotes, the rich natural diversity of CRISPR-Cas systems, and the untapped potential of CRISPR-based DNA acquisition. Overall, these systems have formed the basis of an ever-expanding genetic toolbox and hold tremendous potential for our future understanding and engineering of the bacterial world.
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Affiliation(s)
- Michelle L Luo
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, 27695-7905
| | - Ryan T Leenay
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, 27695-7905
| | - Chase L Beisel
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, 27695-7905.
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Nicholson SA, Moyo B, Arbuthnot PB. Progress and prospects of engineered sequence-specific DNA modulating technologies for the management of liver diseases. World J Hepatol 2015; 7:859-873. [PMID: 25937863 PMCID: PMC4411528 DOI: 10.4254/wjh.v7.i6.859] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/16/2014] [Accepted: 01/20/2015] [Indexed: 02/06/2023] Open
Abstract
Liver diseases are one of the leading causes of mortality in the world. The hepatic illnesses, which include inherited metabolic disorders, hemophilias and viral hepatitides, are complex and currently difficult to treat. The maturation of gene therapy has heralded new avenues for developing effective intervention for these diseases. DNA modification using gene therapy is now possible and available technology may be exploited to achieve long term therapeutic benefit. The ability to edit DNA sequences specifically is of paramount importance to advance gene therapy for application to liver diseases. Recent development of technologies that allow for this has resulted in rapid advancement of gene therapy to treat several chronic illnesses. Improvements in application of derivatives of zinc finger proteins (ZFPs), transcription activator-like effectors (TALEs), homing endonucleases (HEs) and clustered regularly interspaced palindromic repeats (CRISPR) and CRISPR associated (Cas) systems have been particularly important. These sequence-specific technologies may be used to modify genes permanently and also to alter gene transcription for therapeutic purposes. This review describes progress in development of ZFPs, TALEs, HEs and CRISPR/Cas for application to treating liver diseases.
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Mikalsen T, Pedersen T, Willems R, Coque TM, Werner G, Sadowy E, van Schaik W, Jensen LB, Sundsfjord A, Hegstad K. Investigating the mobilome in clinically important lineages of Enterococcus faecium and Enterococcus faecalis. BMC Genomics 2015; 16:282. [PMID: 25885771 PMCID: PMC4438569 DOI: 10.1186/s12864-015-1407-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 02/27/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The success of Enterococcus faecium and E. faecalis evolving as multi-resistant nosocomial pathogens is associated with their ability to acquire and share adaptive traits, including antimicrobial resistance genes encoded by mobile genetic elements (MGEs). Here, we investigate this mobilome in successful hospital associated genetic lineages, E. faecium sequence type (ST)17 (n=10) and ST78 (n=10), E. faecalis ST6 (n=10) and ST40 (n=10) by DNA microarray analyses. RESULTS The hybridization patterns of 272 representative targets including plasmid backbones (n=85), transposable elements (n=85), resistance determinants (n=67), prophages (n=29) and clustered regularly interspaced short palindromic repeats (CRISPR)-cas sequences (n=6) separated the strains according to species, and for E. faecalis also according to STs. RCR-, Rep_3-, RepA_N- and Inc18-family plasmids were highly prevalent and with the exception of Rep_3, evenly distributed between the species. There was a considerable difference in the replicon profile, with rep 17/pRUM , rep 2/pRE25 , rep 14/EFNP1 and rep 20/pLG1 dominating in E. faecium and rep 9/pCF10 , rep 2/pRE25 and rep 7 in E. faecalis strains. We observed an overall high correlation between the presence and absence of genes coding for resistance towards antibiotics, metals, biocides and their corresponding MGEs as well as their phenotypic antimicrobial susceptibility pattern. Although most IS families were represented in both E. faecalis and E. faecium, specific IS elements within these families were distributed in only one species. The prevalence of IS256-, IS3-, ISL3-, IS200/IS605-, IS110-, IS982- and IS4-transposases was significantly higher in E. faecium than E. faecalis, and that of IS110-, IS982- and IS1182-transposases in E. faecalis ST6 compared to ST40. Notably, the transposases of IS981, ISEfm1 and IS1678 that have only been reported in few enterococcal isolates were well represented in the E. faecium strains. E. faecalis ST40 strains harboured possible functional CRISPR-Cas systems, and still resistance and prophage sequences were generally well represented. CONCLUSIONS The targeted MGEs were highly prevalent among the selected STs, underlining their potential importance in the evolution of hospital-adapted lineages of enterococci. Although the propensity of inter-species horizontal gene transfer (HGT) must be emphasized, the considerable species-specificity of these MGEs indicates a separate vertical evolution of MGEs within each species, and for E. faecalis within each ST.
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Affiliation(s)
- Theresa Mikalsen
- Research group for Host-microbe Interactions, Department of Medical Biology, Faculty of Health Science, UiT - The Arctic University of Norway, Tromsø, Norway.
| | - Torunn Pedersen
- Norwegian National Advisory Unit on Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway.
| | - Rob Willems
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - Teresa M Coque
- Servicio de Microbiologia, Hospital Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain. .,Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBER-ESP), Madrid, Spain.
| | - Guido Werner
- Division of Nosocomial Pathogens and Antibiotic Resistance, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany.
| | - Ewa Sadowy
- Department of Molecular Microbiology, National Medicines Institute, ul, Chełmska 30/34, 00-725, Warsaw, Poland.
| | - Willem van Schaik
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - Lars Bogø Jensen
- Division of Food Microbiologyt, National Food Institute, Danish Technical University, Copenhagen V, Denmark.
| | - Arnfinn Sundsfjord
- Research group for Host-microbe Interactions, Department of Medical Biology, Faculty of Health Science, UiT - The Arctic University of Norway, Tromsø, Norway. .,Norwegian National Advisory Unit on Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway.
| | - Kristin Hegstad
- Research group for Host-microbe Interactions, Department of Medical Biology, Faculty of Health Science, UiT - The Arctic University of Norway, Tromsø, Norway. .,Norwegian National Advisory Unit on Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway.
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Abstract
ABSTRACT
The number and diversity of known prokaryotic insertion sequences (IS) have increased enormously since their discovery in the late 1960s. At present the sequences of more than 4000 different IS have been deposited in the specialized ISfinder database. Over time it has become increasingly apparent that they are important actors in the evolution of their host genomes and are involved in sequestering, transmitting, mutating and activating genes, and in the rearrangement of both plasmids and chromosomes. This review presents an overview of our current understanding of these transposable elements (TE), their organization and their transposition mechanism as well as their distribution and genomic impact. In spite of their diversity, they share only a very limited number of transposition mechanisms which we outline here. Prokaryotic IS are but one example of a variety of diverse TE which are being revealed due to the advent of extensive genome sequencing projects. A major conclusion from sequence comparisons of various TE is that frontiers between the different types are becoming less clear. We detail these receding frontiers between different IS-related TE. Several, more specialized chapters in this volume include additional detailed information concerning a number of these.
In a second section of the review, we provide a detailed description of the expanding variety of IS, which we have divided into families for convenience. Our perception of these families continues to evolve and families emerge regularly as more IS are identified. This section is designed as an aid and a source of information for consultation by interested specialist readers.
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devI is an evolutionarily young negative regulator of Myxococcus xanthus development. J Bacteriol 2015; 197:1249-62. [PMID: 25645563 DOI: 10.1128/jb.02542-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED During starvation-induced development of Myxococcus xanthus, thousands of rod-shaped cells form mounds in which they differentiate into spores. The dev locus includes eight genes followed by clustered regularly interspaced short palindromic repeats (CRISPRs), comprising a CRISPR-Cas system (Cas stands for CRISPR associated) typically involved in RNA interference. Mutations in devS or devR of a lab reference strain permit mound formation but impair sporulation. We report that natural isolates of M. xanthus capable of normal development are highly polymorphic in the promoter region of the dev operon. We show that the dev promoter is predicted to be nonfunctional in most natural isolates and is dispensable for development of a laboratory reference strain. Moreover, deletion of the dev promoter or the small gene immediately downstream of it, here designated devI (development inhibitor), suppressed the sporulation defect of devS or devR mutants in the lab strain. Complementation experiments and the result of introducing a premature stop codon in devI support a model in which DevRS proteins negatively autoregulate expression of devI, whose 40-residue protein product DevI inhibits sporulation if overexpressed. DevI appears to act in a cell-autonomous manner since experiments with conditioned medium and with cell mixtures gave no indication of extracellular effects. Strikingly, we report that devI is entirely absent from most M. xanthus natural isolates and was only recently integrated into the developmental programs of some lineages. These results provide important new insights into both the evolutionary history of the dev operon and its mechanistic role in M. xanthus sporulation. IMPORTANCE Certain mutations in the dev CRISPR-Cas (clustered regularly interspaced short palindromic repeat-associated) system of Myxococcus xanthus impair sporulation. The link between development and a CRISPR-Cas system has been a mystery. Surprisingly, DNA sequencing of natural isolates revealed that many appear to lack a functional dev promoter, yet these strains sporulate normally. Deletion of the dev promoter or the small gene downstream of it suppressed the sporulation defect of a lab strain with mutations in dev genes encoding Cas proteins. The results support a model in which the Cas proteins DevRS prevent overexpression of the small gene devI, which codes for an inhibitor of sporulation. Phylogenetic analysis of natural isolates suggests that devI and the dev promoter were only recently acquired in some lineages.
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Yang IV, Schwartz DA. Epigenetics of idiopathic pulmonary fibrosis. Transl Res 2015; 165:48-60. [PMID: 24746870 PMCID: PMC4182166 DOI: 10.1016/j.trsl.2014.03.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 03/18/2014] [Accepted: 03/21/2014] [Indexed: 12/15/2022]
Abstract
Idiopathic pulmonary fibrosis (IPF) is a complex lung disease of unknown etiology. Development of IPF is influenced by both genetic and environmental factors. Recent work by our and other groups has identified strong genetic predisposition factors for the development of pulmonary fibrosis, and cigarette smoke remains the most strongly associated environmental exposure risk factor. Gene expression profiling studies of IPF lung have taught us quite a bit about the biology of this fatal disease, and those of peripheral blood have provided important biomarkers. However, epigenetic marks may be the missing link that connects the environmental exposure in genetically predisposed individuals to transcriptional changes associated with disease development. Moreover, epigenetic marks represent a promising therapeutic target for IPF. In this review, the disease is introduced, genetic and gene expression studies in IPF are summarized, exposures relevant to IPF and known epigenetic changes associated with cigarette smoke exposure are discussed, and epigenetic studies conducted so far in IPF are summarized. Limitations, challenges, and future opportunities in this field are also discussed.
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Affiliation(s)
- Ivana V Yang
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colo; Department of Epidemiology, Colorado School of Public Health, Aurora, Colo.
| | - David A Schwartz
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colo; Department of Immunology, University of Colorado School of Medicine, Aurora, Colo
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Maier LK, Stachler AE, Saunders SJ, Backofen R, Marchfelder A. An active immune defense with a minimal CRISPR (clustered regularly interspaced short palindromic repeats) RNA and without the Cas6 protein. J Biol Chem 2014; 290:4192-201. [PMID: 25512373 PMCID: PMC4326828 DOI: 10.1074/jbc.m114.617506] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The prokaryotic immune system CRISPR-Cas (clustered regularly interspaced short palindromic repeats-CRISPR-associated) is a defense system that protects prokaryotes against foreign DNA. The short CRISPR RNAs (crRNAs) are central components of this immune system. In CRISPR-Cas systems type I and III, crRNAs are generated by the endonuclease Cas6. We developed a Cas6b-independent crRNA maturation pathway for the Haloferax type I-B system in vivo that expresses a functional crRNA, which we termed independently generated crRNA (icrRNA). The icrRNA is effective in triggering degradation of an invader plasmid carrying the matching protospacer sequence. The Cas6b-independent maturation of the icrRNA allowed mutation of the repeat sequence without interfering with signals important for Cas6b processing. We generated 23 variants of the icrRNA and analyzed them for activity in the interference reaction. icrRNAs with deletions or mutations of the 3′ handle are still active in triggering an interference reaction. The complete 3′ handle could be removed without loss of activity. However, manipulations of the 5′ handle mostly led to loss of interference activity. Furthermore, we could show that in the presence of an icrRNA a strain without Cas6b (Δcas6b) is still active in interference.
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Affiliation(s)
| | | | - Sita J Saunders
- the Bioinformatics Group, Department of Computer Science, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 106, 79110 Freiburg, and
| | - Rolf Backofen
- the Bioinformatics Group, Department of Computer Science, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 106, 79110 Freiburg, and the BIOSS Centre for Biological Signalling Studies, Cluster of Excellence, Albert-Ludwigs-University Freiburg, Schänzlestrasse 18, 79104 Freiburg, Germany
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Abstract
The use of transgenics in fish is a relatively recent development for advancing understanding of genetic mechanisms and developmental processes, improving aquaculture, and for pharmaceutical discovery. Transgenic fish have also been applied in ecotoxicology where they have the potential to provide more advanced and integrated systems for assessing health impacts of chemicals. The zebrafish (Daniorerio) is the most popular fish for transgenic models, for reasons including their high fecundity, transparency of their embryos, rapid organogenesis and availability of extensive genetic resources. The most commonly used technique for producing transgenic zebrafish is via microinjection of transgenes into fertilized eggs. Transposon and meganuclease have become the most reliable methods for insertion of the genetic construct in the production of stable transgenic fish lines. The GAL4-UAS system, where GAL4 is placed under the control of a desired promoter and UAS is fused with a fluorescent marker, has greatly enhanced model development for studies in ecotoxicology. Transgenic fish have been developed to study for the effects of heavy metal toxicity (via heat-shock protein genes), oxidative stress (via an electrophile-responsive element), for various organic chemicals acting through the aryl hydrocarbon receptor, thyroid and glucocorticoid response pathways, and estrogenicity. These models vary in their sensitivity with only very few able to detect responses for environmentally relevant exposures. Nevertheless, the potential of these systems for analyses of chemical effects in real time and across multiple targets in intact organisms is considerable. Here we illustrate the techniques used for generating transgenic zebrafish and assess progress in the development and application of transgenic fish (principally zebrafish) for studies in environmental toxicology. We further provide a viewpoint on future development opportunities.
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Affiliation(s)
- Okhyun Lee
- Biosciences, College of Life & Environmental Sciences, University of Exeter , Exeter, Devon , UK
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Luo ML, Mullis AS, Leenay RT, Beisel CL. Repurposing endogenous type I CRISPR-Cas systems for programmable gene repression. Nucleic Acids Res 2014. [PMID: 25326321 DOI: 10.1093/nar/gku971.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
CRISPR-Cas systems have shown tremendous promise as heterologous tools for genome editing and transcriptional regulation. Because these RNA-directed immune systems are found in most prokaryotes, an opportunity exists to harness the endogenous systems as convenient tools in these organisms. Here, we report that the Type I-E CRISPR-Cas system in Escherichia coli can be co-opted for programmable transcriptional repression. We found that deletion of the signature cas3 gene converted this immune system into a programmable gene regulator capable of reversible gene silencing of heterologous and endogenous genes. Targeting promoter regions yielded the strongest repression, whereas targeting coding regions showed consistent strand bias. Furthermore, multi-targeting CRISPR arrays could generate complex phenotypes. This strategy offers a simple approach to convert many endogenous Type I systems into transcriptional regulators, thereby expanding the available toolkit for CRISPR-mediated genetic control while creating new opportunities for genome-wide screens and pathway engineering.
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Affiliation(s)
- Michelle L Luo
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Adam S Mullis
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Ryan T Leenay
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Chase L Beisel
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
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Luo ML, Mullis AS, Leenay RT, Beisel CL. Repurposing endogenous type I CRISPR-Cas systems for programmable gene repression. Nucleic Acids Res 2014; 43:674-81. [PMID: 25326321 PMCID: PMC4288209 DOI: 10.1093/nar/gku971] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
CRISPR-Cas systems have shown tremendous promise as heterologous tools for genome editing and transcriptional regulation. Because these RNA-directed immune systems are found in most prokaryotes, an opportunity exists to harness the endogenous systems as convenient tools in these organisms. Here, we report that the Type I-E CRISPR-Cas system in Escherichia coli can be co-opted for programmable transcriptional repression. We found that deletion of the signature cas3 gene converted this immune system into a programmable gene regulator capable of reversible gene silencing of heterologous and endogenous genes. Targeting promoter regions yielded the strongest repression, whereas targeting coding regions showed consistent strand bias. Furthermore, multi-targeting CRISPR arrays could generate complex phenotypes. This strategy offers a simple approach to convert many endogenous Type I systems into transcriptional regulators, thereby expanding the available toolkit for CRISPR-mediated genetic control while creating new opportunities for genome-wide screens and pathway engineering.
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Affiliation(s)
- Michelle L Luo
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Adam S Mullis
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Ryan T Leenay
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Chase L Beisel
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
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Xie S, Shen B, Zhang C, Huang X, Zhang Y. sgRNAcas9: a software package for designing CRISPR sgRNA and evaluating potential off-target cleavage sites. PLoS One 2014; 9:e100448. [PMID: 24956386 PMCID: PMC4067335 DOI: 10.1371/journal.pone.0100448] [Citation(s) in RCA: 272] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 05/23/2014] [Indexed: 12/26/2022] Open
Abstract
Although the CRISPR/Cas9/sgRNA system efficiently cleaves intracellular DNA at desired target sites, major concerns remain on potential "off-target" cleavage that may occur throughout the whole genome. In order to improve CRISPR-Cas9 specificity for targeted genome editing and transcriptional control, we describe a bioinformatics tool "sgRNAcas9", which is a software package developed for fast design of CRISPR sgRNA with minimized off-target effects. This package consists of programs to perform a search for CRISPR target sites (protospacers) with user-defined parameters, predict genome-wide Cas9 potential off-target cleavage sites (POT), classify the POT into three categories, batch-design oligonucleotides for constructing 20-nt (nucleotides) or truncated sgRNA expression vectors, extract desired length nucleotide sequences flanking the on- or off-target cleavage sites for designing PCR primer pairs to validate the mutations by T7E1 cleavage assay. Importantly, by identifying potential off-target sites in silico, the sgRNAcas9 allows the selection of more specific target sites and aids the identification of bona fide off-target sites, significantly facilitating the design of sgRNA for genome editing applications. sgRNAcas9 software package is publicly available at BiooTools website (www.biootools.com) under the terms of the GNU General Public License.
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Affiliation(s)
- Shengsong Xie
- Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Bin Shen
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center of Nanjing University, Nanjing, China
| | - Chaobao Zhang
- Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xingxu Huang
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center of Nanjing University, Nanjing, China
| | - Yonglian Zhang
- Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- Shanghai Institute of Planned Parenthood Research, Shanghai, China
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Shapiro JA. Epigenetic control of mobile DNA as an interface between experience and genome change. Front Genet 2014; 5:87. [PMID: 24795749 PMCID: PMC4007016 DOI: 10.3389/fgene.2014.00087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 04/01/2014] [Indexed: 12/29/2022] Open
Abstract
Mobile DNA in the genome is subject to RNA-targeted epigenetic control. This control regulates the activity of transposons, retrotransposons and genomic proviruses. Many different life history experiences alter the activities of mobile DNA and the expression of genetic loci regulated by nearby insertions. The same experiences induce alterations in epigenetic formatting and lead to trans-generational modifications of genome expression and stability. These observations lead to the hypothesis that epigenetic formatting directed by non-coding RNA provides a molecular interface between life history events and genome alteration.
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Affiliation(s)
- James A. Shapiro
- Department of Biochemistry and Molecular Biology, University of ChicagoChicago, IL, USA
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