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2.
Nat Commun ; 11(1): 4906, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999292

RESUMO

The CRISPR-Cas12a RNA-guided complexes have tremendous potential for nucleic acid detection but are limited to the picomolar detection limit without an amplification step. Here, we develop a platform with engineered crRNAs and optimized conditions that enabled us to detect various clinically relevant nucleic acid targets with higher sensitivity, achieving a limit of detection in the femtomolar range without any target pre-amplification step. By extending the 3'- or 5'-ends of the crRNA with different lengths of ssDNA, ssRNA, and phosphorothioate ssDNA, we discover a self-catalytic behavior and an augmented rate of LbCas12a-mediated collateral cleavage activity as high as 3.5-fold compared to the wild-type crRNA and with significant improvement in specificity for target recognition. Particularly, the 7-mer DNA extension to crRNA is determined to be universal and spacer-independent for enhancing the sensitivity and specificity of LbCas12a-mediated nucleic acid detection. We perform a detailed characterization of our engineered ENHANCE system with various crRNA modifications, target types, reporters, and divalent cations. With isothermal amplification of SARS-CoV-2 RNA using RT-LAMP, the modified crRNAs are incorporated in a paper-based lateral flow assay that can detect the target with up to 23-fold higher sensitivity within 40-60 min.


Assuntos
Proteínas de Bactérias/metabolismo , Betacoronavirus/genética , Proteínas Associadas a CRISPR/metabolismo , Endodesoxirribonucleases/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/isolamento & purificação , Transativadores/metabolismo , Betacoronavirus/isolamento & purificação , Sistemas CRISPR-Cas , Técnicas de Laboratório Clínico , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , DNA de Cadeia Simples , Pandemias , Pneumonia Viral , RNA Guia/genética , RNA Viral/genética
3.
Curr Protoc Plant Biol ; 5(3): e20117, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32865887

RESUMO

CRISPR/Cas systems enable gene editing through the induction of site-specific DNA double-strand breaks (DSB). However, the nature of the induced modification highly depends on the mechanism used for DNA DSB repair. Non-homologous end joining (NHEJ)-mediated targeted mutagenesis induced by CRISPR/Cas is an already standardly applied tool, which can lead to various different kinds of mutations at a specific genomic site. Nevertheless, precise genome modification using homologous donor sequences is still challenging in plants. Applications depending on the less frequent homologous recombination (HR) require further improvements to create an attractive and efficient tool for general application in plants. Focusing on this issue, we developed the in planta gene targeting (ipGT) system, which is based on the simultaneous excision of a stably integrated, homologous donor sequence and the induction of a DSB within the target site. In recent years, several improvements were achieved enhancing gene targeting (GT) frequencies. After the successful application of Streptococcus pyogenes Cas9 (SpCas9) and Staphylococcus aureus Cas9 (SaCas9) for ipGT, we were able to further improve the system using Lachnospiraceae bacterium Cas12a (LbCas12a), which also enables cleavage in T-rich regions. Most recently, we tested an improved, temperature-tolerant version of LbCas12a (ttLbCas12a) for ipGT and were able to further increase GT efficiencies. Here, we describe the experimental procedure of the recently published ipGT system using ttLbCas12a in Arabidopsis thaliana in detail. © 2020 The Authors. Basic Protocol 1: Construction of CRISPR/ttLbCas12a expression vector to analyze ipGT efficiencies Basic Protocol 2: Achieving heritable GT plants.


Assuntos
Arabidopsis/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Sistemas CRISPR-Cas , Edição de Genes , Marcação de Genes
4.
Mol Cell ; 79(5): 703-704, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32888434

RESUMO

Jin et al. (2020) engineered new variants of CRISPR base editors that make precise genomic edits in rice protoplasts while minimizing untargeted mutagenesis.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes , Sistemas CRISPR-Cas , Citosina , DNA de Cadeia Simples , Desaminação
5.
Mol Cell ; 79(5): 705-707, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32888435

RESUMO

In this issue of Molecular Cell, Benslimane et al. (2020) perform a CRISPR-Cas9 chemogenomic screen, identifying a network of DNA replication and genome integrity genes with the nutraceutical compound Resveratrol and its analog Pterostilbene, linking these compounds to the induction of DNA replication stress in mammalian cells.


Assuntos
Replicação do DNA , Resveratrol , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Humanos
6.
PLoS Negl Trop Dis ; 14(8): e0008627, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866158

RESUMO

The application of reverse genetics in the human filarial parasites has lagged due to the difficult biology of these organisms. Recently, we developed a co-culture system that permitted the infective larval stage of Brugia malayi to be transfected and efficiently develop to fecund adults. This was exploited to develop a piggyBac transposon-based toolkit that can be used to produce parasites with transgene sequences stably integrated into the parasite genome. However, the piggyBac system has generally been supplanted by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) based technology, which allows precise editing of a genome. Here we report adapting the piggyBac mediated transfection system of B. malayi for CRISPR mediated knock-in insertion into the parasite genome. Suitable CRISPR insertion sites were identified in intergenic regions of the B. malayi genome. A dual reporter piggybac vector was modified, replacing the piggyBac inverted terminal repeat regions with sequences flanking the insertion site. B. malayi molting L3 were transfected with a synthetic guide RNA, the modified plasmid and the CAS9 nuclease. The transfected parasites were implanted into gerbils and allowed to develop into adults. Progeny microfilariae were recovered and screened for expression of a secreted luciferase reporter encoded in the plasmid. Approximately 3% of the microfilariae were found to secrete luciferase; all contained the transgenic sequences inserted at the expected location in the parasite genome. Using an adaptor mediated PCR assay, transgenic microfilariae were examined for the presence of off target insertions; no off-target insertions were found. These data demonstrate that CRISPR can be used to modify the genome of B. malayi, opening the way to precisely edit the genome of this important human filarial parasite.


Assuntos
Brugia Malayi/genética , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Transfecção/métodos , Animais , Animais Geneticamente Modificados , Sequência de Bases , DNA de Helmintos/genética , Feminino , Edição de Genes , Genoma , Larva/genética , Luciferases , Microfilárias/genética
7.
Sci Immunol ; 5(51)2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887845

RESUMO

A novel role for SWI/SNF complexes in tuning Foxp3 expression and activity in Tregs.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Nucleossomos , Proteínas Nucleares/genética , Linfócitos T Reguladores , Fatores de Transcrição/genética
8.
Mol Cell ; 79(5): 708-709, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32888436

RESUMO

The collaborative work of two HHMI groups, one at the University of Washington and the other at the Broad Institute of MIT and Harvard, led to the development of a novel molecular tool to edit single bases in the mtDNA (Mok et al., 2020).


Assuntos
Citidina Desaminase , DNA Mitocondrial , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Mitocôndrias/genética
9.
Pharmacol Rev ; 72(4): 862-898, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32929000

RESUMO

RNA-based therapies, including RNA molecules as drugs and RNA-targeted small molecules, offer unique opportunities to expand the range of therapeutic targets. Various forms of RNAs may be used to selectively act on proteins, transcripts, and genes that cannot be targeted by conventional small molecules or proteins. Although development of RNA drugs faces unparalleled challenges, many strategies have been developed to improve RNA metabolic stability and intracellular delivery. A number of RNA drugs have been approved for medical use, including aptamers (e.g., pegaptanib) that mechanistically act on protein target and small interfering RNAs (e.g., patisiran and givosiran) and antisense oligonucleotides (e.g., inotersen and golodirsen) that directly interfere with RNA targets. Furthermore, guide RNAs are essential components of novel gene editing modalities, and mRNA therapeutics are under development for protein replacement therapy or vaccination, including those against unprecedented severe acute respiratory syndrome coronavirus pandemic. Moreover, functional RNAs or RNA motifs are highly structured to form binding pockets or clefts that are accessible by small molecules. Many natural, semisynthetic, or synthetic antibiotics (e.g., aminoglycosides, tetracyclines, macrolides, oxazolidinones, and phenicols) can directly bind to ribosomal RNAs to achieve the inhibition of bacterial infections. Therefore, there is growing interest in developing RNA-targeted small-molecule drugs amenable to oral administration, and some (e.g., risdiplam and branaplam) have entered clinical trials. Here, we review the pharmacology of novel RNA drugs and RNA-targeted small-molecule medications, with a focus on recent progresses and strategies. Challenges in the development of novel druggable RNA entities and identification of viable RNA targets and selective small-molecule binders are discussed. SIGNIFICANCE STATEMENT: With the understanding of RNA functions and critical roles in diseases, as well as the development of RNA-related technologies, there is growing interest in developing novel RNA-based therapeutics. This comprehensive review presents pharmacology of both RNA drugs and RNA-targeted small-molecule medications, focusing on novel mechanisms of action, the most recent progress, and existing challenges.


Assuntos
RNA/efeitos dos fármacos , RNA/farmacologia , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/uso terapêutico , Betacoronavirus , Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/normas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Infecções por Coronavirus/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Desenvolvimento de Medicamentos/organização & administração , Descoberta de Drogas , Humanos , MicroRNAs/farmacologia , MicroRNAs/uso terapêutico , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , Pandemias , Pneumonia Viral/tratamento farmacológico , RNA/efeitos adversos , RNA Antissenso/farmacologia , RNA Antissenso/uso terapêutico , RNA Guia/farmacologia , RNA Guia/uso terapêutico , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/farmacologia , RNA Ribossômico/efeitos dos fármacos , RNA Ribossômico/farmacologia , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/uso terapêutico , RNA Viral/efeitos dos fármacos , Ribonucleases/metabolismo , Riboswitch/efeitos dos fármacos
10.
Nat Commun ; 11(1): 4813, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968076

RESUMO

Artemisinins have revolutionized the treatment of Plasmodium falciparum malaria; however, resistance threatens to undermine global control efforts. To broadly explore artemisinin susceptibility in apicomplexan parasites, we employ genome-scale CRISPR screens recently developed for Toxoplasma gondii to discover sensitizing and desensitizing mutations. Using a sublethal concentration of dihydroartemisinin (DHA), we uncover the putative transporter Tmem14c whose disruption increases DHA susceptibility. Screens performed under high doses of DHA provide evidence that mitochondrial metabolism can modulate resistance. We show that disrupting a top candidate from the screens, the mitochondrial protease DegP2, lowers porphyrin levels and decreases DHA susceptibility, without significantly altering parasite fitness in culture. Deleting the homologous gene in P. falciparum, PfDegP, similarly lowers heme levels and DHA susceptibility. These results expose the vulnerability of heme metabolism to genetic perturbations that can lead to increased survival in the presence of DHA.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos/genética , Testes Genéticos/métodos , Heme/genética , Heme/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Técnicas de Inativação de Genes , Humanos , Malária Falciparum/tratamento farmacológico , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Toxoplasma/efeitos dos fármacos , Toxoplasma/genética
11.
PLoS Pathog ; 16(8): e1008705, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32853291

RESUMO

The recent outbreak of human infections caused by SARS-CoV-2, the third zoonotic coronavirus has raised great public health concern globally. Rapid and accurate diagnosis of this novel pathogen posts great challenges not only clinically but also technologically. Metagenomic next-generation sequencing (mNGS) and reverse-transcription PCR (RT-PCR) have been the most commonly used molecular methodologies. However, each has their own limitations. In this study, we developed an isothermal, CRISPR-based diagnostic for COVID-19 with near single-copy sensitivity. The diagnostic performances of all three technology platforms were also compared. Our study aimed to provide more insights into the molecular detection of SARS-CoV-2, and also to present a novel diagnostic option for this new emerging virus.


Assuntos
Betacoronavirus/genética , Sistemas CRISPR-Cas/genética , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/genética , Pneumonia Viral/diagnóstico , Pneumonia Viral/genética , Bactérias/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Genes Virais/genética , Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Técnicas de Diagnóstico Molecular/economia , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/economia , Técnicas de Amplificação de Ácido Nucleico/métodos , Pandemias , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade
13.
Nat Commun ; 11(1): 4077, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796846

RESUMO

Double-strand breaks (DSBs) are the most toxic type of DNA lesions. Cells repair these lesions using either end protection- or end resection-coupled mechanisms. To study DSB repair choice, we present the Color Assay Tracing-Repair (CAT-R) to simultaneously quantify DSB repair via end protection and end resection pathways. CAT-R introduces DSBs using CRISPR/Cas9 in a tandem fluorescent reporter, whose repair distinguishes small insertions/deletions from large deletions. We demonstrate CAT-R applications in chemical and genetic screens. First, we evaluate 21 compounds currently in clinical trials which target the DNA damage response. Second, we examine how 417 factors involved in DNA damage response influence the choice between end protection and end resection. Finally, we show that impairing nucleotide excision repair favors error-free repair, providing an alternative way for improving CRISPR/Cas9-based knock-ins. CAT-R is a high-throughput, versatile assay to assess DSB repair choice, which facilitates comprehensive studies of DNA repair and drug efficiency testing.


Assuntos
Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas Mutadas de Ataxia Telangiectasia/genética , Ciclo Celular , Sobrevivência Celular , Dano ao DNA , Reparo do DNA por Junção de Extremidades , Avaliação Pré-Clínica de Medicamentos , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Poli(ADP-Ribose) Polimerase-1/genética
14.
Nat Commun ; 11(1): 4344, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859906

RESUMO

Self-propagating drive systems are capable of causing non-Mendelian inheritance. Here, we report a drive system in yeast referred to as a chromosome drive that eliminates the target chromosome via CRISPR-Cas9, enabling the transmission of the desired chromosome. Our results show that the entire Saccharomyces cerevisiae chromosome can be eliminated efficiently through only one double-strand break around the centromere via CRISPR-Cas9. As a proof-of-concept experiment of this CRISPR-Cas9 chromosome drive system, the synthetic yeast chromosome X is completely eliminated, and the counterpart wild-type chromosome X harboring a green fluorescent protein gene or the components of a synthetic violacein pathway are duplicated by sexual reproduction. We also demonstrate the use of chromosome drive to preferentially transmit complex genetic traits in yeast. Chromosome drive enables entire chromosome elimination and biased inheritance on a chromosomal scale, facilitating genomic engineering and chromosome-scale genetic mapping, and extending applications of self-propagating drives.


Assuntos
Sistemas CRISPR-Cas , Cromossomos/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Saccharomyces cerevisiae/genética , Centrômero , Indóis , Redes e Vias Metabólicas/genética , Saccharomyces cerevisiae/metabolismo , Biologia Sintética/métodos , Termotolerância/genética , Sequenciamento Completo do Genoma
15.
Nat Commun ; 11(1): 4050, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792485

RESUMO

Regulatory networks describe the hierarchical relationship between transcription factors, associated proteins, and their target genes. Regulatory networks respond to environmental and genetic perturbations by reprogramming cellular metabolism. Here we design, construct, and map a comprehensive regulatory network library containing 110,120 specific mutations in 82 regulators expected to perturb metabolism. We screen the library for different targeted phenotypes, and identify mutants that confer strong resistance to various inhibitors, and/or enhanced production of target compounds. These improvements are identified in a single round of selection, showing that the regulatory network library is universally applicable and is convenient and effective for engineering targeted phenotypes. The facile construction and mapping of the regulatory network library provides a path for developing a more detailed understanding of global regulation in E. coli, with potential for adaptation and use in less-understood organisms, expanding toolkits for future strain engineering, synthetic biology, and broader efforts.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Edição de Genes/métodos , Engenharia Metabólica/métodos , Biologia Sintética/métodos , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/fisiologia
16.
Nat Commun ; 11(1): 4072, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792663

RESUMO

Cpf1-linked base editors broaden the targeting scope of programmable cytidine deaminases by recognizing thymidine-rich protospacer-adjacent motifs (PAM) without inducing DNA double-strand breaks (DSBs). Here we present an unbiased in vitro method for identifying genome-wide off-target sites of Cpf1 base editors via whole genome sequencing. First, we treat human genomic DNA with dLbCpf1-BE ribonucleoprotein (RNP) complexes, which convert C-to-U at on-target and off-target sites and, then, with a mixture of E. coli uracil DNA glycosylase (UDG) and DNA glycosylase-lyase Endonuclease VIII, which removes uracil and produces single-strand breaks (SSBs) in vitro. Whole-genome sequencing of the resulting digested genome (Digenome-seq) reveals that, on average, dLbCpf1-BE induces 12 SSBs in vitro per crRNA in the human genome. Off-target sites with an editing frequency as low as 0.1% are successfully identified by this modified Digenome-seq method, demonstrating its high sensitivity. dLbCpf1-BEs and LbCpf1 nucleases often recognize different off-target sites, calling for independent analysis of each tool.


Assuntos
Citidina/metabolismo , Endonucleases/metabolismo , Sequenciamento Completo do Genoma/métodos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Citidina/genética , DNA/genética , DNA/metabolismo , Endonucleases/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Edição de Genes , Genoma Humano/genética , Células HEK293 , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , RNA Guia/genética
17.
Nat Commun ; 11(1): 4132, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807781

RESUMO

Precise genome editing using CRISPR-Cas9 is a promising therapeutic avenue for genetic diseases, although off-target editing remains a significant safety concern. Guide RNAs shorter than 16 nucleotides in length effectively recruit Cas9 to complementary sites in the genome but do not permit Cas9 nuclease activity. Here we describe CRISPR Guide RNA Assisted Reduction of Damage (CRISPR GUARD) as a method for protecting off-targets sites by co-delivery of short guide RNAs directed against off-target loci by competition with the on-target guide RNA. CRISPR GUARD reduces off-target mutagenesis while retaining on-target editing efficiencies with Cas9 and base editor. However, we discover that short guide RNAs can also support base editing if they contain cytosines within the deaminase activity window. We explore design rules and the universality of this method through in vitro studies and high-throughput screening, revealing CRISPR GUARD as a rapidly implementable strategy to improve the specificity of genome editing for most genomic loci. Finally, we create an online tool for CRISPR GUARD design.


Assuntos
Edição de Genes/métodos , RNA Guia/metabolismo , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/fisiologia , Humanos , Mutagênese/genética , Mutagênese/fisiologia , RNA Guia/genética
18.
Nat Commun ; 11(1): 4131, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807807

RESUMO

Recent outbreaks of viral hemorrhagic fevers (VHFs), including Ebola virus disease (EVD) and Lassa fever (LF), highlight the urgent need for sensitive, deployable tests to diagnose these devastating human diseases. Here we develop CRISPR-Cas13a-based (SHERLOCK) diagnostics targeting Ebola virus (EBOV) and Lassa virus (LASV), with both fluorescent and lateral flow readouts. We demonstrate on laboratory and clinical samples the sensitivity of these assays and the capacity of the SHERLOCK platform to handle virus-specific diagnostic challenges. We perform safety testing to demonstrate the efficacy of our HUDSON protocol in heat-inactivating VHF viruses before SHERLOCK testing, eliminating the need for an extraction. We develop a user-friendly protocol and mobile application (HandLens) to report results, facilitating SHERLOCK's use in endemic regions. Finally, we successfully deploy our tests in Sierra Leone and Nigeria in response to recent outbreaks.


Assuntos
Ebolavirus/patogenicidade , Doença pelo Vírus Ebola/diagnóstico , Febre Lassa/diagnóstico , Vírus Lassa/patogenicidade , Anticorpos Antivirais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Ebolavirus/genética , Doença pelo Vírus Ebola/virologia , Febre Lassa/virologia , Vírus Lassa/genética
19.
Proc Natl Acad Sci U S A ; 117(33): 20109-20116, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747526

RESUMO

Herpesviruses are ubiquitous human pathogens that cause a wide range of health complications. Currently, there is an incomplete understanding of cellular factors that contribute to herpesvirus infection. Here, we report an antiviral necroptosis-based genetic screen to identify novel host cell factors required for infection with the ß-herpesvirus murine cytomegalovirus (MCMV). Our genome-wide CRISPR-based screen harnessed the capacity of herpesvirus mutants that trigger antiviral necroptotic cell death upon early viral gene expression. Vascular endothelial growth factor (VEGF) and semaphorin-binding receptor Neuropilin-1 (Nrp-1) emerge as crucial determinants of MCMV infection. We find that elimination of Nrp-1 impairs early viral gene expression and reduces infection rates in endothelial cells, fibroblasts, and macrophages. Furthermore, preincubation of virus with soluble Nrp-1 dramatically inhibits infection by reducing virus attachment. Thus, Nrp-1 is a key determinant of the initial phase of MCMV infection.


Assuntos
Infecções por Citomegalovirus/metabolismo , Muromegalovirus/metabolismo , Necroptose/fisiologia , Neuropilina-1/metabolismo , Animais , Linhagem Celular , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Infecções por Citomegalovirus/genética , Deleção de Genes , Regulação Viral da Expressão Gênica , Camundongos , Muromegalovirus/genética , Neuropilina-1/genética
20.
PLoS One ; 15(8): e0235942, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804931

RESUMO

Genome editing is now widely used in plant science for both basic research and molecular crop breeding. The clustered regularly interspaced short palindromic repeats (CRISPR) technology, through its precision, high efficiency and versatility, allows for editing of many sites in plant genomes. This system has been highly successful to produce knock-out mutants through the introduction of frameshift mutations due to error-prone repair pathways. Nevertheless, recent new CRISPR-based technologies such as base editing and prime editing can generate precise and on demand nucleotide conversion, allowing for fine-tuning of protein function and generating gain-of-function mutants. However, genome editing through CRISPR systems still have some drawbacks and limitations, such as the PAM restriction and the need for more diversity in CRISPR tools to mediate different simultaneous catalytic activities. In this study, we successfully used the CRISPR-Cas9 system from Staphylococcus aureus (SaCas9) for the introduction of frameshift mutations in the tetraploid genome of the cultivated potato (Solanum tuberosum). We also developed a S. aureus-cytosine base editor that mediate nucleotide conversions, allowing for precise modification of specific residues or regulatory elements in potato. Our proof-of-concept in potato expand the plant dicot CRISPR toolbox for biotechnology and precision breeding applications.


Assuntos
Proteína 9 Associada à CRISPR/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Mutação INDEL , Solanum tuberosum/genética , Staphylococcus aureus/enzimologia , Sistemas CRISPR-Cas , Mutação da Fase de Leitura , Edição de Genes/métodos , Genoma de Planta , Plasmídeos/genética , Staphylococcus aureus/genética
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