ABSTRACT
Resumen El desarrollo de tecnologías para la edición del genoma ha abierto la posibilidad de apuntar directamente y modificar secuencias genómicas en casi todo tipo de células eucariotas. La edición del genoma ha ampliado nuestra capacidad para dilucidar la contribución de la genética a las enfermedades al promover la creación de modelos celulares y animales más precisos de procesos patológicos y ha comenzado a mostrar su potencial en una variedad de campos, que van desde la investigación básica hasta la biotecnología aplicada y biomédica. Entre estas tecnologías, el uso de las repeticiones palindrómicas cortas agrupadas regularmente espaciadas ha acelerado, en gran medida, el progreso de la edición de genes desde el concepto hasta la práctica clínica, generando, además, interés debido, no solo a su precisión y eficiencia, sino también a la rapidez y a los costos necesarios para su implementación en comparación con otras tecnologías de edición genómica. En esta revisión se presenta información recabada de publicaciones indexadas en la base de datos PubMed que se encontraron mediante el uso de palabras claves asociadas con la tecnología y que se filtraron para retener solo aquellas con evidencias de avances clínicamente relevantes y que permiten demostrar algunas de las aplicaciones que tiene esta tecnología en la investigación, pronóstico y tratamiento de enfermedades genéticas, cardiovasculares, virales, entre otras; esto con el objetivo de dar a conocer la situación actual de los avances en aplicaciones clínicas de la herramienta CRISPR-Cas y fomentar aún más la investigación en esta tecnología, la cual, tal como se evidencia a lo largo de esta revisión, posee una gran versatilidad y un amplio rango de aplicaciones, lo que ofrece una enorme oportunidad en el campo de la medicina genómica, pero que, a su vez, requiere un mayor fomento en su investigación para mejorar la tecnología y acercarla aún más a consolidar aplicaciones clínicas de uso seguro, confiable y consistente.
Abstract The development of genome editing technologies has opened up the possibility of directly targeting and modifying genomic sequences in almost all types of eukaryotic cells. Genome editing has expanded our ability to elucidate the contribution of genetics to disease by promoting the creation of more precise cellular and animal models of disease processes and has begun to show its potential in a variety of fields, ranging from basic research to applied and biomedical biotechnology. Among these technologies, the use of clustered regularly spaced short palindromic repeats have greatly accelerated the progress of gene editing from concept to clinical practice, further generating interest due not only to its precision and efficiency, but also to the speed and costs required for its implementation compared to other genomic editing methods. This review presents information collected from indexed publications in the PubMed database that were found by using keywords associated with the technology and filtered to retain only those with evidence of clinically relevant advances that demonstrate some of the applications that this technology has in research, prognosis, and treatment of genetic, cardiovascular, and viral diseases, among others; this with the aim of show the current situation of advances in clinical applications of the CRISPR-Cas tool and further encourage research in this technology, which, as evidenced throughout this review, has a great versatility and a wide range of applications, which offers an enormous opportunity in the field of genomic medicine but which, in turn, requires greater support in its research to improve the technology and bring it even closer to consolidating clinical applications of safe, reliable and consistent use.
Subject(s)
Humans , Genetic Therapy/trends , CRISPR-Cas Systems/genetics , Disease/genetics , Genetic Techniques , Genetics/historyABSTRACT
CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein) is widely used in the field of livestock breeding. However, its low efficiency, untargeted cutting and low safety have greatly hampered its use for introducing single base mutations in livestock breeding. Single base editing, as a new gene editing tool, can directly replace bases without introducing double strand breaks. Single base editing shows high efficiency and strong specificity, and provides a simpler and more effective method for precise gene modification in livestock breeding. This paper introduces the principle and development of single base editing technology and its application in livestock breeding.
Subject(s)
Animals , Gene Editing , CRISPR-Cas Systems/genetics , Livestock/genetics , Mutation , TechnologyABSTRACT
Rapid and accurate detection technologies are crucial for disease prevention and control. In particular, the COVID-19 pandemic has posed a great threat to our society, highlighting the importance of rapid and highly sensitive detection techniques. In recent years, CRISPR/Cas-based gene editing technique has brought revolutionary advances in biotechnology. Due to its fast, accurate, sensitive, and cost-effective characteristics, the CRISPR-based nucleic acid detection technology is revolutionizing molecular diagnosis. CRISPR-based diagnostics has been applied in many fields, such as detection of infectious diseases, genetic diseases, cancer mutation, and food safety. This review summarized the advances in CRISPR-based nucleic acid detection systems and its applications. Perspectives on intelligent diagnostics with CRISPR-based nucleic acid detection and artificial intelligence were also provided.
Subject(s)
Humans , CRISPR-Cas Systems/genetics , COVID-19/genetics , Pandemics , Artificial Intelligence , Nucleic AcidsABSTRACT
The CRISPR-Cas9 system is composed of a clustered regularly interspaced short palindromic repeat (CRISPR) and its associated proteins, which are widely present in bacteria and archaea, serving as a specific immune protection against viral and phage secondary infections. CRISPR-Cas9 technology is the third generation of targeted genome editing technologies following zinc finger nucleases (ZFNs) and transcription activator like effector nucleases (TALENs). The CRISPR-Cas9 technology is now widely used in various fields. Firstly, this article introduces the generation, working mechanism and advantages of CRISPR-Cas9 technology; secondly, it reviews the applications of CRISPR-Cas9 technology in gene knockout, gene knock-in, gene regulation and genome in breeding and domestication of important food crops such as rice, wheat, maize, soybean and potato. Finally, the article summarizes the current problems and challenges encountered by CRISPR-Cas9 technology and prospects future development and application of CRISPR-Cas9 technology.
Subject(s)
Gene Editing , CRISPR-Cas Systems/genetics , Plant Breeding , Crops, Agricultural/genetics , TechnologyABSTRACT
The CRISPR (clustered regularly interspaced short palindromic repeats)-Cas (CRISPR associated proteins) system is an adaptive immune system of bacteria and archaea against phages, plasmids and other exogenous genetic materials. The system uses a special RNA (CRISPR RNA, crRNA) guided endonuclease to cut the exogenous genetic materials complementary to crRNA, thus blocking the infection of exogenous nucleic acid. According to the composition of the effector complex, CRISPR-Cas system can be divided into two categories: class 1 (including type Ⅰ, Ⅳ, and Ⅲ) and class 2 (including type Ⅱ, Ⅴ, and Ⅵ). Several CRISPR-Cas systems have been found to have very strong ability to specifically target RNA editing, such as type Ⅵ CRISPR-Cas13 system and type Ⅲ CRISPR-Cas7-11 system. Recently, several systems have been widely used in the field of RNA editing, making them a powerful tool for gene editing. Understanding the composition, structure, molecular mechanism and potential application of RNA-targeting CRISPR-Cas systems will facilitate the mechanistic research of this system and provide new ideas for developing gene editing tools.
Subject(s)
CRISPR-Cas Systems/genetics , RNA/genetics , Bacteria/genetics , Gene Editing , ArchaeaABSTRACT
The CRISPR/Cas systems comprising the clustered regularly interspaced short palindromic repeats (CRISPR) and its associated Cas protein is an acquired immune system unique to archaea or bacteria. Since its development as a gene editing tool, it has rapidly become a popular research direction in the field of synthetic biology due to its advantages of high efficiency, precision, and versatility. This technique has since revolutionized the research of many fields including life sciences, bioengineering technology, food science, and crop breeding. Currently, the single gene editing and regulation techniques based on CRISPR/Cas systems have been increasingly improved, but challenges still exist in the multiplex gene editing and regulation. This review focuses on the development and application of multiplex gene editing and regulation techniques based on the CRISPR/Cas systems, and summarizes the techniques for multiplex gene editing or regulation within a single cell or within a cell population. This includes the multiplex gene editing techniques developed based on the CRISPR/Cas systems with double-strand breaks; or with single-strand breaks; or with multiple gene regulation techniques, etc. These works have enriched the tools for the multiplex gene editing and regulation and contributed to the application of CRISPR/Cas systems in the multiple fields.
Subject(s)
Gene Editing , CRISPR-Cas Systems/genetics , Bacteria/genetics , Archaea , BioengineeringABSTRACT
Gene editing technology is a genetic operation technology that can modify the DNA sequence at the genomic level. The precision gene editing technology based on CRISPR/Cas9 system is a gene editing technology that is easy to operate and widely used. Unlike the traditional CRISPR/Cas9 system, the precision gene editing technology can perform site-directed mutation of genes without DNA template. This review summarizes the recent development of precision gene editing technology based on CRISPR/Cas9, and prospects the challenges and opportunities of this technology.
Subject(s)
Gene Editing , CRISPR-Cas Systems/genetics , Mutation , GenomeABSTRACT
The generation of a tau-V337M point mutation mouse model using gene editing technology can provide an animal model with fast disease progression and more severe symptoms, which facilitate the study of pathogenesis and treatment of Alzheimer's disease (AD). In this study, single guide RNAs (sgRNA) and single-stranded oligonucleotides (ssODN) were designed and synthesized in vitro. The mixture of sgRNA, Cas9 protein and ssODN was microinjected into the zygotes of C57BL/6J mice. After DNA cutting and recombination, the site homologous to human 337 valine (GTG) in exon 11 was mutated into methionine (ATG). In order to improve the efficiency of recombination, a Rad51 protein was added. The female mice mated with the nonvasectomy male mice were used as the surrogates. Subsequently, the 2-cell stage gene edited embryos were transferred into the unilateral oviduct, and the F0 tau-V337M mutation mice were obtained. Higher mutation efficiency could be obtained by adding Rad51 protein. The F0 tau-V337M point mutation mice can pass the mutation on to the F1 generation mice. In conclusion, this study successfully established the first tau-V337M mutation mouse by using Cas9, ssODN and Rad51. These results provide a new method for developing AD mice model which can be used in further research on the pathogenesis and treatment of AD.
Subject(s)
Animals , Male , Female , Mice , Humans , CRISPR-Cas Systems/genetics , RNA, Guide, CRISPR-Cas Systems , Rad51 Recombinase/genetics , Mice, Inbred C57BL , Disease Models, Animal , Recombination, GeneticABSTRACT
Traditional pig breeding has a long cycle and high cost, and there is an urgent need to use new technologies to revitalize the pig breeding industry. The recently emerged CRISPR/Cas9 genome editing technique shows great potential in pig genetic improvement, and has since become a research hotspot. Base editor is a new base editing technology developed based on the CRISPR/Cas9 system, which can achieve targeted mutation of a single base. CRISPR/Cas9 technology is easy to operate and simple to design, but it can lead to DNA double strand breaks, unstable gene structures, and random insertion and deletion of genes, which greatly restricts the application of this technique. Different from CRISPR/Cas9 technique, the single base editing technique does not produce double strand breaks. Therefore, it has higher accuracy and safety for genome editing, and is expected to advance the pig genetic breeding applications. This review summarized the working principle and shortcomings of CRISPR/Cas9 technique, the development and advantages of single base editing, the principles and application characteristics of different base editors and their applications in pig genetic improvement, with the aim to facilitate genome editing-assisted genetic breeding of pig.
Subject(s)
Animals , Swine/genetics , Gene Editing , CRISPR-Cas Systems/genetics , DNA Breaks, Double-StrandedABSTRACT
During the gene editing process mediated by CRISPR/Cas9, precise genome editing and gene knock-in can be achieved by the homologous recombination of double-stranded DNA (dsDNA) donor template. However, the low-efficiency of homologous recombination in eukaryotic cells hampers the development and application of this gene editing strategy. Here, we developed a novel CRISPR/Cas9-hLacI donor adapting system (DAS) to enhance the dsDNA-templated gene editing, taking the advantage of the specific binding of the LacI repressor protein and the LacO operator sequence derived for the Escherichia coli lactose operon. The codon-humanized LacI gene was fused as an adaptor to the Streptococcus pyogenes Cas9 (SpCas9) and Staphylococcus lugdunensis Cas9 (SlugCas9-HF) genes, and the LacO operator sequence was used as the aptamer and linked to the dsDNA donor template by PCR. The Cas9 nuclease activity after the fusion and the homology-directed repair (HDR) efficiency of the LacO-linked dsDNA template were firstly examined using surrogate reporter assays with the corresponding reporter vectors. The CRISPR/Cas9-hLacI DASs mediated genome precise editing were further checked, and we achieved a high efficiency up to 30.5% of precise editing at the VEGFA locus in HEK293T cells by using the CRISPR/SlugCas9-hLacI DAS. In summary, we developed a novel CRISPR/Cas9-hLacI DAS for dsDNA-templated gene editing, which enriches the CRISPR/Cas9-derived gene editing techniques and provides a novel tool for animal molecular design breeding researches.
Subject(s)
Humans , Animals , Gene Editing , CRISPR-Cas Systems/genetics , HEK293 Cells , Homologous Recombination , DNAABSTRACT
This study aimed to explore the expression changes of VASA gene in sheep testis development and to construct VASA gene knock-in vector to prepare for the study on the differentiation of sheep germ cells in vitro. The testicular tissues of 3-month-old (3M) and 9-month-old (9M) sheep which represent immature and mature stages, respectively, were collected. The differential expression of VASA gene was analyzed by quantitative real-time PCR (qPCR) and Western blotting, and the location of VASA gene was detected by immunohistochemistry. The sgRNA targeting the VASA gene was designed and homologous recombination vectors were constructed by PCR. Subsequently, plasmids were transferred into sheep ear fibroblasts. The VASA gene was activated in combination with CRISPR/dCas9 technology to further verify the efficiency of the vector. The results showed that the expression level of VASA gene increased significantly with the development of sheep testis (P < 0.01), and was mainly located in spermatocytes and round spermatids. The knock-in vector of VASA gene was constructed by CRISPR/Cas9 system, and the Cas9-gRNA vector and pEGFP-PGK puro-VASA vector were transfected into ear fibroblasts. After CRISPR/dCas9 system was activated, ear fibroblasts successfully expressed VASA gene. The results suggest that VASA gene plays a potential function in sheep testicular development and spermatogenesis, and the VASA gene knock-in vector can be constructed in vitro through the CRISPR/Cas9 system. Our results provided effective research tools for further research of germ cell development and differentiation.
Subject(s)
Male , Animals , Sheep/genetics , CRISPR-Cas Systems/genetics , Gene Knock-In Techniques , RNA, Guide, CRISPR-Cas Systems , Plasmids , Germ CellsABSTRACT
The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system has been widely used for genome engineering and transcriptional regulation in many different organisms. Current CRISPR-activation (CRISPRa) platforms often require multiple components because of inefficient transcriptional activation. Here, we fused different phase-separation proteins to dCas9-VPR (dCas9-VP64-P65-RTA) and observed robust increases in transcriptional activation efficiency. Notably, human NUP98 (nucleoporin 98) and FUS (fused in sarcoma) IDR domains were best at enhancing dCas9-VPR activity, with dCas9-VPR-FUS IDR (VPRF) outperforming the other CRISPRa systems tested in this study in both activation efficiency and system simplicity. dCas9-VPRF overcomes the target strand bias and widens gRNA designing windows without affecting the off-target effect of dCas9-VPR. These findings demonstrate the feasibility of using phase-separation proteins to assist in the regulation of gene expression and support the broad appeal of the dCas9-VPRF system in basic and clinical applications.
Subject(s)
Humans , Transcriptional Activation , RNA, Guide, CRISPR-Cas Systems , Gene Expression Regulation , CRISPR-Cas Systems/geneticsABSTRACT
Modelos celulares são muito utilizados na pesquisa experimental e, idealmente, constituem o primeiro nível de modelo de estudo. A utilização de modelos celulares permite, por exemplo, a primeira avaliação de tolerabilidade e de segurança de fármacos e tratamentos experimentais, além de permitir a redução do uso de animais de experimentação. Muito conhecimento já foi gerado cultivando células de pacientes com patologias diversas de doenças genéticas hereditárias a câncer. Entretanto, muitos pesquisadores não têm acesso às células de pacientes. O desenvolvimento da técnica de edição de genes CRISPR/Cas9, na última década, tornou a geração de modelos celulares muito mais acessível para pesquisadores do mundo todo, por permitir a edição de genes de interesse em múltiplos tipos celulares, incluindo células imortalizadas e de fácil cultivo. Nesse contexto, este artigo descreve como a edição gênica funciona e como utilizar essa ferramenta in vitro para produzir modelos celulares para estudo. Nosso objetivo é apresentar essa metodologia a laboratórios que tenham interesse em implementar edição genômica em seus projetos de pesquisa.
Cellular models are extensively utilized in experimental research and serve as the primary level of study. These models enable the initial assessment of drug and treatment tolerability and safety, while also reducing the need for experimental animals. Significant knowledge has been acquired by cultivating cells from patients with various pathologies, ranging from hereditary genetic disorders to cancer. However, access to such cells is limited for many researchers. The advent of the CRISPR/Cas9 gene editing technique in the past decade has revolutionized the generation of cellular models, making it more accessible to researchers worldwide. This technique allows for the targeted editing of genes of interest in multiple cell types, including immortalized cells. This manuscript aims to provide a comprehensive overview of gene editing, while also being a guide for conducting initial experiments, with a primary focus on the development of cell models. Our primary goal is to introduce these techniques to labs in Brazil that are not familiar with them.
Subject(s)
Genome, Human/genetics , CRISPR-Cas Systems/genetics , Gene Editing/methods , Base Sequence , Transfection , Cell Line , MutationABSTRACT
A new wave of research has been inspired by the CRISPR-Cas system with respect to their application in genome editing. The CRISPR-Cas system can not only be applied in gene knockout and insertion, but also be used in base editing, transcriptional regulation and recombination of gene clusters. However, the low efficiency of homology-directed repair (HDR) limits its application. Unlike the CRISPR-Cas system, mobile genetic elements (MGE) can insert DNA fragments into cell chromosomes without the aid of HDR. Recently, it is reported that CRISPR-related transposable elements can guide targeted DNA insertion. Their transposition mechanisms and reprogramming abilities have brought novel opportunities to the development of this field. This review summarized the research progress and application development of natural CRISPR-related transposable elements in recent years, as well as the applications of fused dCas9-transposase. It proposed the application prospects and potential challenges of CRISPR-related transposable elements in the future, which provided a reference for the development direction of gene editing tools.
Subject(s)
DNA Transposable Elements/genetics , Gene Editing , CRISPR-Cas Systems/geneticsABSTRACT
Aspergillus niger is an important industrial strain which has been widely used for production of enzymes and organic acids. Genome modification of A. niger is required to further improve its potential for industrial production. CRISPR/Cas9 is a widely used genome editing technique for A. niger, but its application in industrial strains modification is hampered by the need for integration of a selection marker into the genome or low gene editing efficiency. Here we report a highly efficient marker-free genome editing method for A. niger based on CRISPR/Cas9 technique. Firstly, we constructed a co-expression plasmid of sgRNA and Cas9 with a replication initiation region fragment AMA1 (autonomously maintained in Aspergillus) by using 5S rRNA promoter which improved sgRNA expression. Meanwhile, a strain deficient in non-homologous end-joining (NHEJ) was developed by knocking out the kusA gene. Finally, we took advantage of the instability of plasmid containing AMA1 fragment to cure the co-expression plasmid containing sgRNA and Cas9 through passaging on non-selective plate. With this method, the efficiency of gene editing reached 100% when using maker-free donor DNA with a short homologous arm of 20 bp. This method may facilitate investigation of gene functions and construction of cell factories for A. niger.
Subject(s)
Gene Editing , Aspergillus niger/genetics , CRISPR-Cas Systems/genetics , Plasmids/geneticsABSTRACT
Recent advances in genome editing, especially CRISPR-Cas nucleases, have revolutionized both laboratory research and clinical therapeutics. CRISPR-Cas nucleases, together with the DNA damage repair pathway in cells, enable both genetic diversification by classical non-homologous end joining (c-NHEJ) and precise genome modification by homology-based repair (HBR). Genome editing in zygotes is a convenient way to edit the germline, paving the way for animal disease model generation, as well as human embryo genome editing therapy for some life-threatening and incurable diseases. HBR efficiency is highly dependent on the DNA donor that is utilized as a repair template. Here, we review recent progress in improving CRISPR-Cas nuclease-induced HBR in mammalian embryos by designing a suitable DNA donor. Moreover, we want to provide a guide for producing animal disease models and correcting genetic mutations through CRISPR-Cas nuclease-induced HBR in mammalian embryos. Finally, we discuss recent developments in precise genome-modification technology based on the CRISPR-Cas system.
Subject(s)
Animals , CRISPR-Cas Systems/genetics , DNA/genetics , Embryo, Mammalian/metabolism , Endonucleases/metabolism , Gene Editing , Mammals/metabolismABSTRACT
The CRISPR/Cas9 based prime editing (PE) technique enables all 12 types of base substitutions and precise small DNA deletions or insertions without generating DNA double-strand breaks. Prime editing has been successfully applied in plants and plays important roles in plant precision breeding. Although plant prime editing (PPE) can substantially expand the scope and capabilities of precise genome editing in plants, its editing efficiency still needs to be further improved. Here, we review the development of PPE technique, and introduce structural composition, advantages and limitations of PPE. Strategies to improve the PPE editing efficiency, including the Tm-directed PBS length design, the RT template length, the dual-pegRNA strategy, the PlantPegDesigner website, and the strategies for optimizing the target proteins of PPE, were highlighted. Finally, the prospects of future development and application of PPE were discussed.
Subject(s)
CRISPR-Cas Systems/genetics , DNA , Gene Editing , Genome, Plant/genetics , Plant Breeding , Plants/geneticsABSTRACT
Gluconobacter oxydans are widely used in industrial due to its ability of oxidizing carbohydrate rapidly. However, the limited gene manipulation methods and less of efficient gene editing tools impose restrictions on its application in industrial production. In recent years, the clustered regularly interspaced short palindromic repeats (CRISPR) system has been widely used in genome editing and transcriptional regulation which improves the efficiency of genome editing greatly. Here we constructed a CRISPR/dCpf1-mediated gene transcriptional repression system, the expression of a nuclease inactivation Cpf1 protein (dCpf1) in Gluconobacter oxydans together with a 19 nt direct repeats showed effective repression in gene transcription. This system in single gene repression had strong effect and the relative repression level had been increased to 97.9%. While it could be applied in multiplex gene repression which showed strong repression ability at the same time. Furthermore, this system was used in the metabolic pathway of L-sorbose and the regulatory of respiratory chain. The development of CRISPR transcriptional repression system effectively covered the shortage of current gene regulation methods in G. oxydans and provided an efficient gene manipulation tool for metabolic engineering modification in G. oxydans.
Subject(s)
CRISPR-Cas Systems/genetics , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Gene Editing , Gene Expression , Gluconobacter oxydans/genetics , Metabolic EngineeringABSTRACT
As a new CRISPR/Cas-derived genome engineering technology, base editing combines the target specificity of CRISPR/Cas and the catalytic activity of nucleobase deaminase to install point mutations at target loci without generating DSBs, requiring exogenous template, or depending on homologous recombination. Recently, researchers have developed a variety of base editing tools in the important industrial strain Corynebacterium glutamicum, and achieved simultaneous editing of two and three genes. However, the multiplex base editing based on CRISPR/Cas9 is still limited by the complexity of multiple sgRNAs, interference of repeated sequence and difficulty of target loci replacement. In this study, multiplex base editing in C. glutamicum was optimized by the following strategies. Firstly, the multiple sgRNA expression cassettes based on individual promoters/terminators was optimized. The target loci can be introduced and replaced rapidly by using a template plasmid and Golden Gate method, which also avoids the interference of repeated sequence. Although the multiple sgRNAs structure is still complicated, the editing efficiency of this strategy is the highest. Then, the multiple gRNA expression cassettes based on Type Ⅱ CRISPR crRNA arrays and tRNA processing were developed. The two strategies only require one single promoter and terminator, and greatly simplify the structure of the expression cassette. Although the editing efficiency has decreased, both methods are still applicable. Taken together, this study provides a powerful addition to the genome editing toolbox of C. glutamicum and facilitates genetic modification of this strain.
Subject(s)
CRISPR-Cas Systems/genetics , Corynebacterium glutamicum/metabolism , Gene Editing , Plasmids , /metabolismABSTRACT
To investigate the cellular target selectivity of small molecules targeting thioredoxin reductase 1, we reported the construction and functional research of a stable TrxR1 gene (encode thioredoxin reductase 1) knockout HCT-116 cell line. We designed and selected TrxR1 knockout sites according to the TrxR1 gene sequence and CRISPR/Cas9 target designing principles. SgRNA oligos based on the selected TrxR1 knockout sites were obtained. Next, we constructed knockout plasmid by cloning the sgRNA into the pCasCMV-Puro-U6 vector. After transfection of the plasmid into HCT-116 cells, TrxR1 knockout HCT-116 cells were selected using puromycin resistance. The TrxR1 knockout efficiency was identified and verified by DNA sequencing, immunoblotting, TRFS-green fluorescent probe, and cellular TrxR1 enzyme activity detection. Finally, the correlation between TrxR1 expression and cellular effects of drugs specifically targeting TrxR1 was investigated by CCK-8 assay. The results demonstrated that the knockout plasmid expressing the sgRNA effectively knocked-out TrxR1 gene within HCT-116 cells, and no expression of TrxR1 protein could be observed in stable TrxR1 knockout HCT-116 (HCT116-TrxR1-KO) cells. The TrxR1-targeting inhibitor auranofin did not show any inhibitory activity against either cellular TrxR1 enzyme activity or cell proliferation. Based on these results, we conclude that a stable TrxR1 gene knockout HCT-116 cell line was obtained through CRISPR/Cas9 techniques, which may facilitate investigating the role of TrxR1 in various diseases.