这项工作得到了加拿大卫生研究所（CIHR 365252）、克雷姆比尔基金会和安大略研究基金卓越研究第8轮（RE08-065）的项目赠款的支持。桑帕德·库马尔·洛加坦是加拿大癌症协会奖学金（BC-F-16#31919）的接受者。

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作者没有什么可透露的。

CRISPR/Cas9基因组编辑已广泛应用于体外和体内研究，以研究基因功能和细胞过程。大多数体内研究都利用CRISPR/Cas9基因编辑的细胞移植到动物模型（异种移植或异种移植）。虽然这是研究癌症遗传学和细胞功能的有力工具，但它仍然缺乏原生组织微环境，并可能引起伤害和/或免疫反应。
为了克服这些挑战，几个小组已经率先在体内CRISPR方法产生几个，多路复用的自动鼠标模型...

后基因组时代癌症研究面临的挑战之一是挖掘因果基因突变的大量基因组数据，并识别基因网络中可以针对治疗的节点。虽然生物信息分析对实现这些目标大有帮助，但建立有效的体外和体内模型是破译生物系统和疾病状态的复杂性和促进药物开发的先决条件。虽然传统的转基因小鼠模型在体内癌症遗传学研究中被广泛使用，但其成本、时间和劳动密集型性质在很大程度上禁止了对现代基因组学解开的数百个假定癌症基因的系统分析。为了克服这一瓶颈，我们结合了先前建立的子宫内注射方法1，2的超声波引导与CRISPR/Cas9（聚集定期间歇短巴林德罗米重复）基因编辑技术3，同时诱导和研究数百个基因在皮肤和单只小鼠口腔的功能丧失突变。
此处描述的方法利用工程扁豆病毒的超声波引导注射到胚胎日E9.5活小鼠胚胎的羊水腔中。含有CRISPR/Cas9成分的扁桃体货物会转导单层表面等体，后者后来导致皮肤和口腔的上皮。皮肤由外表皮组成，其次是地下室膜和真皮。表皮是一种分层上皮，由内基层组成，与地下膜保持接触，具有增殖和干细胞能力。基底层产生上面的分化层，如旋转层、颗粒层和地层角膜层2、4。血统追踪研究表明，这种直接在体内CRISPR/Cas9方法基因操纵组织驻存干细胞在基底层，持续整个成年。由于扁豆病毒可以滴定以在克隆密度下转导E9.5表面细胞，因此这种方法可用于生成含有数千个离散基因克隆的马赛克小鼠。然后，下一代测序可用于以多路复用的方式分析CRISPR/Cas9介质基因消融在这些克隆中的影响。
我们最近使用这种方法评估了484个基因的功能，这些基因显示人类头部和颈部鳞状细胞癌（HNSCC）5的反复突变。HNSCC是一种毁灭性的癌症，死亡率高达40-50%，是全世界第6大最常见的癌症。HNSCC 出现在上气道或口腔的粘膜衬里中，与烟草和酒精消费或人类瘤病毒（ HPV ）感染有关。皮肤鳞状细胞癌（SCC）是皮肤肿瘤，是人类第二常见的癌症。角质SCC和HNSCC在病理学和分子学上非常相似，在TP53、PIK3CA、NOTCH1和HRAS8中出现改变的病例比例很高。虽然只有少数基因在高频下发生变异，但有数百个基因在低频下发生变异（+lt;5%），这种现象通常被称为长尾分布。由于大多数长尾基因缺乏生物或临床验证，我们利用这种体内CRISPR筛选技术，在p53、Pik3ca或Hras中具有敏感突变的肿瘤易发小鼠中模拟这些基因的功能丧失，并发现了几个与p53、Pik3ca或Hras合作的新型肿瘤抑制基因，以触发肿瘤发育5。
在这里，我们描述了一个详细的协议，以产生多路sgRNA扁平CRISPR sgRNA库，并在鼠标表面等体中执行CRISPR/Cas9基因敲除屏幕。值得注意的是，这种方法可以应用于整合其他基因操作技术，如CRISPR激活（CRISPRa）和CRISPR灭活（CRISPRi），或修改为针对小鼠的其他器官系统来研究基因功能。

<table>
	<tbody>
		<tr>
			<td>0.45 micron filter</td>
			<td>Sigma</td>
			<td>S2HVU02RE</td>
			<td></td>
		</tr>
		<tr>
			<td>12k or 92k oligo chip</td>
			<td>Customarray Inc. (Genscript)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>15 cm cell culture plates</td>
			<td>Corning</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>293FT</td>
			<td>Invitrogen</td>
			<td>R70007</td>
			<td></td>
		</tr>
		<tr>
			<td>293NT</td>
			<td>Systems Biosciences</td>
			<td>LV900A-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Alkaline phosphatase</td>
			<td>NEB</td>
			<td>M0290L</td>
			<td></td>
		</tr>
		<tr>
			<td>Amplicillin</td>
			<td>Fisher Scientific</td>
			<td>BP1760-25</td>
			<td></td>
		</tr>
		<tr>
			<td>ATP</td>
			<td>NEB</td>
			<td>9804S</td>
			<td></td>
		</tr>
		<tr>
			<td>BsmBI</td>
			<td>NEB</td>
			<td>R0580L</td>
			<td></td>
		</tr>
		<tr>
			<td>Chromic gut suture</td>
			<td>Covidien</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Deep sequencing (Next-Seq or Hi-Seq)</td>
			<td>Illumina</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>DNA-cleanup kit</td>
			<td>Zymo Research</td>
			<td>D4008</td>
			<td></td>
		</tr>
		<tr>
			<td>DNAesy Blood and Tissue DNA extraction kit</td>
			<td>Qiagen</td>
			<td>69506</td>
			<td></td>
		</tr>
		<tr>
			<td>Endura electrocompetent cells</td>
			<td>Lucigen</td>
			<td>60242-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass Capillaries</td>
			<td>Drummond</td>
			<td>3-000-203-G/X</td>
			<td></td>
		</tr>
		<tr>
			<td>HEK293T cells</td>
			<td>ATCC</td>
			<td>CRL-3216</td>
			<td></td>
		</tr>
		<tr>
			<td>High-Speed Centrifuge</td>
			<td>Beckman Coulter</td>
			<td>MLS-50</td>
			<td></td>
		</tr>
		<tr>
			<td>LB Agar</td>
			<td>Wisent Technologies</td>
			<td>800-011-LG</td>
			<td></td>
		</tr>
		<tr>
			<td>Micropipette puller</td>
			<td>Sutter Instrument</td>
			<td>P97</td>
			<td></td>
		</tr>
		<tr>
			<td>Mineral oil</td>
			<td>Sigma</td>
			<td>M5904</td>
			<td></td>
		</tr>
		<tr>
			<td>Mini-prep plasmid Kit</td>
			<td>Frogga Bio</td>
			<td>PDH300</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse oxygen anaesthesia system</td>
			<td>Visual Sonics</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nanoject II micromanipulator</td>
			<td>Drummond</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>NEBuffer 3.1 (Buffer for BsmBI)</td>
			<td>NEB</td>
			<td>R0580L</td>
			<td></td>
		</tr>
		<tr>
			<td>Needle sharpener</td>
			<td>Sutter Instrument</td>
			<td>BV-10</td>
			<td></td>
		</tr>
		<tr>
			<td>Oligo cleanup kit</td>
			<td>Zymo research</td>
			<td>D4060</td>
			<td></td>
		</tr>
		<tr>
			<td>PAGE purified illumina sequencing primer</td>
			<td>IDT DNA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>PEI (polyethyleneimine)</td>
			<td>Sigma</td>
			<td>408727-100ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Permoplast modeling clay</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Petridish with central opening</td>
			<td>Visual Sonics</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>pMD2.G</td>
			<td>Addgene</td>
			<td>12259</td>
			<td></td>
		</tr>
		<tr>
			<td>psPAX2</td>
			<td>Addgene</td>
			<td>12260</td>
			<td></td>
		</tr>
		<tr>
			<td>Q5 Polymerase 2x Master mix</td>
			<td>NEB</td>
			<td>M0494L</td>
			<td></td>
		</tr>
		<tr>
			<td>Qubit Fluorometric Quantification</td>
			<td>Invitrogen</td>
			<td>Q33327</td>
			<td></td>
		</tr>
		<tr>
			<td>Semicircular Silicone plug</td>
			<td>Corning</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Silicone membrane</td>
			<td>Visual Sonics</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>T4 DNA ligase</td>
			<td>NEB</td>
			<td>M0202L</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultra-centrifuge tubes</td>
			<td>Beckman Coulter</td>
			<td>344058</td>
			<td></td>
		</tr>
		<tr>
			<td>Vevo2000 ultrasound system</td>
			<td>Visual Sonics</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

in vivo crispr/cas9 screening to simultaneously evaluate gene function in mouse skin and oral cavity

转基因小鼠模型 （GEMM） 在评估基因功能、模拟人类疾病以及作为临床前模型评估治疗途径方面发挥了重要作用。然而，它们的时间、劳动和成本密集型性质限制了它们对基因功能进行系统分析的效用。基因组编辑技术的最新进展克服了这些限制，并允许以多路复用和快速的方式在特定小鼠器官内快速生成特定的基因扰动。在这里，我们描述了一种基于CRISPR/Cas9的方法（聚集定期间歇短脑重复），在小鼠皮肤和口腔的上皮产生数千个基因敲除克隆，并提供一个协议，详细说明   在肿瘤抑制基因的直接体内CRISPR屏幕执行必要的步骤。这种方法可以应用于其他器官或其他CRISPR/Cas9技术，如CRISPR激活或CRISPR灭活，以研究基因在组织失落期间或在各种疾病环境中的生物功能。

图1A 显示了寡核苷酸的设计，用于在单个 12k 或 92k 寡头芯片中以经济高效的方式对多个自定义 CRISPR 库进行多路复用。一旦选择 sgRNA（蓝色编码），寡核苷酸将设计为限制位点（橙色 BsmBI）和库特定的 PCR 引物对（绿色编码）。几个库可以通过使用引物对的独特组合来设计，用于在单个寡头芯片中进行多重组合。当 PCR 使用特定的 PCR 底漆对放大库时，始终只包含水负控制，?...

Watch this Scientific Journal Video about In Vivo CRISPR/Cas9 Screening to Simultaneously Evaluate Gene Function in Mouse Skin and Oral Cavity at JoVE.com

In Vivo CRISPR/Cas9 Screening to Simultaneously Evaluate Gene Function in Mouse Skin and Oral Cavity

在这里，我们描述了一种快速和直接的体内CRISPR/Cas9筛查方法，使用超声波引导子宫胚胎扁平注射，同时评估几个基因在皮肤和免疫能力小鼠口腔的功能。

在Vivo CRISPR/Cas9筛查中同时评估小鼠皮肤和口腔中的基因功能

Genetically modified mouse models (GEMM) have been instrumental in assessing gene function, modeling human diseases, and serving as preclinical model to ...

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6.3K 次观看.  Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital. 在这里，我们描述了一种快速和直接的体内CRISPR/Cas9筛查方法，使用超声波引导子宫胚胎扁平注射，同时评估几个基因在皮肤和免疫能力小鼠口腔的功能。

视频: In Vivo CRISPR/Cas9 Screening to Simultaneously Evaluate Gene Function in Mouse Skin and Oral Cavity

QTL Mapping and CRISPR/Cas9 Editing to Identify a Drug Resistance Gene in Toxoplasma gondii

Scientific knowledge is intrinsically linked to available technologies and methods. This article will present two methods that allowed for the identification and verification of a drug resistance gene in the Apicomplexan parasite Toxoplasma gondii, the method of Quantitative Trait Locus (QTL) mapping using a Whole Genome Sequence (WGS) -based genetic map and the method of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 -based gene editing. The approach of QTL mapping allows one to test if there is a correlation between a genomic region(s) and a phenotype. Two datasets are required to run a QTL scan, a genetic map based on the progeny of a recombinant cross and a quantifiable phenotype assessed in each of the progeny of that cross. These datasets are then formatted to be compatible with R/qtl software that generates a QTL scan to identify significant loci correlated with the phenotype. Although this can greatly narrow the search window of possible candidates, QTLs span regions containing a number of genes from which the causal gene needs to be identified. Having WGS of the progeny was critical to identify the causal drug resistance mutation at the gene level. Once identified, the candidate mutation can be verified by genetic manipulation of drug sensitive parasites. The most facile and efficient method to genetically modify T. gondii is the CRISPR/Cas9 system. This system comprised of just 2 components both encoded on a single plasmid, a single guide RNA (gRNA) containing a 20 bp sequence complementary to the genomic target and the Cas9 endonuclease that generates a double-strand DNA break (DSB) at the target, repair of which allows for insertion or deletion of sequences around the break site. This article provides detailed protocols to use CRISPR/Cas9 based genome editing tools to verify the gene responsible for sinefungin resistance and to construct transgenic parasites.

QTL Mapping and CRISPR/Cas9 Editing to Identify a Drug Resistance Gene in Toxoplasma gondii

Details are presented on how QTL mapping with a whole genome sequence based genetic map can be used to identify a drug resistance gene in Toxoplasma gondii and how this can be verified with the CRISPR/Cas9 system that efficiently edits a genomic target, in this case the drug resistance gene.

QTL定位和CRISPR / Cas9编辑识别抗药性基因<em&gt;弓形虫</em

Scientific knowledge is intrinsically linked to available technologies and methods. This article will present two methods that allowed for the ...

科研

遗传学

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

The CRISPR/Cas9 genome engineering system has revolutionized biology by allowing for precise genome editing with little effort. Guided by a single guide RNA (sgRNA) that confers specificity, the Cas9 protein cleaves both DNA strands at the targeted locus. The DNA break can trigger either non-homologous end joining (NHEJ) or homology directed repair (HDR). NHEJ can introduce small deletions or insertions which lead to frame-shift mutations, while HDR allows for larger and more precise perturbations. Here, we present protocols for generating knockout cell lines by coupling established CRISPR/Cas9 methods with two options for downstream selection/screening. The NHEJ approach uses a single sgRNA cut site and selection-independent screening, where protein production is assessed by dot immunoblot in a high-throughput manner. The HDR approach uses two sgRNA cut sites that span the gene of interest. Together with a provided HDR template, this method can achieve deletion of tens of kb, aided by the inserted selectable resistance marker. The appropriate applications and advantages of each method are discussed.

Recent advances in the ability to genetically manipulate somatic cell lines hold great potential for basic and applied research. Here, we present two approaches for CRISPR/Cas9 generated knockout production and screening in mammalian cell lines, with and without the use of selectable markers.

选择依赖和独立生成CRISPR / Cas9介导的哺乳动物细胞基因敲除

The CRISPR/Cas9 genome engineering system has revolutionized biology by allowing for precise genome editing with little effort. Guided by a single guide ...

Primordial Germ Cell Transplantation for CRISPR/Cas9-based Leapfrogging in Xenopus

The creation of mutant lines by genome editing is accelerating genetic analysis in many organisms. CRISPR/Cas9 methods have been adapted for use in the African clawed frog, Xenopus, a longstanding model organism for biomedical research. Traditional breeding schemes for creating homozygous mutant lines with CRISPR/Cas9-targeted mutagenesis have several time-consuming and laborious steps. To facilitate the creation of mutant embryos, particularly to overcome the obstacles associated with knocking out genes that are essential for embryogenesis, a new method called leapfrogging was developed. This technique leverages the robustness of Xenopus embryos to &#34;cut and paste&#34; embryological methods. Leapfrogging utilizes the transfer of primordial germ cells (PGCs) from efficiently-mutagenized donor embryos into PGC-ablated wildtype siblings. This method allows for the efficient mutation of essential genes by creating chimeric animals with wildtype somatic cells that carry a mutant germline. When two F0 animals carrying &#34;leapfrog transplants&#34; (i.e., mutant germ cells) are intercrossed, they produce homozygous, or compound heterozygous, null F1 embryos, thus saving a full generation time to obtain phenotypic data. Leapfrogging also provides a new approach for analyzing maternal effect genes, which are refractory to F0 phenotypic analysis following CRISPR/Cas9 mutagenesis. This manuscript details the method of leapfrogging, with special emphasis on how to successfully perform PGC transplantation.

Primordial Germ Cell Transplantation for CRISPR/Cas9-based Leapfrogging in Xenopus

Genes essential for survival pose technical hurdles for creating mutant lines. Leapfrogging circumvents lethality by combining genome editing with primordial germ cell transplantation to create wild-type animals carrying germline mutations. Leapfrogging also permits the efficient generation of homozygous null mutants in the F1 generation. Here, the transplantation step is demonstrated.

CRISPR/Cas9-based 跳跃的原始生殖细胞移植在爪

The creation of mutant lines by genome editing is accelerating genetic analysis in many organisms. CRISPR/Cas9 methods have been adapted for use in the ...

A Standard Methodology to Examine On-site Mutagenicity As a Function of Point Mutation Repair Catalyzed by CRISPR/Cas9 and SsODN in Human Cells

Combinatorial gene editing using CRISPR/Cas9 and single-stranded oligonucleotides is an effective strategy for the correction of single-base point mutations, which often are responsible for a variety of human inherited disorders. Using a well-established cell-based model system, the point mutation of a single-copy mutant eGFP gene integrated into HCT116 cells has been repaired using this combinatorial approach. The analysis of corrected and uncorrected cells reveals both the precision of gene editing and the development of genetic lesions, when indels are created in uncorrected cells in the DNA sequence surrounding the target site. Here, the specific methodology used to analyze this combinatorial approach to the gene editing of a point mutation, coupled with a detailed experimental strategy to measuring indel formation at the target site, is outlined. This protocol outlines a foundational approach and workflow for investigations aimed at developing CRISPR/Cas9-based gene editing for human therapy. The conclusion of this work is that on-site mutagenesis takes place as a result of CRISPR/Cas9 activity during the process of point mutation repair. This work puts in place a standardized methodology to identify the degree of mutagenesis, which should be an important and critical aspect of any approach destined for clinical implementation.

This protocol outlines the workflow of a CRISPR/Cas9-based gene editing system for the repair of point mutations in mammalian cells. Here, we use a combinatorial approach to gene editing with a detailed follow-on experimental strategy for measuring indel formation at the target site&#8212;in essence, analyzing onsite mutagenesis.

CRISPR/Cas9 和 SsODN 在人细胞中催化点突变修复功能的标准方法研究

Combinatorial gene editing using CRISPR/Cas9 and single-stranded oligonucleotides is an effective strategy for the correction of single-base point ...

Microinjection of CRISPR/Cas9 Protein into Channel Catfish, Ictalurus punctatus, Embryos for Gene Editing

The complete genome of the channel catfish, Ictalurus punctatus, has been sequenced, leading to greater opportunities for studying channel catfish gene function. Gene knockout has been used to study these gene functions in vivo. The clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) system is a powerful tool used to edit genomic DNA sequences to alter gene function. While the traditional approach has been to introduce CRISPR/Cas9 mRNA into the single cell embryos through microinjection, this can be a slow and inefficient process in catfish. Here, a detailed protocol for microinjection of channel catfish embryos with CRISPR/Cas9 protein is described. Briefly, eggs and sperm were collected and then artificial fertilization performed. Fertilized eggs were transferred to a Petri dish containing Holtfreter's solution. Injection volume was calibrated and then guide RNAs/Cas9 targeting the toll/interleukin 1 receptor domain-containing adapter molecule (TICAM 1) gene and rhamnose binding lectin (RBL) gene were microinjected into the yolk of one-cell embryos. The gene knockout was successful as indels were confirmed by DNA sequencing. The predicted protein sequence alterations due to these mutations included frameshift and truncated protein due to premature stop codons.

Microinjection of CRISPR/Cas9 Protein into Channel Catfish, Ictalurus punctatus, Embryos for Gene Editing

A simple and efficient microinjection protocol for gene editing in channel catfish embryos using the CRISPR/Cas9 system is presented. In this protocol, guide RNAs and Cas9 protein were microinjected into the yolk of one-cell embryos. This protocol has been validated by knocking out two channel catfish immune-related genes.

CRISPR/Cas9 蛋白注射到沟鲶、鮰松毛虫、基因编辑的胚胎

The complete genome of the channel catfish, Ictalurus punctatus, has been sequenced, leading to greater opportunities for studying channel catfish gene ...

CRISPR/Cas9-mediated Targeted Integration In Vivo Using a Homology-mediated End Joining-based Strategy

As a promising genome editing platform, the CRISPR/Cas9 system has great potential for efficient genetic manipulation, especially for targeted integration of transgenes. However, due to the low efficiency of homologous recombination (HR) and various indel mutations of non-homologous end joining (NHEJ)-based strategies in non-dividing cells, in vivo genome editing remains a great challenge. Here, we describe a homology-mediated end joining (HMEJ)-based CRISPR/Cas9 system for efficient in vivo precise targeted integration. In this system, the targeted genome and the donor vector containing homology arms (~800 bp) flanked by single guide RNA (sgRNA) target sequences are cleaved by CRISPR/Cas9. This HMEJ-based strategy achieves efficient transgene integration in mouse zygotes, as well as in hepatocytes in vivo. Moreover, a HMEJ-based strategy offers an efficient approach for correction of fumarylacetoacetate hydrolase (Fah) mutation in the hepatocytes and rescues Fah-deficiency induced liver failure mice. Taken together, focusing on targeted integration, this HMEJ-based strategy provides a promising tool for a variety of applications, including generation of genetically modified animal models and targeted gene therapies.

CRISPR/Cas9-mediated Targeted Integration In Vivo Using a Homology-mediated End Joining-based Strategy

The clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) system provides a promising tool for genetic engineering, and opens up the possibility of targeted integration of transgenes. We describe a homology-mediated end joining (HMEJ)-based strategy for efficient DNA targeted integration in vivo and targeted gene therapies using CRISPR/Cas9.

CRISPR/Cas9-mediated 目标集成在体内使用基于同源介导的端接连接策略

As a promising genome editing platform, the CRISPR/Cas9 system has great potential for efficient genetic manipulation, especially for targeted integration ...

A Protocol for the Production of Integrase-deficient Lentiviral Vectors for CRISPR/Cas9-mediated Gene Knockout in Dividing Cells

Lentiviral vectors are an ideal choice for delivering gene-editing components to cells due to their capacity for stably transducing a broad range of cells and mediating high levels of gene expression. However, their ability to integrate into the host cell genome enhances the risk of insertional mutagenicity and thus raises safety concerns and limits their usage in clinical settings. Further, the persistent expression of gene-editing components delivered by these integration-competent lentiviral vectors (ICLVs) increases the probability of promiscuous gene targeting. As an alternative, a new generation of integrase-deficient lentiviral vectors (IDLVs) has been developed that addresses many of these concerns. Here the production protocol of a new and improved IDLV platform for CRISPR-mediated gene editing and list the steps involved in the purification and concentration of such vectors is described and their transduction and gene-editing efficiency using HEK-293T cells was demonstrated. This protocol is easily scalable and can be used to generate high titer IDLVs that are capable of transducing cells in vitro and in vivo. Moreover, this protocol can be easily adapted for the production of ICLVs.

We describe the production strategy of integrase-deficient lentiviral vectors (IDLVs) as vehicles for delivering CRISPR/Cas9 to cells. With an ability to mediate quick and robust gene editing in cells, IDLVs present a safer and equally effective vector platform for gene delivery compared to integrase-competent vectors.

整合酶缺陷慢病毒载体载体的制备及其在细胞 CRISPR/Cas9-mediated 基因敲除中的表达

Lentiviral vectors are an ideal choice for delivering gene-editing components to cells due to their capacity for stably transducing a broad range of cells ...

Efficient Production and Identification of CRISPR/Cas9-generated Gene Knockouts in the Model System Danio rerio

Characterization of the clustered, regularly interspaced, short, palindromic repeat (CRISPR) system of Streptococcus pyogenes has enabled the development of a customizable platform to rapidly generate gene modifications in a wide variety of organisms, including zebrafish. CRISPR-based genome editing uses a single guide RNA (sgRNA) to target a CRISPR-associated (Cas) endonuclease to a genomic DNA (gDNA) target of interest, where the Cas endonuclease generates a double-strand break (DSB). Repair of DSBs by error-prone mechanisms lead to insertions and/or deletions (indels). This can cause frameshift mutations that often introduce a premature stop codon within the coding sequence, thus creating a protein-null allele. CRISPR-based genome engineering requires only a few molecular components and is easily introduced into zebrafish embryos by microinjection. This protocol describes the methods used to generate CRISPR reagents for zebrafish microinjection and to identify fish exhibiting germline transmission of CRISPR-modified genes. These methods include in vitro transcription of sgRNAs, microinjection of CRISPR reagents, identification of indels induced at the target site using a PCR-based method called a heteroduplex mobility assay (HMA), and characterization of the indels using both a low throughput and a powerful next-generation sequencing (NGS)-based approach that can analyze multiple PCR products collected from heterozygous fish. This protocol is streamlined to minimize both the number of fish required and the types of equipment needed to perform the analyses. Furthermore, this protocol is designed to be amenable for use by laboratory personal of all levels of experience including undergraduates, enabling this powerful tool to be economically employed by any research group interested in performing CRISPR-based genomic modification in zebrafish.

Efficient Production and Identification of CRISPR/Cas9-generated Gene Knockouts in the Model System Danio rerio

Targeted genome editing in the model system Danio rerio (zebrafish) has been greatly facilitated by the emergence of CRISPR-based approaches. Herein, we describe a streamlined, robust protocol for generation and identification of CRISPR-derived nonsense alleles that incorporates the heteroduplex mobility assay and identification of mutations using next-generation sequencing.

斑马斑马模型系统中 CRISPR/Cas9-generated 基因挖空的高效生产与鉴定

Characterization of the clustered, regularly interspaced, short, palindromic repeat (CRISPR) system of Streptococcus pyogenes has enabled the development ...

Highly Efficient Gene Disruption of Murine and Human Hematopoietic Progenitor Cells by CRISPR/Cas9

Advances in the hematopoietic stem cell (HSCs) field have been aided by methods to genetically engineer primary progenitor cells as well as animal models. Complete gene ablation in HSCs required the generation of knockout mice from which HSCs could be isolated, and gene ablation in primary human HSCs was not possible. Viral transduction could be used for knock-down approaches, but these suffered from variable efficacy. In general, genetic manipulation of human and mouse hematopoietic cells was hampered by low efficiencies and extensive time and cost commitments. Recently, CRISPR/Cas9 has dramatically expanded the ability to engineer the DNA of mammalian cells. However, the application of CRISPR/Cas9 to hematopoietic cells has been challenging, mainly due to their low transfection efficiencies, the toxicity of plasmid-based approaches and the slow turnaround time of virus-based protocols.
A rapid method to perform CRISPR/Cas9-mediated gene editing in murine and human hematopoietic stem and progenitor cells with knockout efficiencies of up to 90% is provided in this article. This approach utilizes a ribonucleoprotein (RNP) delivery strategy with a streamlined three-day workflow. The use of Cas9-sgRNA RNP allows for a hit-and-run approach, introducing no exogenous DNA sequences in the genome of edited cells and reducing off-target effects. The RNP-based method is fast and straightforward: it does not require cloning of sgRNAs, virus preparation or specific sgRNA chemical modification. With this protocol, scientists should be able to successfully generate knockouts of a gene of interest in primary hematopoietic cells within a week, including downtimes for oligonucleotide synthesis. This approach will allow a much broader group of users to adapt this protocol for their needs.

A protocol for fast CRISPR/Cas9-mediated gene disruption in mouse and human primary hematopoietic cells is described in this article. Cas9-sgRNA ribonucleoproteins are introduced via electroporation with sgRNAs generated through in vitro transcription and commercial Cas9. High editing efficiencies are achieved with limited time and financial cost.

CRISPR/Cas9 对小鼠和人造血祖细胞的高效基因破坏

Advances in the hematopoietic stem cell (HSCs) field have been aided by methods to genetically engineer primary progenitor cells as well as animal models. ...

CRISPR/Cas9 Gene Editing to Make Conditional Mutants of Human Malaria Parasite P. falciparum

Malaria is a significant cause of morbidity and mortality worldwide. This disease, which primarily affects those living in tropical and subtropical regions, is caused by infection with Plasmodium parasites. The development of more effective drugs to combat malaria can be accelerated by improving our understanding of the biology of this complex parasite. Genetic manipulation of these parasites is key to understanding their biology; however, historically the genome of P. falciparum has been difficult to manipulate. Recently, CRISPR/Cas9 genome editing has been utilized in malaria parasites, allowing for easier protein tagging, generation of conditional protein knockdowns, and deletion of genes. CRISPR/Cas9 genome editing has proven to be a powerful tool for advancing the field of malaria research. Here, we describe a CRISPR/Cas9 method for generating glmS-based conditional knockdown mutants in P. falciparum. This method is highly adaptable to other types of genetic manipulations, including protein tagging and gene knockouts.

CRISPR/Cas9 Gene Editing to Make Conditional Mutants of Human Malaria Parasite P. falciparum

We describe a method for generating glmS-based conditional knockdown mutants in Plasmodium falciparum using CRISPR/Cas9 genome editing.

CRISPR/Cas9 基因编辑制作人类疟疾寄生虫的条件突变体

Malaria is a significant cause of morbidity and mortality worldwide. This disease, which primarily affects those living in tropical and subtropical ...