Clustered regularly interspaced short palindromic repeats (CRISPR) in conjunction with CRISPR-associated proteins (Cas) can be employed to introduce double stand breaks into mammalian genomes at user-defined loci. The endonuclease activity of the Cas complex can be targeted to a specific genomic region using a single guide RNA (sgRNA). We developed a ligation-independent cloning (LIC) assembly method for efficient and bias-free generation of large sgRNA libraries. Using this system, we performed an iterative shotgun cloning approach to generate an arrayed sgRNA library that targets one critical exon of almost every protein-coding human gene. An orthogonal mixing and deconvolution approach was used to obtain 19,506 unique sequence-validated sgRNAs (91.4% coverage). As tested in HEK 293T cells, constructs of this library have a median genome editing activity of 54.6% and employing sgRNAs of this library to generate knockout cells was successful for 19 out of 19 genes tested.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4597219 | PMC |
http://dx.doi.org/10.1038/srep14987 | DOI Listing |
Int J Mol Sci
November 2024
Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology Russian Academy of Sciences, 119334 Moscow, Russia.
Virus-like particles (VLPs) are an attractive vehicle for the delivery of Cas nuclease and guide RNA ribonucleoprotein complexes (RNPs). Most VLPs are produced by packaging SpCas9 and its sgRNA, which is expressed from the RNA polymerase III (Pol III)-transcribed U6 promoter. VLPs assemble in the cytoplasm, but U6-driven sgRNA is localized in the nucleus, which hinders the efficient formation and packaging of RNPs into VLPs.
View Article and Find Full Text PDFNat Biomed Eng
January 2025
Institute of Neuropathology, University of Zurich, Zurich, Switzerland.
Arrayed CRISPR libraries extend the scope of gene-perturbation screens to non-selectable cell phenotypes. However, library generation requires assembling thousands of vectors expressing single-guide RNAs (sgRNAs). Here, by leveraging massively parallel plasmid-cloning methodology, we show that arrayed libraries can be constructed for the genome-wide ablation (19,936 plasmids) of human protein-coding genes and for their activation and epigenetic silencing (22,442 plasmids), with each plasmid encoding an array of four non-overlapping sgRNAs designed to tolerate most human DNA polymorphisms.
View Article and Find Full Text PDFSTAR Protoc
December 2024
School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; Shanghai Clinical Research and Trial Center, Shanghai 201210, China. Electronic address:
Murine trophoblast organoids present a more balanced array of trophoblast subtypes, rendering them a suitable platform for CRISPR-Cas9-based screening. Here, we present a protocol for the derivation and culture of murine trophoblast organoids from trophoblast stem cells or placentae. We describe steps for establishing and differentiating murine trophoblast organoids, the characterization of trophoblast organoids in both conditions, the generation of focused single guide RNA (sgRNA) libraries, and the subsequent screening using those libraries in murine trophoblast organoids.
View Article and Find Full Text PDFPlant Methods
September 2024
Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
CRISPR/Cas9-mediated gene editing requires high efficiency to be routinely implemented, especially in species which are laborious and slow to transform. This requirement intensifies further when targeting multiple genes simultaneously, which is required for genetic screening or more complex genome engineering. Species in the Citrus genus fall into this category.
View Article and Find Full Text PDFAdv Healthc Mater
November 2024
Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, P. R. China.
Dendritic cells (DCs) are critical regulators of T cell immunity, with immense therapeutic potential against tumors and autoimmune diseases. Efficient gene editing in DCs is crucial for understanding their regulatory mechanisms and maximizing their therapeutic efficacy. However, DCs are notoriously difficult to transfect, posing a major bottleneck for conventional DNA and RNA-based editing approaches.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!