Браузер не даёт сохранять данные (например, приватный режим): закладки пропадут после закрытия вкладки.
Поиск статей PubMed
Ключевые слова, автор, журнал, годы — результаты из PubMed, аннотации с переводом на русский, закладки в браузере.
Найдено: 26 149
Страница 582 из 1000-
Protocol for scarless genome editing of human pluripotent stem cell based on orthogonal selective reporters.
Human pluripotent stem cells (hPSCs) hold great promise for applications in regenerative medicine and disease modeling. Here, we present a protocol for establishing edited hPSC cell lines utilizing visualized orthogonal selective reporters. We describe steps for constructing plasmids, carrying out cell culture and electroporation, as well as performing drug-fluorescent dual enrichment, clone screening, and cell line characterization. This protocol facilitates the achievement of single-base homozygous mutations and reporter knockins, offering a reliable approach for precision genome editing.
-
RNA-DNA hybrid binding domain broadens the editing window of base editors.
Adenine base editors (ABEs) and cytosine base editors (CBEs) are prominent tools for precise genome editing but are hindered by limited editing activity at positions proximal to the protospacer adjacent motif (PAM). This study investigates the potential of enhancing base editors editing activity by fusing them with RNA-DNA hybrid binding domains (RHBDs). Specifically, fusing ABE8e with the RHBD of Homo sapiens RNaseH1 (RHBD1) significantly increased A-to-G editing efficiency in the PAM-proximal region (A9-A15) by up to 3.5-fold, while reducing off-target cytosine editing. Additionally, RHBD1 is compatible with ABEmax, BE4max, and dual base editor (eA&C-BEmax), enhancing their editing activity at the PAM-proximal bases. Notably, RHBD1-fused BE4max led to a 3.1-fold improvement in C-to-T editing efficiency at PAM-proximal region (C9-C12). Furthermore, we demonstrated that RHBD1-fused ABE8e could effectively edit disease-related single nucleotide variations (SNVs) in human cells and validated its efficacy in adult mouse liver. These findings highlight the significance of the RHBD in expanding editing window and the applicability of base editors for gene therapy and disease modeling.
-
CRISPR/Cas9-Mediated In Vitro Mutagenesis in GC-Like B Cells.
The CRISPR/Cas9 technology has developed into a powerful tool for genome editing, both in terms of gene silencing and the insertion of precise mutations. However, the application of CRISPR/Cas9-mediated mutagenesis in primary immune cells, in particular in B cells, is still in its infancy because of the difficulty to deliver the CRISPR/Cas9 system into these cells. Here, we describe a new method to use CRISPR/Cas9 for manipulating genes in germinal center (GC)-like B cells in vitro. We isolated Cas9-expressing B cells from R26-Cas9iGFP/+ mice (expressing Cas9 constitutively from the Rosa26 locus) and mixed them with control B cells. Primary B cells were cultured on CD40L- and BAFF-expressing feeder cells and transduced with retroviral particles expressing the sgRNAs of interest. Using this system, we have achieved complete gene knockouts in up to 92% of activated B cells.
-
Systematic pegRNA design with PRIDICT2.0 and ePRIDICT for efficient prime editing.
Prime editing is a versatile genome editing technology that enables precise genetic modifications without inducing DNA double-strand breaks. Owing to numerous variables in the prime editing guide RNA (pegRNA) design, experimentally identifying the most efficient pegRNA for a specific locus and edit is laborious. Therefore, we have developed computational tools to streamline this process. Here we present a comprehensive protocol detailing how to use PRIDICT2.0 and ePRIDICT, machine-learning models that assess the influence of the pegRNA design and chromatin context on prime editing. PRIDICT2.0 is an ensemble of attention-based bidirectional recurrent neural networks that predicts pegRNA efficiencies for replacements, insertions or deletions in different cellular contexts. Compared with other pegRNA design tools, PRIDICT2.0 accommodates larger edits-up to 40 base pairs-across diverse edit types, also allowing the introduction of silent bystander edits that can enhance editing efficiency. ePRIDICT, a gradient-boosting algorithm, further accounts for the local chromatin environments and assesses how the genomic location of the target site affects prime editing rates. Both tools are available at www.pridict.it for individual predictions or can be installed locally for batch processing of multiple edits and target sites. The protocol provides step-by-step instructions on using PRIDICT2.0 and ePRIDICT, covering sequence input, prediction generation and interpretation. Web-based predictions take under a minute, while local installation and batch processing may take up to several hours, depending on the dataset size. By streamlining pegRNA selection and chromatin context analysis, these tools promote the adoption of prime editing in basic and translational research.
-
Programmed sequential cutting endows Cas9 versatile base substitution capability in plants.
-
Broad range plastid genome editing with monomeric TALE-linked cytosine and dual base editors.
-
Carboxylated nanodiamond-mediated CRISPR-Cas9 delivery of human retinoschisis mutation into human iPSCs and mouse retina.
Nanodiamonds (NDs) are considered to be relatively safe carbon nanomaterials used for the transmission of DNA, proteins and drugs. The feasibility of utilizing the NDs to deliver CRISPR-Cas9 system for gene editing has not been clearly studied. Therefore, in this study, we aimed to use NDs as the carriers of CRISPR-Cas9 components designed to introduce the mutation in RS1 gene associated with X-linked retinoschisis (XLRS). ND particles with a diameter of 3 nm were functionalized by carboxylation of the surface and covalently conjugated with fluorescent mCherry protein. Two linear DNA constructs were attached to the conjugated mCherry: one encoded Cas9 endonuclease and GFP reporter, another encoded sgRNA and contained insert of HDR template designed to introduce RS1 c.625C>T mutation. Such nanoparticles were successfully delivered and internalized by human iPSCs and mouse retinas, the efficiency of internalization was significantly improved by mixing with BSA. The delivery of ND particles led to introduction of RS1 c.625C>T mutation in both human iPSCs and mouse retinas. Rs1 gene editing in mouse retinas resulted in several pathological features typical for XLRS, such as aberrant photoreceptor structure. To conclude, our ND-based CRISPR-Cas9 delivery system can be utilized as a tool for creating in vitro and in vivo disease models of XLRS. STATEMENT OF SIGNIFICANCE: X-linked retinoschisis (XLRS) is a prevalent hereditary retinal disease, which is caused by mutations in RS1 gene, whose product is important for structural organization of the retina. The recent development of genome editing techniques such as CRISPR-Cas9 significantly improved the prospects for better understanding the pathology and development of treatment for this disease. Firstly, gene editing can allow development of appropriate in vitro and in vivo disease models; secondly, CRISPR-Cas9 can be applied for gene therapy by removing the disease-causative mutation in vivo. The major prerequisite for these approaches is to develop safe and efficient CRISPR-Cas9 delivery system. In this study, we tested specifically modified nanodiamonds for such a delivery system. We were able to introduce Rs1 mutation into the mouse retina and, importantly, observed several XLRS-specific effects.
-
Transgene-Free Genome Editing in Tomato and Potato Plants Using Agrobacterium-Mediated Delivery of a CRISPR/Cas9 Cytidine Base Editor.
Genome editing tools have rapidly been adopted by plant scientists for gene function discovery and crop improvement. The current technical challenge is to efficiently induce precise and predictable targeted point mutations valuable for crop breeding purposes. Cytidine base editors (CBEs) are CRISPR/Cas9 derived tools recently developed to direct a C-to-T base conversion. Stable genomic integration of CRISPR/Cas9 components through Agrobacterium-mediated transformation is the most widely used approach in dicotyledonous plants. However, elimination of foreign DNA may be difficult to achieve, especially in vegetatively propagated plants. In this study, we targeted the acetolactate synthase (ALS) gene in tomato and potato by a CBE using Agrobacterium-mediated transformation. We successfully and efficiently edited the targeted cytidine bases, leading to chlorsulfuron-resistant plants with precise base edition efficiency up to 71% in tomato. More importantly, we produced 12.9% and 10% edited but transgene-free plants in the first generation in tomato and potato, respectively. Such an approach is expected to decrease deleterious effects due to the random integration of transgene(s) into the host genome. Our successful approach opens up new perspectives for genome engineering by the co-edition of the ALS with other gene(s), leading to transgene-free plants harboring new traits of interest.
-
Precise epigenomic editing with a SunTag-based modular epigenetic toolkit.
Epigenetic regulation is a crucial factor controlling gene expression. Here, we report our CRISPR/dCas9-based modular epigenetic toolkit that enables gene-specific modulation of epigenetic architecture. By modifying the SunTag framework of dCas9 tagged with five GCN4 moieties, each epigenetic writer is bound to scFv and target-specific sgRNA, and this system is able to modify multiple epigenetic marks in a target-specific manner. We successfully demonstrated that this system is efficient in modifying individual histone post-translational modifications. We display its utility as a tool to understand the contributions of specific histone marks on gene expression by screening a large promoter region and identifying differential outcomes with high base-pair resolution. This epigenetic toolkit can be easily altered with a large variety of epigenetic effectors and is a useful tool for researchers to use in understanding gene-specific epigenetic changes and their relation to gene expression.
-
A Precise Genome Editing Method Reveals Insights into the Activity of Eukaryotic Promoters.
Despite the availability of whole-genome sequences for almost all model organisms, making faithful predictions of gene expression levels based solely on the corresponding promoter sequences remains a challenge. Plasmid-based approaches and methods involving selection markers are not ideal due to copy-number fluctuations and their disruptive nature. Here, we present a genome editing method using the CRISPR/Cas9 complex and elucidate insights into the activity of canonical promoters in live yeast cells. The method involves the introduction of a novel cut site into a specific genomic location, followed by the integration of an edited sequence into the same location in a scarless manner. Using this method to edit the GAL1 and GAL80 promoter sequences, we found that the relative positioning of promoter elements was critically important for setting promoter activity levels in single cells. The method can be extended to other organisms to decode genotype-phenotype relationships in various gene networks.
PubMed отдаёт не больше 10 000 первых результатов — уточните запрос, чтобы увидеть остальные.