Your browser does not allow saving data (e.g. private mode): bookmarks will be lost when the tab closes.
Search PubMed
Keywords, author, journal, years — results from PubMed, abstracts with Russian translation, bookmarks in your browser.
Found: 26 179
Page 891 of 1000-
Advances in genome editing for improved animal breeding: A review.
Since centuries, the traits for production and disease resistance are being targeted while improving the genetic merit of domestic animals, using conventional breeding programs such as inbreeding, outbreeding, or introduction of marker-assisted selection. The arrival of new scientific concepts, such as cloning and genome engineering, has added a new and promising research dimension to the existing animal breeding programs. Development of genome editing technologies such as transcription activator-like effector nuclease, zinc finger nuclease, and clustered regularly interspaced short palindromic repeats systems begun a fresh era of genome editing, through which any change in the genome, including specific DNA sequence or indels, can be made with unprecedented precision and specificity. Furthermore, it offers an opportunity of intensification in the frequency of desirable alleles in an animal population through gene-edited individuals more rapidly than conventional breeding. The specific research is evolving swiftly with a focus on improvement of economically important animal species or their traits all of which form an important subject of this review. It also discusses the hurdles to commercialization of these techniques despite several patent applications owing to the ambiguous legal status of genome-editing methods on account of their disputed classification. Nonetheless, barring ethical concerns gene-editing entailing economically important genes offers a tremendous potential for breeding animals with desirable traits.
-
Heterologous Expression of Candida antarctica Lipase B in Aspergillus niger Using CRISPR/Cas9-mediated Multi-Gene Editing.
Aspergillus niger, a filamentous fungus, is known as a cell factory due to its ability to produce large amounts of organic acids and industrial enzymes. Lipase B from Candida antarctica (CALB) is one of the most widely used lipases in industrial applications, including oil processing, papermaking, food, pharmaceuticals, and personal care products. In this study, the CRISPR/Cas9 technique was employed to knock out the pyrG and kusA genes in A. niger. The CALB gene was integrated into the high-production protein gene loci, such as glaA and amyA, to construct a multi-copy CALB production engineered strain. Additionally, the pepA, aglU, and bglA genes were deleted, which minimized the background level of secreted proteins in A. niger and increased the production of CALB. After two rounds of gene editing, the A. niger with multi-copy CALB was created, and the engineered A. niger CCTCC 206047.09 with high CALB yield was isolated. After 120 h of liquid fermentation, the lipase activity reached 17.84 U/mL and the protein yield reached 10.21 mg/mL. In summary, an engineered A. niger strain with high lipase activity was successfully isolated by employing a CRISPR/Cas9 system to integrate CALB into high-expression loci, while simultaneously knocking out the host's highly expressed protein genes. These results provide an effective strategy for the high expression of both heterologous and homologous enzymes in A. niger.
-
Direct genome editing of patient-derived xenografts using CRISPR-Cas9 enables rapid in vivo functional genomics.
Patient-derived xenografts are high fidelity in vivo tumor models that accurately reflect many key aspects of human cancer. In contrast to either cancer cell lines or genetically engineered mouse models, the utility of PDXs has been limited by the inability to perform targeted genome editing of these tumors. To address this limitation, we have developed methods for CRISPR-Cas9 editing of PDXs using a tightly regulated, inducible Cas9 vector that does not require in vitro culture for selection of transduced cells. We demonstrate the utility of this platform in PDXs (1) to analyze genetic dependencies by targeted gene disruption and (2) to analyze mechanisms of acquired drug resistance by site-specific gene editing using templated homology-directed repair. This flexible system has broad application to other explant models and substantially augments the utility of PDXs as genetically programmable models of human cancer.
-
Research note: A novel double-gene deleted vaccine against hypervirulent MDV variant generated by CRISPR/Cas9-based gene editing.
Marek's disease (MD), an important avian immunosuppressive and neoplastic diseases, has resulted in huge economic losses for the poultry industry worldwide. Over the past 50 years, the long-term prevalence of this disease and the growing immune pressure of MD vaccination have triggered persistently increased virulence. The emerging hypervirulent variant of MDV (HV-MDV) overcomes the protection conferred by commercial vaccines, highlighting the urgent need to develop novel, highly efficient MD vaccines. To address this challenge, using CRISPR/Cas9-based gene editing, we generated a novel candidate vaccine, SQ01ΔmeqΔLAT, which features double deletions of both oncogene meq and LAT-clustered miRNAs. Comprehensive experiments confirmed the gene deletions, genetic stability and retention of the replication kinetics of the mutant, without revealing any adverse impact on the expression of essential viral genes. Further animal experiments showed no histopathological lesions or neoplastic changes in SQ01ΔmeqΔLAT-challenged birds, demonstrating favourable safety to chicken hosts. More importantly, the SQ01ΔmeqΔLAT vaccine achieved a high protection index (PI) of 88.9% against HV-MDV strain HNSQ01; this was an improvement compared to CVI988, which provided a PI value of only 70.6%. Our data provide an important basis for the development of highly efficient MD vaccines and shed new light on the design of herpesvirus vaccines, simultaneously targeting both viral protein-coding genes and non-coding RNAs.
-
Allele-specific genome targeting in the development of precision medicine.
The CRISPR-based genome editing holds immense potential to fix disease-causing mutations, however, must also handle substantial natural genetic variations between individuals. Previous studies have shown that mismatches between the single guide RNA (sgRNA) and genomic DNA may negatively impact sgRNA efficiencies and lead to imprecise specificity prediction. Hence, the genetic variations bring about a great challenge for designing platinum sgRNAs in large human populations. However, they also provide a promising entry for designing allele-specific sgRNAs for the treatment of each individual. The CRISPR system is rather specific, with the potential ability to discriminate between similar alleles, even based on a single nucleotide difference. Genetic variants contribute to the discrimination capabilities, once they generate a novel protospacer adjacent motif (PAM) site or locate in the seed region near an available PAM. Therefore, it can be leveraged to establish allele-specific targeting in numerous dominant human disorders, by selectively ablating the deleterious alleles. So far, allele-specific CRISPR has been increasingly implemented not only in treating dominantly inherited diseases, but also in research areas such as genome imprinting, haploinsufficiency, spatiotemporal loci imaging and immunocompatible manipulations. In this review, we will describe the working principles of allele-specific genome manipulations by virtue of expanding engineering tools of CRISPR. And then we will review new advances in the versatile applications of allele-specific CRISPR targeting in treating human genetic diseases, as well as in a series of other interesting research areas. Lastly, we will discuss their potential therapeutic utilities and considerations in the era of precision medicine.
-
Hematotherapy.
-
CRISPR-Cas guides the future of genetic engineering.
The diversity, modularity, and efficacy of CRISPR-Cas systems are driving a biotechnological revolution. RNA-guided Cas enzymes have been adopted as tools to manipulate the genomes of cultured cells, animals, and plants, accelerating the pace of fundamental research and enabling clinical and agricultural breakthroughs. We describe the basic mechanisms that set the CRISPR-Cas toolkit apart from other programmable gene-editing technologies, highlighting the diverse and naturally evolved systems now functionalized as biotechnologies. We discuss the rapidly evolving landscape of CRISPR-Cas applications, from gene editing to transcriptional regulation, imaging, and diagnostics. Continuing functional dissection and an expanding landscape of applications position CRISPR-Cas tools at the cutting edge of nucleic acid manipulation that is rewriting biology.
-
[Identify Myeloid Differentiation-Related MiRNAs Response to ATRA Induction by RNA Sequencing and CRISPR/Cas9 Gene Editing].
OBJECTIVE: To identify differentiation related miRNA and evaluate roles of miRNA during ATRA induced myeloid differentiation. METHODS: The small RNA sequencing was used to analyze differential expressed miRNAs in ATRA induced NB4 cells. Then the several up or down-regulated miRNA were selected as the research candidates. SgRNAs targeting the genome of each miRNA were designed and NB4 cells with inducible expression of Cas9 protein were generated. After transduced sgRNA into NB4/Cas9 cells, the mutation level by PCR and surveyor assay were evaluated. The cell differentiation level was investigated by surface CD11b expression via flow cytometry. RESULTS: A total of 410 mature miRNAs which expressed in NB4 cells were detected out after treated by ATRA, 74 miRNAs were up-regulated and 55 were down-regulated miRNAs with DNA cleavage generated by CRISPR/Cas9 was assayed directly by PCR or surveyor assay, quantitative PCR showed that the expression of miRNA was downregulated, which evaluated that gene edition successfully inhibitied the expression of mature miRNA. MiR-223 knockout showed the myeloid differentation of NB4 significantly inhibitied, while miRNA-155 knockout showed the myeloid differentation of NB4 cells significantly increased. CONCLUSION: CRISPR/Cas9 is a powerful tool for gene editing and can lead to miRNA knockout. Knockouts of miR-223 and miR-155 have shown a differentiation-related phenotype, and the potential mechanism is the integrative regulation of target genes.
-
The ethics of creating genetically modified children using genome editing.
PURPOSE OF REVIEW: To review the recent ethical, legal, and social issues surrounding human reproduction involving germline genome editing. RECENT FINDINGS: Genome editing techniques, such as CRISPR/Cas9, have facilitated genetic modification in human embryos. The most likely purpose of germline genome editing is the prevention of serious genetic disease in offspring. However, complex issues still remain, including irremediable risks to fetuses and future generations, the role of women, the availability of alternatives, long-term follow-up, health insurance coverage, misuse for human enhancement, and the potential effects on adoption. Further discussions, a broad consensus, and appropriate regulations are required before human germline genome editing is introduced into the global society. SUMMARY: Before germline genome editing is used for disease prevention, a broad consensus must be formed by carefully discussing its ethical, legal, and social issues.
-
CRISPR/Cas9 opens new horizon of crop improvement under stress condition.
Plants are exposed to a myriad of stresses, stemming from abiotic and biotic sources, significantly threatening agricultural productivity. The low crop yield, coupled with the global burden of population has resulted in the scarcity of quality food, exacerbating socio-economic issues like poverty, hunger, and malnutrition. Conventional breeding methods for the generation of stress-tolerant plants are time-consuming, limit genetic diversity, and are not sustainable for the consistent production of high-yielding crops. In recent years, the use of high-throughput, genome editing (GE) technique has revolutionized the crop-improvement paradigm, ushering greater prospects for agricultural progress. Among these tools, the Clustered regularly interspaced short palindromic repeat (CRISPR), and its associated nuclease protein Cas9, have appeared as a ground-breaking technology, allowing precise knockout (KO), upregulation, and downregulation of target gene expression. Apart from its high efficacy and speed, this programmable nuclease offers exceptional specificity with minimal off-target effects. Here in, we aim to review the latest findings on the application of the CRISPR/Cas9 genome editing tool for generating resilience in plants against environmental stresses.
PubMed returns only the first 10,000 results — refine the query to see the rest.