搜索结果：The CRISPR journal

Posterior capsular opacification (PCO) is the most common complication following cataract surgery and a significant cause of vision impairment. PCO arises from the proliferation, migration, and epithelial-mesenchymal transition (EMT) of residual lens epithelial cells (LECs), driven by an activated mTOR signalling pathway. Previous research has demonstrated that inhibiting mTOR activity effectively reduces LEC proliferation and EMT in rabbit models. However, achieving sustained mTOR inhibition remains a challenge. In this study, we encapsulated the CRISPR/Cas9 system targeting mTOR into chitosan nanoparticles (Chi-gRNA) with an average size of 135 nm. These nanoparticles exhibited resistance to DNase I digestion. To prolong release duration, we incorporated these Chi-gRNA nanoparticles onto the surface of intraocular lenses (IOLs) via layer-by-layer (LbL) assembly. The LbL coatings consisted of alternating layers of positively charged polyethyleneimine (PEI) and negatively charged heparin, interspersed with Chi-gRNA nanoparticles over five consecutive cycles. Spectral analysis confirmed the successful integration and coating of nanoparticles, with characteristic peaks validating the electrostatic assembly of the layers. In vitro assays demonstrated that Chi-gRNA-coated IOLs significantly inhibited the proliferation, migration, and adhesion of human lens epithelial cells (hLECs). These findings highlight the potential of LbL-coated IOLs to deliver CRISPR/Cas9 system-targeting mTOR nanoparticles as a novel and effective strategy to prevent PCO in patients undergoing cataract surgery. This approach offers a promising avenue for the long-term management of this prevalent postoperative complication.

On May 12, 2025, the US Court of Appeals for the Federal Circuit issued its second decision in the long-running CRISPR patent dispute between the Regents of the University of California and related institutions (CVC) and the Broad Institute. This Perspective recounts the principal dispute to date, reviews the Federal Circuit's recent opinion, and provides a critique of its analysis. In particular, this Perspective highlights how the decision is self-contradictory and in tension with patent law's conception doctrine-when an inventor has formed a "definite and permanent" idea of an invention in the mind or whether the invention was little more than a "bare hope" of a result. This Perspective briefly concludes with the implications of this recent decision and where the underlying dispute is likely headed.

CRISPR activation (CRISPRa) offers a powerful approach to upregulate endogenous genes; yet, existing systems in plants can be complex or difficult to integrate with CRISPR interference (CRISPRi). Here, we present a streamlined and flexible CRISPRa platform that enables robust gene activation. Using a dual-luciferase reporter, we benchmarked a range of guide RNA scaffolds, effector proteins, and promoters. We developed a novel single-guide RNA (sgRNA) architecture, harboring two MS2 aptamers inserted into the tetraloop and driven by a composite Pol II/Pol III promoter, as the most efficient configuration. This scaffold outperformed gR2.0- and SunTag-based constructs, reaching up to 100-fold activation of a minimal 35S promoter and up to 215-fold induction of three endogenous rice genes in protoplast assays. In contrast, scaffold RNAs (scRNAs) with aptamers at the 3' end or in excessive copy numbers were ineffective. Exploratory AlphaFold modeling supports a possible role for aptamer positioning and MCP-VP64 dimerization, although this remains a working hypothesis. This modular design enables tunable gene regulation in rice protoplasts and provides a practical platform for high-throughput screening and synthetic gene circuit prototyping in plants. Given that scRNA geometry and promoter architecture are universal features of CRISPR-based transcriptional modulation, the system is expected to be broadly portable across species. While the architecture is intended to be compatible with CRISPRi, future studies will be needed to establish its practical use in combined CRISPRa/i settings.

In November 2018, Chinese biophysicist He Jiankui stunned the world by announcing that he had created the first genetically-modified babies. Is he a rogue scientist? What are the socio-cultural contexts that motivated him to commit an act widely regarded as morally indefensible? What does it say about Chinese bioethics? How should we determine whether it can ever be justified to permanently alter the human gene pool? This article highlights the global institutional failures that enabled this unfortunate episode, including the prevailing international scientific culture and the persistent Western bias against scientific work originated in the Global South. It calls for systemic efforts-including regulatory reforms, increased transparency, public engagement, and international cooperation-to strengthen ethics governance both within nations and across borders. Finally, it advocates for decolonizing bioethics, advancing the sociology of bioethics, and fostering a cosmopolitan approach to ethics grounded in diversity, equity, inclusion, and our shared humanity.

Bacteria and archaea utilize CRISPR-Cas systems to defend against invading mobile genetic elements (MGEs) such as phages and plasmids. In turn, MGEs have evolved anti-CRISPR (Acr) proteins to counteract these defenses. While several type II-A Acrs have been identified in Streptococcus thermophilus (Sth) phages, a more comprehensive understanding of Acr diversity in Sth phages has yet to be explored. Guided by the genomic context of known Acrs, we systematically screened uncharacterized phage proteins and identified several novel Acrs that inhibit type I-E, type II-A or type III-A Sth CRISPR-Cas systems. These acr genes are clustered within a variable phage genomic region, indicating a hotspot for anti-defense activity. We also identified neighboring proteins with predicted enzymatic or structural domains that may modulate phage-host interactions through Acr-independent mechanisms. Together, our findings expand the known repertoire of Sth Acrs and highlight the phage variable region as a key reservoir of immune-modulating factors.

Modern gene synthesis platforms enable investigations of protein function and genome biology at an unprecedented scale. Yet, the proportion of error-free constructs in diverse gene libraries decreases with length due to the propagation of oligo synthesis errors. To rescue these error-free constructs, we developed Barcode-Assisted Retrieval CRISPR-Activated Targeting (BAR-CAT), an in vitro method that uses multiplexed dCas9-single-guide RNA (sgRNA) complexes to extract barcodes corresponding to error-free constructs. After a 15-min incubation and wash regimen, three low-bundance targets in a 300,000-member test library were enriched 600-fold, greatly reducing downstream requirements. When applied to a 384-gene DropSynth gene library, BAR-CAT enriched 12 targets up to 122-fold and revealed practical limits imposed by sgRNA competition and library complexity, which now guide ongoing protocol scaling. By eliminating laborious clone-by-clone validation and working directly on plasmid libraries, BAR-CAT provides a platform for recovering perfect synthetic genes, subsetting large libraries, and ultimately lowering the cost of functional genomics at scale.

The question of how law should regulate the manipulation of the human genome or germline is inflected by the interconnected, intersectional parrying among different systems of moral value. Contract law and constitutional law reflect two poles of interest: the transactional aspects of market valuation and the relational aspects of the web of life that acknowledge "pricelessness." In the decades from the initial decoding of the human genome in 2000 to the emergence of CRISPR technologies, powerful companies and powerful individuals now all but own the fate of our species and the health of our planet. The destructive effects of the realignments we are undergoing are still largely invisible (if not for long) and largely unresponsive to conventional checks.

Invasive species inflict major ecological, economic, and cultural harm worldwide, highlighting the urgent need for innovative control strategies. Genome editing offers exciting possibilities for targeted control methods for invasive species. Here, we demonstrate CRISPR-Cas9 genome editing in the cane toad (Rhinella marina), one of Australia's most notorious invasive species, by targeting the tyrosinase gene to produce albino phenotypes as visual markers for assessing editing efficiency. Microinjection of Cas9 protein and guide RNAs into one-cell zygotes resulted in 87.6% of mosaic larvae displaying nearly complete albinism, with 2.3% exhibiting complete albinism. For completely albino individuals, genomic analysis confirmed predominantly frameshift mutations or large deletions at the target site, with no wild-type alleles detected. Germline transmission rates reflected the extent of albinism in the mosaic adult, with maternal transmission approaching 100%. This first application of CRISPR-Cas9 in the Bufonidae family opens possibilities for exploring basic research questions and population control strategies.

CRISPR-Cas9 genome editing offers significant opportunities to improve livestock traits; however, its application in buffalo has been very limited, with no prior reports of live gene-edited animals. Here, we report the successful birth of a buffalo edited in the myostatin (MSTN) gene. To achieve this, five single-guide RNAs (sgRNAs) targeting the buffalo MSTN gene were designed and tested in skin-derived fibroblasts. Among these, sgRNA5 exhibited the highest editing efficiency, approaching ∼50%, as confirmed by T7 Endonuclease I assay, Tracking of Indels by Decomposition, and Inference of CRISPR Edits analyses. Single-cell cloning identified six edited fibroblast clonal populations, including one with a bi-allelic frameshift mutation predicted to severely truncate the MSTN protein. These bi-allelic clonal cells were subsequently used as nuclear donors to produce somatic cell nuclear transfer (SCNT) embryos, which were transferred into recipient buffaloes (n = 15). This effort established three pregnancies and resulted in the birth of one live MSTN knockout buffalo calf. Phenotypically, the calf displayed accelerated growth and increased muscle fiber number and size while maintaining normal meat composition. In conclusion, this study reports the world's first gene-edited buffalo generated through CRISPR-Cas9-mediated genome editing combined with SCNT. These findings provide a proof-of-concept for genome editing in buffalo and demonstrate that MSTN disruption can effectively enhance muscle growth and meat production traits.

The tuberous sclerosis complex (TSC)2 gene regulates the mammalian target of rapamycin (mTOR) pathway, impacting cell proliferation and growth. The loss-of-function mutations, especially in mesenchymal progenitors, drive the development multiple benign and malignant tumors. TSC2 mutations in certain cancer types, e.g., breast cancer, are also associated with poorer prognosis. The databases of TSC2-mutations report point mutations as the most prevalent. We aimed to test the feasibility of inducing point mutations in mesenchymal stem cells (MSCs), targeting the most frequent point mutations of the TSC2 gene, TSC2. c.1864 C>T (p.Arg622Trp), TSC2. c.1832 G>A (p.Arg611Glu), and TSC2. c.5024 C>T (p.Pro1675Leu) using two delivery methods for CRISPR-Cas9. We report a high editing efficiency of up to 85% inducing TSC2 point mutations in hMSCs using lipofectamine-based transfection. Overall, the high editing efficiency of some TSC2 mutations enables the induction and reversal of mutations in primary hMSCs without needing resource-consuming derivation of cell lines frequently distinct from their primary counterparts.

The advent of clustered regularly interspaced short palindromic repeats (CRISPR)-based technologies has revolutionized genome editing, with continued interest in expanding the CRISPR-associated proteins (Cas) toolbox with diverse, efficient, and specific effectors. CRISPR-Cas12a is a potent, programmable RNA-guided dual nickase, broadly used for genome editing. Here, we mined dairy cow microbial metagenomes for CRISPR-Cas systems, unraveling novel Cas12a enzymes. Using in silico pipelines, we characterized and predicted key drivers of CRISPR-Cas12a activity, encompassing guides and protospacer adjacent motifs for five systems. We next assessed their functional potential in cell-free transcription-translation assays with GFP-based fluorescence readouts. Lastly, we determined their genome editing potential in vivo in Escherichia coli by generating 1 kb knockouts. Unexpectedly, we observed natural sequence variation in the bridge-helix domain of the best-performing candidate and used mutagenesis to alter the activity of Cas12a orthologs, resulting in increased gene editing capabilities of a relatively inefficient candidate. This study illustrates the potential of underexplored metagenomic sequence diversity for the development and refinement of genome editing effectors.

Gene editing is more challenging in octoploids due to the presence of multiple copies of each gene. However, the ability to edit genes in these plants would allow editing in commercial varieties. Here, we delivered sequences targeting FaMYB9 into octoploid strawberry "Honeoye" and identified several gene-edited lines. Among them, the heterozygous gene-edited line FaMYB9CR-15 had curved and wrinkled leaves at 3 months, whereas leaves of 3-month-old wild-type (WT) strawberry seedlings were elliptical with a smooth surface. At that stage, FaMYB9CR-15 leaves also had large patches of wax. We identified 11,402 differentially expressed genes, divided into four clusters, between WT and FaMYB9CR-15 seedlings at 3 months. Notably, cluster 4 genes-related to nonhomologous end joining, microhomology-mediated end joining repairs, homologous recombination, nucleotide excision repair, and mismatch repair-were more highly expressed in the gene-edited line than in the WT. Surprisingly, by 6 months of age, FaMYB9CR-15 leaves had become smooth with small patches of wax, and expression levels of cluster 4 genes were significantly lower than at 3 months. Over the same period, the percentage of FaMYB9 loci harboring the mutant allele decreased from 70.2% to 43.7%. These findings lead us to conclude that there could be reversion of mutated sequences in octoploid strawberry, emphasizing the challenges of gene editing high-ploidy materials.

Conversations regarding genome editing are not simply about the transformative science involved. They touch upon fundamental moral questions concerning the human condition, indeed what it means to be human itself. The recent approval of a gene therapy for sickle cell disease encapsulates the relationship between scientific innovation and health care access and the relations of power and political economy that structure the world of biotech and biomedicine. Globally transformative biotechnologies must ethically situate themselves if they are not merely to reproduce longstanding historical and structural asymmetries. The time has come to embrace a cosmopolitan ethic that is attuned to the varied constitutionalisms through which debates about public good, healthy societies, and social compacts materialize around the world.

Incomplete repression of recombinant genes encoding toxic polypeptides can suppress cell growth even in the absence of a transcription inducer. To address this issue, we developed a CRISPR-Cas9-based genome editing approach that directly modifies the plasmid encoding the toxic peptide during Escherichia coli cultivation. The constructed plasmids contained a transcription terminator between the promoter and coding region, preventing full gene expression through abortive transcription. Upon CRISPR-Cas9 activation, this region is excised, thus restoring the functional gene. To implement this approach, we modified widely used pET-series expression plasmids by adding extra terminators in the 5'-untranslated region of the recombinant gene. Four antimicrobial peptides with strong bactericidal properties served as toxic gene products, while green fluorescent protein was used to assess the efficiency of expression repression. As a result, we developed an expression system with strong repression, which is activated by CRISPR-Cas9-mediated excision of a DNA fragment from the plasmids.

The cell and gene therapy/gene editing industry sits at the intersection of scientific research, technology development, regulation, ethics, and society. Hence, the biotechnology industry has a role in ensuring the inclusion of ethical considerations, diverse stakeholders, and assessments of medical progress, necessity, and realistic timelines for technological feasibility. The Alliance for Regenerative Medicine has sought to facilitate this role, fostering continued discussions of the scientific, ethical, and governance difficulties surrounding heritable human genome editing (HHGE), particularly in light of enormous advances in somatic gene therapies. The need for HHGE to address rare diseases is significantly diminished by the development of alternative approaches. Thoughtful deliberation about HHGE that takes into account the expertise and experience of the biotechnology industry is essential-as are guardrails to prevent unwarranted and irresponsible approaches to HHGE.

How should we govern our increasing power to intervene in the processes of life? Genome editing, especially of the human germline, has brought this question to the forefront of global debate. We must seek to rectify shortcomings of earlier deliberative approaches by setting aside a science-and-technology first approach; expanding the range of questions for deliberation; revisiting the distribution of innovation's benefits and risks; and reimagining the limits of research. This Perspective from the Organizing Committee of the 2025 Global Observatory for Genome Editing International Summit calls for a new social compact, recognizing and rendering accountable the constitutive role of science and technology in shaping the meaning of human life in the 21st century.

Recently, a new family of CRISPR-Cas12 endonucleases from an unexplored phylum of bacteria, Armatimonadota, was discovered. Named Cas12l, they are compact (800-900 aa), recognize a 5' C-rich protospacer adjacent motif, and present an N-terminal domain that stretches from the beginning to the end of the ribonucleoprotein-bound DNA target site, effectively locking it in place. Here, structure-guided rational design supplemented with AI-based large protein language model predictions was used to improve rates of DNA target cleavage of a family member, Asp2Cas12l. Compared to the wild-type, engineered variants exhibited an approximately 10-fold increase in double-strand break (DSB) editing efficiency in human cells with less target-to-target variation. Moreover, frequencies of editing were comparable to those of SpCas9 at overlapping target sites, and their DSBs efficiently corrected by homology-directed repair (39-56% of editing outcomes). Altogether, this study extends our understanding of CRISPR-Cas12 protein engineering and offers a potent new alternative for DSB-mediated genome editing in human cells.

CRISPR-based gene drives represent a powerful new technology for limiting disease transmission and controlling invasive populations. These systems rely on homology-directed repair (HDR) to "drive" a genetic element through a population. However, mammals tend to favor non-homologous end joining (NHEJ), which generates mutations that halt further drive propagation. Here, we describe the experimental characterization of a putative target locus for a gene drive system targeting the haploinsufficient spermatogenesis gene Klhl10 in the laboratory mouse. Using a newly designed "coding sequence cassette," we introduce downstream guide RNAs within the gene, ensuring that sperm undergoing NHEJ are selectively removed from the population. As a proof of principle, we demonstrate that targeting Klhl10 with constitutively expressed LbCas12a results in strong selection against frameshift-containing sperm, validating the core purification mechanism required for this drive strategy. Unexpectedly, we also observed that female offspring lacked most frameshift mutations, suggesting a previously unrecognized role for Klhl10 in oogenesis or early embryonic development.

Hepatocyte transplantation (HTx) offers a safer, less invasive alternative to orthotopic liver transplantation for inherited metabolic liver diseases, especially in high-risk pediatric patients. Combining HTx with ex vivo gene editing is a promising autologous therapeutic strategy using the patient's cells. We investigated the feasibility of this approach by applying CRISPR-Cas9 gene knock-out to neonatal mouse hepatocytes and comparing their engraftment potential with that of mature adult cells in the Fah-/- mouse model of hereditary tyrosinemia type I (HT1). Electroporation-mediated gene editing did not significantly impair the ability of neonatal hepatocytes to engraft in vivo. Quantitative histological analysis revealed comparable liver repopulation levels between recipients of gene-edited neonatal cells and adult cells after hepatoxicity-mediated selection, providing a benchmark for electroporation-mediated gene editing in neonatal hepatocytes, and supporting the development of genetically corrected neonatal hepatocyte products as a crucial long-term or bridge-to-transplant therapeutic strategy for pediatric liver disease.