CRISPR Journal最新文献

Prime editing is a clustered regularly interspaced short palindromic repeats-based approach that enables the introduction of precise genetic modifications, including missense mutations, making it valuable for generating disease models. The comparative performance of novel prime editor (PE) variants in zebrafish remains largely unexplored. Here, we systematically evaluated the efficiency of five PEs-PE2, PE6b, PE6c, PEmax, and PE7-in zebrafish. We tested mRNA encoding for each of these PEs with prime editing guide RNAs (pegRNAs) designed to install five missense mutations. Efficient editing was achieved at four of the five sites with multiple PEs. Among these, PEmax emerged as the most efficient editor for introducing pure prime edits, with rates reaching 15.34%. We found that strategies proposed to block 3' degradation of pegRNAs (epegRNAs and addition of a La RNA binding motif to the PE) did not improve performance in our assays. Together, these findings establish PEmax as a robust tool to introduce missense mutations into zebrafish.

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 FaMYB9^CR-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, FaMYB9^CR-15 leaves also had large patches of wax. We identified 11,402 differentially expressed genes, divided into four clusters, between WT and FaMYB9^CR-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, FaMYB9^CR-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.

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.

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.

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.

Genome engineering methods can be utilized to perform complex genetic manipulations in living cells with remarkable efficiency and precision. Given the transformative potential of these enabling technologies, their applications are steadily expanding into most biology and biomedical fields where they play a central role in many experimental frameworks. For these reasons, in order to effectively prepare future generations of biologists and bioengineers for successful careers, there is a high need to incorporate courses teaching genome editing fundamentals into existing curricula. To accomplish this objective, lecture-based courses are rapidly integrating genome editing concepts; however, there are few laboratory courses that teach the practical skills needed to successfully perform genome editing experiments. Here, we describe the development and implementation of a semester-long laboratory course that teaches students not only the techniques needed to perform gene knockout, gene activation, gene repression, and base editing in mammalian cells but also prepares them to design and troubleshoot experiments, write scientific manuscripts, as well as prepare and deliver scientific presentations. Course evaluations demonstrate that this class effectively equips students with the knowledge and hands-on experience needed to succeed in careers related to genome engineering, cell and tissue engineering, and, more broadly, biology.

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.

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.

Science Gallery Bengaluru was established to serve as a two-way bridge between the public and new and old research. This work is furthered through public engagement in the form of year-long living exhibitions, a public laboratory complex with five experimental spaces, and a mentorship initiative for young adults. There is a strong conversation about professions in science and engineering in the Indian public domain, but its cultural equivalent is less developed. In this context, ideas and topics for exploration at the Gallery are chosen not for novelty with which the public is to be familiarized, but for their already robust presence in public discourse in order to explore their complexity through research in the human, social, and natural sciences, with a view to enabling visitors to make more informed choices in everyday life.