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At least 19 recordsLinked to original sources

PubMed2026

Genetic Deletion of Cis-Regulatory Elements to Dissect the Function of the Non-coding Genome in human Preimplantation Models.

Cis-regulatory elements coordinate gene expression in a spatially and temporally controlled manner and contribute to the establishment of distinct cellular states during development. A substantial proportion of transcriptionally active cis-regulatory elements in primate embryos originated from ancient retroviral integrations into the germline. These endogenous retroviruses, also known as long terminal repeat retrotransposons, retain intrinsic regulatory activity and are often species-specific, making them strong candidates for regulating species-divergent aspects of embryonic development. Ethical and legal restrictions on human embryo research have historically limited direct investigation of gene regulation during human embryogenesis. Human naive pluripotent stem cells and three-dimensional stem cell-based blastocyst models provide alternative systems for studying early developmental processes. This protocol describes the CRISPR-Cas9-mediated deletion of endogenous retrovirus-derived cis-regulatory elements in human naive pluripotent stem cells. Preassembled Cas9 and single-guide RNA ribonucleoprotein complexes are delivered by nucleofection, followed by single-cell cloning, PCR-based genotyping, Sanger sequencing, expansion, cryopreservation, and genomic stability assessment of the edited lines. The resulting wild-type, heterozygous, and homozygous or hemizygous deletion clones provide a platform for investigating the contribution of individual endogenous retrovirus-derived elements to gene regulation in human preimplantation models. This method enables direct functional interrogation of species-specific non-coding regulatory sequences and supports the study of transcriptional mechanisms involved in early human development.

Humans↗

PubMed2026

Cross-target and cell-preferential CRISPR-Cas9 inhibition with carbohydrate-tagged oligonucleotides.

Precise control of clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) activity is important for limiting off-target effects and chromosomal rearrangements. Existing inhibitors, including anti-CRISPR proteins and spacer-targeting oligonucleotides, can be constrained by immunogenicity, target-sequence dependence, or delivery challenges. Here, we developed single-stranded DNA oligonucleotides that target conserved regions of the Streptococcus pyogenes Cas9 single-guide RNA (sgRNA) scaffold rather than the variable spacer. Screening identified single-stranded DNA 7 (ssDNA7), which targets stem-loop-1 and the adjacent linker and inhibits Cas9 activity across multiple tested spacer sequences and genomic loci without redesigning the inhibitor. Carbohydrate conjugation improved oligonucleotide stability and preferentially enhanced inhibitory activity in selected liver-derived or cancer cell models. Amplicon sequencing confirmed inhibition of endogenous editing in multiple cell models and normal liver-derived organoids, and supported cell-preferential inhibition in matched cell comparisons. These findings establish sgRNA-scaffold targeting as a strategy for cross-target inhibition of Cas9 and show that carbohydrate conjugation can tune its cellular activity.

CRISPR-Cas9↗

PubMed2026

Spatially guided in vivo single-cell functional genomics of postnatal heart.

Understanding how spatial organization and cell-cell interactions shape gene regulatory programs is central to decoding tissue development and function. The transition at birth, marked by increased circulatory demands and rapid tissue growth, requires precise spatiotemporal coordination of cardiac maturation. In this study, we generated a high-resolution spatial and temporal atlas of the postnatal mouse heart by integrating single-nucleus RNA sequencing with image-based spatial transcriptomics. This framework revealed dynamic cellular interactions, niche-specific signaling and transcriptional programs guiding cardiomyocyte maturation. To functionally test prioritized regulators in vivo and at scale, we developed PIP-seq (probe-based indel-detectable Perturb-seq), a high-throughput platform that detects single guide RNA identity, infers gene editing and profiles transcription from fixed nuclei. Applying PIP-seq to the developing postnatal heart, we identified 21 previously uncharacterized regulators of cardiomyocyte maturation, including genes essential for sarcomere assembly, metabolic reprogramming and electrophysiological transitions. Together, our findings define how microenvironmental signals and intrinsic gene programs cooperate to guide heart maturation and establish a broadly applicable framework for functional genomics in complex tissues.

Animals↗

PubMed2026

Towards efficient perturbation for the noncoding genome.

Deciphering the functionality of the noncoding genome, which includes important cis-regulatory elements (CREs) and transcribed noncoding RNA genes, remains technically challenging. Here, using massively parallel genetic screening, we systematically benchmark the performance of five representative loss-of-function perturbation tools, including single-guide RNA (gRNA) mediated SpCas9 cleavage or CRISPR interference, and paired gRNA (pgRNA) involved dual-SpCas9, Big Papi (paired SpCas9 and SaCas9) or dual-enAsCas12a fragment deletion methods, in decoding the roles of the noncoding genome. For targeting CREs such as enhancers, dual-SpCas9 outperforms other methods with superior efficiency in destroying functional genomic regions. For perturbing noncoding RNA genes, in addition to dual-SpCas9, other RNA-targeting methods such as RNA interference are recommended to discriminate transcript-dependent or -independent roles. A deep learning model, DeepDC, with an associated web server, is built to facilitate optimal dual-SpCas9 pgRNA design for efficiently deleting a genomic fragment. Together, our work provides practical guidance on selecting appropriate loss-of-function tools to resolve the functional complexity of the noncoding genome.

CRISPR-Cas Systems↗

PubMed2025

Leveraging protein language models for cross-variant CRISPR/Cas9 sgRNA activity prediction.

MOTIVATION: Accurate prediction of single-guide RNA (sgRNA) activity is crucial for optimizing the CRISPR/Cas9 gene-editing system, as it directly influences the efficiency and accuracy of genome modifications. However, existing prediction methods mainly rely on large-scale experimental data of a single Cas9 variant to construct Cas9 protein (variants)-specific sgRNA activity prediction models, which limits their generalization ability and prediction performance across different Cas9 protein (variants), as well as their scalability to the continuously discovered new variants. RESULTS: In this study, we proposed PLM-CRISPR, a novel deep learning-based model that leverages protein language models to capture Cas9 protein (variants) representations for cross-variant sgRNA activity prediction. PLM-CRISPR uses tailored feature extraction modules for both sgRNA and protein sequences, incorporating a cross-variant training strategy and a dynamic feature fusion mechanism to effectively model their interactions. Extensive experiments demonstrate that PLM-CRISPR outperforms existing methods across datasets spanning seven Cas9 protein (variants) in three real-world scenarios, demonstrating its superior performance in handling data-scarce situations, including cases with few or no samples for novel variants. Comparative analyses with traditional machine learning and deep learning models further confirm the effectiveness of PLM-CRISPR. Additionally, motif analysis reveals that PLM-CRISPR accurately identifies high-activity sgRNA sequence patterns across diverse Cas9 protein (variants). Overall, PLM-CRISPR provides a robust, scalable, and generalizable solution for sgRNA activity prediction across diverse Cas9 protein (variants). AVAILABILITY AND IMPLEMENTATION: The source code can be obtained from https://github.com/CSUBioGroup/PLM-CRISPR.

CRISPR-Cas Systems↗

PubMed2026

Protocol to identify genes required for cardiomyocyte development using Perturb-Seq.

While Perturb-Seq combines CRISPR-based screening with single-cell RNA sequencing (scRNA-seq), large-scale experiments are costly and its application during development is complicated by differentiation heterogeneity. Here, we present a protocol to identify genes required for cardiomyocyte development using Perturb-Seq. We describe steps for sgRNA (single guide RNA) library cloning and infection, cardiomyocyte differentiation, cell hashing, super loading, and scRNA-seq. We then detail procedures for sequencing, mapping, and data analysis. For complete details on the use and execution of this protocol, please refer to Sivakumar et al.1.

CRISPR↗

PubMed2026

Lipid-nanoparticle-mediated base editing of the trabecular meshwork rescues glaucoma in vivo.

Mutations in MYOC, the most common genetic cause of glaucoma, cause misfolded myocilin to accumulate in the endoplasmic reticulum (ER), leading to trabecular meshwork (TM) dysfunction, elevated intraocular pressure, and progressive vision loss. While gene editing offers curative potential, current delivery methods rely on viral vectors, which are limited by inflammation, off-target effects, and poor translatability. Here, we report a nonviral lipid nanoparticle (LNP) platform that enables selective in vivo delivery of mRNA encoding an adenine base editor and single guide RNA (LNP-ABE) to TM cells. A direct comparison of LNP-mCherry with lentiviral GFP revealed that LNPs outperform viral vectors, achieving markedly higher efficiency and greater selectivity for the TM without inducing ocular inflammation. In a Cre-inducible Tg.CreMYOCY437H glaucoma mouse model, LNP-Cre mRNA selectively induced mutant MYOC expression in the TM, faithfully recapitulating key disease features. A single administration of LNP-ABE achieved efficient on-target editing of mutant MYOC, reducing mutant myocilin protein by approximately 46%, decreasing aggregates, alleviating ER stress, and fully rescuing the glaucomatous phenotype in Tg.CreMYOCY437H mice. Importantly, no off-target editing or ocular toxicity was detected. These findings establish LNP-based mRNA delivery as a safe, efficient, and clinically translatable approach for TM-targeted genome editing with broad therapeutic potential in glaucoma.

Animals↗

PubMed2025

Cellular Inflammation-Induced Cleavage of Phosphorothioate DNA Locker Activates CRISPR/Cas9 Regulator for Gene Editing.

The CRISPR technology is a highly promising strategy for developing a versatile toolbox to engineer genetic circuits. However, achieving precise and specific control over the activity of the CRISPR/Cas9 system in response to intracellular processes remains a challenging endeavor. In this study, we present a cellular inflammation-induced activation of an engineered CRISPR/Cas9 regulator for gene regulation. A phosphorothioate (PS)-modified DNA sequence, referred as the "locker," is employed to deactivate single guide RNA (sgRNA), whose locker sequence complements the spacer region of sgRNA. In the presence of myeloperoxidase during cellular inflammation, a halogenation process is triggered, leading to the generation of HClO, specifically cleaving the PS site of locker and activating CRISPR/Cas9 for gene editing. The target GFP gene has been successfully edited, downregulating the GFP protein expression in HeLa cells. This study provides valuable insights into the CRISPR-based gene regulation through specific endogenous processes.

Humans↗

PubMed2025

Quantifying Protein-Nucleic Acid Interactions for Engineering Useful CRISPR-Cas9 Genome-Editing Variants.

Numerous high-specificity Cas9 variants have been engineered for precision genome editing. These variants typically harbor multiple mutations designed to alter the Cas9-single guide RNA (sgRNA)-DNA complex interactions for reduced off-target cleavage. By dissecting the contributions of individual mutations, we attempt to derive principles for designing high-specificity Cas9 variants. Here, we computationally modeled the specificity harnessing mutations of the widely used Cas9 isolated from Streptococcus pyogenes (SpCas9) and investigated their individual mutational effects. We quantified the mutational effects in terms of energy and contact changes by comparing the wild-type and mutant structures. We found that these mutations disrupt the protein-protein or protein-DNA contacts within the Cas9-sgRNA-DNA complex. We also identified additional impacted amino acid sites via energy changes that constitute the structural microenvironment encompassing the focal mutation, giving insights into how the mutations contribute to the high-specificity phenotype of SpCas9. Our method outlines a strategy to evaluate mutational effects that can facilitate rational design for Cas9 optimization.

Gene Editing↗

PubMed2026

Extracellular vesicles-mediated delivery of SpCas9 RNPs for therapeutic gene editing in Spinocerebellar Ataxia Type 3.

Spinocerebellar Ataxia Type 3 (SCA3) is a neurodegenerative dominantly-inherited disorder caused by an overexpansion of a CAG tract within the ATXN3 gene, conferring toxic properties to the ataxin-3 protein. Genome editing with CRISPR-Cas9 enzymes is a promising strategy to inactivate mutant ATXN3 alleles, however, in vivo delivery remains challenging. Extracellular vesicles (EVs) are promising delivery vehicles for Cas9 and single guide RNA (sgRNA) ribonucleoproteins that minimize genomic exposure to highly active endonucleases. In this study, we designed SpCas9 with a palmitoylation motif that enables SpCas9 and sgRNA enrichment into EVs. Introduction of a photocleavable linker - PhoCl - allowed the photo-inducible release of SpCas9 from the palmitoylation motif in EVs, increasing target engagement to ATXN3 in vitro. EVs loaded with SpCas9 ribonucleoproteins resulted in ATXN3 knockout in SCA3 patient-derived iPSCs and two SCA3 animal models. These findings highlight an innovative route for transient delivery of gene editing tools. This approach provides a promising therapeutic platform for the treatment of genetic diseases, including SCA3.

Humans↗

PubMed2026

Rational and computation-assisted engineering of a compact and efficient CRISPR-Cas12f genome editor.

The CRISPR-Cas12f system is an ultracompact genome-editing platform, yet only a few orthologs exhibit robust activity in mammalian cells. Here, we systematically screened 23 Cas12f orthologs and identified two active nucleases, PspCas12f1 and TcCas12f1, capable of genome editing in human cells. Single guide RNA (sgRNA) scaffold optimization enhanced the basal activity of PspCas12f1. To further improve its performance, we combined structure-guided rational design with protein language model-assisted filtering. Candidate mutations predicted by SaProt were further screened based on structural proximity to the DNA-binding interface and electrostatic compatibility. This integrative strategy identified Q100R and E293R, whose combination yielded the optimized variant enPspCas12f1. enPspCas12f1 achieved genome-editing efficiencies comparable to SpCas9 across multiple endogenous loci while maintaining high specificity. Collectively, our results demonstrate that integrating protein language model-assisted filtering with structure-guided rational design provides an effective strategy for engineering PspCas12f1 and may facilitate the optimization of additional compact CRISPR nucleases.

CRISPR-Cas12f↗

PubMed2025

Design of highly functional genome editors by modelling CRISPR-Cas sequences.

Gene editing has the potential to solve fundamental challenges in agriculture, biotechnology and human health. CRISPR-based gene editors derived from microorganisms, although powerful, often show notable functional tradeoffs when ported into non-native environments, such as human cells1. Artificial-intelligence-enabled design provides a powerful alternative with the potential to bypass evolutionary constraints and generate editors with optimal properties. Here, using large language models2 trained on biological diversity at scale, we demonstrate successful precision editing of the human genome with a programmable gene editor designed with artificial intelligence. To achieve this goal, we curated a dataset of more than 1 million CRISPR operons through systematic mining of 26 terabases of assembled genomes and metagenomes. We demonstrate the capacity of our models by generating 4.8× the number of protein clusters across CRISPR-Cas families found in nature and tailoring single-guide RNA sequences for Cas9-like effector proteins. Several of the generated gene editors show comparable or improved activity and specificity relative to SpCas9, the prototypical gene editing effector, while being 400 mutations away in sequence. Finally, we demonstrate that an artificial-intelligence-generated gene editor, denoted as OpenCRISPR-1, exhibits compatibility with base editing. We release OpenCRISPR-1 to facilitate broad, ethical use across research and commercial applications.

CRISPR-Cas Systems↗

PubMed2019

Targeted delivery of CRISPR interference system against Fabp4 to white adipocytes ameliorates obesity, inflammation, hepatic steatosis, and insulin resistance.

Obesity is an increasing pathophysiological problem in developed societies. Despite all major progress in understanding molecular mechanisms of obesity, currently available anti-obesity drugs have shown limited efficacy with severe side effects. CRISPR interference (CRISPRi) mechanism based on catalytically dead Cas9 (dCas9) and single guide RNA (sgRNA) was combined with a targeted nonviral gene delivery system to treat obesity and obesity-induced type 2 diabetes. A fusion peptide targeting a vascular and cellular marker of adipose tissue, prohibitin, was developed by conjugation of adipocyte targeting sequence (CKGGRAKDC) to 9-mer arginine (ATS-9R). (dCas9/sgFabp4) + ATS-9R oligoplexes showed effective condensation and selective delivery into mature adipocytes. Targeted delivery of the CRISPRi system against Fabp4 to white adipocytes by ATS-9R induced effective silencing of Fabp4, resulting in reduction of body weight and inflammation and restoration of hepatic steatosis in obese mice. This RNA-guided DNA recognition platform provides a simple and safe approach to regress and treat obesity and obesity-induced metabolic syndromes.

3T3 Cells↗

PubMed2025

In planta genome editing in citrus facilitated by co-expression of CRISPR/Cas and developmental regulators.

Recent advances in the field of genome editing offer a promising avenue for targeted trait improvements in fruit trees. However, the predominant method taken for genome editing in citrus (and other fruit trees) involves the time-consuming tissue culture approach, thereby prolonging the overall citrus breeding process and subjecting it to the drawbacks associated with somaclonal variation. In this study, we introduce an in planta approach for genome editing in soil-grown citrus plants via direct transformation of young seedlings. Our editing system, abbreviated here as IPGEC (in planta genome editing in citrus), is designed to transiently co-express three key gene groups in citrus tissue via Agrobacterium tumefaciens: (i) a genome-editing catalytic group, (ii) a shoot induction and regeneration group, and (iii) a T-DNA enhanced delivery group. This integrated system significantly improves de novo shoot induction and regeneration efficiency of edited tissue. By incorporating single-guides RNA's (sgRNA's) targeting the carotenoid biosynthetic gene PHYTOENE DESATURASE (CsPDS), the IPGEC system effectively produced mutated albino shoots, confirming its ability to generate homozygous/biallelic genome-edited plants. By using high throughput screening, we provide evidence that transgene-free genome-edited plants could be obtained following the IPGEC approach. Our findings further suggest that the efficiency of specific developmental regulators in inducing transformation and regeneration rates may be cultivar-specific and therefore needs to be optimized per cultivar. Finally, targeted breeding for specific trait improvements in already successful cultivars is likely to revolutionize fruit tree breeding and will pave the way for accelerating the development of high-quality citrus cultivars.

Citrus↗

PubMed2026

Virus-induced gene editing of stomatal regulators in Nicotiana benthamiana enables rapid functional genomics.

Virus-induced gene editing (VIGE) holds promise as a rapid and scalable approach for functional genomics in plants. Here, we apply a tobacco rattle virus (TRV)-based single-guide RNA (sgRNA) delivery system to target key regulators of stomatal development in Nicotiana benthamiana using transgenic Cas9-expressing lines. sgRNAs fused to a mobile RNA element and co-delivered with TRV enabled both somatic and heritable genome editing across orthologs of STOMAGEN, EPF2, YODA, and SPEECHLESS. Somatic editing frequencies reached up to 95%, and heritable tetra-allelic mutations were recovered in multiple target genes. Mutants exhibited significant, gene-specific changes in stomatal density, with corresponding effects on leaf temperature indicative of altered evaporative cooling. Additionally, sgRNAs fused to an AmCyan reporter enabled visualization of virus-infected tissues, allowing stomatal phenotyping in edited M0 sectors. This TRV-based platform facilitates functional assessment of genes influencing stomatal patterning and offers a powerful tool for dissecting gene function in a developmentally and physiologically relevant context.

Nicotiana↗

PubMed2026

GFER Represents a Target for Dual Disruption of Redox Homeostasis and Reactivation of the Immune Response in Pancreatic Adenocarcinoma.

UNLABELLED: Both metabolic dysregulation and the immunosuppressive tumor microenvironment of pancreatic ductal adenocarcinoma (PDAC) contribute to the recalcitrance of this lethal disease to treatment. Accordingly, we aimed to identify and characterize a target that elicits an anticancer response through both disrupting cancer cell redox homeostasis and increasing the immunogenicity of PDAC. First, mitochondrial metabolic dependencies in PDAC were identified by using a CRISPR-Cas9 screening system with a custom single-guide RNA library. Functional validation analyses revealed GFER, a mitochondrial FAD-dependent sulfhydryl oxidase, as an essential regulator of tumor growth. In vitro and in vivo methodologies demonstrated that GFER depletion perturbed redox homeostasis and stimulated tumor immunogenicity, including sensitization to immune checkpoint blockade. In patient-derived xenograft models of PDAC, the growth-inhibitory response induced by GFER depletion was mediated by an altered oxidative balance that released damaged mitochondrial DNA into the cytoplasm of tumor cells, leading to the activation of the cGAS-STING pathway and expression of type I IFNs. This effect was recapitulated in a mouse immunocompetent syngeneic PDAC model, in which GFER depletion suppressed tumor growth and promoted T-cell infiltration to enhance tumor-killing effects. Consequently, GFER depletion significantly increased the antitumor efficacy of immune checkpoint blockade. Overall, these findings identify GFER as a critical node for both mitochondrial redox homeostasis and immunomodulation in PDAC and reveal a therapeutic opportunity for sensitizing PDAC to immune checkpoint blockade. SIGNIFICANCE: GFER is essential for mitochondrial redox balance and suppressing tumor immunogenicity in pancreatic tumors, with the combination of GFER inhibition with immune checkpoint blockade resulting in a strong antitumor response.

Animals↗

PubMed2026

CRISPR Screen Identifies HDAC3 as a Novel Radiosensitizing Target in Small Cell Lung Cancer.

Small cell lung cancer (SCLC) is an aggressive malignancy, with most patients presenting with prognostically poor extensive-stage disease. Limited progress in standard care stresses the urgent need for novel therapies. Radiotherapy offers some survival benefit for selected patients with SCLC but could be enhanced with radiosensitizers. In this study, we identify HDAC3 as a novel radiosensitizing target in SCLC using a CRISPR knockout screen and demonstrate its efficacy and mechanism. SBC5 cells were transduced with a custom EpiDrug single-guide RNA library and treated with ionizing radiation (IR) to identify radiosensitizing genes. HDAC3 emerged as a candidate and was validated through genetic knockdown and pharmacologic inhibition (RGFP966) in multiple SCLC cell lines. Both approaches enhanced radiosensitivity, as shown by cell viability (dose modification factor10 = 1.14-1.69) and clonogenic assays (dose modification factor10 = 1.16-1.41). We assessed changes in chromatin accessibility by assay for transposase-accessible chromatin using sequencing and IR-induced DNA damage and repair using γH2AX foci detection, double-strand break (DSB) repair assays, and immunoblotting of repair proteins. HDAC3-deficient cells exhibited increased chromatin accessibility, greater IR-induced DSBs, and impaired repair capacity, resulting in persistent DNA damage. This repair defect sensitized cells to PARP inhibitors, for which combining RGFP966 with olaparib or talazoparib produced additive to synergistic effects. In SCLC xenograft models, HDAC3 knockdown or RGFP966, combined with IR, achieved significant tumor growth inhibition. Collectively, we identified HDAC3 as a novel radiosensitizing target in SCLC. Its functional loss increased the generation and persistence of IR-induced DNA DSBs, effectively sensitizing SCLC cell lines and xenografts to IR, providing a potential radiosensitization strategy to treat SCLC.

Humans↗

PubMed2025

Lentiviral CRISPRa/i in the adult prairie vole brain: modulating neuronal gene expression without DNA cleavage.

Prairie voles (Microtus ochrogaster) are a powerful model for studying the neurobiology of social bonding, yet tools for region- and cell type-specific gene regulation remain underdeveloped in this species. Here, we present a lentivirus-mediated CRISPR activation and interference (CRISPRa/i) platform for somatic gene modulation in the prairie vole brain. This system enables non-mutagenic, titratable regulation of gene expression in the adult brain without germline modification. Our dual-vector system includes one construct expressing dCas9-VPR (VP64-p65-Rta) referred to as CRISPRa or dCas9-KRAB-MeCP2 (Kruppel-associated box-methyl CpG binding protein 2), referred to as CRISPRi under a neuron-specific promoter, and a second construct delivering a U6-driven sgRNA (single guide RNA) alongside an elongation factor 1 alpha (EF1α)-driven mCherry reporter. We detail the design, production, and stereotaxic delivery of these tools and demonstrate their application by targeting four genes implicated in social behavior (Oxtr, Avpr1a, Drd1, and Drd2) across two mesolimbic brain regions: the nucleus accumbens and ventral pallidum. Gene expression analyses confirmed robust, bidirectional transcriptional modulation for selected targets, establishing a proof of concept for CRISPRa/i in this non-traditional model. The dual-vector design is readily adaptable to other gene targets, cell types, and brain regions, and can be multiplexed to provide a flexible and scalable framework for investigating gene function in behaviorally relevant circuits. These advances represent the first successful implementation of somatic CRISPRa/i in prairie voles and expand the genetic toolkit available for this species.

Avpr1a↗