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1.
ACS Nano ; 18(21): 13950-13965, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38751197

RESUMO

Manipulating the expression of cellular genes through efficient CRISPR/Cas9 delivery is rapidly evolving into a desirable tumor therapeutics. The exposure of CRISPR/Cas9 to a complex external environment poses challenges for conventional delivery carriers in achieving responsive and accurate release. Here, we report a Trojan horse-like nanocapsule for the on-demand delivery of CRISPR/Cas9 in a microRNA-responsive manner, enabling precise tumor therapy. The nanocapsule comprises a nanoassembled, engineered DNAzyme shell encasing a Cas9/sgRNA complex core. The DNAzyme, functioning as a catalytic unit, undergoes a conformational change in the presence of tumor-associated microRNA, followed by activating a positive feedback-driven autonomous catabolic cycle of the nanocapsule shell. This catabolic cycle is accomplished through chain reactions of DNAzyme "cleavage-hybridization-cleavage", which ensures sensitivity in microRNA recognition and effective release of Cas9/sgRNA. Utilizing this Trojan horse-like nanocapsule, as low as 1.7 pM microRNA-21 can trigger the on-demand release of Cas9/sgRNA, enabling the specific editing of the protumorigenic microRNA coding gene. The resulting upregulation of tumor suppressor genes induces apoptosis in tumor cells, leading to significant inhibition of tumor growth by up to 75.94%. The Trojan horse-like nanocapsule, with superior programmability and biocompatibility, is anticipated to serve as a promising carrier for tailoring responsive gene editing systems, achieving enhanced antitumor specificity and efficacy.


Assuntos
Sistemas CRISPR-Cas , DNA Catalítico , MicroRNAs , Nanocápsulas , Sistemas CRISPR-Cas/genética , DNA Catalítico/química , DNA Catalítico/metabolismo , Humanos , Nanocápsulas/química , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , Camundongos , Edição de Genes , Proteína 9 Associada à CRISPR/metabolismo , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/química
2.
Nat Commun ; 15(1): 3478, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658578

RESUMO

The expansion of the CRISPR-Cas toolbox is highly needed to accelerate the development of therapies for genetic diseases. Here, through the interrogation of a massively expanded repository of metagenome-assembled genomes, mostly from human microbiomes, we uncover a large variety (n = 17,173) of type II CRISPR-Cas loci. Among these we identify CoCas9, a strongly active and high-fidelity nuclease with reduced molecular size (1004 amino acids) isolated from an uncultivated Collinsella species. CoCas9 is efficiently co-delivered with its sgRNA through adeno associated viral (AAV) vectors, obtaining efficient in vivo editing in the mouse retina. With this study we uncover a collection of previously uncharacterized Cas9 nucleases, including CoCas9, which enriches the genome editing toolbox.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Microbiota , Edição de Genes/métodos , Humanos , Animais , Camundongos , Microbiota/genética , Dependovirus/genética , Proteína 9 Associada à CRISPR/metabolismo , Proteína 9 Associada à CRISPR/genética , RNA Guia de Sistemas CRISPR-Cas/genética , RNA Guia de Sistemas CRISPR-Cas/metabolismo , Retina/metabolismo , Clostridiales/genética , Clostridiales/enzimologia , Células HEK293 , Vetores Genéticos/metabolismo , Vetores Genéticos/genética
3.
Genome Biol ; 25(1): 108, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671524

RESUMO

BACKGROUND: Prime editing enables precise base substitutions, insertions, and deletions at targeted sites without the involvement of double-strand DNA breaks or exogenous donor DNA templates. However, the large size of prime editors (PEs) hampers their delivery in vivo via adeno-associated virus (AAV) due to the viral packaging limit. Previously reported split PE versions provide a size reduction, but they require intricate engineering and potentially compromise editing efficiency. RESULTS: Herein, we present a simplified split PE named as CC-PE, created through non-covalent recruitment of reverse transcriptase to the Cas9 nickase via coiled-coil heterodimers, which are widely used in protein design due to their modularity and well-understood sequence-structure relationship. We demonstrate that the CC-PE maintains or even surpasses the efficiency of unsplit PE in installing intended edits, with no increase in the levels of undesired byproducts within tested loci amongst a variety of cell types (HEK293T, A549, HCT116, and U2OS). Furthermore, coiled-coil heterodimers are used to engineer SpCas9-NG-PE and SpRY-PE, two Cas9 variants with more flexible editing scope. Similarly, the resulting NG-CC-PE and SpRY-CC-PE also achieve equivalent or enhanced efficiency of precise editing compared to the intact PE. When the dual AAV vectors carrying CC-PE are delivered into mice to target the Pcsk9 gene in the liver, CC-PE enables highly efficient precise editing, resulting in a significant reduction of plasma low-density lipoprotein cholesterol and total cholesterol. CONCLUSIONS: Our innovative, modular system enhances flexibility, thus potentially facilitating the in vivo applicability of prime editing.


Assuntos
Edição de Genes , Humanos , Animais , Camundongos , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas , Células HEK293 , Dependovirus/genética
4.
Proc Natl Acad Sci U S A ; 121(19): e2321438121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38687782

RESUMO

Successful CRISPR/Cas9-based gene editing in skeletal muscle is dependent on efficient propagation of Cas9 to all myonuclei in the myofiber. However, nuclear-targeted gene therapy cargos are strongly restricted to their myonuclear domain of origin. By screening nuclear localization signals and nuclear export signals, we identify "Myospreader," a combination of short peptide sequences that promotes myonuclear propagation. Appending Myospreader to Cas9 enhances protein stability and myonuclear propagation in myoblasts and myofibers. AAV-delivered Myospreader dCas9 better inhibits transcription of toxic RNA in a myotonic dystrophy mouse model. Furthermore, Myospreader Cas9 achieves higher rates of gene editing in CRISPR reporter and Duchenne muscular dystrophy mouse models. Myospreader reveals design principles relevant to all nuclear-targeted gene therapies and highlights the importance of the spatial dimension in therapeutic development.


Assuntos
Sistemas CRISPR-Cas , Núcleo Celular , Edição de Genes , Terapia Genética , Músculo Esquelético , Distrofia Muscular de Duchenne , Edição de Genes/métodos , Animais , Camundongos , Músculo Esquelético/metabolismo , Núcleo Celular/metabolismo , Terapia Genética/métodos , Distrofia Muscular de Duchenne/terapia , Distrofia Muscular de Duchenne/genética , Humanos , Sinais de Localização Nuclear/genética , Proteína 9 Associada à CRISPR/metabolismo , Proteína 9 Associada à CRISPR/genética , Modelos Animais de Doenças , Mioblastos/metabolismo
5.
Mol Cell ; 84(8): 1585-1600.e7, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38479385

RESUMO

Myriad physiological and pathogenic processes are governed by protein levels and modifications. Controlled protein activity perturbation is essential to studying protein function in cells and animals. Based on Trim-Away technology, we screened for truncation variants of E3 ubiquitinase Trim21 with elevated efficiency (ΔTrim21) and developed multiple ΔTrim21-based targeted protein-degradation systems (ΔTrim-TPD) that can be transfected into host cells. Three ΔTrim-TPD variants are developed to enable chemical and light-triggered programmable activation of TPD in cells and animals. Specifically, we used ΔTrim-TPD for (1) red-light-triggered inhibition of HSV-1 virus proliferation by degrading the packaging protein gD, (2) for chemical-triggered control of the activity of Cas9/dCas9 protein for gene editing, and (3) for blue-light-triggered degradation of two tumor-associated proteins for spatiotemporal inhibition of melanoma tumor growth in mice. Our study demonstrates that multiple ΔTrim21-based controllable TPD systems provide powerful tools for basic biology research and highlight their potential biomedical applications.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Camundongos , Animais , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Proteínas/metabolismo , Proteólise , Mamíferos/metabolismo
6.
Chembiochem ; 25(10): e202400149, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38530114

RESUMO

Labeling of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) associated proteins (Cas) remains an immense challenge for their genome engineering applications. To date, cysteine-mediated bioconjugation is the most efficient strategy for labeling Cas proteins. However, introducing a cysteine residue in the protein at the right place might be challenging without perturbing the enzymatic activity. We report a method that does not require cysteine residues for small molecule presentation on the CRISPR-associated protein SpCas9 for in vitro protein detection, probing cellular protein expression, and nuclear co-delivery of molecules in mammalian cells. We repurposed a simple protein purification tag His6 peptide for non-covalent labeling of molecules on the CRISPR enzyme SpCas9. The small molecule labeling enabled us to rapidly detect SpCas9 in a biochemical assay. We demonstrate that small molecule labeling can be utilized for probing bacterial protein expression in realtime. Furthermore, we coupled SpCas9's nuclear-targeting ability in co-delivering the presenting small molecules to the mammalian cell nucleus for prospective genome engineering applications. Furthermore, we demonstrate that the method can be generalized to label oligonucleotides for multiplexing CRISPR-based genome editing and template-mediated DNA repair applications. This work paves the way for genomic loci-specific bioactive small molecule and oligonucleotide co-delivery toward genetic and epigenetic regulations.


Assuntos
Sistemas CRISPR-Cas , Cisteína , Epigênese Genética , Humanos , Cisteína/química , Cisteína/metabolismo , Sistemas CRISPR-Cas/genética , Proteína 9 Associada à CRISPR/metabolismo , Proteína 9 Associada à CRISPR/genética , Células HEK293 , Edição de Genes/métodos
7.
J Pept Sci ; 30(7): e3592, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38447547

RESUMO

The CRISPR-Cas9 system has revolutionized the field of genetic engineering, but targeted cellular delivery remains a central problem. The delivery of the preformed ribonuclease-protein (RNP) complex has the advantages of fewer side effects and avoidance of potential permanent effects. We reasoned that an internalizing IgG antibody as a targeting device could address the delivery of Cas9-RNP. We opted for protein trans-splicing mediated by a split intein to facilitate posttranslational conjugation of the two large protein entities. We recently described the cysteine-less CL split intein that efficiently performs under oxidizing conditions and does not interfere with disulfide bonds or thiol bioconjugation chemistries. Using the CL split intein, we report for the first time the ligation of monoclonal IgG antibody precursors, expressed in mammalian cells, and a Cas9 precursor, obtained from bacterial expression. A purified IgG-Cas9 conjugate was loaded with sgRNA to form the active RNP complex and introduced a double-strand break in its target DNA in vitro. Furthermore, a synthetic peptide variant of the short N-terminal split intein precursor proved useful for chemical modification of Cas9. The split intein ligation procedure reported here for IgG-Cas9 provides the first step towards a novel CRISPR-Cas9 targeting approach involving the preformed RNP complex.


Assuntos
Sistemas CRISPR-Cas , Imunoglobulina G , Inteínas , Imunoglobulina G/química , Imunoglobulina G/genética , Humanos , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Proteína 9 Associada à CRISPR/química
8.
Nat Chem Biol ; 20(3): 333-343, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37735239

RESUMO

CRISPR-Cas9 genome engineering is a powerful technology for correcting genetic diseases. However, the targeting range of Cas9 proteins is limited by their requirement for a protospacer adjacent motif (PAM), and in vivo delivery is challenging due to their large size. Here, we use phage-assisted continuous directed evolution to broaden the PAM compatibility of Campylobacter jejuni Cas9 (CjCas9), the smallest Cas9 ortholog characterized to date. The identified variant, termed evoCjCas9, primarily recognizes N4AH and N5HA PAM sequences, which occur tenfold more frequently in the genome than the canonical N3VRYAC PAM site. Moreover, evoCjCas9 exhibits higher nuclease activity than wild-type CjCas9 on canonical PAMs, with editing rates comparable to commonly used PAM-relaxed SpCas9 variants. Combined with deaminases or reverse transcriptases, evoCjCas9 enables robust base and prime editing, with the small size of evoCjCas9 base editors allowing for tissue-specific installation of A-to-G or C-to-T transition mutations from single adeno-associated virus vector systems.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , Mutação , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Genoma
9.
J Thromb Haemost ; 22(4): 951-964, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38104724

RESUMO

BACKGROUND: Pituitary adenylate cyclase-activating polypeptide is a neuropeptide with diverse roles in biological processes. Its involvement in the blood coagulation cascade is unclear. OBJECTIVES: This study unraveled adcyap1b's role in blood coagulation using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 in zebrafish. Effects were validated via adcyap1b knockdown. Gene expression changes in adcyap1b mutants were explored, linking them to clotting disorders. An analysis of proca gene splicing illuminated its role in adcyap1b-related anticoagulation deficiencies. METHODS: Zebrafish were genetically modified using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 to induce adcyap1b knockout. Morpholino-mediated gene knockdown was employed for validation. Expression levels of coagulation factors, anticoagulant proteins, and fibrinolytic system genes were assessed in adcyap1b mutant zebrafish. Alternative splicing of proca gene was analyzed. RESULTS: Adcyap1b mutant zebrafish exhibited severe hemorrhage, clotting disorders, and disrupted blood coagulation. Morpholino-mediated knockdown replicated observed phenotypes. Downregulation in transcripts related to coagulation factors V and IX, anticoagulation protein C, and plasminogen was observed. Abnormal alternative splicing of the proca gene was identified, providing a mechanistic explanation for anticoagulation system deficiencies. CONCLUSION: Adcyap1b plays a crucial role in maintaining zebrafish blood coagulation and hemostasis. Its influence extends to the regulation of procoagulant and anticoagulant pathways, with abnormal alternative splicing contributing to observed deficiencies. These findings unveil a novel aspect of adcyap1b function, offering potential insights into similar processes in mammalian systems.


Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteína 9 Associada à CRISPR/metabolismo , Morfolinos/genética , Morfolinos/metabolismo , Coagulação Sanguínea/genética , Fator V/metabolismo , Hemorragia , Anticoagulantes/metabolismo , Mamíferos/metabolismo
10.
Nanomedicine ; 54: 102711, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37813236

RESUMO

For the past decades, gene editing demonstrated the potential to attenuate each of the root causes of genetic, infectious, immune, cancerous, and degenerative disorders. More recently, Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-associated protein 9 (CRISPR-Cas9) editing proved effective for editing genomic, cancerous, or microbial DNA to limit disease onset or spread. However, the strategies to deliver CRISPR-Cas9 cargos and elicit protective immune responses requires safe delivery to disease targeted cells and tissues. While viral vector-based systems and viral particles demonstrate high efficiency and stable transgene expression, each are limited in their packaging capacities and secondary untoward immune responses. In contrast, the nonviral vector lipid nanoparticles were successfully used for as vaccine and therapeutic deliverables. Herein, we highlight each available gene delivery systems for treating and preventing a broad range of infectious, inflammatory, genetic, and degenerative diseases. STATEMENT OF SIGNIFICANCE: CRISPR-Cas9 gene editing for disease treatment and prevention is an emerging field that can change the outcome of many chronic debilitating disorders.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Técnicas de Transferência de Genes , Terapia Genética
11.
Nat Protoc ; 18(11): 3194-3228, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37794072

RESUMO

Fusing apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like cytidine deaminase with catalytically impaired Cas proteins (e.g., nCas9 or dCas9) provides a novel gene-editing technology, base editing, that grants targeted base substitutions with high efficiency. However, genome-wide and transcriptome-wide off-target mutations are observed in base editing, which raises safety concerns regarding therapeutic applications. Previously, we developed a new base editing system, the transformer base editor (tBE), to induce efficient editing with no observable genome-wide or transcriptome-wide off-target mutations both in mammalian cells and in mice. Here we describe a detailed protocol for the design and application of the tBE. Steps for designing single-guide RNA (sgRNA) and helper sgRNA pairs, making constructs, determining the genome-wide and transcriptome-wide off-target mutations, producing the tBE-containing adeno-associated viruses, delivering adeno-associated viruses into mice and examining the in vivo editing effects are included in this protocol. High-precision base editing by the tBE can be completed within 2-3 weeks (in mammalian cells) or within 6-8 weeks (in mice), with sgRNA-helper sgRNA pairs. The whole process can be collaboratively accomplished by researchers using standard techniques from molecular biology, bioinformatics and mouse husbandry.


Assuntos
Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , Camundongos , Animais , Edição de Genes/métodos , Proteína 9 Associada à CRISPR/metabolismo , Mutação , Mamíferos/genética
12.
Int J Mol Sci ; 24(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37108214

RESUMO

The innovative advances in transforming clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9) into different variants have taken the art of genome-editing specificity to new heights. Allosteric modulation of Cas9-targeting specificity by sgRNA sequence alterations and protospacer adjacent motif (PAM) modifications have been a good lesson to learn about specificity and activity scores in different Cas9 variants. Some of the high-fidelity Cas9 variants have been ranked as Sniper-Cas9, eSpCas9 (1.1), SpCas9-HF1, HypaCas9, xCas9, and evoCas9. However, the selection of an ideal Cas9 variant for a given target sequence remains a challenging task. A safe and efficient delivery system for the CRISPR/Cas9 complex at tumor target sites faces considerable challenges, and nanotechnology-based stimuli-responsive delivery approaches have significantly contributed to cancer management. Recent innovations in nanoformulation design, such as pH, glutathione (GSH), photo, thermal, and magnetic responsive systems, have modernized the art of CRISPR/Cas9 delivery approaches. These nanoformulations possess enhanced cellular internalization, endosomal membrane disruption/bypass, and controlled release. In this review, we aim to elaborate on different CRISPR/Cas9 variants and advances in stimuli-responsive nanoformulations for the specific delivery of this endonuclease system. Furthermore, the critical constraints of this endonuclease system on clinical translations towards the management of cancer and prospects are described.


Assuntos
Sistemas CRISPR-Cas , Neoplasias , Humanos , Sistemas CRISPR-Cas/genética , Proteína 9 Associada à CRISPR/metabolismo , Edição de Genes , Neoplasias/genética , Neoplasias/terapia , Tecnologia
13.
Nat Commun ; 14(1): 2046, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041195

RESUMO

The type V-F CRISPR-Cas12f system is a strong candidate for therapeutic applications due to the compact size of the Cas12f proteins. In this work, we identify six uncharacterized Cas12f1 proteins with nuclease activity in mammalian cells from assembled bacterial genomes. Among them, OsCas12f1 (433 aa) from Oscillibacter sp. and RhCas12f1 (415 aa) from Ruminiclostridium herbifermentans, which respectively target 5' T-rich Protospacer Adjacent Motifs (PAMs) and 5' C-rich PAMs, show the highest editing activity. Through protein and sgRNA engineering, we generate enhanced OsCas12f1 (enOsCas12f1) and enRhCas12f1 variants, with 5'-TTN and 5'-CCD (D = not C) PAMs respectively, exhibiting much higher editing efficiency and broader PAMs, compared with the engineered variant Un1Cas12f1 (Un1Cas12f1_ge4.1). Furthermore, by fusing the destabilized domain with enOsCas12f1, we generate inducible-enOsCas12f1 and demonstate its activity in vivo by single adeno-associated virus delivery. Finally, dead enOsCas12f1-based epigenetic editing and gene activation can also be achieved in mammalian cells. This study thus provides compact gene editing tools for basic research with remarkable promise for therapeutic applications.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Genoma Bacteriano , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Proteína 9 Associada à CRISPR/metabolismo , Dependovirus/genética , Edição de Genes/métodos , Mamíferos/genética , Genoma Bacteriano/fisiologia
14.
Nature ; 616(7956): 357-364, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36991127

RESUMO

Endosymbiotic bacteria have evolved intricate delivery systems that enable these organisms to interface with host biology. One example, the extracellular contractile injection systems (eCISs), are syringe-like macromolecular complexes that inject protein payloads into eukaryotic cells by driving a spike through the cellular membrane. Recently, eCISs have been found to target mouse cells1-3, raising the possibility that these systems could be harnessed for therapeutic protein delivery. However, whether eCISs can function in human cells remains unknown, and the mechanism by which these systems recognize target cells is poorly understood. Here we show that target selection by the Photorhabdus virulence cassette (PVC)-an eCIS from the entomopathogenic bacterium Photorhabdus asymbiotica-is mediated by specific recognition of a target receptor by a distal binding element of the PVC tail fibre. Furthermore, using in silico structure-guided engineering of the tail fibre, we show that PVCs can be reprogrammed to target organisms not natively targeted by these systems-including human cells and mice-with efficiencies approaching 100%. Finally, we show that PVCs can load diverse protein payloads, including Cas9, base editors and toxins, and can functionally deliver them into human cells. Our results demonstrate that PVCs are programmable protein delivery devices with possible applications in gene therapy, cancer therapy and biocontrol.


Assuntos
Membrana Celular , Sistemas de Liberação de Medicamentos , Células Eucarióticas , Photorhabdus , Proteínas , Animais , Humanos , Camundongos , Membrana Celular/metabolismo , Células Eucarióticas/citologia , Células Eucarióticas/metabolismo , Photorhabdus/química , Photorhabdus/metabolismo , Proteína 9 Associada à CRISPR/metabolismo , Toxinas Biológicas/metabolismo , Proteínas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Transporte Proteico
15.
Exp Mol Med ; 55(2): 377-384, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36720917

RESUMO

Various CRISPR‒Cas9 orthologs are used in genome engineering. One of the smallest Cas9 orthologs is cjCas9 derived from Campylobacter jejuni, which is a highly specific genome editing tool. Here, we developed cjCas9-based base editors including a cytosine base editor (cjCBEmax) and an adenine base editor (cjABE8e) that can successfully induce endogenous base substitutions by up to 91.2% at the HPD gene in HEK293T cells. Analysis of the base editing efficiency of 13 endogenous target sites showed that the active windows of cjCBEmax and cjABE8e are wider than those of spCas9-based base editors and that their specificities are slightly lower than that of cjCas9. Importantly, engineered cjCas9 and gRNA scaffolds can improve the base editing efficiency of cjABE8e by up to 6.4-fold at the HIF1A gene in HEK293T cells. Due to its small size, cjABE8e can be packaged in a single adeno-associated virus vector with two tandem arrays of gRNAs, and the delivery of the resulting AAV could introduce base substitutions at endogenous ANGPT2 and HPD target sites. Overall, our findings have expanded the potential of the use of base editors for in vivo or ex vivo therapeutic approaches.


Assuntos
Campylobacter jejuni , Edição de Genes , Humanos , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Células HEK293 , RNA Guia de Sistemas CRISPR-Cas
16.
Mol Ther ; 31(3): 744-759, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457249

RESUMO

Editing efficiency is pivotal for the efficacies of CRISPR-based gene therapies. We found that fusing an HMG-D domain to the N terminus of SpCas9 (named efficiency-enhanced Cas9 [eeCas9]) significantly increased editing efficiency by 1.4-fold on average. The HMG-D domain also enhanced the activities of non-NGG PAM Cas9 variants, high-fidelity Cas9 variants, smaller Cas9 orthologs, Cas9-based epigenetic regulators, and base editors in cell lines. Furthermore, we discovered that eeCas9 exhibits comparable off-targeting effects with Cas9, and its specificity could be increased through ribonucleoprotein delivery or using hairpin single-guide RNAs and high-fidelity Cas9s. The entire eeCas9 could be packaged into an adeno-associated virus vector and exhibited a 1.7- to 2.6-fold increase in editing efficiency targeting the Pcsk9 gene in mice, leading to a greater reduction of serum cholesterol levels. Moreover, the efficiency of eeA3A-BE3 also surpasses that of A3A-BE3 in targeting the promoter region of γ-globin genes or BCL11A enhancer in human hematopoietic stem cells to reactivate γ-globin expression for the treatment of ß-hemoglobinopathy. Together, eeCas9 and its derivatives are promising editing tools that exhibit higher activity and therapeutic efficacy for both in vivo and ex vivo therapeutics.


Assuntos
Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Animais , Humanos , Camundongos , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Edição de Genes , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , gama-Globinas/genética , Terapia Genética
17.
Nat Commun ; 13(1): 7071, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36400778

RESUMO

Anti-CRISPRs (Acrs) are natural inhibitors of bacteria's CRISPR-Cas systems, and have been developed as a safeguard to reduce the off-target effects of CRISPR gene-editing technology. Acrs can directly bind to CRISPR-Cas complexes and inhibit their activities. However, whether this process is under regulation in diverse eukaryotic cellular environments is poorly understood. In this work, we report the discovery of a redox switch for NmeAcrIIC1, which regulates NmeAcrIIC1's monomer-dimer interconversion and inhibitory activity on Cas9. Further structural studies reveal that a pair of conserved cysteines mediates the formation of inactive NmeAcrIIC1 dimer and directs the redox cycle. The redox switch also applies to the other two AcrIIC1 orthologs. Moreover, by replacing the redox-sensitive cysteines, we generated a robust AcrIIC1 variant that maintains potent inhibitory activity under various redox conditions. Our results reveal a redox-dependent regulation mechanism of Acr, and shed light on the design of superior Acr for CRISPR-Cas systems.


Assuntos
Proteína 9 Associada à CRISPR , Edição de Genes , Proteína 9 Associada à CRISPR/metabolismo , Edição de Genes/métodos , Sistemas CRISPR-Cas , Oxirredução
19.
Acta Biomater ; 154: 597-607, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36243370

RESUMO

The CRISPR/Cas9 mediated genome editing have provided a promising strategy to correct multiple mutations of Duchenne muscular dystrophy (DMD). However, the delivery of CRISPR/Cas9 system into mammalian cell for DMD gene editing mainly relies on adeno associated virus (AAV)-mediated transport. Meanwhile, the protospacer adjacent motif (PAM) requirement of wild-typed Cas9 protein causing the target sites for exon splice acceptor site are restricted to limited regions. Here, we developed a biomineralized PAMLess Cas9 (SpRY) variant nanoparticles (Bm-SpRY NPs) for DMD gene editing in vitro and in vivo. This method described a facile synthesis of biomineralized NPs with high SpRY pDNA encapsulation efficiency. In vitro results show that the Bm-SpRY NPs have the obvious advantages of well biocompatibility and protecting SpRY pDNA from enzyme degradation and efficient delivery under high serum condition. Cell studies demonstrated that Bm-SpRY NPs enable rapid cellular uptake, endo-lysosomes escape and nucleus transport. Meanwhiles, the DMD gene editing via Bm-SpRY NPs pathway is transient process without genomic integration. We evaluated multiple target regions with different PAMs for the DMD exon 51 splice acceptor site through Bm-SpRY NPs method and found that the target region with TAG PAM has the highest editing efficiency and significant preferential mutation. In vivo results show that intramuscular injection of Bm-SpRY NPs enable DMD gene mutation in muscle tissue without tissue damage. This study may extend the advanced application of CRISPR system for DMD therapy. STATEMENT OF SIGNIFICANCE: The gene editing technology of CRISPR/Cas9 provides an effective treatment strategy for the Duchenne muscular dystrophy (DMD) therapy. However, the delivery of CRISPR system in mammalian cell mainly relies on viral mediated transport and the NGG or NAG requirement of wild-typed Cas9 protein limits the target region in DMD gene. Here, the present study provides a biomineralized PAM Less Cas9 (SpRY) variant nanoparticles (Bm-SpRY NPs) for DMD gene editing in vitro and in vivo. This study may extend the application of CRISPR system for DMD gene therapy.


Assuntos
Edição de Genes , Distrofia Muscular de Duchenne , Animais , Edição de Genes/métodos , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/terapia , Distrofia Muscular de Duchenne/metabolismo , Proteína 9 Associada à CRISPR/metabolismo , Distrofina/genética , Distrofina/metabolismo , Sistemas CRISPR-Cas/genética , Sítios de Splice de RNA , Mamíferos/metabolismo
20.
Cancer Commun (Lond) ; 42(12): 1257-1287, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36209487

RESUMO

Clustered regularly interspaced short palindromic repeats-associated protein (CRISPR/Cas9), an adaptive microbial immune system, has been exploited as a robust, accurate, efficient and programmable method for genome targeting and editing. This innovative and revolutionary technique can play a significant role in animal modeling, in vivo genome therapy, engineered cell therapy, cancer diagnosis and treatment. The CRISPR/Cas9 endonuclease system targets a specific genomic locus by single guide RNA (sgRNA), forming a heteroduplex with target DNA. The Streptococcus pyogenes Cas9/sgRNA:DNA complex reveals a bilobed architecture with target recognition and nuclease lobes. CRISPR/Cas9 assembly can be hijacked, and its nanoformulation can be engineered as a delivery system for different clinical utilizations. However, the efficient and safe delivery of the CRISPR/Cas9 system to target tissues and cancer cells is very challenging, limiting its clinical utilization. Viral delivery strategies of this system may have many advantages, but disadvantages such as immune system stimulation, tumor promotion risk and small insertion size outweigh these advantages. Thus, there is a desperate need to develop an efficient non-viral physical delivery system based on simple nanoformulations. The delivery strategies of CRISPR/Cas9 by a nanoparticle-based system have shown tremendous potential, such as easy and large-scale production, combination therapy, large insertion size and efficient in vivo applications. This review aims to provide in-depth updates on Streptococcus pyogenic CRISPR/Cas9 structure and its mechanistic understanding. In addition, the advances in its nanoformulation-based delivery systems, including lipid-based, polymeric structures and rigid NPs coupled to special ligands such as aptamers, TAT peptides and cell-penetrating peptides, are discussed. Furthermore, the clinical applications in different cancers, clinical trials and future prospects of CRISPR/Cas9 delivery and genome targeting are also discussed.


Assuntos
Edição de Genes , Neoplasias , Animais , Edição de Genes/métodos , Sistemas CRISPR-Cas , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , DNA , Neoplasias/genética , Neoplasias/terapia
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