Two inducible CRISPR-based perturbation platforms are characterized in K562 human hematopoietic cells: dual-inducible CRISPRi system employing a dCas9–KRAB–DHFR–TetON architecture controlled by doxycycline and trimethoprim and single-inducible CRISPRa system employing a dCas9–VPR–TetON architecture controlled by Dox alone.
A novel genome-wide CRISPR screening strategy that will facilitate the systematic engineering of novel nonviral genome editing delivery methods, where the identified novel gene hits can be further used to increase editing efficiency for other therapeutically relevant cell types.
Shivani Saxena, Meha Kabra, Amr A. Abdeen et al.· bioRxiv· 2 citations
To systematically map cellular factors constraining nonviral genome editing, influencing uptake and intracellular trafficking, we develop a genome-wide CRISPR screening platform linking perturbation of 19,114 genes to editing outcomes in human cells. We identify six negative regulators of delivery whose depletion increases editing efficiency by up to six-fold across diverse payloads, loci, and cell types. We test the top two factors, GJB2 and BET1L, in two distinct human models: correction of a pathogenic adenine base mutation in KCNJ13 and introduction of a cytosine base mutation in the GABAA receptor gene. Depletion of either improves base-editing outcomes by 6-fold, potentially through effects on delivery. In a patient-derived model of retinal channelopathy, knockdown of either gene improves lipid nanoparticle base editing efficiency by over 3.5-fold. This enables functional restoration of Kir7.1 ion channels in a subset of edited cells, highlighting cellular barriers as actionable targets to enhance the potency of genetic therapies. Low editing efficiency of nonviral delivery in post mitotic tissues presents a challenge to the field of gene therapy. Here, authors dissect the genetic regulators of nonviral delivery in post mitotic retinal epithelial cells describe strategies for improved base editor delivery and editing.
Shivani Saxena, Meha Kabra, Amr A. Abdeen et al.· Nature Communications· 0 citations
Human induced pluripotent stem cells (hiPSCs) represent a powerful platform for disease modeling, especially in monogenic diseases as they preserve the donor’s genetic background while enabling directed differentiation into disease-relevant cell types. This makes them highly suitable for studying disease mechanisms in a patient-specific and physiologically relevant context. Although CRISPR/Cas9 is widely applied for genome editing, precise correction of pathogenic variants in hiPSCs remains challenging due to the lack of standardized CRISPR component selection and experimental design. Here, we describe an optimized CRISPR-based strategy for correcting a heterozygous HNF1A frameshift mutation (c.235_236insG; p.Glu79Glyfs*16) in HNF1A-MODY patient-derived hiPSCs. Using electroporation, we efficiently delivered CRISPR components, including a ribonucleoprotein complex of Cas9 and single-guide RNA, along with a single-stranded oligodeoxynucleotide repair template. Corrected hiPSC lines were validated for pluripotency, absence of exogenous reprogramming factors, and off-target effects. Additionally, we discuss key technical challenges encountered during the editing process and provide practical recommendations that may improve the generation of mutation-corrected hiPSC lines. These guidelines could serve as a useful reference for researchers employing CRISPR-based strategies for generation of reliable disease modelling tools.
D. Skoczek, Jerzy Hohendorff, Maciej T. Małecki et al.· Human Genetics· 0 citations
The CRISPR-condensate system merges the dramatically enhanced transcriptional efficacy with the reduced complexity of components, providing a modular system for fine-tuned gene expression regulation and makes biomolecular condensation a general principle for enhancing CRISPR gene regulation.
Aolin Li, Congcong Cao, Chunyan Yang et al.· Theranostics· 0 citations
The potential application of CRISPR technology for the possible management of geneticbased conditions, including sickle-cell anemia, β-thalassemia, cystic fibrosis, and Duchenne muscular dystrophy is described.
M. Veer, Poonam Nikam, Omkar More et al.· International Journal of Dru...· 0 citations