Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA316460 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Base Editing has been touted the most intelligent and precise application of the CRISPR platform so far, merging the simplicity of RNA-guided nucleases with deaminases that allow for the programmable generation of single base substitutions - without introduction of double-strand breaks. Even though the two-component system has been expected to cause off-target substitutions, studies involving cytosine base editors (CBEs) showed that in most cases, relatively few single base off-targets could be detected on DNA. We introduce the concept of multi-dimensional off-targeting, presenting an extensive amount of RNA cytidines being edited by DNA base editors. Epitranscriptomic off-target effects affected different cell lines and were independent of the guide RNAs used, suggesting Cas9-independent activity of the cytidine deaminase rAPOBEC1 on single-stranded RNA. With the help of protein engineering, we developed CBE variants with massively reduced inadvertent mutation of RNA that preserve and enhance DNA base editing capabilities.
2019-04-01 | GSE129131 | GEO
Project description:Base Editing has been touted the most intelligent and precise application of the CRISPR platform so far, merging the simplicity of RNA-guided nucleases with deaminases that allow for the programmable generation of single base substitutions - without introduction of double-strand breaks. Even though the two-component system has been expected to cause off-target substitutions, studies involving cytosine base editors (CBEs) showed that in most cases, relatively few single base off-targets could be detected on DNA. We introduce the concept of multi-dimensional off-targeting, presenting an extensive amount of RNA cytidines being edited by DNA base editors. Epitranscriptomic off-target effects affected different cell lines and were independent of the guide RNAs used, suggesting Cas9-independent activity of the cytidine deaminase rAPOBEC1 on single-stranded RNA. With the help of protein engineering, we developed CBE variants with massively reduced inadvertent mutation of RNA that preserve and enhance DNA base editing capabilities.
2019-03-31 | GSE121667 | GEO
Project description:Base Editing has been touted the most intelligent and precise application of the CRISPR platform so far, merging the simplicity of RNA-guided nucleases with deaminases that allow for the programmable generation of single base substitutions - without introduction of double-strand breaks. Even though the two-component system has been expected to cause off-target substitutions, studies involving cytosine base editors (CBEs) showed that in most cases, relatively few single base off-targets could be detected on DNA. We introduce the concept of multi-dimensional off-targeting, presenting an extensive amount of RNA cytidines being edited by DNA base editors. Epitranscriptomic off-target effects affected different cell lines and were independent of the guide RNAs used, suggesting Cas9-independent activity of the cytidine deaminase rAPOBEC1 on single-stranded RNA. With the help of protein engineering, we developed CBE variants with massively reduced inadvertent mutation of RNA that preserve and enhance DNA base editing capabilities.
2019-03-31 | GSE121666 | GEO
Project description:Base Editing has been touted the most intelligent and precise application of the CRISPR platform so far, merging the simplicity of RNA-guided nucleases with deaminases that allow for the programmable generation of single base substitutions - without introduction of double-strand breaks. Even though the two-component system has been expected to cause off-target substitutions, studies involving cytosine base editors (CBEs) showed that in most cases, relatively few single base off-targets could be detected on DNA. We introduce the concept of multi-dimensional off-targeting, presenting an extensive amount of RNA cytidines being edited by DNA base editors. Epitranscriptomic off-target effects affected different cell lines and were independent of the guide RNAs used, suggesting Cas9-independent activity of the cytidine deaminase rAPOBEC1 on single-stranded RNA. With the help of protein engineering, we developed CBE variants with massively reduced inadvertent mutation of RNA that preserve and enhance DNA base editing capabilities.
2019-03-31 | GSE121665 | GEO
Project description:Genome editing typically involves recombination between donor nucleic acids and genomic sequences subjected to double-stranded DNA breaks (DSBs) made by programmable nucleases (e.g. CRISPR-Cas9). Yet, amongst other deleterious by-products, DSBs yield translocations, off-target mutations and, most pervasively, unpredictable on-target allelic disruptions. Remarkably, hitherto, the untoward phenotypic consequences of on-target disruptions at allelic and non-allelic (e.g. pseudogene) sequences have received scant scrutiny and, crucially, remain to be addressed. Here, we demonstrate that gene-edited cells can lose fitness due to on-target DSBs and report that simultaneous single-stranded DNA break formation at donor and target DNA by CRISPR-Cas9 “nickases” overcomes, to a great extent, such genotype-phenotype disrupting events. Moreover, in trans paired nicking gene editing can efficiently and precisely add large DNA segments (i.e. live-cell reporter tags) into essential and multiple-copy genomic sequences while circumventing most of the allelic and non-allelic collateral mutations and chromosomal rearrangements characteristic of nuclease-dependent gene editing procedures.
2019-12-04 | GSE135064 | GEO
Project description:Base editing introduces precise single-nucleotide edits in genomic DNA and has the potential to treat genetic diseases such as the blistering skin disease recessive dystrophic epidermolysis bullosa (RDEB), which is characterized by mutations in the COL7A1 gene and type VII collagen (C7) deficiency. Adenine base editors (ABEs) convert A-T base pairs to G-C base pairs without requiring double-stranded DNA breaks or donor DNA templates. Here, we use ABE8e, a recently evolved ABE, to correct primary RDEB fibroblasts harboring the recurrent RDEB nonsense mutation c.5047 C>T (p.Arg1683Ter) in exon 54 of COL7A1 and use a next generation sequencing workflow to interrogate post-treatment outcomes. Electroporation of ABE8e mRNA into a bulk population of RDEB patient fibroblasts resulted in remarkably efficient (94.6%) correction of the pathogenic allele, restoring COL7A1 mRNA and expression of C7 protein in western blots and in 3D skin constructs. Unbiased off-target DNA and RNA editing analysis did not detect off-target editing in treated patient-derived fibroblasts. Taken together, we have established a highly efficient pipeline for gene correction in primary fibroblasts with a favorable safety profile. This work lays a foundation for developing therapies for RDEB patients using ex vivo or in vivo base editing strategies.
2022-08-25 | GSE211876 | GEO