Nature Biotechnology即中國學者高彩霞單堿基突變Precise Base Editing in Rice, Wheat and Maize with a Cas9- cytidine Deaminase Fusion 文章發表之后，
Increasing the genome-targeting scope and precision of base editing with engineered Cas9-cytidine deaminase fusions
· PDF 檔案Cas9-cytidine deaminase fusions The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Kim, Y. Bill, Alexis C. Komor, Jonathan M. Levy, Michael S. Packer, Kevin T. Zhao, and
Base editing in Streptomyces with Cas9-deaminase fusions
· PDF 檔案editing (BE)” in which the fusion of a cytidine deaminase to a Cas9 variant enables programmable C•G → T•A base-pair conversion without the need for DSB formation or template donor DNA10,11 (Fig. 1a). In its initial formulation the base editor (BE1) tethers a
Description of CRISPR/Cas9 development and its …
· Cytidine deaminase exchanges cytosine to uracil and achieves single base editing during DNA replication. Abbreviations: sgRNA, single strand RNA; PAMs, protospacer adjacent motifs; dCas9, dead Cas9 protein
Genome editing: A perspective on the application of …
Among other modifications to date, the SpCas9-cytidine deaminase can be found, which is a fusion of dSpCas9 with the cytidine deaminase enzyme. This action by cytidine deaminases, converts cytosine (C) to uracil (U), working on single-stranded DNA accessible in the ternary complex between Cas9, gRNA and the target DNA for the introduction of point mutations ( 77 ).
A bacterial cytidine deaminase toxin enables CRISPR …
Such proteins include a group of predicted interbacterial toxins of the deaminase superfamily, members of which have found application in gene-editing techniques 1,2 . Because previously described cytidine deaminases operate on single-stranded nucleic acids3, their use in base editing requires the unwinding of double-stranded DNA (dsDNA)—for example by a CRISPR-Cas9 system.
First CRISPR Single-Nucleotide Edited Transgenic Mice
This Cas9 cuts only one filament of the DNA and the cytidine deaminase modifies one nucleotide (from cytosine to thymine, T), producing a DNA of the same length with only one nucleotide difference. The scientists tested the CRISPR-nCas9-cytidine deaminase fusion in mice by changing a single nucleotide in the dystrophin gene ( Dmd ) or the tyrosinase gene ( Tyr ).
Highly efficient DSB-free base editing for streptomycetes with …
· PDF 檔案APOBEC1 (rAPOBEC1) cytidine deaminase, a Cas9 nickase (Cas9n), and a uracil glycosylase inhibitor (UGI) (19), while ABE7.10 was established by fusing of the laboratory evolved Escherichia coli adenosine deaminase TadA (ecTadA) and a Cas9n (20
Nature Biotechnology單堿基編輯系統成功在水稻和番茄 …
最近，成功在水稻和番茄中實現了單堿基的編輯。
Programmable editing of a target base in genomic DNA without …
· PDF 檔案of CRISPR/Cas9 and a cytidine deaminase enzyme that retain the ability to be programmed with a guide RNA, do not induce dsDNA breaks, and mediate the direct conversion of cytidine to uridine, thereby effecting a C→T (or G→A) substitution.
Development and Characterization of a Modular CRISPR …
· Zong Y, Wang Y, Li C, et al. Precise base editing in rice, wheat and maize with a Cas9-cytidine deaminase fusion. Nat Biotechnol 2017 ;35:438. DOI: 10.1038/nbt.3811 .
Potato Virus X Vector-Mediated DNA-Free Genome …
The PVX vector was also used to express a base editor consisting of modified Cas9 fused with cytidine deaminase to introduce targeted nucleotide substitution in regenerated shoots. We also report exogenous DNA-free genome editing by mechanical inoculation of virions comprising the PVX vector expressing Cas9.
A cytosine deaminase for programmable single-base …
A previously developed RNA editing system called REPAIR can base edit A to I in RNA by fusing the adenine deaminase domain of ADAR2 with catalytically dead CRISPR-Cas13. Using directed evolution, Abudayyeh et al. demonstrated that the ADAR2 deaminase domain can be relaxed to accept other bases. This resulted in cytidine deamination activity, expanding the RNA editing toolbox for C-to-U
DNA Can Be Edited without Being Cut
CRISPR/Cas9 gene-editing system drops nuclease activity, gains cytidine deaminase activity, achieves efficient target-specific mutagenesis without resorting to cleavage. The figure analyzes the
Protein Modeling/CRISPR-Cas9 and Base Editing
· This is where the APOBEC cytidine deaminase enzymes are essential – they can edit a strand of DNA without creating a DSB. However, many of these enzymes only work on RNA or require ssDNA to function. CRISPR-Cas9 can be used to direct these cytidine deaminase enzymes towards specific areas of DNA that have been unpaired, allowing the enzyme to convert the cytosine base to a …
An optimized base editor with efficient C-to-T base …
· Background Zebrafish is a model organism widely used for the understanding of gene function, including the fundamental basis of human disease, enabled by the presence in its genome of a high number of orthologs to human genes. CRISPR/Cas9 and next-generation gene-editing techniques using cytidine deaminase fused with Cas9 nickase provide fast and efficient tools able to induce …
Lineage tracing using a Cas9-deaminase barcoding …
Here, we develop a genome editing strategy using a cytidine deaminase fused with nickase Cas9 (nCas9) to specifically target endogenous interspersed repeat regions in mammalian cells. The resulting mutation patterns serve as a genetic barcode, which is induced by targeted mutagenesis with single-guide RNA (sgRNA), leveraging substitution events, and subsequent read out by a single primer pair.
Activation-induced cytidine deaminase
Activation-induced cytidine deaminase, also known as AICDA, AID and single-stranded DNA cytosine deaminase, is a 24 kDa enzyme which in humans is encoded by the AICDA gene. It creates mutations in DNA by deamination of cytosine base, which turns it into uracil (which is recognized as a thymine).).
Function · ，日本科學家又將該系統Target-AID（target-activation-induced cytidine deaminase）