Recent Advances in CRISPR/Cas-based DNA Base Editing

doi:10.13560/j.cnki.biotech.bull.1985.2022-0311

Abstract

Abstract:

CRISPR/Cas-based genome editing has revolutionized biological technology,which is achieved by introducing DSB（double strand break）in target DNA sites followed by cellular DNA repair via non-homologous end joining（NHEJ）or homology-directed repair（HDR）. NHEJ is the main repair pathway in most of cells,it characterized as repair is simple,efficiency is high and it is extremely easy to have errors,and thus presents randomly and unpredictable insertions and deletions（indels）. Point mutations represent the most prevalent form of genetic mutations,which determine the many important agronomic traits in crop plants and cause most of known human genetic diseases. Base editing enables targeted single base substitutions of high efficiency and predicted editing outcomes with neither inducing DSBs in the genomes nor requiring donor templates. Based on its great applicable potentials in the gene therapy,crop breeding as well as basic research,base editing rapidly gains much attentions with numerous applications in agricultural as well as biological fields and considerable progresses having been made to broaden its capabilities. In this review,we summarize the current advances in DNA base editing,focus on improvements in editing efficiency,precision,specificity as well as editing scope,and discuss current limitations and future directions.

Key words: base editing, deaminase, gene editing, CRISPR, CRISPR/Cas

LAI Xin-tong, WANG Ke-lan, YOU Yu-xin, TAN Jun-jie. Recent Advances in CRISPR/Cas-based DNA Base Editing[J]. Biotechnology Bulletin, 2022, 38(6): 1-12.

Figures/Tables 3

References 98

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碱基编辑器名称 Base editor	结构组成 Architecture	编辑窗口 Editing window	序列偏好 Sequence preference	参考文献 Reference
BE3	rAPOBEC1-XTEN-nCas9-UGI	C₄- C₈	TC	^[10]
AID-BE3	hAID-XTEN-nCas9-UGI	C₃- C₈	None	^[23]
Target-AID	nCas9-linker-PmCDA1-UGI	C₂ - C₅	None	^[33-34]
CDA1-BE3	PmCDA1-XTEN-nCas9-UGI	C₁ - C₇	None	^[34]
CDA1Δ-BE3	PmCDA1Δ-nCas9-UGI	C₃ - C₄	None	^[34]
A3A-BE3	hA3A-XTEN-nCas9-UGI	C₄- C₈	None	^[38⇓-40]
eA3A-BE3	hA3A（N57G）-XTEN-nCas9-UGI	C₄- C₈	TC	^[38]
A3A∆-BE3	hA3AΔ-nCas9-UGI	C₅- C₆	None	^[35]
YE1-BE3	rAPOBEC1（W90Y/R126E）-XTEN-nCas9-UGI	C₅- C₇	TC	^[46]
YE2-BE3	rAPOBEC1（W90Y/R132E）-XTEN-nCas9-UGI	C₅- C₆	TC	^[46]
YEE-BE3	rAPOBEC1（W90Y/R126E/R132E）-XTEN-nCas9-UGI	C₅- C₆	TC	^[46]
SECURE-BE3	rAPOBEC1（R33A or R33A/K34A）-XTEN-nCas9-UGI	C₅- C₇	TC	^[80]
SaBE3	rAPOBEC1-XTEN-Sa nCas9-UGI	C₃- C₁₂	TC	^[46]
dCpf1-BE	rAPOBEC1-XTEN-dCpf1-UGI	C₈- C₁₃	TC	^[54]
BE-PLUS	GCN4（10×）-nCas9 scFv-rAPOBEC1-UGI	C₄- C₁₄	TC	^[48]
TAM	dCas9-linker-hAID（P182X）	C₄- C₈	None	^[53]
CRISPR-X	dCas9/MS2-linker-hAIDΔ	C_-50- C₅₀	None	^[36]
A3G-BE3	hA3G-XTEN-nCas9-UGI	C₄- C₈	CC	^[23]
eA3G-BE	hA3G-CTD-XTEN-nCas9-2*UGI	C₄- C₈	CC	^[41-42]
ABE7.10	TadA-linker-evoTadA-linker-nCas9	A₄- A₇	None	^[11]
ABE7.10^F148A	TadA^F148A-evoTadA^F148A-linker-nCas9	A₅	None	^[47]
dCasMINI-ABE	TadA-linker-evoTadA-linker- dCasMINI	A₃- A₄	None	^[55]
CP-ABEs	TadA -linker-evoTadA -linker-CP-nCas9s	A₄- A₁₂	None	^[57]

碱基编辑器名称 Base editor	结构组成 Architecture	编辑窗口 Editing window	序列偏好 Sequence preference	参考文献 Reference
BE3	rAPOBEC1-XTEN-nCas9-UGI	C₄- C₈	TC	^[10]
AID-BE3	hAID-XTEN-nCas9-UGI	C₃- C₈	None	^[23]
Target-AID	nCas9-linker-PmCDA1-UGI	C₂ - C₅	None	^[33-34]
CDA1-BE3	PmCDA1-XTEN-nCas9-UGI	C₁ - C₇	None	^[34]
CDA1Δ-BE3	PmCDA1Δ-nCas9-UGI	C₃ - C₄	None	^[34]
A3A-BE3	hA3A-XTEN-nCas9-UGI	C₄- C₈	None	^[38⇓-40]
eA3A-BE3	hA3A（N57G）-XTEN-nCas9-UGI	C₄- C₈	TC	^[38]
A3A∆-BE3	hA3AΔ-nCas9-UGI	C₅- C₆	None	^[35]
YE1-BE3	rAPOBEC1（W90Y/R126E）-XTEN-nCas9-UGI	C₅- C₇	TC	^[46]
YE2-BE3	rAPOBEC1（W90Y/R132E）-XTEN-nCas9-UGI	C₅- C₆	TC	^[46]
YEE-BE3	rAPOBEC1（W90Y/R126E/R132E）-XTEN-nCas9-UGI	C₅- C₆	TC	^[46]
SECURE-BE3	rAPOBEC1（R33A or R33A/K34A）-XTEN-nCas9-UGI	C₅- C₇	TC	^[80]
SaBE3	rAPOBEC1-XTEN-Sa nCas9-UGI	C₃- C₁₂	TC	^[46]
dCpf1-BE	rAPOBEC1-XTEN-dCpf1-UGI	C₈- C₁₃	TC	^[54]
BE-PLUS	GCN4（10×）-nCas9 scFv-rAPOBEC1-UGI	C₄- C₁₄	TC	^[48]
TAM	dCas9-linker-hAID（P182X）	C₄- C₈	None	^[53]
CRISPR-X	dCas9/MS2-linker-hAIDΔ	C_-50- C₅₀	None	^[36]
A3G-BE3	hA3G-XTEN-nCas9-UGI	C₄- C₈	CC	^[23]
eA3G-BE	hA3G-CTD-XTEN-nCas9-2*UGI	C₄- C₈	CC	^[41-42]
ABE7.10	TadA-linker-evoTadA-linker-nCas9	A₄- A₇	None	^[11]
ABE7.10^F148A	TadA^F148A-evoTadA^F148A-linker-nCas9	A₅	None	^[47]
dCasMINI-ABE	TadA-linker-evoTadA-linker- dCasMINI	A₃- A₄	None	^[55]
CP-ABEs	TadA -linker-evoTadA -linker-CP-nCas9s	A₄- A₁₂	None	^[57]