Mol. Cells

Targeted Base Editing via RNA-Guided Cytidine Deaminases in Xenopus laevis Embryos

Dong-Seok Park, Mijung Yoon, Jiyeon Kweon, An-Hee Jang, Yongsub Kim, and Sun-Cheol Choi

Additional article information

Abstract

Genome editing using programmable nucleases such as CRISPR/Cas9 or Cpf1 has emerged as powerful tools for gene knock-out or knock-in in various organisms. While most genetic diseases are caused by point mutations, these genome-editing approaches are inefficient in inducing single-nucleotide substitutions. Recently, Cas9-linked cytidine deaminases, named base editors (BEs), have been shown to convert cytidine to uridine efficiently, leading to targeted single-base pair substitutions in human cells and organisms. Here, we first report on the generation of Xenopus laevis mutants with targeted single-base pair substitutions using this RNA-guided programmable deaminase. Injection of base editor 3 (BE3) ribonucleoprotein targeting the tyrosinase (tyr) gene in early embryos can induce site-specific base conversions with the rates of up to 20.5%, resulting in oculocutaneous albinism phenotypes without off-target mutations. We further test this base-editing system by targeting the tp53 gene with the result that the expected single-base pair substitutions are observed at the target site. Collectively, these data establish that the programmable deaminases are efficient tools for creating targeted point mutations for human disease modeling in Xenopus.

Keywords: base editing, CRISPR/Cas9, genome engineering, Xenopus laevis

Supplementary data

Article information

Mol. Cells.Nov 30, 2017; 40(11): 823-827.
Published online 2017-11-20. doi:  10.14348/molcells.2017.0262
1Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 05505, Korea
*Correspondence: yongsub1.kim@gmail.com (YK); choisc@amc.seoul.kr (SCC)
Received October 17, 2017; Accepted November 6, 2017.
Articles from Mol. Cells are provided here courtesy of Mol. Cells

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