Efficient exon skipping by base-editor-mediated abrogation of exonic splicing enhancers

作者：Qiu, Han; Li, Geng; Yuan, Juanjuan; Yang, Dian; Ma, Yunqing; Wang, Feng; Dai, Yi; Chang, Xing^*

来源：Cell Reports, 2023, 42(11): 113340.

DOI：10.1016/j.celrep.2023.113340

• Cytosine base editor

Duchenne muscular dystrophy (DMD) is a severe genetic disease caused by the loss of the dystrophin protein. Exon skipping is a promising strategy to treat DMD by restoring truncated dystrophin. Here, we demonstrate that base editors (e.g., targeted AID-mediated mutagenesis [TAM]) are able to efficiently induce exon skipping by disrupting functional redundant exonic splicing enhancers (ESEs). By developing an unbiased and high-throughput screening to interrogate exonic sequences, we successfully identify novel ESEs in DMD exons 51 and 53. TAM-CBE (cytidine base editor) induces near-complete skipping of the respective exons by targeting these ESEs in patients' induced pluripotent stem cell (iPSC)-derived cardiomyocytes. Combined with strategies to disrupt splice sites, we identify suitable single guide RNAs (sgRNAs) with TAM-CBE to efficiently skip most DMD hotspot exons without substantial double-stranded breaks. Our study thus expands the repertoire of potential targets for CBE-mediated exon skipping in treating DMD and other RNA mis-splicing diseases.

• 单位
  中国医学科学院北京协和医院; 中国科学院研究生院; 南方医科大学