Fuente: WIPO "tomato" The present disclosure discloses a base editor and the use thereof. The present disclosure provides a nucleic acid base editor, specifically a base editor which is not based on CRISPR technology. The base editor comprises a sequence-specific DNA binding protein, a nickase, an exonuclease and a base-specific deaminase. This base editor is single-strand-specific, and as compared with conventional base editors, the base editor of the present disclosure has wide applicability in cells and is capable of functioning in the nucleus as well as in mitochondrial DNA and/or chloroplast DNA. This base editor has the characteristics of achieving base editing products with high purity and resulting in few indel byproducts while realizing efficient base editing, which is conducive to being used as an efficient and safe gene editing tool.