CRISPR-Cas12a has both cis-and trans-cleavage activities on single-stranded DNA

• 来源期刊: 细胞研究（英文版）
• 年，卷（期）: 2018,（4）
• 页码范围: 491-493
• 页数: 3页
• 语种: 英文

摘要

Dear Editor, The CRISPR-associated protein Cas12a (previously known as Cpf1), which is an endonuclease from the type V-A CRISPR system, has been applied in both in vivo genome editing and in vitro DNA assembly.1-3 Cas12a is guided by a single CRISPR RNA (crRNA) with a T-rich protospacer adjacent motif (PAM) sequence to cleave double-stranded DNA (dsDNA) targets, generating sticky ends. Different from Cas9, Cas12a cleaves both the target and non-target strands of a targeted dsDNA by a single active site in the RuvC catalytic pocket4-6 (Supplementary information, Figure S12a). Besides, Cas12a also processes precursor crRNAs to generate mature crRNAs.7 However, the cleavage activity of Cas12a on single-stranded DNA (ssDNA) targets is less understood.