PE2 Prime Editor Nuclease

Product Introduction

PE2 (Prime Editor 2) is the core component of the revolutionary prime editing system. It is a fusion protein consisting of a SpCas9(H840A) nickase and an optimized Moloney Murine Leukemia Virus reverse transcriptase (M-MLV RT), enabling precise gene editing without the need for DNA double-strand breaks. The Cas9 moiety of this protein carries the H840A point mutation, which specifically inactivates the HNH nuclease domain while retaining RuvC activity. Consequently, it cleaves only the non-target strand of DNA (the strand not complementary to the sgRNA), generating a precise single-strand nick. The fused M-MLV reverse transcriptase has been optimized through five key amino acid substitutions, significantly enhancing its thermostability, processivity, and template binding affinity.

This system can perform all 12 types of single-base substitutions, as well as the precise insertion or deletion of small DNA fragments. The entire process neither requires the generation of hazardous DNA double-strand breaks nor relies on exogenous donor DNA templates, significantly reducing the risk of off-target effects and the potential for chromosomal rearrangements. Compared to the first-generation PE1, the editing efficiency of PE2 is increased by 2.3- to 5.1-fold through protein engineering optimization of the reverse transcriptase, laying an important foundation for the widespread application of prime editing technology in basic research, gene therapy, and crop breeding.