Enrichment of prime-edited mammalian cells with surrogate PuroR reporters.

Prime editing is a programmable genetic method that can precisely generate any desired small-scale variations in cells without requiring double-strand breaks and DNA donors. However, higher editing efficiency is greatly desirable for wide practical applications. In this study, we developed a target-specific prime editing reporter (tsPER) and a universal prime editing reporter (UPER) to facilitate rapid selection of desired edited cells through puromycin screening. The modification efficiency of HEK3 _i1CTT_d5G in HEK293T cells improved from 36.37 % to 64.84 % with the incorporation of tsPER. The target sequence of interested genes could be custom inserted into a selection cassette in tsPER to establish personalized reporters. The UPER demonstrated PE3 editing efficiency up to 74.49 % on HEK3 _i1CTT_d5G and 73.52 % on HEK3 _i1His6, achieved through co-selection with an additional pegRNA (puro) to repair the mutant Puro R cassette. Overall, tsPER and UPER robustly improved the efficiency of prime editing. Both of these approaches expand enrichment strategies for genomically modified cells and accelerate the generation of genetically modified models. [ABSTRACT FROM AUTHOR]