
These included pEGFP-N1, pCAG-Cre: GFP, pUC19, pACYC177, pcDNA™3.1/myc-His A, pSPAX2, pMD2.G, pLVX-IRES-Puro, pLVX-IRES-mCherry, and pLVX-IRES-BFP. Notably, the plasmid pUC57-intein, which contains the sequences of intein, was synthesized by Beijing Tsingke Biotech Co., Ltd., China. Additionally, we used the following Addgene plasmids as generous gifts from Pawel Pelczar [21]: pCAG-NLS-HA-Dre (Addgene plasmid # 51272), pCAG-roxSTOProx-ZsGreen (Addgene plasmid # 51274), and pCAG-loxPSTOPloxP-ZsGreen (Addgene plasmid # 51269).