Puromycin is an aminonucleoside antibiotic, derived from Streptomyces alboniger, which acts as a protein synthesis inhibitor. It binds to the target ribosome site A, where it is transferred to the growing polypeptide chain causing premature chain termination (Lührmann et al.; Rodriguez-Fonseca et al.; Azzam & Algranati). A biologically inactive form is generated when puromycin is N-acetylated by puromycin-N-acetyltransferase, allowing this gene to be used as a selective resistance marker (Vara et al. 1985).CELL LINE DEVELOPMENT· Selects for cells expressing puromycin-N-acetyltransferase resistance gene as a research tool (de la Luna & Ortín; Iwaki et al.).· Useful in CRISPR/Cas9 mammalian gene editing by selecting for successful Cas9-induced knock-in with puromycin resistance gene (Park et al.). CANCER RESEARCH· Possesses anti-tumor activity when tested against numerous cell lines (Foley & Eagle).