G-418 (Geneticin), as an aminoglycoside antibiotic, is a mainstream resistance reagent used for stable transfection screening in molecular genetics experiments. Its mechanism of action is to interfere with the function of the 80S ribosome, thereby inhibiting protein synthesis in eukaryotic cells. It is widely used in selective culture of mammalian, plant, and yeast cells. This antibiotic is toxic to bacteria, fungi, higher plants, mammalian cells, protozoa, and worms. Its dominant resistance genes are located on Tn601 (903) and Tn5 transposons. The gene derived from this bacterium can be effectively expressed in eukaryotic cells, endowing the host with G-418 resistance and enabling it to survive in drug containing culture medium. With this characteristic, G-418 has become a commonly used tool in gene transfer, gene knockout, resistance screening, and transgenic animal research.