Modified ELISA for the detection of neomycin phosphotransferase II in transformed plant species

Identifying transformed plant lines carrying the antibiotic resistance marker gene, neomycin phosphotransferase II, requires a more definitive test than the ability of the plant to grow on kanamycin. Although a number of alternative assays have been described, most are cumbersome. time consuming and/or require the use of radioisotopes. This report describes an ELISA for the detection of the neomycin phosphotransferase II enzyme in transformed plant tissue. The ELISA utilises commercially available antibodies and provides a number of advantages, including an extremely low background, a reduction in the amount of tissue required for testing, and semi-quantitative data on neomycin phosphotransferase II gene expression. This method has been applied successfully to a number of independently transformed lines in nine plant species.