nptII gene as part of a bifunctional marker gene

US 5639663 EP 583258 B1
Title Bifunctional genetic markers
Application No. & Filing date No. 122520
January 21, 1994
EP 92907796.4
March 30, 1992
Issue date June 17, 1997* August 19, 1998**
Language English English (Claims in English, German and French)
Remarks *The patent term is 17 years from the date of issuance. **The patent term is 20 years from the date of filing the application.

The National Research Council of Canada has two granted patents, in the United States and in Europe, directed to dual genetic markers composed of fused genes, which provide a reporter marker gene (glucuronidase (gusA) gene) and an antibiotic resistance gene (nptII gene).

The gusA gene encodes ß-glucuronidase (GUS), a hydrolase that cleaves a wide variety of ß-glucuronides. GUS is the most widely used reporter system for plants. It is easy to quantify, highly sensitive and very specific. Substrates for GUS are available for spectrometric, fluorometric and histochemical detection assays.

The bifunctional genetic marker of the invention allows for genetic selection of the transformed cells (npt II gene) and subsequent spatial localization and quantitative estimation of gene activity (gus gene).

The invention is limited with respect to the components of the fusion marker. However, the host organism expressing the marker is not limited to any organism in particular. It could potentially be any host as long as it is capable of expressing the stable polypeptide having both activities.