Expression of a chimeric nitrate reductase gene in transgenic lettuce reduces nitrate in leaves

• Published in: Plant cell reports Vol. 18; no. 11; pp. 889 - 896
• Main Authors: Curtis, I.S, Power, J.B, Laat, A.M.M. de, Caboche, M, Davey, M.R
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.08.1999; Springer Nature B.V; Springer Verlag
• Subjects: Agrobacterium tumefaciens; Biological and medical sciences; Biotechnology; cotyledons; cultivars; DNA; enzyme activity; Fundamental and applied biological sciences. Psychology; gene expression; genes; Genetic engineering; Genetic technics; Genetics; hybridization; kanamycin; kanamycin sulfate; kinases; Lactuca sativa; leaves; Lettuce; Life Sciences; Methods. Procedures. Technologies; neomycin phosphotransferase II; nia gene; nitrate reductase; nitrates; nitrogen content; nptII gene; Plants genetics; plasmid vectors; promoter regions; Transgenic animals and transgenic plants; Transgenic plants; Enzyme; Agrobacterium tumefaciens; Plant leaf; Nitrates; Compositae; Gene expression; Enzymatic activity; Vegetable crop; Nitrate reductase; Dicotyledones; Angiospermae; Bacteria; Spermatophyta; Transgenic plant; Oxidoreductases; Rhizobiaceae; Lactuca sativa; DNA
• ISSN: 0721-7714; 1432-203X
• DOI: 10.1007/s002990050680

Transgenic plants of four glasshouse-grown lettuce cultivars ('Cortina', 'Evola', 'Flora' and 'Luxor') were obtained by co-cultivating excised cotyledons with Agrobacterium tumefaciens. The Agrobacterium strain LBA4404 contained the binary vector pBCSL16, which carried a nitrate reductase (nia) cDNA linked to CaMV promoter and terminator sequences, and the neomycin phosphotransferase II (nptII) gene. Transformed shoots were selected by their ability to root on medium containing kanamycin sulphate by a positive NPTII assay and by PCR analysis. The presence of the nia cDNA in transgenic lettuce was confirmed by nitrate reductase (NR) enzymatic assay, a reduction in the nitrate content of leaves and by Southern hybridisation. PCR analysis of cDNA fragments from transgenic plants confirmed that both nia and nptII genes were expressed in first seed-generation (T1) lettuce plants. The commercial importance of reduced nitrate concentrations in lettuce is discussed.