Genetic Stability and Expression of Foreign Genes in Transgenic Lines of the Legume Vicia narbonensis
We have transformed the grain legume Vicia narbonensis via Agrobacterium-mediated gene transfer and regenerated fertile plants carrying the T-DNA of the construct pGV3850Hygro which confers the characters hygromycin resistance and nopalin production. Initial transformants harbouring a single copy integration of the T-DNA were identified and the progeny of three such clones was analysed in detail. The transgene was inherited in the first generation according to Mendelian laws as shown by biochemical and Southern analyses. Through self pollinations homozygous as well as hemizygous sublines were obtained and further characterized. In order to follow the transmission of the two foreign genes for the hygromycin phosphotransferase (hph) and the nopalin synthase (nos) for a long period, biochemical and molecular analyses were performed up to the fifth generation.The genetic stability as well as the stable expression of both characters was demonstrated for homozygous sublines and their progenies. For the hemizygous sublines sometimes unexpected results were obtained, indicating that in some cases genetic instability and/or modification of parts of the integrated foreign DNA might have occurred within the hemizygous offspring.
KeywordsTransgenic Line Foreign Gene Genetic Stability Hygromycin Resistance Junction Fragment
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