1 Department of Molecular Biology and Genetics - Afgrødegenetik og Bioteknologi, Department of Molecular Biology and Genetics, Science and Technology, Aarhus University2 Department of Molecular Biology and Genetics - Afgrødegenetik og Bioteknologi, Department of Molecular Biology and Genetics, Science and Technology, Aarhus University
Genetic transformation is currently met with substantial scepticism among the general public. One major concern is the mingling of genetic material between species. We have initiated a collaborating project with different groups from University of Copenhagen, the Danish Agricultural Advisory Service and Sejet Plant Breeding based on the Cisgenesis concept. Cisgenesis implies that the plants are transformed only with its own or very closely related genetic material and that the final Cisgenic plants have to be free of any foreign genes. The Cisgenesis concept allows for the introduction of extra gene copies of a particular gene whereby a particular trait can be accentuated. Transgenic crops generated by the Cisgenesis concept are accordingly very similar to those generated by conventional breeding. In our part of the project we are focusing on barley phytases as candidate genes for Cisgenesis. Recently, Dionisio et al. (2011) have cloned and characterized phytases belonging to the purple acid phosphatases (PAPs) in barley. We have isolated the genomic PAP-clone of the isoform expressed during grain filling including 2.3 kb of the promoter region and 600 bp of the terminator region using a genomic barley lambda library. The clone has been inserted into a Cisgenic Agrobacterium vector where both the gene of interest and the selection gene are flanked by their own T-DNA borders in order to promote integration of the two genes at unlinked places in the plant genome. T0-plants show increases in the phytase activity of mature seeds from 1350 in wild type to 7500 FTU/kg in T0-plants. We have identified two Cisgenic T1-lines without selection gene and vector backbone but with one additional genomic clone of the phytase gene. Lines homozygous for the additional cisgene show 2-3 fold increases in phytase activity. The integration pattern of the cisgenes are currently investigated.