Group Leader: PD Dr. Renate Schmidt
The impact of duplications in the oilseed rape genome
Polyploidy is widespread in the plant kingdom. We are therefore interested to trace the fate of duplicated regions in the course of evolution. We use the allopolyploid species Brassica napus (oilseed rape) to study the arrangement, structure and expression of duplicated genes in selected regions of the rapeseed genome. A PCR-based screening platform of an oilseed rape BAC library enables quick access to regions of interest in the rapeseed genome. Furthermore, we determine the allelic diversity of selected genes in a broad set of oilseed rape accessions.
Genetic analysis of seed traits in Arabidopsis thaliana
We use the natural occurring variation in Arabidopsis thaliana accessions to study the genetic factors of importance for the trait seed yield. We determine characters such as seed weight, seed size, seed number per silique and seed yield per plant in a population of recombinant inbred lines and in a broad set of Arabidopsis thaliana accessions. QTL mapping and association studies are used to identify loci of importance for these traits.
Transgene silencing in Arabidopsis thaliana
Silencing of introduced genes is often observed in transgenic plants. A systematic analysis of transgene expression in Arabidopsis thaliana showed that transgene silencing is triggered by excessive transcript levels. The transgene expression level correlates with the probability that silencing is initiated early in plant development. The study of progeny of plants with silenced transgenes showed that the silenced state is not transmitted to the next generation, instead silencing has to be established in each generation anew. We are studying now how different environmental factors and genetic backgrounds affect the onset and/or the spread of silencing.