PhD thesis at Georg-August University Göttingen, Department of Plant Physiology, in the group of Christiane Gatz ; Postdoc at the Michigan State University (Lansing), Department for Biochemistry and Molecular Biology, in the group of Gregg Howe ; Postdoc at the Freie Universitaet Berlin, Department of Plant Biochemistry, in the group of Tina Romeis ; Postdoc at the Leibniz Universitaet Hannover, Institute for Plant Nutrition, Department of Molecular Nutrition and Biochemistry of Plants