1. Leibniz Universität Hannover, Department of Molecular Nutrition and Biochemistry of Plants, 30419 Hannover, Germany
2. Leibniz Universität Hannover, Institute of Plant Genetics, 30419 Hannover, Germany
3. Research Core Unit Electron Microscopy, Hannover Medical School (MHH), 30625 Hannover, Germany
4. Max-Planck-Institute for Biology of Aging, 50931 Köln, Germany