1. Bioinformatics, Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany
2. Systems Biology and Mathematical Modeling, Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam, Germany
3. Mathematics Department, University of Tampa, Tampa, FL 33606, USA
4. Bioinformatic Department, Centre of Plant Systems Biology and Biotechnology (CPSBB), 4000 Plovdiv, Bulgaria