1. Bioinformatics and Mathematical Modeling Center of Plant Systems Biology and Biotechnology Plovdiv 4000 Bulgaria
2. Systems Biology and Mathematical Modeling Max Planck Institute of Molecular Plant Physiology Potsdam 14476 Germany
3. Bioinformatics, Institute of Biochemistry and Biology University of Potsdam Potsdam 14476 Germany
4. Organismal and Evolutionary Research Programme, Faculty of Biological and Environmental Sciences University of Helsinki Helsinki 00014 Finland