1 CAS-MPG Partner Institute for Comp. Biology, 320 Yue Yang Road, 200031 Shanghai, China, 2Max Planck Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Golm, 3Ernst-Moritz-Arndt-University of Greifswald, Competence Center for Functional Genomics, F.L.Jahnstraße 15, 17487, Greifswald and 4University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany (At 2007-03-07)