1. Department of Biosciences, University of Milan, 20133 Milan, Italy (M.C.B., G.L., A.C.);
2. Department of Biology (G.L.) and
3. Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, 48149 Münster, Germany (S.B., J.K.); and
4. Department of Biomedical Sciences (A.W.), University of Padua, 35131 Padova, Italy;
5. Institute of Biophysics, Consiglio Nazionale delle Ricerche, 20133 Milan, Italy (A.C.)