1. Max Planck Institute for Molecular Genetics, Ihnestr. 63-73, 14195 Berlin, Germany
2. Max Planck Institute of Colloids and Interfaces, Am Mühlberg 1, 14476 Potsdam, Germany
3. Faculty
of Biology, Chemistry and Pharmacy, Free University Berlin, Takustr.
3, 14195 Berlin, Germany
4. Charité, Institute for Medical Genetics and Human Genetics, Augustenburger Platz 1, 13353 Berlin, Germany
5. Instituto
de Fisiologı́a Celular, Universidad Nacional Autónoma de México, Circuito Exterior S/N, Ciudad
Universitaria, 04510 México D. F., México