1. The PIGMOD Centre, Institute of Animal Physiology and Genetics, v. v. i., The Czech Academy of Sciences, 277 21 Libechov, Czech Republic
2. Department of Cell Biology, Faculty of Science, Charles University, 128 00 Prague, Czech Republic
3. Institute of Macromolecular Chemistry of the CAS, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic
4. Institute of Inorganic Chemistry of the Czech Academy of Sciences, Husinec-Řež 1001, 250 68 Řež, Czech Republic
5. Department of Ophthalmology, Justus-Liebig-University, 35392 Giessen, Germany