[1] Univ Cologne, Inst Genet, D-50931 Cologne, Germany
[2] Univ Cologne, Cologne Excellence Cluster Cellular Stress Respon, D-50931 Cologne, Germany
[3] Univ Cologne, Ctr Mol Med, D-50931 Cologne, Germany
[4] Univ Calif Davis, Dept Mol & Cellular Biol, Davis, CA 95616 USA
[5] Univ Bordeaux Segalen, Inst Biochim & Genet Cellulaires, CNRS, UMR5095, F-33077 Bordeaux, France