1. CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of Microbiology, Chinese Academy of Sciences 100101 Beijing P. R. China
2. University of Chinese Academy of Sciences Beijing 100049 P. R. China
3. Max Planck Institute for Evolutionary Biology 24306 Plön Germany
4. State Key Laboratory of Membrane Biology Institute of Zoology Chinese Academy of Sciences 100101 Beijing P. R. China
5. Institute for Stem Cell and Regeneration Chinese Academy of Sciences 100101 Beijing P. R. China
6. Beijing Institute for Stem Cell and Regenerative Medicine 100101 Beijing P. R. China