1 State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, 100101 Beijing, China; University of Chinese Academy of Sciences, Beijing 100049, China.
2 State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, 100101 Beijing, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: liuf@ioz.ac.cn.