Rui Liu1, Kazuyuki Aihara2, Luonan Chen3. 1. School of Mathematics, South China University of Technology, Guangzhou 510640, China; Pazhou Lab, Guangzhou 510330, China. Electronic address: scliurui@scut.edu.cn. 2. International Research Center for Neurointelligence, The University of Tokyo, Tokyo 113-8654, Japan; Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan. Electronic address: kaihara@g.ecc.u-tokyo.ac.jp. 3. State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China; Key Laboratory of Systems Health Science of Zhejiang Province, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310024, China. Electronic address: lnchen@sibs.ac.cn.