1. Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, Scotland, UK
2. Institute of Medical Sciences, University of Aberdeen, Aberdeen, Scotland, UK
3. Key laboratory of Systems Biology, Shanghai Institute of Biological Sciences, Chinese Academy of Sciences, Shanghai, China
4. Chinese Academy of Sciences Key Laboratory of Computational Biology, Chinese Academy of Sciences, Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
5. State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang, Beijing, China
6. Department of Pathology and Department of Biology, University of Washington, Seattle, WA, USA