1. Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
2. Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois 60637, United States
3. Department of Genetics, Stanford University, Stanford, California 94305, United States
4. Department of Chemistry, University of Cambridge, Cambridge CB2 0SP, U.K.
5. Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China