1. State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China (X.-M.W., H.-P.W., H.-Z.C., D.-P.L.).
2. Medical Epigenetics Research Center, Chinese Academy of Medical Sciences, Beijing, China (H.-Z.C., D.-P.L.).
3. Haihe Laboratory of Cell Ecosystem, Tianjin, China (D.-P.L.).