基金Acknowledgments We thank the cell biology core facility for confocal study. The PHF8 antibody was kindly provided by Dr Jiemin Wong (East China Normal University). This work was supported by the National Basic Research Program of China (2007CB947900, 2010CB529705, 2007CB947100), the Chinese Academy of Sci- ences (KSCX2-YW-R-04, KSCX2-YW-R-I 11), the National Natural Science Foundation of China (30870538, 90919026), Postdoctoral fellowship (20090460670), and the Council of Shanghai Municipal Government for Science and Technology.