1. Department of Molecular Cell and Developmental Biology, University of California, Los Angeles, California, USA
2. Molecular Biology Institute, University of California, Los Angeles, California, USA
3. Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, California, USA
4. Department of Medicine, University of California, Los Angeles, California, USA
5. Wellcome Trust Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, UK
6. Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
7. Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge, UK
8. Department of Biological Chemistry, University of California, Los Angeles, California, USA
9. Howard Hughes Medical Institute, University of California, Los Angeles, California, USA
10. Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California, USA