1. Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA 90095, USA
2. Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA
3. Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
4. Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA