[1] Scripps Res Inst, Dept Physiol Chem, La Jolla, CA 92037 USA
[2] Whitehead Inst Biomed Res, Cambridge, MA 02142 USA
[3] MIT, Dept Biol, Cambridge, MA 02142 USA
[4] Koch Inst Integrat Canc Res, Cambridge, MA 02139 USA
[5] MIT, Howard Hughes Med Inst, Dept Biol, Cambridge, MA 02139 USA
[6] Broad Inst Harvard & Massachusetts Inst Technol, Cambridge, MA 02142 USA