1. Merck Research
Laboratories, 2015 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
2. Whitehead Institute
for Biomedical Research, 9 Cambridge
Center, Cambridge, Massachusetts 02142, United States
3. Howard
Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
4. Banting and
Best Department of Medical Research, Terrance Donnally Centre of Cellular
and Biomedical Research, University of Toronto, Toronto, Ontario, Canada
5. Fundación
Centro de Excelencia en Investigación de Medicamentos Innovadores
en Andalucı́a, Medina, Parque Tecnológico de Ciencias de la Salud , Avenida Conocimiento 34, 18016 Grenada, Spain