1. Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
2. Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain
3. ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
4. Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys 23, 08010 Barcelona, Spain
5. Perelman School of Medicine, Department of Physiology, University of Pennsylvania, Clinical Research Building, 415 Curie Boulevard, Philadelphia, PA 19104, USA