Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France Competing interests The authors declare that no competing interests exist. Marta Tormos-Pérez Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France Competing interests The authors declare that no competing interests exist. Sabine Vaur Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France Competing interests The authors declare that no competing interests exist. Amélie Feytout Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France Competing interests The authors declare that no competing interests exist. Julien Jaegy Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France Competing interests The authors declare that no competing interests exist. Dácil Alonso Gil Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France Competing interests The authors declare that no competing interests exist. Stéphanie Vazquez Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France Competing interests The authors declare that no competing interests exist. Karl Ekwall Department of Biosciences and Nutrition, Karolinska Institute, Stockholm, Sweden Competing interests The authors declare that no competing interests exist. Jean-Paul Javerzat Institut de Biochimie et Génétique Cellulaires, CNRS-Université de Bordeaux, Bordeaux, France For correspondence