Arianna De Toni1*
, Marie Zbinden2*
, Jonathan A Epstein3
, Ariel Ruiz i Altaba2
, Alain Prochiantz1,4
and Isabelle Caillé1,5 
1
UMR CNRS 8542, ENS, rue d'Ulm, 75005 Paris, France
2
University of Geneva Medical School, 8542 CMU, rue Michel Servet, CH-1211 Geneva 4, Switzerland
3
Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Curie Boulevard, Philadelphia, Pennsylvania 19104, USA
4
Collège de France, place Marcelin Berthelot, 75231 Paris Cedex 05, France
5
UFR de Biologie, Université Denis Diderot, 75013 Paris, France