[1] Univ Lausanne, Fac Biol & Med, Dept Biol Cellulaire & Morphol, Lausanne, Switzerland
[2] Univ Geneva, Ecole Med, Dept Physiol Cellulaire & Metab, Geneva, Switzerland
[3] INSERM, U561, Paris, France
[4] Univ Paris N, Hop Cochin St Vincent de Paul, Paris, France