1. UPMC, University Paris 06, UMR S551, F-75013, Paris, France and, INSERM U.551, Pavillon Benjamin Delessert Hôpital de la Pitié 83, Bd de l'hôpital 75651, Paris Cedex 13, France and, GlaxoSmithKline, 25 Avenue du Quebec, 91951 Les Ulis Cedex, FranceTel.: ; Fax:
2. University of Barcelona, Department of Biochemistry & Molecular Biology, UMR S551, E-08028, Barcelona, Spain Tel.: ; Fax: