1. BIOC, CNRS, Ecole polytechnique, Institut Polytechnique de Paris, F-91128 Palaiseau, France
2. RNA Molecular Biology, ULB Cancer Research Center (U-CRC), Fonds de la Recherche Scientifique (F.R.S./FNRS), Université Libre de Bruxelles, B-6041 Charleroi-Gosselies, Belgium
3. Department of Pharmacology, Weill Medical College, Cornell University, NY 10065, New York, USA
4. Department of Molecular Biology, University Medical Center Göttingen, 37073 Göttingen, Germany