[1] Inst Canc Res, Chester Beatty Labs, Div Struct Biol, London SW3 6JB, England
[2] Indiana Univ Sch Med, Dept Biochem & Mol Biol, Indianapolis, IN 46202 USA
[3] IGBMC, Dept Integrated Struct Biol, F-67404 Illkirch Graffenstaden, France
[4] INSERM, U964, F-67400 Paris, France
[5] CNRS, UMR7104, Illkirch Graffenstaden, France
[6] Univ Strasbourg, F-67000 Strasbourg, France
[7] UJF, European Mol Biol Lab, CNRS, Grenoble Outstn,UMI 3265, F-38042 Grenoble 9, France
[8] UJF, EMBL, CNRS, Unit Virus Host Cell Interact,UMI 3265, F-38042 Grenoble 9, France