1. Protein Phosphorylation Laboratory, London Research Institute, Cancer Research UK, 44 Lincoln's Inn Fields, London WC2A 3LY, U.K.
2. Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, U.K.
3. Cell Biophysics Laboratory, London Research Institute, Cancer Research UK, 44 Lincoln's Inn Fields, London WC2A 3LY, U.K.
4. Division of Cancer Studies, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, U.K.
5. Structural Biology Laboratory, London Research Institute, Cancer Research UK, 44 Lincoln's Inn Fields, London WC2A 3LY, U.K.
6. Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, Malet Street, London WC1E 7HX, U.K.