1. Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, United States
2. Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università Federico II, Via S Pansini 5, 80131 Naples, Italy
3. Istituto di Endocrinologia e Oncologia Sperimentale del CNR, Via S Pansini 5, 80131 Naples, Italy
4. Signaling and Structural Biology Laboratory, The Francis Crick Institute, London NW1 1AT, U.K.
5. Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, Malet Street, London WC1E 7HX, U.K.