1. Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK
2. GlaxoSmithKline, Molecular Safety and Disposition, Ware, SG12 0DP, UK
3. Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK
4. MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK