Cover illustration

Cover image: Neuronal inactivation of the PINK1 gene, which has been implicated in the development of Parkinson's disease, caused degeneration of dopaminergic and retinal neurons (black spots) in a Drosophila model of this disease. Transgenic expression of human PINK1 or treatment of PINK1-inactivated flies with antioxidants (e.g., vitamin E) prevented this degeneration. Light microscopic images (×25 magnification) of the external compound eye of Drosophila fruit flies at 1 day (top four images) or 7 days (bottom two images) of age are shown: wild-type control (Top Left), dPINK1-RNAi (Top Right), rescue of the mutant phenotype by hPINK1 (Middle Left), no rescue by hPINK1G309D mutant (Middle Right), dPINK1-RNAi (Bottom Left), and rescue by dietary supply of vitamin E (Bottom Right). See the article by Wang et al. on pages 13520–13525.