TOMM20 and neurodegenerative disease: The Drosophila compound eye is a powerful system to study the pathogenesis of neurodegenerative diseases.28 We next expressed GFP-tagged TOM20-PINK1 proteins in the fly compound eyes using the GMR (Glass Multiple Reporter) promoter and found that both GMR-tom20-pink1-GFP and GMR-tom20-pink1KD-GFP flies had truncated PINK1 expressed and normal eye morphology (Figure 1c).