MTOR and Parkinson disease: Autophagy is a crucial homeostatic response of DA cells to neurochemical intoxication and its pharmacological induction with rapamycin protects cellular and animal models of PD.8, 9 To investigate the effects of Hb overexpression, we monitored the phosphorylation status of the eukaryotic initiation factor 4E binding protein 1 (4E-BP1), a direct target of mTOR,22 showing that in Hb cells the phosphorylation of 4E-BP1 was stable while reduced in control cells, as expected (Figure 4b).