TUBB3 and Parkinson disease: Having established that 30 μM levodopa exacerbates ΔΨM loss and may stabilize beta III tubulin in the context of parkinsonism, we then examined lysosomes because mitochondrial impairment plays a strong role in inducing lysosome biogenesis [54] and microtubules are critical for lysosome motility [55], but also because impairment of lysosome function is strongly implicated in PD [56].