A growth-factor-activated lysosomal K+ channel regulates Parkinson's pathology

Lysosomes have fundamental physiological roles and have previously been implicated in Parkinsons disease(1-5). However, how extracellular growth factors communicate with intracellular organelles to control lysosomal function is not well understood. Here we report a lysosomal K+ channel complex that is activated by growth factors and gated by protein kinase B (AKT) that we term lysoK(GF.) LysoK(GF) consists of a pore-forming protein TMEM175 and AKT: TMEM175 is opened by conformational changes in, but not the catalytic activity of, AKT. The minor allele at rs34311866, a common variant in TMEM175, is associated with an increased risk of developing Parkinsons disease and reduces channel currents. Reduction in lysoK(GF) function predisposes neurons to stress-induced damage and accelerates the accumulation of pathological alpha-synuclein. By contrast, the minor allele at rs3488217another common variant of TMEM175, which is associated with a decreased risk of developing Parkinsons diseaseproduces a gain-of-function in lysoK(GF) during cell starvation, and enables neuronal resistance to damage. Deficiency in TMEM175 leads to a loss of dopaminergic neurons and impairment in motor function in mice, and a TMEM175 loss-of-function variant is nominally associated with accelerated rates of cognitive and motor decline in humans with Parkinsons disease. Together, our studies uncover a pathway by which extracellular growth factors regulate intracellular organelle function, and establish a targetable mechanism by which common variants of TMEM175 confer risk for Parkinsons disease.

Automated summary

This study uncovers a pathway by which extracellular growth factors regulate intracellular organelle function, and establishes a targetable mechanism by which common variants of TMEM175 confer risk for Parkinson's disease. The TMEM175 gene's common variants can increase or decrease the risk of developing Parkinson's disease, affecting neuronal damage and defense capabilities.