Dynasore Suppresses mTORC1 Activity and Induces Autophagy to Regulate the Clearance of Protein Aggregates in Neurodegenerative Diseases
Autophagy is an important cellular protein control process, which plays a key role in the regulation of cell homeostasis and pathogenesis of many human diseases including neurodegenerative diseases. Reduced autophagic activity and abnormal protein aggregation are common features of neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and Huntington’s disease. Therefore, pharmacological regulation of overall autophagy may be helpful for effective treatment of neurodegenerative diseases. In the present study, we find Dynasore, a potent inhibitor of dynamin, can repress the lysosomal localization of mTOR and block the activity of mTORC1, which in turn enhances the nuclear translocation of the master regulators of autophagy including TFE3 and TFEB. We find that autophagic flux is upregulated in Dynasore-treated cells. Moreover, treatment of Dynasore significantly promotes the clearance of protein aggregates formed by mutant huntingtin protein containing expanded polyglutamine (polyQ), but not damaged mitochondria. In contrast, treatment with Dynasore has no effect on the clearance of polyQ aggregates of mutant huntingtin in ATG5-depleted cells, in which autophagy is defective. Taken together, our results indicate that Dynasore affects autophagic degradation of neurodegenerative disease-associated proteins by regulating mTORC1-TFEB signaling.
KeywordsAutophagy TFEB Lysosome mTORC1 Neurodegenerative disease
This work was supported by the National Key Plan for Scientific Research and Development of China (Nos. 2017YFC0909100), the National Natural Sciences Foundation of China (Nos. 31571053 and 31771117), a Project Funded by Jiangsu Key Laboratory of Neuropsychiatric Diseases (BM2013003), and a Project Funded by the Priority Academic Program Development of the Jiangsu Higher Education Institutes (PAPD).
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Conflict of Interest
The authors declare that they have no conflict of interest.
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