Targeted degradation of α-synuclein by arginine-based PROTACs

Area of Science:

• Neuroscience
• Biochemistry
• Drug Discovery

Background:

• Parkinson's disease (PD) is a prevalent neurodegenerative disorder linked to alpha-synuclein (α-syn) aggregation.
• Current treatments for PD face challenges in inhibiting or reducing α-syn accumulation.
• Targeted Protein Degradation (TPD) offers a new strategy for disease treatment by degrading specific proteins.

Purpose of the Study:

• To develop and evaluate Proteolysis Targeting Chimeras (PROTACs) for targeted degradation of α-syn.
• To investigate the efficacy of arginine-based PROTACs in reducing α-syn and its aggregates.
• To identify the E3 ligase involved in PROTAC-mediated α-syn degradation.

Main Methods:

• Development of PROTACs utilizing arginine as the E3 ligase ligand and a benzothiazole-aniline variant as the α-syn warhead.
• Testing PROTAC efficacy in degrading α-syn and its aggregates in mammalian cells and Caenorhabditis elegans (C. elegans) models.
• Identification of UBR1 as the responsible ubiquitin E3 ligase.

Main Results:

• The PROTAC Arg-PEG1-T^α-syn demonstrated significant degradation of both wild-type and mutant α-syn (A53T) in mammalian cells.
• Arg-PEG1-T^α-syn effectively reduced α-syn aggregates and associated toxicities in both cellular and C. elegans models.
• UBR1 was confirmed as the E3 ligase mediating the PROTAC's degradation activity.

Conclusions:

• Arginine-based PROTACs represent a viable strategy for targeting α-syn degradation.
• This approach shows promise for developing novel therapeutics for Parkinson's disease and other synucleinopathies.
• The study highlights the potential of single amino acid-based PROTACs in neurodegenerative disease treatment.