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Beyond the SNARE: Munc18-1 chaperones α-synuclein
Mugdha Deshpande1, Avital A Rodal2
1Department of Biology, Brandeis University, Waltham, MA 02453.
The Journal of Cell Biology
|September 7, 2016
Summary
Mutations in MUNC18-1 linked to early infantile epileptic encephalopathy (EIEE) cause protein misfolding. These Munc18-1 mutants also promote the aggregation of alpha-synuclein, a key protein implicated in neurodegenerative diseases.
Area of Science:
- Molecular biology
- Neuroscience
- Genetics
Background:
- Early infantile epileptic encephalopathy (EIEE) is a severe neurological disorder.
- Mutations in the MUNC18-1 gene are associated with EIEE, leading to Munc18-1 protein misfolding and aggregation.
- Alpha-synuclein aggregation is a hallmark of several neurodegenerative diseases, including Parkinson's disease.
Purpose of the Study:
- To investigate the role of Munc18-1 in the context of EIEE-associated mutations.
- To determine if Munc18-1 acts as a molecular chaperone for alpha-synuclein.
- To explore the impact of aggregated Munc18-1 mutants on alpha-synuclein aggregation.
Main Methods:
- Analysis of Munc18-1 protein folding and aggregation in cells with EIEE-associated mutations.
- Biochemical assays to assess the interaction between Munc18-1 and alpha-synuclein.
- Cellular models to observe the effect of Munc18-1 mutants on alpha-synuclein aggregation.
Main Results:
- EIEE-associated mutations induce Munc18-1 misfolding and aggregation.
- Munc18-1 functions as a molecular chaperone for alpha-synuclein.
- Aggregated Munc18-1 mutants significantly promote the aggregation of alpha-synuclein.
Conclusions:
- Munc18-1 plays a critical role in maintaining alpha-synuclein homeostasis.
- Misfolded Munc18-1, particularly in the context of EIEE, can exacerbate alpha-synuclein pathology.
- These findings link EIEE pathogenesis to mechanisms underlying other synucleinopathies.
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