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08:55
Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag
Published on: December 14, 2017
LRRK2 controls an EndoA phosphorylation cycle in synaptic endocytosis
Samer Matta1, Kristof Van Kolen, Raquel da Cunha
1VIB Center for the Biology of Disease, 3000 Leuven, Belgium.
Neuron
|September 25, 2012
Summary
Parkinson's disease protein LRRK2 regulates synaptic endocytosis by phosphorylating EndophilinA (EndoA). Both too much and too little LRRK2 activity disrupt this process, impacting synaptic vesicle formation.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Leucine-rich repeat kinase 2 (LRRK2) is a key protein implicated in Parkinson's disease pathogenesis.
- The precise mechanisms by which LRRK2 influences synaptic function, particularly endocytosis, remain incompletely understood.
Purpose of the Study:
- To elucidate the role of LRRK2 in regulating synaptic endocytosis.
- To identify LRRK2's direct targets and their functional consequences at the synapse.
Main Methods:
- Utilized genetic studies with Lrrk loss-of-function mutants and Parkinson's disease-associated LRRK2(G2019S) variants.
- Performed biochemical analyses, including in vitro and in vivo assays.
- Investigated synaptic vesicle endocytosis at Drosophila neuromuscular junctions.
Main Results:
- Identified EndophilinA (EndoA) as a critical LRRK2 regulator.
- Demonstrated that LRRK2 phosphorylates EndoA at serine 75 (S75) within its BAR domain.
- Showed LRRK2-mediated EndoA phosphorylation impacts membrane tubulation, membrane association, and synaptic vesicle endocytosis.
Conclusions:
- LRRK2 kinase activity modulates EndoA membrane association; reduced activity facilitates it, while increased activity inhibits it.
- Dysregulated LRRK2 kinase activity, leading to either excessive or insufficient EndoA phosphorylation, impairs synaptic endocytosis.
- Proposed a model where LRRK2 kinase activity is integral to an EndoA phosphorylation cycle essential for efficient synaptic vesicle formation.
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