Leucine-rich repeat kinase 2 disturbs mitochondrial dynamics via Dynamin-like protein

Area of Science:

• Neuroscience
• Genetics
• Cell Biology

Background:

• Mutations in Leucine-rich repeat kinase 2 (LRRK2) are a primary genetic cause of Parkinson's disease (PD).
• Mitochondrial dysfunction is implicated in both sporadic and familial forms of PD.
• The precise mechanisms linking LRRK2 mutations to neurodegeneration are not fully understood.

Purpose of the Study:

• To investigate the impact of the pathogenic LRRK2 G2019S mutation on mitochondrial morphology and dynamics in cortical neurons.
• To explore the interaction between LRRK2 and Dynamin like protein 1 (DLP1) in the context of mitochondrial fission.

Main Methods:

• Utilized cortical neurons to study the effects of LRRK2 G2019S expression.
• Investigated the interaction and co-localization of endogenous LRRK2 and DLP1.
• Examined the role of DLP1 in LRRK2-induced mitochondrial fission using knockdown techniques.
• Assessed reactive oxygen species (ROS) levels in cells expressing LRRK2.

Main Results:

• LRRK2 G2019S expression induced defects in mitochondrial morphology and dynamics.
• Endogenous LRRK2 interacts with and co-localizes with DLP1, a key mitochondrial fission factor.
• LRRK2 expression promoted DLP1 translocation to mitochondria, driving mitochondrial fission.
• Knockdown of DLP1 inhibited LRRK2-induced mitochondrial fission, and co-expression induced mitochondrial clearance.
• LRRK2 expression led to increased cellular reactive oxygen species levels.

Conclusions:

• LRRK2 G2019S disrupts mitochondrial fission/fusion dynamics, contributing to neuronal dysfunction in Parkinson's disease.
• The interaction between LRRK2 and DLP1 is crucial for LRRK2-mediated mitochondrial alterations.
• These findings offer insights into the pathobiology of LRRK2 in Parkinson's disease and suggest potential therapeutic targets.