An integrated transcriptomics and proteomics analysis reveals functional endocytic dysregulation caused by mutations...

Area of Science:

• Neuroscience
• Genetics

Background:

• Mutations in Leucine-rich repeat kinase 2 (LRRK2) are a primary genetic cause of Parkinson's disease (PD).
• Understanding the cellular functions of LRRK2 is crucial for elucidating PD mechanisms, including its role in sporadic forms of the disease.

Purpose of the Study:

• To investigate the cellular pathways affected by LRRK2 mutations.
• To identify how LRRK2 mutations contribute to the development of Parkinson's disease.

Main Methods:

• Integrated transcriptomics and proteomics analysis of induced pluripotent stem cell (iPSC)-derived dopaminergic neurons with the LRRK2-G2019S mutation.
• Validation using Western blotting, immunostaining, and functional assays (e.g., FM1-43) in iPSC-derived neurons, LRRK2 BAC transgenic rats, and post-mortem human brain tissue.

Main Results:

• Significant dysregulation of the endocytic pathway was observed in iPSC-derived dopaminergic neurons with LRRK2 mutations.
• Key endocytic proteins were downregulated, leading to impaired clathrin-mediated synaptic vesicle endocytosis.
• The endocytic pathway was also perturbed in LRRK2 BAC transgenic rats and in post-mortem brain tissue from LRRK2-G2019S patients.

Conclusions:

• LRRK2 mutations cause extensive alterations in the endocytic pathway.
• Disrupted clathrin-mediated endocytosis is implicated in LRRK2-mediated Parkinson's disease pathogenesis.