Functional proteomics of mutant LRRK2 induced Parkinson's Disease

• Applicants: Professor Dr. Thomas Gasser; Professor Dr. Jared Sterneckert
• Subject Area: Molecular and Cellular Neurology and Neuropathology
• Term: from 2013 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 234087398

LRRK2 mutations are the most common genetic cause of PD. Patients carrying this mutation almost always harbor Lewy bodies, which are primarily composed of alpha-synuclein (aSYN). To better understand the mechanistic link between mutant LRRK2 and PD pathology, we have previously developed an in vitro model of PD pathogenesis using patient-derived induced pluripotent stem cells iPSCs harboring different LRRK2 mutations, and then specifically induced gene-correction of the mutant LRRK2 allele. Preliminary work with these lines demonstrates that iPSC-derived cultures of midbrain dopaminergic (mDA) neurons harboring mutant LRRK2 have increased levels of aSYN and TAU. Here, we propose to expand upon these results by generating a library of iPSCs from a variety of genetic backgrounds with specific genetic modifications as well as isogenic controls using our previously demonstrated gene-targeting technology. Each of these iPSC lines will be analyzed for PD-relevant phenotypes (aSYN and TAU processing, vesicle dynamics, and cytoskeletal aberrations) using protocols that have been previously established and validated. Further, we propose to use state-of-the-art proteomics technologies to assess the effects of each of these variants upon the phospho-proteome and identify LRRK2 phosphorylation targets specifically induced by PD-associated mutations. We will use the above-described assays in combination with siRNA and overexpression to test if the proposed targets of LRRK2 are necessary and/or sufficient for the expression of PD-related phenotypes.

• DFG Programme: Research Grants