Analysis of mitochondria recycling in a cell model of Parkinson's Disease

Abstract

Parkinson's disease (PD) is the second most common neurodegenerative disease, affecting between 1% to 3% of the population over 65 years of age and being influenced by both sporadic and genetic factors. The main neuropathological characteristic of PD is the degeneration of dopaminergic neurons in the substantia nigra and the intraneuronal accumulation of insoluble protein aggregates called Lewy bodies, formed mainly by alpha-synuclein (a-syn), which is a protein encoded by the SNCA gene in which point mutations (eg. A53T; A30P; E46K) or gene duplication are associated with the genetic form of PD. The accumulation and formation of a-syn aggregates can cause a series of results to the cells, including the malfunction of the mitochondria. Considering that mitochondria are organelles that go through continuous cycles of fission and fusion, which are essential to maintain their structure and the proper cell functions, and that interference in these processes is a possible cause for the neuronal loss characteristic of PD, this project aims to analyze how overexpression or mutations of a-syn impacts mitochondrial recycling in dopaminergic neurons derived from SH-SY5Y cells expressing wild-type (WT) or mutants (A30P or A53T) a-syn. The analysis and quantification of the fusion and fission processes will be done using the fluorescent protein MitoTimer, a molecular clock whose fluorescence changes from green to red according to the protein lifespam in the cell. Thus, the change in the color characteristic of MitoTimer will allow us to infer about mitochondrial recycling and identify impacts on this process promoted by a-syn aggregation. (AU)