 | Laura Hagens Rowan University BiochemistryMentor(s)David S. Talaga, Ph.D. Jason T. Giurleo, Ph.D. Department of Chemistry and Chemical Biology Rutgers University |
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| Studying the conformational changes in α-synuclein that lead to aggregation and onset of Parkinson’s disease using cy3b dye | ||
| 1% of Americans are diagnosed with Parkinson’s disease by the age of 65 and 4% by the age of 85. A leading cause of this disease is believed to be the aggregation of α-synuclein (α--syn) in brain cells. It is known that α--syn undergoes a conformational change from natively unfolded monomers to high ordered cross-beta amyloid fibrils. This occurs through a process that is referred to as amyloidogenesis. However, the mechanism of the aggregation is not well understood. Understanding this mechanism has the potential to lead to new therapeutic targets that can help not just Parkinson’s patients, but also those suffering from over 20 other amyloid-related diseases such as Alzheimer’s and Type II Diabetes. A19C, α--Syn mutant, was labeled with the extrinsic fluorophore Cy3b. Time-correlated single photon counting (TCSPC) was used to measure the fluorescence lifetime of Cy3b as a way to monitor the conformational changes of the host protein via Cy3b’s interaction with one or more of the four available tyrosine residues. We have tested the labeling scheme by exposing the protein to sodium dodecyl sulfate (SDS), which is known to induce an alpha-helical secondary structure, and by incubation with polytetrafluoroethylene (PTFE) balls, which are known to induce cross-beta structure. Preliminary results indicate that Cy3b’s fluorescence lifetime is only slightly modulated by these conditions. Though not conformationally sensitive, Cy3b still has potential use as a Förster Resonance Energy Transfer (FRET) donor. |