Protein misfolding and aggregation to form fibrils are common features of neurodegenerative diseases, including Alzheimer's Disease, Parkinson's Disease, and related dementias such as Dementia with Lewy Bodies and Multiple System Atrophy. Drugs that reverse or block protein aggregation, combined with early diagnosis, provide the prospect for a cure that preserves the patient's memories. To design such drugs and diagnostic agents, one must understand the process of aggregation within neurons and propagation to ?infect? new neurons to identify the most relevant targets. In this funding period, we propose to use distance measurements made with fluorescence and crosslinking probes to drive computational models of the misfolding and aggregation of the proteins ?-synuclein (?S) and tau. We will model not only monomeric ?S and tau, but also aggregated forms that are not amenable to characterization by solid state NMR (ssNMR) or cryo-electron microscopy (cryo-EM). Our computational models will be used to predict the binding of small molecules in order to validate their molecular details and establish their potential for use in the design of inhibitors and diagnostic agents. Our methods can also be used to study different misfolded ?S and tau polymorphs, which exhibit different tendencies to form new fibrils and different levels of cytotoxicity. For example, recent investigations of ?S, the primary aggregator in Parkinson's Disease, have shown that tau fibrils can be seeded by some conformational forms (?strains?) of ?S fibrils, but not others. We will investigate the chemical scale differences in structure between ?S strains and the basis for tau fibril seeding by certain strains. This will shed important insight on the pathology of Parkinson's Disease, Dementia with Lewy Bodies, and Multiple System Atrophy; it will also set the stage for investigations of other secondary tau pathologies, such as A?-seeded tau aggregates in Alzheimer's Disease.

Public Health Relevance

The aggregation of proteins into neurotoxic oligomers (clusters) and ultimately into fibrillar tangles plays a pivotal role in the progression of Alzheimer's Disease, Parkinson's Disease, and related dementias. The proposed research will study the structures of these protein aggregates to gain insight into the mechanism of their aggregation and the propagation of pathology from cell-to-cell, as well as the ways in which candidate diagnostic and therapeutic molecules interact with the proteins.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS103873-01A1
Application #
9660803
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Mcgavern, Linda
Project Start
2019-02-15
Project End
2023-01-31
Budget Start
2019-02-15
Budget End
2020-01-31
Support Year
1
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104