Exploring Amyloid-B Aggregation Pathways and Identifying Key Differences Between AB40, AB42, and Known Mutants

Date
2021-12-03
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract

First described in 1906 by Alois Alzheimer, who reported the presence of senile plaques and neurofibrillary tangles in the brain tissue of a sufferer, Alzheimer’s disease is now the most common form of dementia. Many years later it was determined that the hallmark senile plaques were composed of aggregated peptide fragments, referred to as amyloid beta. Like other amyloids, these fragments can exist as highly disordered monomers, disordered soluble oligomers, and highly ordered macroscopic fibrils. Despite decades of research, many open questions remain in regard to the role of amyloid beta in the pathology of Alzheimer’s disease. In this dissertation, molecular dynamics simulations, in complement with experimental results, will be employed to address a few of these questions. In particular, a molecular level picture is developed elucidating the differences in aggregation rates between the two most common isoforms of the protein, providing evidence of possible pharmaceutical targets. Data related to the conformational search undertaken by amyloid beta monomers will be analyzed, revealing a possible connection between the secondary structure of wild type and mutated monomers and their observed fibrilization rates. Finally, the fibril elongation behavior of amyloid beta containing a single-point mutation associated with a devastating form of Alzheimer’s disease will be investigated to gain insight into the physicochemical properties driving its distinct clinical presentations. The resulting conclusions of these efforts lay the foundation for further experiments which could address critical factors related to the pathological role of aggregation rates, different early oligomerization behavior, and sources of neurotoxicity.

Description
Degree
Doctor of Philosophy
Type
Thesis
Keywords
amyloid-beta, aggregation, amyloid mutants, AWSEM, molecular dynamics, Alzheimer's
Citation

Knapp, Kaitlin. "Exploring Amyloid-B Aggregation Pathways and Identifying Key Differences Between AB40, AB42, and Known Mutants." (2021) Diss., Rice University. https://hdl.handle.net/1911/111747.

Has part(s)
Forms part of
Published Version
Rights
Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.
Link to license
Citable link to this page