Date of Award
1-1-2024
Language
English
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
College/School/Department
Department of Chemistry
Dissertation/Thesis Chair
Jia Sheng
Committee Members
Ken Halvorsen, Alex Shekhtman, Qiang Zhang
Keywords
Aminoglycosides, CUG repeat, Fluorescence spectroscopy, Microsatellite RNA expansions, RNA-ligand binding, Small molecule ligands
Subject Categories
Chemistry
Abstract
Pathogenic microsatellite RNA expansions are toxic and can cause neuronal degeneration and dysfunction. Therapeutics that eliminate or neutralize these RNA repeats hold great promise for the treatment of many neurodegenerative diseases because they are uniformly fatal but there is no effective treatment available today. New compounds targeting these pathogenic RNA repeat sequences represent new hope to treat these diseases. The overall goal of my dissertation is to develop a high-throughput screening assay to identify small ligands as potential drug candidates against disease-associated RNA repeats and probe binding mechanisms to guide the design of optimized drug candidates, and eventually validate therapeutic functions of these lead compounds by biological studies. We used oligonucleotides to mimic cellular RNA repeats and developed an efficient fluorescence-based assay, in which the fluorescence is minimized by covalently incorporating a fluorescein into the RNA repeat sequences to improve the sensitivity and reduce false positive readings. Our studies using a previously identified CUG repeat-targeting ligand as the positive control showed that this assay was consistent with other classic binding characterization techniques such as ITC, indicating its feasibility for wide applications to measure the binding constants and kinetics in a simple and high-throughput fashion. We further expanded this assay into a hit-to-lead platform by adding a novel fluorescence thermal melting assay with traditional UV Tm and complementary CD melting assays. We have optimized our HTS fluorescent assay and expanded the library of cyclic peptidomimetics with various chemical functionalities based on a leading hit. These novel cyclic peptide compounds and other identified ligands may hold great promise as therapeutic agents for the treatment of myotonic dystrophy and other RNA repeat-related diseases.
Recommended Citation
Chang, Zhihua, "Development Of Small Ligands Targeting Pathogenic Rna Repeats In Neurodegenerative Diseases" (2024). Legacy Theses & Dissertations (2009 - 2024). 3298.
https://scholarsarchive.library.albany.edu/legacy-etd/3298
