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10:32
Fabrication Process of Silicone-based Dielectric Elastomer Actuators
Published on: February 1, 2016
Designed helical peptides inhibit an intramembrane protease.
Chittaranjan Das1, Oksana Berezovska, Thekla S Diehl
1Center for Neurologic Diseases, Harvard Medical School, Boston, Massachusetts 02115, USA.
Journal of the American Chemical Society
|September 25, 2003
Summary
Short helical peptides inhibit gamma-secretase by disrupting substrate binding, offering a new therapeutic strategy for Alzheimer's disease. D-amino acid peptides show the most promise.
Area of Science:
- Biochemistry
- Molecular Biology
- Neuroscience
Background:
- Gamma-secretase is crucial for cleaving amyloid precursor protein, a process linked to Alzheimer's disease pathogenesis.
- This enzyme belongs to a novel class of intramembrane proteases.
- Substrate transmembrane domains may adopt a helical conformation upon protease interaction.
Purpose of the Study:
- To investigate the potential of helical peptides as inhibitors of gamma-secretase.
- To explore the mechanism of gamma-secretase inhibition by helical peptides.
- To assess the therapeutic potential of helical peptides for Alzheimer's disease.
Main Methods:
- Design and synthesis of helical peptides, including d-amino acid variants.
- Inhibition assays in cell-based systems and purified enzyme preparations.
- Fluorescence lifetime imaging microscopy in intact cells.
Main Results:
- Helical peptides effectively inhibit gamma-secretase activity.
- Peptides composed entirely of d-amino acids exhibit the highest potency.
- Disruption of helicity significantly reduces inhibitory activity.
- Helical peptides interfere with substrate-protease binding at a site distinct from the active site.
Conclusions:
- Helical conformation is critical for potent gamma-secretase inhibition.
- Helical peptides act by interacting with an initial substrate docking site.
- This strategy offers a promising approach for developing specific inhibitors of intramembrane proteases.
- D-amino acid helical peptides represent potential therapeutic leads for Alzheimer's disease.
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