The gamma-secretase complex: machinery for intramembrane proteolysis
1Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo Bunkyoku, Tokyo 113-0033, Japan. iwatsubo@mol.f.u-tokyo.ac.jp
Current Opinion in Neurobiology
|June 15, 2004
Summary
Gamma-secretase, crucial for Alzheimer's disease pathology and tissue development, involves presenilin assembly with Aph-1, nicastrin, and Pen-2. This complex
Area of Science:
- Biochemistry
- Molecular Biology
- Neuroscience
Background:
- Gamma-secretase is a membrane protease complex with presenilin as its catalytic subunit.
- Presenilin is implicated in generating amyloid beta peptides in Alzheimer's disease and is essential for Notch signaling.
- Understanding gamma-secretase assembly and function is key to addressing neurodegenerative diseases and developmental processes.
Purpose of the Study:
- To elucidate the mechanism of gamma-secretase complex assembly.
- To understand how cofactor proteins contribute to gamma-secretase activity.
- To clarify the role of intramembrane proteolysis in cell signaling and disease.
Main Methods:
- The study integrates recent findings on protein interactions within the gamma-secretase complex.
- Focuses on the sequential assembly of presenilin with Aph-1, nicastrin, and Pen-2.
- Examines the acquisition of enzymatic activity and endoproteolysis.
Main Results:
- Aph-1 and nicastrin form a subcomplex that binds and stabilizes presenilin.
- Pen-2 is critical for conferring gamma-secretase activity and facilitating presenilin endoproteolysis.
- The assembly process is essential for the complex's proteolytic function.
Conclusions:
- The sequential assembly of gamma-secretase cofactors with presenilin is crucial for its enzymatic activity.
- Understanding this mechanism provides insights into intramembrane proteolysis regulation.
- This knowledge may contribute to developing therapeutic strategies for Alzheimer's disease.
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