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Rapid Generation of Amyloid from Native Proteins In vitro
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Nucleolar Sequestration: Remodeling Nucleoli Into Amyloid Bodies
Miling Wang1,2, Michael Bokros1,2, Phaedra Rebecca Theodoridis1,2
1Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, United States.
Frontiers in Genetics
|December 12, 2019
Summary
The nucleolus can sequester proteins, forming amyloid bodies (A-bodies) through an amyloidogenic program. This process, involving rIGSRNA and ACM motifs, offers insights into membraneless compartments and neurological disorders.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The nucleolus, a key nuclear domain, was discovered to immobilize proteins 20 years ago.
- This process, termed nucleolar sequestration, involves proteins being temporarily sequestered within the nucleolus.
Purpose of the Study:
- To review progress in understanding the physiological roles of nucleolar sequestration.
- To elucidate the mechanisms underlying protein immobilization within the nucleolus.
Main Methods:
- Review of existing literature on nucleolar sequestration and protein immobilization.
- Analysis of the proposed biogenesis of amyloid bodies (A-bodies).
Main Results:
- Protein immobilization can occur via a programmed amyloidogenic process, forming amyloid bodies (A-bodies).
- A-bodies are large, fibrous, membraneless organelles with amyloid-like characteristics.
- A working model for A-body biogenesis is proposed, involving rIGSRNA and amyloid-converting motifs (ACM).
Conclusions:
- Amyloid bodies serve as a model for studying the assembly of membraneless compartments.
- The study of A-bodies may offer insights into pathological amyloidogenesis in neurological disorders.
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