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Updated: May 10, 2025
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In Situ Monitoring of Transiently Formed Molecular Chaperone Assemblies in Bacteria, Yeast, and Human Cells
Published on: September 2, 2019
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The evolution and diversification of the Hsp90 co-chaperone system
Sonja Engler1, Johannes Buchner1
1Center for Protein Assemblies (CPA), Department Bioscience, TUM School of Natural Sciences, Technical University of Munich, Ernst-Otto-Fischer-Strasse 8, D-85748 Garching, Germany.
Biological Chemistry
|April 22, 2025
Summary
The heat shock protein 90 (Hsp90) chaperone machinery utilizes numerous co-chaperones to regulate cellular proteostasis. The evolution and expansion of these Hsp90 co-chaperones have increased its functional importance in humans compared to yeast.
Area of Science:
- Molecular Biology
- Cell Biology
- Evolutionary Biology
Background:
- The molecular chaperone heat shock protein 90 (Hsp90) is crucial for proteostasis in eukaryotic cells.
- Hsp90 functions within a complex machinery involving numerous co-chaperones that modulate its activity.
- The number of known Hsp90 co-chaperones has significantly increased from yeast to humans.
Purpose of the Study:
- To provide an overview of Hsp90 co-chaperones.
- To focus on the roles of co-chaperones in regulating Hsp90 function.
- To examine the evolutionary trajectory of Hsp90 co-chaperones from yeast to humans.
Main Methods:
- Literature review of Hsp90 co-chaperone research.
- Comparative analysis of Hsp90 co-chaperone numbers and functions across species.
- Focus on evolutionary expansion and functional diversification.
Main Results:
- The Hsp90 chaperone machinery is characterized by a growing number of structurally and functionally diverse co-chaperones.
- Hsp90 co-chaperone numbers have expanded from 14 in yeast to over 40 in humans.
- While Hsp90 structure is conserved, its functional importance in humans is linked to co-chaperone evolution.
Conclusions:
- Hsp90 co-chaperones are key drivers of Hsp90's expanded roles in higher eukaryotes.
- The evolution of co-chaperone diversity underlies Hsp90's increased influence on the human proteome.
- Understanding Hsp90 co-chaperone dynamics is essential for comprehending cellular regulation and evolution.
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