Crystal structure of an Hsp90-nucleotide-p23/Sba1 closed chaperone complex
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Summary
This summary is machine-generated.Heat shock protein 90 (Hsp90) is crucial for cellular processes and cancer. This study reveals the Hsp90 chaperone
Area Of Science
- Biochemistry
- Molecular Biology
- Structural Biology
Background
- Heat shock protein 90 (Hsp90) is a vital molecular chaperone regulating eukaryotic signaling pathways.
- Hsp90 is a promising target for cancer chemotherapy.
- Previous structural studies focused on isolated Hsp90 domains, leaving the full dimer's dynamics unclear.
Purpose Of The Study
- To elucidate the structural arrangement and ATP-dependent dynamics of the full-length Hsp90 dimer.
- To understand the Hsp90 chaperone's 'closed' state architecture.
- To investigate the role of co-chaperone p23/Sba1 in stabilizing Hsp90.
Main Methods
- X-ray crystallography of full-length yeast Hsp90.
- Complex formation with an ATP analogue and co-chaperone p23/Sba1.
Main Results
- The crystal structure of the closed state of the Hsp90 dimer was determined.
- Extensive inter-domain and inter-chain interactions within the Hsp90 complex were revealed.
- ATP binding induces conformational changes in the amino-terminal domain.
- The co-chaperone p23/Sba1 stabilizes the closed Hsp90 conformation.
- The closed Hsp90 structure presents a bipartite binding surface, not enclosing client proteins.
Conclusions
- The study provides a detailed structural model of the Hsp90 chaperone in its closed state.
- Hsp90's client binding mechanism involves a dynamic bipartite surface coupled to its ATPase cycle.
- Understanding Hsp90 structure-function is critical for developing targeted cancer therapies.