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Biochemical Reconstitution of Steroid Receptor•Hsp90 Protein Complexes and Reactivation of Ligand Binding
Published on: September 21, 2011
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Brassinosteroid nuclear signaling recruits HSP90 activity
Despina Samakovli1, Theoni Margaritopoulou, Constantinos Prassinos
1Laboratory of Molecular Biology, Agricultural University of Athens, Iera Odos 75, 118 55, Athens, Greece.
The New Phytologist
|May 9, 2014
Summary
Heat shock protein 90 (HSP90) is crucial for brassinosteroid (BR) signaling in plants. Active HSP90 maintains BIN2 nuclear function, regulating plant development.
Area of Science:
- Plant molecular biology
- Cell signaling
- Protein-protein interactions
Background:
- Heat shock protein 90 (HSP90) plays a regulatory role in cellular signaling pathways.
- Brassinosteroids (BRs) are key plant hormones regulating diverse developmental processes.
Purpose of the Study:
- To investigate the role and mechanism of HSP90 in brassinosteroid (BR) signaling in Arabidopsis thaliana.
- To elucidate the interaction between HSP90, BIN2, and BRs in regulating gene expression and plant development.
Main Methods:
- Genetic, physiological, cytological, and gene expression analyses.
- Live cell imaging and pharmacological treatments with HSP90 inhibitor (GDA) and BR (BL).
- Analysis of protein localization and interaction dynamics.
Main Results:
- HSP90 is essential for maintaining the nuclear localization and function of BIN2, a BR signaling regulator.
- BR treatment (BL) induces translocation of HSP90-BIN2 complexes from the nucleus to the cytoplasm.
- HSP90 activity influences the expression of BR-responsive genes.
Conclusions:
- HSP90 acts as a central regulator in BR signaling by controlling BIN2 nuclear function.
- BR signaling involves HSP90-mediated trafficking of BIN2-HSP90 complexes, impacting downstream gene expression and plant development.
Keywords:
Arabidopsis thalianaBIN2brassinosteroid signalinggene expressionheat shock protein 90 (HSP90)More Related Videos
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