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Does the urokinase receptor exist in a latent form?
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yang Qiao Xi Lu, Fuzhou, Fujian 350002, China.
Cellular and Molecular Life Sciences : CMLS
|March 21, 2007
Summary
The urokinase receptor (uPAR) binds ligands for cellular functions, typically requiring urokinase. Structural studies reveal uPAR flexibility, suggesting a distinct latent form when unliganded.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- The urokinase receptor (uPAR) mediates diverse cellular functions through molecular interactions with various ligands.
- Urokinase is generally essential for uPAR to gain its ligand-binding capability.
Purpose of the Study:
- To investigate the structural basis of urokinase receptor (uPAR) ligand interactions.
- To explore the conformational flexibility of uPAR and its implications for receptor function.
Main Methods:
- X-ray crystallography was employed to determine the structure of uPAR.
- Structures were analyzed in complex with ligands and peptide inhibitors.
Main Results:
- X-ray studies revealed the domain organization flexibility of the urokinase receptor.
- Observed structural flexibility suggests that unliganded uPAR adopts a different conformation compared to its ligand-bound state.
Conclusions:
- The urokinase receptor exhibits significant conformational flexibility.
- Unliganded uPAR may exist in a latent conformation distinct from its active, ligand-binding form, impacting its cellular functions.
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