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Published on: September 28, 2020
Coiled-Coil Domain Kinking Controls Laminin-332 Cleavage by Elastase
Lucky Akter1, Romain Amyot2, Robert Großmann3
1WPI Nano Life Science Institute, Kanazawa University, Kanazawa, Ishikawa 920-1167, Japan; Graduate School of Advanced Science and Technology, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan.
Journal of Molecular Biology
|August 14, 2026
Summary
Coiled-coil kinking in laminin-332 directs pancreatic elastase cleavage to specific sites, generating functional fragments. This conformational control mechanism is crucial for basement membrane processing and cell adhesion.
Area of Science:
- Biochemistry
- Cell Biology
- Structural Biology
Background:
- Laminins are key basement membrane proteins involved in cell adhesion.
- The flexible coiled-coil domain of laminins is essential for structural integrity, but its flexibility and function are poorly understood.
Purpose of the Study:
- To investigate the role of coiled-coil flexibility in laminin-332 processing by pancreatic elastase.
- To elucidate the mechanism by which coiled-coil kinking directs enzymatic cleavage.
Main Methods:
- High-speed atomic force microscopy (HS-AFM) for real-time visualization of laminin-332 digestion.
- Integration of HS-AFM with AlphaFold structure prediction and normal-mode flexible fitting (NMFF).
Main Results:
- Coiled-coil kinking was observed to direct elastase cleavage specifically to the hinge site of laminin-332.
- This directed cleavage generates the functional elastase 8 (E8) fragment containing the integrin-binding site.
- Extended coiled-coil conformations were cleaved randomly, leading to complete degradation.
Conclusions:
- A novel mechanism of conformational control in proteolytic processing of laminin-332 has been identified.
- Defined coiled-coil kinking is essential for generating specific functional fragments of laminin-332.
- Dynamic models provide atomic-scale insight into the hinge-flexing mechanism of the laminin coiled-coil.
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