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Ligand Nano-cluster Arrays in a Supported Lipid Bilayer
Published on: April 23, 2017
Laminin polymerization induces a receptor-cytoskeleton network
H Colognato1, D A Winkelmann, P D Yurchenco
1Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
The Journal of Cell Biology
|May 4, 1999
Summary
Laminin polymerization on muscle cells requires specific receptor interactions, driving cytoskeletal changes essential for basement membrane development and preventing muscular dystrophies.
Area of Science:
- Cell Biology
- Biochemistry
- Muscle Physiology
Background:
- Basement membrane formation relies on laminin polymerization.
- Laminin mutations cause muscular dystrophies due to basement membrane defects.
Purpose of the Study:
- Investigate laminin polymerization and receptor interactions on cell surfaces.
- Determine cellular responses mediated by laminin assembly.
Main Methods:
- Evaluated laminin polymer and receptor interactions on muscle cell surfaces.
- Assessed cellular responses including actin reorganization and tyrosine phosphorylation.
Main Results:
- Laminin preferentially polymerizes on muscle cells when bound to dystroglycan and alpha7beta1 integrin.
- Receptor binding facilitates laminin self-assembly into a polygonal network, requiring actin and tyrosine phosphorylation.
- This process induces reciprocal redistribution of receptors and cytoskeletal proteins like vinculin and dystrophin.
Conclusions:
- Laminin polymerization on cell surfaces is a cooperative process essential for cortical architecture.
- Requires laminin-receptor ligation, self-assembly, actin reorganization, and signaling.
- This mechanism is crucial for preventing basement membrane defects and associated muscular dystrophies.
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