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Updated: Jun 24, 2025
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Generating a Fractal Microstructure of Laminin-111 to Signal to Cells
Published on: September 28, 2020
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Polymerizing laminins in development, health, and disease
Peter D Yurchenco1, Arkadiusz W Kulczyk2
1Department of Pathology & Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA.
The Journal of Biological Chemistry
|June 2, 2024
Summary
Polymerizing laminins form the initial basement membrane scaffold by self-assembling into a polymer node. Mutations in this process cause LN-lamininopathies, a group of genetic diseases.
Area of Science:
- Biochemistry
- Cell Biology
- Structural Biology
Background:
- Basement membranes (BMs) are crucial extracellular matrices essential for tissue structure and function.
- Laminins are key glycoproteins that self-assemble to form the initial BM scaffold.
- Subsequent assembly involves nidogens, collagen IV, and proteoglycans.
Purpose of the Study:
- To elucidate the self-assembly mechanism of polymerizing laminins.
- To determine the structural basis of the laminin polymer node.
- To understand how mutations lead to LN-lamininopathies.
Main Methods:
- Cryo-electron microscopy
- AlphaFold2 modeling
- Biochemical studies
Main Results:
- The laminin polymer node, the repeating unit of the BM scaffold, forms a near-symmetrical triskelion structure.
- Interactions between LN domain surface residues drive self-assembly.
- Mutations affecting these interactions result in self-assembly failures.
Conclusions:
- The study reveals the precise structural organization of the laminin polymer node.
- Understanding these interactions is critical for comprehending LN-lamininopathies.
- This work provides insights into the pathogenesis of genetic disorders affecting basement membrane formation.
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