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ECM Protein Nanofibers and Nanostructures Engineered Using Surface-initiated Assembly
Published on: April 17, 2014
Fibrillin-1 microfibril deposition is dependent on fibronectin assembly
Rachel Kinsey1, Matthew R Williamson, Shazia Chaudhry
1Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Science, Michael Smith Building, Oxford Road, University of Manchester, Manchester M139PT, UK.
Journal of Cell Science
|July 26, 2008
Summary
Newly deposited microfibrils and fibronectin assemble together in fibroblasts. Fibronectin assembly, regulated by integrin receptors, is crucial for microfibril deposition, impacting cell structure.
Area of Science:
- Cell Biology
- Extracellular Matrix Research
- Biochemistry
Background:
- Microfibrils are essential extracellular matrix components.
- Fibronectin assembly is a critical process regulated by integrin receptors.
- The relationship between microfibril deposition and fibronectin assembly requires further elucidation.
Purpose of the Study:
- To investigate the role of fibronectin assembly in microfibril deposition.
- To determine if integrin receptors influence microfibril formation.
- To explore the regulatory mechanisms of pericellular microfibril assembly.
Main Methods:
- Utilizing primary fibroblasts and beta1-integrin-receptor-null fibroblasts.
- Employing fibronectin depletion and supplementation techniques.
- Disrupting Rho kinase and blocking cell surface integrin receptors.
- Analyzing fibronectin(RGE/RGE) mutant mouse fibroblast cultures.
Main Results:
- Newly deposited microfibrils strongly colocalize with fibronectin.
- Fibronectin depletion inhibits microfibril formation, while supplementation rescues it.
- Suppression of fibronectin and microfibril deposition observed in beta1-integrin-receptor-null fibroblasts, integrin blockage, and Rho kinase disruption.
- Antibody activation of beta1 integrins fails to rescue microfibril assembly in fibronectin-depleted cultures.
- Reduced extracellular assembly of fibronectin and microfibrils in alpha5beta1 integrin-deficient fibroblasts.
Conclusions:
- Pericellular microfibril assembly is regulated by fibronectin fibrillogenesis.
- Integrin receptors play a significant role in coordinating fibronectin and microfibril deposition.
- Fibronectin assembly is a prerequisite for effective microfibril formation in the extracellular matrix.
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