Type III and V collagens modulate the expression and assembly of EDA(+) fibronectin in the extracellular matrix of defective Ehlers-Danlos syndrome fibroblasts.

Abstract

BACKGROUND:

Alternative splicing of EDA fibronectin (FN) region is a cell type- and development-regulated mechanism controlled by pathological processes, growth factors and extracellular matrix (ECM). Classic and vascular Ehlers-Danlos syndrome (cEDS and vEDS) are connective tissue disorders caused by COL5A1/COL5A2 and COL3A1 gene mutations, leading to an in vivo abnormal collagen fibrillogenesis and to an in vitro defective organisation in the ECM of type V (COLLV) and type III collagen (COLLIII). These defects induce the FN-ECM disarray and the decrease of COLLs and FN receptors, the α2β1 and α5β1 integrins. Purified COLLV and COLLIII restore the COLL-FN-ECMs in both EDS cell strains.

METHODS:

Real-time PCR, immunofluorescence microscopy, and Western blotting were used to investigate the effects of COLLs on FN1 gene expression, EDA region alternative splicing, EDA(+)-FN-ECM assembly, α5β1 integrin and EDA(+)-FN-specific α9 integrin subunit organisation, α5β1 integrin and FAK co-regulation in EDS fibroblasts.

RESULTS:

COLLV-treated cEDS and COLLIII-treated vEDS fibroblasts up-regulate the FN1 gene expression, modulate the EDA(+) mRNA maturation and increase the EDA(+)-FN levels, thus restoring a control-like FN-ECM, which elicits the EDA(+)-FN-specific α9β1 integrin organisation, recruits the α5β1 integrin and switches on the FAK binding and phosphorylation.

CONCLUSION:

COLLs regulate the EDA(+)-FN-ECM organisation at transcriptional and post-transcriptional level and activate the α5β1-FAK complexes. COLLs also recruit the α9β1 integrin involved in the assembly of the EDA(+)-FN-ECM in EDS cells.

GENERAL SIGNIFICANCE:

The knowledge of the COLLs-ECM role in FN isotype expression and in EDA(+)-FN-ECM-mediated signal transduction adds insights in the ECM remodelling mechanisms in EDS cells.

• Authors: Nicoletta Zoppi, Marco Ritelli, Marina Colombi
• Journal: Biochimica et biophysica acta (Biochim Biophys Acta) Vol. 1820 Issue 10 Pg. 1576-87 (Oct 2012) ISSN: 0006-3002 [Print] Netherlands
• PMID: 22705941 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2012 Elsevier B.V. All rights reserved.

Chemical References

• Collagen Type III
• Collagen Type V
• Fibronectins
• Integrin alpha5beta1
• Integrins
• Protein Isoforms
• extra domain A fibronectin, human
• integrin alpha 9 beta 1
• Focal Adhesion Kinase 1
• PTK2 protein, human

Topics

• Case-Control Studies
• Cells, Cultured
• Collagen Type III (pharmacology)
• Collagen Type V (pharmacology)
• Ehlers-Danlos Syndrome (metabolism, pathology)
• Extracellular Matrix (drug effects, metabolism)
• Female
• Fibroblasts (drug effects, metabolism, pathology)
• Fibronectins (genetics, metabolism)
• Focal Adhesion Kinase 1 (metabolism, physiology)
• Gene Expression Regulation (drug effects)
• Humans
• Integrin alpha5beta1 (metabolism)
• Integrins (metabolism)
• Male
• Protein Isoforms (genetics, metabolism)
• Protein Multimerization (drug effects)