Abstract
Extracellular matrices (ECMs) contain a mixture of fibrillar and nonfibrillar macromolecular components, which interact through a range of covalent and noncovalent associations to form a composite structure (1–3). It is the ECM that defines the architecture, the form, and the biomechanical properties of many tissues. In order to perform their functional roles, many of the important noncollagenous components of extracellular matrices are required to be immobilized or focally located within tissues (4,5). Positioning of macromolecules within tissues occurs as a consequence of specific protein-protein and protein-carbohydrate interactions. Aggrecan, the large aggregating proteoglycan, is noncovalently associated with hyaluronan via its N-terminal domain and this association is further stabilised by link protein (6). A large immobilized hydrated aggregate structure is formed, with up to 50 aggrecan molecules per hyaluronan chain, which gives articular cartilage the ability to resist the high compressive loads generated during joint articulation. Other examples of specific intermolecular associations include the binding of cell surface integrins to fibronectins and collagenous proteins (7) and growth factors to heparan sulphate (8). A variety of methods have been developed to investigate the affinity and specificity of these associations and their sensitivity to environmental factors such as pH and metal ion concentration. Many techniques for analyzing binding equilibria or kinetics require either the ligand or substrate to be linked to a solid support. As a consequence of derivitization and high local concentrations, binding equilibria can be significantly perturbed.
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© 2001 Humana Press Inc., Totowa, NJ
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Gribbon, P., Heng, B.C., Hardingham, T.E. (2001). Novel Confocal-FRAP Analysis of Carbohydrate-Protein Interactions Within the Extracellular Matrix. In: Iozzo, R.V. (eds) Proteoglycan Protocols. Methods in Molecular Biology™, vol 171. Humana Press. https://doi.org/10.1385/1-59259-209-0:487
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DOI: https://doi.org/10.1385/1-59259-209-0:487
Publisher Name: Humana Press
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Online ISBN: 978-1-59259-209-8
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