Article

Tropoelastin interacts with cell-surface glycosaminoglycans via its COOH-terminal domain

Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Journal of Biological Chemistry (Impact Factor: 4.6). 01/2006; 280(49):40939-47. DOI: 10.1074/jbc.M507309200
Source: PubMed

ABSTRACT Using a biochemical and cell biological approach, we have identified a cell interaction site at the carboxyl terminus of tropoelastin. Cell interactions with the COOH-terminal sequence are not through the elastin-binding protein (EBP67) because neither VGVAPG-like peptides nor galactoside sugars altered adhesion. Our results also show that cell adhesion to tropoelastin is not promoted by integrins. Through the use of mutant Chinese hamster ovary cell lines defective in glycosaminoglycan biosynthesis, as well as competition studies and enzymatic removal of specific cell-surface glycosaminoglycans, the tropoelastin-binding moieties on the cell surface were identified as heparan and chondroitin sulfate-containing glycosaminoglycans, with heparan sulfate being greatly preferred. Heparin affinity chromatography combined with cell adhesion assays identified the last 17 amino acids as the sequence element at the carboxyl terminus of tropoelastin responsible for the adhesive activity.

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    • "alternating hydrophobic and cross-linking domains to probe their contribution to the maturation of the coacervate. Conserved sequences investigated include a region rich in KP-type cross-linking domains corresponding to domains 8 to 14 in humans (Keeley, 2013), and a unique C-terminal sequence (domain 36 in human tropoelastin) that contains a tetra-basic motif important for cell and matrix interactions (Brown-Augsburger et al., 1996; Broekelmann et al., 2005). Polypeptides were typically constructed in the form of hydrophobic domains, represented by domains 20 and 24, alternating with cross-linking domains of KA-or KP-type. "
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    • "(2014), http://dx.doi.org/10.1016/j.matbio.2014.03.008 alternating hydrophobic and cross-linking domains to probe their contribution to the maturation of the coacervate. Conserved sequences investigated include a region rich in KP-type cross-linking domains corresponding to domains 8 to 14 in humans (Keeley, 2013), and a unique C-terminal sequence (domain 36 in human tropoelastin) that contains a tetra-basic motif important for cell and matrix interactions (Brown-Augsburger et al., 1996; Broekelmann et al., 2005). Polypeptides were typically constructed in the form of hydrophobic domains, represented by domains 20 and 24, alternating with cross-linking domains of KA-or KP-type. "
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