New insights into the mutable collagenous tissue of Paracentrotus lividus: preliminary results*

The mechanically adaptable connective tissue of echinoderms (Mutable Collagenous Tissue—MCT), which can undergo drastic nervously-mediated changes in mechanical properties, represents a promising model for biomaterial design and biomedical applications. MCT could be a source of, or an inspiration for, new composite materials whose molecular inter­actions and structural conformation can be changed in response to external stimuli. MCT is composed mostly of collagen fibrils, comparable to those of mammals, plus a variety of other components, including other fibrillar structures, proteo­glycans and glycoproteins. This contribution presents the preliminary results of a detailed analysis of MCT components in the sea-urchin Paracentrotus lividus, focusing on biochemical characterization of the fibrils and biomolecular analysis of the presumptive glycoproteins involved. The final aims will be to confirm the presence and the role of these glycoproteins in echinoids and to manipulate simpler components in order to produce a composite with mutable mechanical properties.