Theoretical and Experimental Approaches to Identification of a Fiber Surface Cell Binding Domain in Collagen and its Application in Tissue Engineering.

Extract

Type I collagen comprises between 75-95% of the stationary extracellular matrix of most tissues, forming a continuum in which most of the static cells are anchored. Collagen serves as the track for haptotactic cell migration. The junction between collagen, its receptor integrins, and the cells’ cytoskeleton plays a crucial role in cell differentiation and morphogenesis by serving as the agent for transducing mechanical forces into chemical and biochemical work. The physiological, functional organization of collagen is the solid state in the form of a network of fibers. The only molecules available for engaging the receptors are those located on the fiber surface. Cryogenic scanning force microscopy (SFM) of single molecules of collagen allowed us to correlate surface features with known sequence and stereochemical markers within collagen. Theoretical conformational studies to locate markers for intermolecular recognition and allosteric binding showed that collagen a 1(1) chain residues ⁷⁶⁶GTPGPQGIAGQRGVV⁷⁸⁰ generate a distinctive conformation, characterized by a relatively stable (3-bend at the core (Fig. 1) within the triple helical polyproline II conformation extant in the rest of the molecule (1).