Functional properties of collagen and elastin

Abstract

As the major structural component of the body, collagen constitutes almost one-third of the total protein. Its structural role can be readily appreciated by its abundance in skin, tendon, bone and cartilage but the protein is also present in a number of specialized structures, such as cornea and basement membranes. Consistent with this diversity of function there are now known to be several genetically distinct forms of collagen which can be broadly classified into two groups: the interstitial collagens (types I, II and III) that act as load-bearing fibres and the non-fibrous types that are often located pericellularly but have wider functions in mediating interactions between matrix constituents and the cell membrane. The function of elastin is less complex and this component provides the elastic recoil necessary in tissues such as skin, certain ligaments and, to an even greater extent, in the lung and cardiovascular system. This chapter reviews current knowledge of the structure, biosynthesis and degradation of collagen and elastin in relation to their functions. In addition, the extent to which this basic knowledge can now be applied to further an understanding of particular disease states involving connective tissues is reviewed.