Extracellular matrix remodelling: the role of matrix metalloproteinases

Matrix metalloproteinases (MMPs) are a growing family of metalloendopeptidases that cleave the protein components of the extracellular matrix and thereby play a central role in tissue remodelling. For many years following their discovery, MMPs were believed to function primarily as regulators of ECM composition and to facilitate cell migration simply by removing barriers such as collagen. It is becoming increasingly clear, however, that MMPs are implicated in the functional regulation of a host of non-ECM molecules that include growth factors and their receptors, cytokines and chemokines, adhesion receptors and cell surface proteoglycans, and a variety of enzymes. MMPs therefore play an important role in the…