Metalloproteinases (MMPs)

MMPs are a family of 20+ members of secreted or membrane-bound endopeptidases that require zinc for their activity. (Dzwonek, FEBS Letters 2004; 567:129–135). MMPs can process and degrade extracellular matrix proteins to regulate tissue remodeling, wound healing, angiogenesis, and other processes. MMPs are associated with cell migration and invasion in pathologies such as arthritis and cancer tumor progression. Most MMPs are secreted in their inactive, or proforms, and thus activation is key to regulating their degradative activity.

For most MMPs, including MMP-1, -3, -7, and -9, serine proteases such as plasmin, urokinase-type plasminogen activators, and furin are known to initiate activation. In addition, some MMPs also activate other MMPs; for example, MT1-MMP activates MMP-2 or MMP-13 and MMP-3 activates MMP-9. Once activated, MMPs can be inhibited by the noncovalently bound tissue inhibitors of metalloproteinases (TIMPs). Four TIMPs have been identified: TIMP-1, -2, -3, and -4. Merck offers a full range of MMP antibodies, proteins, and activity assays for research into the function and regulation of metalloproteinases.

Eight domain motifs for the matrix metallopreteinases, or matrixins, are identified to date.

Nagase, H. & Woessner, J.F. J Biol Chem 1999; 274:21491-21494.