Secreted versus membrane-anchored collagenases: relative roles in fibroblast-dependent collagenolysis and invasion

J Biol Chem. 2009 Aug 21;284(34):23001-11. doi: 10.1074/jbc.M109.002808. Epub 2009 Jun 19.

Abstract

Fibroblasts degrade type I collagen, the major extracellular protein found in mammals, during events ranging from bulk tissue resorption to invasion through the three-dimensional extracellular matrix. Current evidence suggests that type I collagenolysis is mediated by secreted as well as membrane-anchored members of the matrix metalloproteinase (MMP) gene family. However, the roles played by these multiple and possibly redundant, degradative systems during fibroblast-mediated matrix remodeling is undefined. Herein, we use fibroblasts isolated from Mmp13(-/-), Mmp8(-/-), Mmp2(-/-), Mmp9(-/-), Mmp14(-/-) and Mmp16(-/-) mice to define the functional roles for secreted and membrane-anchored collagenases during collagen-resorptive versus collagen-invasive events. In the presence of a functional plasminogen activator-plasminogen axis, secreted collagenases arm cells with a redundant collagenolytic potential that allows fibroblasts harboring single deficiencies for either MMP-13, MMP-8, MMP-2, or MMP-9 to continue to degrade collagen comparably to wild-type fibroblasts. Likewise, Mmp14(-/-) or Mmp16(-/-) fibroblasts retain near-normal collagenolytic activity in the presence of plasminogen via the mobilization of secreted collagenases, but only Mmp14 (MT1-MMP) plays a required role in the collagenolytic processes that support fibroblast invasive activity. Furthermore, by artificially tethering a secreted collagenase to the surface of Mmp14(-/-) fibroblasts, we demonstrate that localized pericellular collagenolytic activity differentiates the collagen-invasive phenotype from bulk collagen degradation. Hence, whereas secreted collagenases arm fibroblasts with potent matrix-resorptive activity, only MT1-MMP confers the focal collagenolytic activity necessary for supporting the tissue-invasive phenotype.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Becaplermin
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Collagen Type I / metabolism*
  • Collagenases / metabolism*
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism*
  • Fluorescent Antibody Technique
  • Matrix Metalloproteinase 13 / genetics
  • Matrix Metalloproteinase 13 / physiology
  • Matrix Metalloproteinase 14 / genetics
  • Matrix Metalloproteinase 14 / physiology
  • Matrix Metalloproteinase 16 / genetics
  • Matrix Metalloproteinase 16 / physiology
  • Matrix Metalloproteinase 2 / genetics
  • Matrix Metalloproteinase 2 / physiology
  • Matrix Metalloproteinase 8 / genetics
  • Matrix Metalloproteinase 8 / physiology
  • Matrix Metalloproteinase 9 / genetics
  • Matrix Metalloproteinase 9 / physiology
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Microscopy, Electron
  • Plasminogen / pharmacology
  • Platelet-Derived Growth Factor / pharmacology
  • Protease Inhibitors / pharmacology
  • Proto-Oncogene Proteins c-sis
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tissue Inhibitor of Metalloproteinase-2 / genetics
  • Tissue Inhibitor of Metalloproteinase-2 / physiology

Substances

  • Collagen Type I
  • Membrane Proteins
  • Platelet-Derived Growth Factor
  • Protease Inhibitors
  • Proto-Oncogene Proteins c-sis
  • Tissue Inhibitor of Metalloproteinase-2
  • Becaplermin
  • Plasminogen
  • Collagenases
  • Matrix Metalloproteinase 13
  • Matrix Metalloproteinase 16
  • Matrix Metalloproteinase 2
  • Matrix Metalloproteinase 8
  • Matrix Metalloproteinase 9
  • Matrix Metalloproteinase 14