Phosphorylation of membrane type 1-matrix metalloproteinase (MT1-MMP) and its vesicle-associated membrane protein 7 (VAMP7)-dependent trafficking facilitate cell invasion and migration

J Biol Chem. 2011 Dec 16;286(50):43405-16. doi: 10.1074/jbc.M111.297069. Epub 2011 Oct 14.

Abstract

In multicellular organisms, uncontrolled movement of cells can contribute to pathological conditions, such as multiple sclerosis and cancer. In highly aggressive tumors, the expression of matrix metalloproteinases (MMPs) is linked to the capacity of tumor cells to invade surrounding tissue and current research indicates that the membrane-anchored membrane type 1-matrix metalloproteinase (MT1-MMP) has a central role in this process. Endocytosis and trafficking of MT1-MMP are essential for its proper function, and here we examine the phosphorylation, internalization, and recycling of this enzyme, and the associated biochemical signaling in HeLa and HT-1080 fibrosarcoma cells. Activation of protein kinase C with phorbol 12-myristate 13-acetate resulted in phosphorylation of endogenous MT1-MMP at Thr(567) in vivo. Mutation of Thr(567) to alanine (to mimic non-phosphorylated MT1-MMP) reduced internalization of MT1-MMP, whereas mutation of Thr(567) to glutamic acid (to mimic phosphorylation) resulted in decreased levels of MT1-MMP on the cell surface. The endosomal trafficking and recycling of MT1-MMP was found to be dependent upon Rab7 and VAMP7, and blocking the function of these proteins reduced cell migration and invasion. Intracellular trafficking of MT1-MMP was observed to be coupled to the trafficking of integrin α5 and phosphorylation of ERK that coincided with this was dependent on phosphorylation of MT1-MMP. Together, these results reveal important roles for MT1-MMP phosphorylation and trafficking in both cell signaling and cell invasion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Cell Line
  • Cell Movement / genetics
  • Cell Movement / physiology
  • Electrophoresis, Polyacrylamide Gel
  • Endosomes / genetics
  • Endosomes / metabolism
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism
  • HeLa Cells
  • Humans
  • Immunoprecipitation
  • Matrix Metalloproteinase 14 / genetics
  • Matrix Metalloproteinase 14 / metabolism*
  • Microscopy, Fluorescence
  • Mutation
  • Phosphorylation / genetics
  • Phosphorylation / physiology
  • R-SNARE Proteins / genetics
  • R-SNARE Proteins / metabolism*
  • rab GTP-Binding Proteins / genetics
  • rab GTP-Binding Proteins / metabolism
  • rab7 GTP-Binding Proteins

Substances

  • R-SNARE Proteins
  • VAMP7 protein, human
  • rab7 GTP-Binding Proteins
  • rab7 GTP-binding proteins, human
  • Matrix Metalloproteinase 14
  • GTP-Binding Proteins
  • RAB8A protein, human
  • rab GTP-Binding Proteins