FAK induces expression of Prx1 to promote tenascin-C-dependent fibroblast migration

J Cell Biol. 2003 Apr 28;161(2):393-402. doi: 10.1083/jcb.jcb.200302126.

Abstract

Fibroblast migration depends, in part, on activation of FAK and cellular interactions with tenascin-C (TN-C). Consistent with the idea that FAK regulates TN-C, migration-defective FAK-null cells expressed reduced levels of TN-C. Furthermore, expression of FAK in FAK-null fibroblasts induced TN-C, whereas inhibition of FAK activity in FAK-wild-type cells had the opposite effect. Paired-related homeobox 1 (Prx1) encodes a homeobox transcription factor that induces TN-C by interacting with a binding site within the TN-C promoter, and it also promotes fibroblast migration. Therefore, we hypothesized that FAK regulates TN-C by controlling the DNA-binding activity of Prx1 and/or by inducing Prx1 expression. Prx1-homeodomain binding site complex formation observed with FAK-wild-type fibroblasts failed to occur in FAK-null fibroblasts, yet expression of Prx1 in these cells induced TN-C promoter activity. Thus, FAK is not essential for Prx1 DNA-binding activity. However, activated FAK was essential for Prx1 expression. Functionally, Prx1 expression in FAK-null fibroblasts restored their ability to migrate toward fibronectin, in a manner that depends on TN-C. These results appear to be relevant in vivo because Prx1 and TN-C expression levels were reduced in FAK-null embryos. This paper suggests a model whereby FAK induces Prx1, and subsequently the formation of a TN-C-enriched ECM that contributes to fibroblast migration.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Binding Sites / genetics
  • Cell Movement / drug effects
  • Cell Movement / genetics*
  • Cells, Cultured
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Embryo, Mammalian
  • Fibroblasts / cytology
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism*
  • Focal Adhesion Kinase 1
  • Focal Adhesion Protein-Tyrosine Kinases
  • Gene Expression Regulation, Developmental / genetics*
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism
  • Mice
  • Mice, Knockout
  • Models, Biological
  • Peroxidases / genetics
  • Peroxidases / metabolism*
  • Promoter Regions, Genetic / genetics
  • Protein Structure, Tertiary / genetics
  • Protein-Tyrosine Kinases / antagonists & inhibitors
  • Protein-Tyrosine Kinases / deficiency*
  • Protein-Tyrosine Kinases / genetics
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Tenascin / genetics
  • Tenascin / metabolism*

Substances

  • DNA-Binding Proteins
  • Homeodomain Proteins
  • Saccharomyces cerevisiae Proteins
  • Tenascin
  • PRX1 protein, S cerevisiae
  • Peroxidases
  • Protein-Tyrosine Kinases
  • Focal Adhesion Kinase 1
  • Focal Adhesion Protein-Tyrosine Kinases
  • Ptk2 protein, mouse