PTPL1/FAP-1 negatively regulates TRIP6 function in lysophosphatidic acid-induced cell migration

J Biol Chem. 2007 Aug 17;282(33):24381-7. doi: 10.1074/jbc.M701499200. Epub 2007 Jun 25.

Abstract

The LIM domain-containing TRIP6 (Thyroid Hormone Receptor-interacting Protein 6) is a focal adhesion molecule known to regulate lysophosphatidic acid (LPA)-induced cell migration through interaction with the LPA2 receptor. LPA stimulation targets TRIP6 to the focal adhesion complexes and promotes c-Src-dependent phosphorylation of TRIP6 at Tyr-55, which creates a docking site for the Crk Src homology 2 domain, thereby promoting LPA-induced morphological changes and cell migration. Here we further demonstrate that a switch from c-Src-mediated phosphorylation to PTPL1/Fas-associated phosphatase-1-dependent dephosphorylation serves as an inhibitory feedback control mechanism of TRIP6 function in LPA-induced cell migration. PTPL1 dephosphorylates phosphotyrosine 55 of TRIP6 in vitro and inhibits LPA-induced tyrosine phosphorylation of TRIP6 in cells. This negative regulation requires a direct protein-protein interaction between these two molecules and the phosphatase activity of PTPL1. In contrast to c-Src, PTPL1 prevents TRIP6 turnover at the sites of adhesions. As a result, LPA-induced association of TRIP6 with Crk and the function of TRIP6 to promote LPA-induced morphological changes and cell migration are inhibited by PTPL1. Together, these results reveal a novel mechanism by which PTPL1 phosphatase plays a counteracting role in regulating TRIP6 function in LPA-induced cell migration.

Publication types

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

MeSH terms

  • ATPases Associated with Diverse Cellular Activities
  • Adaptor Proteins, Signal Transducing / physiology*
  • Animals
  • Cell Line
  • Cell Movement*
  • Feedback, Physiological*
  • Humans
  • LIM Domain Proteins
  • Lysophospholipids / physiology*
  • Mice
  • Phosphorylation
  • Proteasome Endopeptidase Complex
  • Protein Binding
  • Protein Phosphatase 1
  • Protein Tyrosine Phosphatase, Non-Receptor Type 13
  • Protein Tyrosine Phosphatases / physiology*
  • Transcription Factors / physiology*
  • Transfection

Substances

  • Adaptor Proteins, Signal Transducing
  • LIM Domain Proteins
  • Lysophospholipids
  • PSMC5 protein, human
  • Transcription Factors
  • Protein Phosphatase 1
  • PTPN13 protein, human
  • Protein Tyrosine Phosphatase, Non-Receptor Type 13
  • Protein Tyrosine Phosphatases
  • Ptpn13 protein, mouse
  • Proteasome Endopeptidase Complex
  • ATPases Associated with Diverse Cellular Activities
  • lysophosphatidic acid