The tyrosine phosphatase SHP2 regulates recovery of endothelial adherens junctions through control of β-catenin phosphorylation

Mol Biol Cell. 2012 Nov;23(21):4212-25. doi: 10.1091/mbc.E12-01-0038. Epub 2012 Sep 5.

Abstract

Impaired endothelial barrier function results in a persistent increase in endothelial permeability and vascular leakage. Repair of a dysfunctional endothelial barrier requires controlled restoration of adherens junctions, comprising vascular endothelial (VE)-cadherin and associated β-, γ-, α-, and p120-catenins. Little is known about the mechanisms by which recovery of VE-cadherin-mediated cell-cell junctions is regulated. Using the inflammatory mediator thrombin, we demonstrate an important role for the Src homology 2-domain containing tyrosine phosphatase (SHP2) in mediating recovery of the VE-cadherin-controlled endothelial barrier. Using SHP2 substrate-trapping mutants and an in vitro phosphatase activity assay, we validate β-catenin as a bona fide SHP2 substrate. SHP2 silencing and SHP2 inhibition both result in delayed recovery of endothelial barrier function after thrombin stimulation. Moreover, on thrombin challenge, we find prolonged elevation in tyrosine phosphorylation levels of VE-cadherin-associated β-catenin in SHP2-depleted cells. No disassembly of the VE-cadherin complex is observed throughout the thrombin response. Using fluorescence recovery after photobleaching, we show that loss of SHP2 reduces the mobility of VE-cadherin at recovered cell-cell junctions. In conclusion, our data show that the SHP2 phosphatase plays an important role in the recovery of disrupted endothelial cell-cell junctions by dephosphorylating VE-cadherin-associated β-catenin and promoting the mobility of VE-cadherin at the plasma membrane.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adherens Junctions / drug effects
  • Adherens Junctions / enzymology*
  • Animals
  • Antigens, CD / metabolism
  • COS Cells
  • Cadherins / metabolism
  • Chlorocebus aethiops
  • Electric Impedance
  • Endothelial Cells / cytology*
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism*
  • Enzyme Activation / drug effects
  • Gene Silencing / drug effects
  • HEK293 Cells
  • Human Umbilical Vein Endothelial Cells
  • Humans
  • Phosphorylation / drug effects
  • Phosphotyrosine / metabolism
  • Protein Tyrosine Phosphatase, Non-Receptor Type 11 / metabolism*
  • Substrate Specificity / drug effects
  • Thrombin / pharmacology
  • beta Catenin / metabolism*
  • cdc42 GTP-Binding Protein / metabolism
  • rac1 GTP-Binding Protein / metabolism
  • rhoA GTP-Binding Protein / metabolism

Substances

  • Antigens, CD
  • Cadherins
  • beta Catenin
  • cadherin 5
  • Phosphotyrosine
  • PTPN11 protein, human
  • Protein Tyrosine Phosphatase, Non-Receptor Type 11
  • Thrombin
  • cdc42 GTP-Binding Protein
  • rac1 GTP-Binding Protein
  • rhoA GTP-Binding Protein