Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

Activation of a Phosphotyrosine Phosphatase by Tyrosine Phosphorylation

Wolfgang Vogel, Reiner Lammers, Jiaoti Huang and Axel Ullrich
Science
New Series, Vol. 259, No. 5101 (Mar. 12, 1993), pp. 1611-1614
Stable URL: http://www.jstor.org/stable/2880669
Page Count: 4
  • More info
  • Cite this Item
Preview not available
Preview not available

Abstract

Regulation of cell proliferation, differentiation, and metabolic homeostasis is associated with the phosphorylation and dephosphorylation of specific tyrosine residues of key regulatory proteins. The phosphotyrosine phosphatase 1D (PTP 1D) contains two amino terminally located Src homology 2 (SH2) domains and is similar to the Drosophila cork-screw gene product, which positively regulates the torso tyrosine kinase signal transduction pathway. PTP activity was found to be regulated by physical interaction with a protein tyrosine kinase. PTP 1D did not dephosphorylate receptor tyrosine kinases, despite the fact that it associated with the epidermal growth factor receptor and chimeric receptors containing the extracellular domain of the epidermal growth factor receptor and the cytoplasmic domain of either the HER2-neu, kit-SCF, or platelet-derived growth factor β (βPDGF) receptors. PTP 1D was phosphorylated on tyrosine in cells overexpressing the βPDGF receptor kinase and this tyrosine phosphorylation correlated with an enhancement of its catalytic activity. Thus, protein tyrosine kinases and phosphatases do not simply oppose each other's action; rather, they may work in concert to maintain a fine balance of effector activation needed for the regulation of cell growth and differentiation.

Page Thumbnails

  • Thumbnail: Page 
1611
    1611
  • Thumbnail: Page 
1612
    1612
  • Thumbnail: Page 
1613
    1613
  • Thumbnail: Page 
1614
    1614