Report

Imaging Sites of Receptor Dephosphorylation by PTP1B on the Surface of the Endoplasmic Reticulum

+ See all authors and affiliations

Science  01 Mar 2002:
Vol. 295, Issue 5560, pp. 1708-1711
DOI: 10.1126/science.1067566

You are currently viewing the abstract.

View Full Text

Via your Institution

Log in through your institution

Log in through your institution


Abstract

When bound by extracellular ligands, receptor tyrosine kinases (RTKs) on the cell surface transmit critical signals to the cell interior. Although signal termination is less well understood, protein tyrosine phosphatase–1B (PTP1B) is implicated in the dephosphorylation and inactivation of several RTKs. However, PTP1B resides on the cytoplasmic surface of the endoplasmic reticulum (ER), so how and when it accesses RTKs has been unclear. Using fluorescence resonance energy transfer (FRET) methods, we monitored interactions between the epidermal- and platelet-derived growth factor receptors and PTP1B. PTP1B-catalyzed dephosphorylation required endocytosis of the receptors and occurred at specific sites on the surface of the ER. Most of the RTKs activated at the cell surface showed interaction with PTP1B after internalization, establishing that RTK activation and inactivation are spatially and temporally partitioned within cells.

  • * To whom correspondence should be addressed. E-mail: bneel{at}caregroup.harvard.edu (B.G.N.), bastiaen{at}embl-heidelberg.de(P.I.H.B.)

View Full Text

Related Content