EGF-dependent re-routing of vesicular recycling switches spontaneous phosphorylation suppression to EGFR signaling
Abstract
Autocatalytic activation of epidermal growth factor receptor (EGFR) coupled to dephosphorylating activity of protein tyrosine phosphatases (PTPs) ensures robust yet diverse responses to extracellular stimuli. The inevitable tradeoff of this plasticity is spontaneous receptor activation and spurious signaling. We show that a ligand-mediated switch in EGFR trafficking enables suppression of spontaneous activation while maintaining EGFR's capacity to transduce extracellular signals. Autocatalytic phosphorylation of tyrosine 845 on unliganded EGFR monomers is suppressed by vesicular recycling through perinuclear areas with high PTP1B activity. Ligand-binding results in phosphorylation of the c-Cbl docking tyrosine and ubiquitination of the receptor. This secondary signal relies on EGF-induced EGFR self-association and switches suppressive recycling to directional trafficking. The re-routing regulates EGFR signaling response by the transit-time to late endosomes where it is switched-off by high PTP1B activity. This ubiquitin-mediated switch in EGFR trafficking is a uniquely suited solution to suppress spontaneous activation while maintaining responsiveness to EGF.
Article and author information
Author details
Reviewing Editor
- Suzanne R Pfeffer, Stanford University School of Medicine, United States
Version history
- Received: October 10, 2015
- Accepted: November 25, 2015
- Accepted Manuscript published: November 26, 2015 (version 1)
- Version of Record published: January 7, 2016 (version 2)
Copyright
© 2015, Baumdick et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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