Time resolved phosphoproteomics reveals scaffolding and catalysis-responsive patterns of SHP2-dependent signaling
- Harvard Medical School, United States
- Novo Nordisk Foundation and University of Copenhagen, Denmark
- Broad Institute of Harvard and MIT, United States
- Novartis Institutes for Biomedical Research, United States
Abstract
SHP2 is a protein tyrosine phosphatase that normally potentiates intracellular signaling by growth factors, antigen receptors, and some cytokines, yet is frequently mutated in human cancer. Here, we examine the role of SHP2 in the responses of breast cancer cells to EGF by monitoring phosphoproteome dynamics when SHP2 is allosterically inhibited by SHP099. The dynamics of phosphotyrosine abundance at more than 400 tyrosine residues reveal six distinct response signatures following SHP099 treatment and washout. Remarkably, in addition to newly identified substrate sites on proteins such as occludin, ARHGAP35, and PLCγ2, another class of sites shows reduced phosphotyrosine abundance upon SHP2 inhibition. Sites of decreased phospho-abundance are enriched on proteins with two nearby phosphotyrosine residues, which can be directly protected from dephosphorylation by the paired SH2 domains of SHP2 itself. These findings highlight the distinct roles of the scaffolding and catalytic activities of SHP2 in effecting a transmembrane signaling response.
Data availability
Quantitative proteomics data have been deposited in the mass spectrometry interactive virtual environment (MassIVE) database with the accession code MSV000083702. All other data generated in this study are in the manuscript and supporting files.
Article and author information
Author details
Kartik Subramanian
Stephen C Blacklow
Funding
Novartis Institutes for BioMedical Research
- Vidyasiri Vemulapalli
- Khal-Hentz Gabriel
- Jonathan LaRochelle
- Kimberley Stegmaier
- Stephen C Blacklow
National Cancer Institute (R35 CA220340)
- Stephen C Blacklow
National Heart, Lung, and Blood Institute (U54-HL127365)
- Lily A Chylek
- Peter K Sorger
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Vemulapalli 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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Time resolved phosphoproteomics reveals scaffolding and catalysis-responsive patterns of SHP2-dependent signaling
eLife 10:e64251.
https://doi.org/10.7554/eLife.64251
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