Dataset Information

Early Signaling Dynamics of EGFR

ABSTRACT: Despite extensive study of the epidermal growth factor receptor (EGFR) signaling network, the immediate post-translational changes that occur in response to growth factor stimulation remain poorly characterized; as a result, the biological mechanisms underlying signaling initiation remain obscured. To address this deficiency, we have used a mass spectrometry-based approach to measure system-wide phosphorylation changes throughout the network with 10 second resolution in the 80 seconds after stimulation in response to a range of 8 growth factor concentrations. Significant changes were observed on proteins far downstream in the network as early as 10 seconds after stimulation, indicating a system capable of transmitting information quickly. Meanwhile, canonical members of the EGFR signaling network fall into clusters with distinct activation patterns. Shc and PI3K phosphorylation levels increase rapidly, but equilibrate within 20 s, while proteins like Gab1 and SHP2 show slower, sustained increases. Proximity ligation assays reveal that Shc and Gab1 phosphorylation patterns are representative of separate timescales for physical association with the receptor. Inhibition of phosphatases with vanadate reveals site-specific regulatory mechanisms, and also uncovers primed activating components in the network, including Src family kinases, whose inhibition impacts only a subset of proteins within the network. The results presented highlight the complexity of signaling initiation, and provide a window into exploring mechanistic hypotheses about RTK biology.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Epithelial Cell, Cell Culture

SUBMITTER: Raven Reddy

LAB HEAD: Forest White

PROVIDER: PXD003660 | Pride | 2016-06-24

REPOSITORIES: Pride

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Dataset's files

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			Action	DRS
	20140524_MCF10A_E20VR1_ETP_TMT10.raw	Raw
	20140525_MCF10A_E20VR2_ETP_TMT10.raw	Raw
	20140526_MCF10A_E20VR3_ETP_TMT10.raw	Raw
	20140528_MCF10A_E100R1_ETP_TMT10.raw	Raw
	20140528_MCF10A_E1R1_ETP_TMT10.raw	Raw

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Publications

Early signaling dynamics of the epidermal growth factor receptor.

Reddy Raven J RJ Gajadhar Aaron S AS Swenson Eric J EJ Rothenberg Daniel A DA Curran Timothy G TG White Forest M FM

Proceedings of the National Academy of Sciences of the United States of America 20160229 11

Despite extensive study of the EGF receptor (EGFR) signaling network, the immediate posttranslational changes that occur in response to growth factor stimulation remain poorly characterized; as a result, the biological mechanisms underlying signaling initiation remain obscured. To address this deficiency, we have used a mass spectrometry-based approach to measure system-wide phosphorylation changes throughout the network with 10-s resolution in the 80 s after stimulation in response to a range o ...[more]

PMID: 26929352

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