Wordprocessing

Systems-level interactions between insulin-EGF networks amplify mitogenic signaling

Abstract:

Crosstalk mechanisms have not been studied as thoroughly as individual signaling pathways. We exploit experimental and computational approaches to reveal how a concordant interplay between the insulin and epidermal growth factor (EGF) signaling networks can potentiate mitogenic signaling. In HEK293 cells, insulin is a poor activator of the Ras/ERK (extracellular signal-regulated kinase) cascade, yet it enhances ERK activation by low EGF doses. We find that major crosstalk mechanisms that amplify ERK signaling are localized upstream of Ras and at the Ras/Raf level. Computational modeling unveils how critical network nodes, the adaptor proteins GAB1 and insulin receptor substrate (IRS), Src kinase, and phosphatase SHP2, convert insulin-induced increase in the phosphatidylinositol-3,4,5-triphosphate (PIP(3)) concentration into enhanced Ras/ERK activity. The model predicts and experiments confirm that insulin-induced amplification of mitogenic signaling is abolished by disrupting PIP(3)-mediated positive feedback via GAB1 and IRS. We demonstrate that GAB1 behaves as a non-linear amplifier of mitogenic responses and insulin endows EGF signaling with robustness to GAB1 suppression. Our results show the feasibility of using computational models to identify key target combinations and predict complex cellular responses to a mixture of external cues.

19357636

Projects: HepatoSys

Mol. Syst. Biol.
Mol. Syst. Biol. 5: 256
7th Apr 2009

Nikolay Borisov, Edita Aksamitiene, Anatoly Kiyatkin, Stefan Legewie, Jan Berkhout, Thomas Maiwald, Nikolai P Kaimachnikov, Jens Timmer, Jan B Hoek, Boris N Kholodenko

help Authors

[Stefan Legewie] [Thomas Maiwald] [Jens Timmer]

help Attributions

None

help Scales


Not Specified
Views: 2122
  • Created: 11th Sep 2012 at 11:41
  • Last updated: 24th Oct 2013 at 16:21

Related items

Ajax-loader-large

Log in / Register

Need an account?
Sign up

Forgotten password?

Front Page

Virtual Liver Network

(v.0.22.0)

Related Projects and friends


Imprint Taverna workflow workbench myExperiment JWS Online ISATAB myGrid Sabio-RK BioPortal Semantic SBML

Powered by:

Ror-logo-32

Icons:
Silk icons 1.3
Crystal Clear icons