Structure of the EGF receptor transactivation circuit integrates multiple signals with cell context.
Transactivation of the epidermal growth factor receptor (EGFR) is thought to be a process by which a variety of cellular inputs can be integrated into a single signaling pathway through either stimulated proteolysis (shedding) of membrane-anchored EGFR ligands or by modification of the activity of the EGFR. As a first step towards building a predictive model of the EGFR transactivation circuit, we quantitatively defined how signals from multiple agonists were integrated both upstream and downstream of the EGFR to regulate extracellular signal regulated kinase (ERK) activity in human mammary epithelial cells. By using a "non-binding" reporter of ligand shedding, we found that transactivation triggers a positive feedback loop from ERK back to the EGFR such that ligand shedding drives EGFR-stimulated ERK that in turn drives further ligand shedding. Importantly, activated Ras and ERK levels were nearly linear functions of ligand shedding and the effect of multiple, sub-saturating inputs was additive. Simulations showed that ERK-mediated feedback through ligand shedding resulted in a stable steady-state level of activated ERK, but also showed that the extracellular environment can modulate the level of feedback. Our results suggest that the transactivation circuit acts as a context-dependent integrator and amplifier of multiple extracellular signals and that signal integration can effectively occur at multiple points in the EGFR pathway.
Joslin
Elizabeth J
EJ
Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Shankaran
Harish
H
Opresko
Lee K
LK
Bollinger
Nikki
N
Lauffenburger
Douglas A
DA
Wiley
H Steven
HS
D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005419:Flavonoids / Q000494:pharmacology; D000077156:Gefitinib; D053263:Gene Regulatory Networks / Q000187:drug effects; D017228:Hepatocyte Growth Factor / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D008024:Ligands; D008246:Lysophospholipids / Q000494:pharmacology; D042361:Mammary Glands, Human / Q000166:cytology; D010766:Phosphorylation / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D011799:Quinazolines / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D015533:Transcriptional Activation / Q000187:drug effects; D016211:Transforming Growth Factor alpha / Q000494:pharmacology
D005419:Flavonoids; D007093:Imidazoles; D008024:Ligands; D008246:Lysophospholipids; D011725:Pyridines; D011799:Quinazolines; D016211:Transforming Growth Factor alpha; D017228:Hepatocyte Growth Factor; D066246:ErbB Receptors; D048049:Extracellular Signal-Regulated MAP Kinases; C093642:SB 203580; C032881:lysophosphatidic acid; D000077156:Gefitinib; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one
J Clin Invest. 2008 Nov;118(11):3574-81
18982164
Nat Cell Biol. 2007 Aug;9(8):905-14
17618274
J Biol Chem. 2000 Jul 21;275(29):22583-9
10807918
Nat Rev Mol Cell Biol. 2006 Jul;7(7):505-16
16829981
Biophys J. 2003 Jun;84(6):3624-35
12770871
Exp Cell Res. 2004 Jul 1;297(1):224-34
15194438
Am J Physiol Cell Physiol. 2002 Mar;282(3):C545-59
11832340
J Cell Sci. 2001 Jun;114(Pt 12):2301-13
11493669
J Biol Chem. 2008 Nov 14;283(46):31477-87
18782770
Exp Cell Res. 2005 Aug 15;308(2):439-45
15950968
Trends Pharmacol Sci. 1999 Oct;20(10):408-12
10577253
Science. 2008 Oct 17;322(5900):390-5
18927383
J Biol Chem. 1996 Feb 9;271(6):3279-84
8621731
Nat Cell Biol. 2006 Nov;8(11):1195-203
17060902
Proc Natl Acad Sci U S A. 1999 May 25;96(11):6235-40
10339571
Cell. 2006 Mar 24;124(6):1225-39
16564013
Tissue Eng. 1995 Spring;1(1):81-94
19877917
J Biol Chem. 1999 Oct 1;274(40):28828-35
10497257
Biochem Soc Trans. 2003 Dec;31(Pt 6):1203-8
14641026
J Biol Chem. 1999 Nov 26;274(48):34350-60
10567412
Nat Cell Biol. 2007 Mar;9(3):324-30
17310240
J Biol Chem. 1994 Dec 23;269(51):32621-5
7798267
J Cell Sci. 2005 Jun 1;118(Pt 11):2371-80
15923650
Exp Cell Res. 2003 Mar 10;284(1):2-13
12648462
Oncogene. 1997 Feb 6;14(5):623-5
9053862
J Cell Sci. 2007 Oct 15;120(Pt 20):3688-99
17895366
Am J Physiol Lung Cell Mol Physiol. 2006 Sep;291(3):L407-16
16632517
J Biol Chem. 2001 Aug 10;276(32):30475-82
11402047
Cell Signal. 2005 Oct;17(10):1183-93
15982853
Exp Cell Res. 1993 Sep;208(1):175-88
7689475
Sci STKE. 2000 Jan 18;2000(15):pe1
11865189
Mol Cell Biol. 2000 Nov;20(22):8513-25
11046147
Endocr Relat Cancer. 2001 Mar;8(1):11-31
11350724
J Proteome Res. 2008 Feb;7(2):558-69
18166007
Front Biosci. 2008 Jan 01;13:1857-65
17981673
J Cell Physiol. 2007 Dec;213(3):589-602
17786953
Biochem J. 1992 Dec 1;288 ( Pt 2):351-5
1334404
Science. 2002 May 31;296(5573):1648-9
12040181
Proc Natl Acad Sci U S A. 1989 Feb;86(4):1249-53
2919173
EMBO J. 1999 Dec 15;18(24):6962-72
10601018
Hepatology. 2008 Jul;48(1):276-88
18536058
J Cell Biol. 1998 Nov 30;143(5):1317-28
9832559
Protein Eng. 1996 Sep;9(9):781-8
8888144
J Mol Cell Cardiol. 2008 May;44(5):831-54
18430438