Trans-inactivation of Receptor Tyrosine Kinases by Novel Angiotensin II AT2 Receptor-interacting Protein, ATIP

doi:10.1074/jbc.M403880200

Trans-inactivation of Receptor Tyrosine Kinases by Novel Angiotensin II AT2 Receptor-interacting Protein, ATIP*

^‡Department of Cell Biology, Institut Cochin, INSERM U567-CNRS UMR8104, 22 rue Méchain, 75014 Paris, France, the ^**University of Melbourne, Clinical Pharmacology Unit, Austin Health, Heidelberg, Australia 3084, the ^∥Department of Medical Biochemistry, Ehime University School of Medicine, Shigenobu, Onsen-gun, Ehime 791-0295, Japan, the ^§Molecular Engines Laboratories, 20 rue Bouvier, 75011 Paris, France, the ^§§Deutsches Herzzentrum München, Lazarettstrasse 60, D-80636 München, Germany, and ^¶¶Hybrigenics SA., 3-5 impasse Reille, 75014 Paris, France

∥∥ To whom correspondence should be sent: Institut Cochin, Dept. of Cell Biology, 22 rue Mechain, 75014 Paris, France. Tel.: 00-33-1-40-51-64-10; Fax: 00-33-1-40-51-64-30; E-mail: nahmias{at}cochin.inserm.fr.

Abstract

Negative regulation of mitogenic pathways is a fundamental process that remains poorly characterized. The angiotensin II AT2 receptor is a rare example of a 7-transmembrane domain receptor that negatively cross-talks with receptor tyrosine kinases to inhibit cell growth. In the present study, we report the molecular cloning of a novel protein, ATIP1 (AT2-interacting protein), which interacts with the C-terminal tail of the AT2 receptor, but not with those of other receptors such as angiotensin AT1, bradykinin BK2, and adrenergic β₂ receptor. ATIP1 defines a family of at least four members that possess the same domain of interaction with the AT2 receptor, contain a large coiled-coil region, and are able to dimerize. Ectopic expression of ATIP1 in eukaryotic cells leads to inhibition of insulin, basic fibroblast growth factor, and epidermal growth factor-induced ERK2 activation and DNA synthesis, and attenuates insulin receptor autophosphorylation, in the same way as the AT2 receptor. The inhibitory effect of ATIP1 requires expression, but not ligand activation, of the AT2 receptor and is further increased in the presence of Ang II, indicating that ATIP1 cooperates with AT2 to transinactivate receptor tyrosine kinases. Our findings therefore identify ATIP1 as a novel early component of growth inhibitory signaling cascade.

Footnotes

↵1 The abbreviations used are: Ang II, angiotensin II; bFGF, basic fibroblast growth factor; CHO, Chinese hamster ovary; EGF, epidermal growth factor; ERK, extracellular signal-regulated kinase; GPCR, G protein-coupled receptor; PDGF, platelet-derived growth factor; RTK, receptor tyrosine kinase; VSMC, vascular smooth muscle cell; ATIP-ID, AT2 receptor-interacting protein-(interacting domain); HA, hemagglutinin.
↵2 M. Di Benedetto, manuscript in preparation.
↵* This work was supported by the Centre National de la Recherche Scientifique, the Institut National de la Santé et de la Recherche Médicale, the Association pour la Recherche contre le Cancer, the Ligue Nationale Contre le Cancer, the Ligue Contre le Cancer Comité de Paris, and the Fondation pour la Recherche Médicale. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

The nucleotide sequence(s) reported in this paper has been submitted to the GenBank™/EBI Data Bank with accession number(s) AF173380 and AF293357.
↵¶ These three authors contributed equally to this work.
↵‡‡ Supported by an INSERM/NH&MRC (Australia) post-doctoral fellowship.
- Received April 7, 2004.
The American Society for Biochemistry and Molecular Biology, Inc.