title: Endosomal endothelin-converting enzyme-1: a regulator of beta-arrestin-dependent ERK signaling.
abstract: Neuropeptide signaling at the cell surface is regulated by metalloendopeptidases, which degrade peptides in the extracellular fluid, and beta-arrestins, which interact with G protein-coupled receptors (GPCRs) to mediate desensitization. beta-Arrestins also recruit GPCRs and mitogen-activated protein kinases to endosomes to allow internalized receptors to continue signaling, but the mechanisms regulating endosomal signaling are unknown. We report that endothelin-converting enzyme-1 (ECE-1) degrades substance P (SP) in early endosomes of epithelial cells and neurons to destabilize the endosomal mitogen-activated protein kinase signalosome and terminate signaling. ECE-1 inhibition caused endosomal retention of the SP neurokinin 1 receptor, beta-arrestins, and Src, resulting in markedly sustained ERK2 activation in the cytosol and nucleus, whereas ECE-1 overexpression attenuated ERK2 activation. ECE-1 inhibition also enhanced SP-induced expression and phosphorylation of the nuclear death receptor Nur77, resulting in cell death. Thus, endosomal ECE-1 attenuates ERK2-mediated SP signaling in the nucleus to prevent cell death. We propose that agonist availability in endosomes, here regulated by ECE-1, controls beta-arrestin-dependent signaling of endocytosed GPCRs.
authors.affiliation: Departments of Surgery and Physiology, San Francisco, California 94143.
authors.forename: Graeme S
authors.initials: GS
authors.lastname: Cottrell
authors.affiliation: Departments of Surgery and Physiology, San Francisco, California 94143.
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Padilla
authors.affiliation: Departments of Surgery and Physiology, San Francisco, California 94143.
authors.forename: Silvia
authors.initials: S
authors.lastname: Amadesi
authors.affiliation: Departments of Surgery and Physiology, San Francisco, California 94143.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Poole
authors.affiliation: Departments of Surgery and Physiology, San Francisco, California 94143.
authors.forename: Jane E
authors.initials: JE
authors.lastname: Murphy
authors.affiliation: Department of Cell and Tissue Biology, University of California, San Francisco, California 94143.
authors.forename: Markus
authors.initials: M
authors.lastname: Hardt
authors.affiliation: University Hospital Mun̈ster, Department of Internal Medicine D, Albert-Schweitzer-Strasse 33, D-48149 Mun̈ster, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Roosterman
authors.affiliation: Department of Dermatology, Interdisciplinary Centre for Clinical Research, and the Ludwig Boltzmann Institute for Cell Biology and Immunobiology of the Skin, University of Mun̈ster, Von-Esmarch-Strasse 58, 48149 Mun̈ster, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Steinhoff
authors.affiliation: Departments of Surgery and Physiology, San Francisco, California 94143.
authors.forename: Nigel W
authors.initials: NW
authors.lastname: Bunnett
mesh_terms: D000818:Animals; D019390:Arrestins / Q000378:metabolism*; D016282:Aspartic Acid Endopeptidases / Q000737:chemistry* / Q000502:physiology*; D002467:Cell Nucleus / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism*; D000072396:Endothelin-Converting Enzymes; D006801:Humans; D020935:MAP Kinase Signaling System; D008297:Male; D008666:Metalloendopeptidases / Q000737:chemistry* / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D008954:Models, Biological; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D051381:Rats; D017207:Rats, Sprague-Dawley; D011987:Receptors, Steroid / Q000378:metabolism; D015398:Signal Transduction; D000071557:beta-Arrestins
chemical_list: D019390:Arrestins; D004268:DNA-Binding Proteins; C539821:NR4A1 protein, human; C539818:Nr4a1 protein, mouse; C539820:Nr4a1 protein, rat; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D011987:Receptors, Steroid; D000071557:beta-Arrestins; D019950:Mitogen-Activated Protein Kinase 1; D016282:Aspartic Acid Endopeptidases; D008666:Metalloendopeptidases; C000606923:ECE1 protein, human; C000606925:Ece1 protein, mouse; D000072396:Endothelin-Converting Enzymes