title: Endothelin-converting enzyme 1 and β-arrestins exert spatiotemporal control of substance P-induced inflammatory signals.
abstract: Although the intracellular trafficking of G protein-coupled receptors controls specific signaling events, it is unclear how the spatiotemporal control of signaling contributes to complex pathophysiological processes such as inflammation. By using bioluminescence resonance energy transfer and superresolution microscopy, we found that substance P (SP) induces the association of the neurokinin 1 receptor (NK1R) with two classes of proteins that regulate SP signaling from plasma and endosomal membranes: the scaffolding proteins β-arrestin (βARRs) 1 and 2 and the transmembrane metallopeptidases ECE-1c and ECE-1d. In HEK293 cells and non-transformed human colonocytes, we observed that G protein-coupled receptor kinase 2 and βARR1/2 terminate plasma membrane Ca(2+) signaling and initiate receptor trafficking to endosomes that is necessary for sustained activation of ERKs in the nucleus. βARRs deliver the SP-NK1R endosomes, where ECE-1 associates with the complex, degrades SP, and allows the NK1R, freed from βARRs, to recycle. Thus, both ECE-1 and βARRs mediate the resensitization of NK1R Ca(2+) signaling at the plasma membrane. Sustained exposure of colonocytes to SP activates NF-κB and stimulates IL-8 secretion. This proinflammatory signaling is unaffected by inhibition of the endosomal ERK pathway but is suppressed by ECE-1 inhibition or βARR2 knockdown. Inhibition of protein phosphatase 2A, which also contributes to sustained NK1R signaling at the plasma membrane, similarly attenuates IL-8 secretion. Thus, the primary function of βARRs and ECE-1 in SP-dependent inflammatory signaling is to promote resensitization, which allows the sustained NK1R signaling from the plasma membrane that drives inflammation.
authors.affiliation: From the Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia.
authors.forename: Dane D
authors.initials: DD
authors.lastname: Jensen
authors.affiliation: From the Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Halls
authors.affiliation: the Department of Surgery, University of California, San Francisco, California 94143.
authors.forename: Jane E
authors.initials: JE
authors.lastname: Murphy
authors.affiliation: From the Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia.
authors.forename: Meritxell
authors.initials: M
authors.lastname: Canals
authors.affiliation: the Department of Surgery, University of California, San Francisco, California 94143.
authors.forename: Fiore
authors.initials: F
authors.lastname: Cattaruzza
authors.affiliation: From the Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia, the Departments of Anatomy and Neuroscience and.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Poole
authors.affiliation: From the Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia.
authors.forename: TinaMarie
authors.initials: T
authors.lastname: Lieu
authors.affiliation: the Inflammatory Bowel Disease Research Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California, Los Angeles, California 90095.
authors.forename: Hon-Wai
authors.initials: HW
authors.lastname: Koon
authors.affiliation: the Inflammatory Bowel Disease Research Center, Division of Digestive Diseases, David Geffen School of Medicine, University of California, Los Angeles, California 90095.
authors.forename: Charalabos
authors.initials: C
authors.lastname: Pothoulakis
authors.affiliation: From the Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia, Pharmacology, University of Melbourne, Melbourne 3010, Australia, and Nigel.Bunnett@Monash.edu.
authors.forename: Nigel W
authors.initials: NW
authors.lastname: Bunnett
mesh_terms: D019390:Arrestins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D016282:Aspartic Acid Endopeptidases / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D000072396:Endothelin-Converting Enzymes; D031541:Fluorescence Resonance Energy Transfer; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D020935:MAP Kinase Signaling System; D008666:Metalloendopeptidases / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D018040:Receptors, Neurokinin-1 / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013373:Substance P / Q000378:metabolism*; D000071557:beta-Arrestins
chemical_list: D019390:Arrestins; D018836:Inflammation Mediators; D034741:RNA, Small Interfering; D043562:Receptors, G-Protein-Coupled; D018040:Receptors, Neurokinin-1; D011994:Recombinant Proteins; D000071557:beta-Arrestins; D013373:Substance P; D016282:Aspartic Acid Endopeptidases; D008666:Metalloendopeptidases; C000606923:ECE1 protein, human; D000072396:Endothelin-Converting Enzymes
keywords: Arrestins; Cell Signaling; G Protein-coupled Receptor (GPCR); Inflammation; Intracellular Trafficking; Neuropeptide; Receptor Endocytosis