iTAP, a novel iRhom interactor, controls TNF secretion by policing the stability of iRhom/TACE
Abstract
The apical inflammatory cytokine TNF regulates numerous important biological processes including inflammation and cell death, and drives inflammatory diseases. TNF secretion requires TACE (also called ADAM17), which cleaves TNF from its transmembrane tether. The trafficking of TACE to the cell surface, and stimulation of its proteolytic activity, depends on membrane proteins, called iRhoms. To delineate how the TNF/TACE/iRhom axis is regulated, we performed an immunoprecipitation/mass spectrometry screen to identify iRhom-binding proteins. This identifies a novel protein, that we name iTAP (iRhom Tail-Associated Protein) that binds to iRhoms, enhancing the cell surface stability of iRhoms and TACE, preventing their degradation in lysosomes. Depleting iTAP in primary human macrophages profoundly impaired in TNF production and tissues from iTAP KO mice exhibit a pronounced depletion in active TACE levels. Our work identifies iTAP as a physiological regulator of TNF signalling and a novel target for the control of inflammation.
Data availability
We have provided the source data for all experiments that involved quantitative analyses.
Article and author information
Author details
Funding
Worldwide Cancer Research (14-1289)
- Colin Adrain
Fundação para a Ciência e a Tecnologia (PTDC/BEX-BCM/3015/2014)
- Colin Adrain
Fundação para a Ciência e a Tecnologia (SFRH/ BPD/117216/2016)
- Miguel Cavadas
Fundação para a Ciência e a Tecnologia (91/BD/14)
- Ioanna Oikonomidi
Fundação para a Ciência e a Tecnologia (SFRH/BCC/52507/2014)
- Colin Adrain
Fundação Calouste Gulbenkian
- Colin Adrain
Seventh Framework Programme (Marie Curie Career Integration Grant (project no. 618769)
- Colin Adrain
The European Crohns and Colitis Organization
- Colin Adrain
Science Foundation Ireland (14/IA/2622)
- Seamus J Martin
European Molecular Biology Organization (Installation Grant no. 2329)
- Kvido Strisovsky
Ministry of Education, Youth and Sports of the Czech Republic (LO1302)
- Kvido Strisovsky
European Regional Development Fund (CZ.2.16/3.1.00/24016)
- Kvido Strisovsky
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Christopher G Burd, Yale School of Medicine, United States
Ethics
Animal experimentation: Experiments with mice were performed in accordance with protocols approved by the Ethics Committee of the Instituto Gulbenkian de Ciencia and the Portuguese National Entity (DGAV- Direcao Geral de Alimentacao e Veterinaria) and in accordance with the Portuguese (Decreto-Lei no. 113/2013) and European (directive 2010/63/EU) legislation related to housing, husbandry, and animal welfare.
Human subjects: Human bloods were obtained from healthy volunteers with informed consent, after review and approval by Trinity College Dublin's research ethics committee.
Version history
- Received: January 12, 2018
- Accepted: June 10, 2018
- Accepted Manuscript published: June 13, 2018 (version 1)
- Version of Record published: July 12, 2018 (version 2)
- Version of Record updated: January 23, 2019 (version 3)
Copyright
© 2018, Oikonomidi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 2,698
- views
-
- 430
- downloads
-
- 50
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Further reading
-
- Biochemistry and Chemical Biology
- Structural Biology and Molecular Biophysics
The articles in this special issue highlight how modern cellular, biochemical, biophysical and computational techniques are allowing deeper and more detailed studies of allosteric kinase regulation.
-
- Biochemistry and Chemical Biology
- Microbiology and Infectious Disease
New antimalarial drug candidates that act via novel mechanisms are urgently needed to combat malaria drug resistance. Here, we describe the multi-omic chemical validation of Plasmodium M1 alanyl metalloaminopeptidase as an attractive drug target using the selective inhibitor, MIPS2673. MIPS2673 demonstrated potent inhibition of recombinant Plasmodium falciparum (PfA-M1) and Plasmodium vivax (PvA-M1) M1 metalloaminopeptidases, with selectivity over other Plasmodium and human aminopeptidases, and displayed excellent in vitro antimalarial activity with no significant host cytotoxicity. Orthogonal label-free chemoproteomic methods based on thermal stability and limited proteolysis of whole parasite lysates revealed that MIPS2673 solely targets PfA-M1 in parasites, with limited proteolysis also enabling estimation of the binding site on PfA-M1 to within ~5 Å of that determined by X-ray crystallography. Finally, functional investigation by untargeted metabolomics demonstrated that MIPS2673 inhibits the key role of PfA-M1 in haemoglobin digestion. Combined, our unbiased multi-omic target deconvolution methods confirmed the on-target activity of MIPS2673, and validated selective inhibition of M1 alanyl metalloaminopeptidase as a promising antimalarial strategy.