title: Complement membrane attack complexes activate noncanonical NF-κB by forming an Akt+ NIK+ signalosome on Rab5+ endosomes.
abstract: Complement membrane attack complexes (MACs) promote inflammatory functions in endothelial cells (ECs) by stabilizing NF-κB-inducing kinase (NIK) and activating noncanonical NF-κB signaling. Here we report a novel endosome-based signaling complex induced by MACs to stabilize NIK. We found that, in contrast to cytokine-mediated activation, NIK stabilization by MACs did not involve cIAP2 or TRAF3. Informed by a genome-wide siRNA screen, instead this response required internalization of MACs in a clathrin-, AP2-, and dynamin-dependent manner into Rab5(+)endosomes, which recruited activated Akt, stabilized NIK, and led to phosphorylation of IκB kinase (IKK)-α. Active Rab5 was required for recruitment of activated Akt to MAC(+) endosomes, but not for MAC internalization or for Akt activation. Consistent with these in vitro observations, MAC internalization occurred in human coronary ECs in vivo and was similarly required for NIK stabilization and EC activation. We conclude that MACs activate noncanonical NF-κB by forming a novel Akt(+)NIK(+) signalosome on Rab5(+) endosomes.
authors.affiliation: Division of Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Dan
authors.initials: D
authors.lastname: Jane-wit
authors.affiliation: Yale Center for Molecular Discovery, Yale University, New Haven, CT 06516;
authors.forename: Yulia V
authors.initials: YV
authors.lastname: Surovtseva
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Lingfeng
authors.initials: L
authors.lastname: Qin
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Guangxin
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Rebecca
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Pamela
authors.initials: P
authors.lastname: Clark
authors.affiliation: Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Manes
authors.affiliation: Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT 06520.
authors.forename: Michael
authors.initials: M
authors.lastname: Kashgarian
authors.affiliation: Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: Nancy C
authors.initials: NC
authors.lastname: Kirkiles-Smith
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT 06520;
authors.forename: George
authors.initials: G
authors.lastname: Tellides
authors.affiliation: Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520; Department of Pathology, Yale University School of Medicine, New Haven, CT 06520 jordan.pober@yale.edu.
authors.forename: Jordan S
authors.initials: JS
authors.lastname: Pober
mesh_terms: D000818:Animals; D000075747:Baculoviral IAP Repeat-Containing 3 Protein; D002966:Clathrin / Q000378:metabolism; D015938:Complement Membrane Attack Complex / Q000378:metabolism*; D003331:Coronary Vessels / Q000187:drug effects / Q000378:metabolism; D004705:Endocytosis / Q000187:drug effects; D011992:Endosomes / Q000187:drug effects / Q000378:metabolism*; D004795:Enzyme Stability / Q000187:drug effects; D005434:Flow Cytometry; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D006835:Hydrazones / Q000494:pharmacology; D051034:Inhibitor of Apoptosis Proteins / Q000378:metabolism; D016513:Mice, SCID; D016328:NF-kappa B / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D022142:Secretory Vesicles / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D048008:TNF Receptor-Associated Factor 3 / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism; D020696:rab5 GTP-Binding Proteins / Q000378:metabolism*; D000097782:NF-kappaB-Inducing Kinase
chemical_list: D000075747:Baculoviral IAP Repeat-Containing 3 Protein; D002966:Clathrin; D015938:Complement Membrane Attack Complex; D006835:Hydrazones; D051034:Inhibitor of Apoptosis Proteins; D016328:NF-kappa B; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D034741:RNA, Small Interfering; D048008:TNF Receptor-Associated Factor 3; D044767:Ubiquitin-Protein Ligases; D020696:rab5 GTP-Binding Proteins; D000097782:NF-kappaB-Inducing Kinase; C511794:N'-(3,4-dihydroxybenzylidene)-3-hydroxy-2-naphthahydrazide; C494832:BIRC3 protein, human
keywords: complement; endothelial cell; inflammation; membrane attack complex; signaling