title: Necroptosis Execution Is Mediated by Plasma Membrane Nanopores Independent of Calcium.
abstract: Necroptosis is a form of regulated necrosis that results in cell death and content release after plasma membrane permeabilization. However, little is known about the molecular events responsible for the disruption of the plasma membrane. Here, we find that early increase in cytosolic calcium in TNF-induced necroptosis is mediated by treatment with a Smac mimetic via the TNF/RIP1/TAK1 survival pathway. This does not require the activation of the necrosome and is dispensable for necroptosis. Necroptosis induced by the activation of TLR3/4 pathways does not trigger early calcium flux. We also demonstrate that necroptotic plasma membrane rupture is mediated by osmotic forces and membrane pores around 4 nm in diameter. This late permeabilization step represents a hallmark in necroptosis execution that is cell and treatment independent and requires the RIP1/RIP3/MLKL core. In support of this, treatment with osmoprotectants reduces cell damage in an in vivo necroptosis model of ischemia-reperfusion injury.
authors.affiliation: Interfaculty Institute of Biochemistry, Tübingen University, 72076 Tübingen, Germany. Electronic address: uris.ros@ifib.uni-tuebingen.de.
authors.forename: Uris
authors.initials: U
authors.lastname: Ros
authors.affiliation: Interfaculty Institute of Biochemistry, Tübingen University, 72076 Tübingen, Germany.
authors.forename: Aida
authors.initials: A
authors.lastname: Peña-Blanco
authors.affiliation: Institute of Experimental Immunology, University of Zürich, 8057 Zürich, Switzerland.
authors.forename: Kay
authors.initials: K
authors.lastname: Hänggi
authors.affiliation: Department of Nephrology and Hypertension, University Hospital Schleswig-Holstein, 24105 Kiel, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kunzendorf
authors.affiliation: Department of Nephrology and Hypertension, University Hospital Schleswig-Holstein, 24105 Kiel, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Krautwald
authors.affiliation: Institute of Experimental Immunology, University of Zürich, 8057 Zürich, Switzerland.
authors.forename: W Wei-Lynn
authors.initials: WW
authors.lastname: Wong
authors.affiliation: Interfaculty Institute of Biochemistry, Tübingen University, 72076 Tübingen, Germany; Max-Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany. Electronic address: ana.garcia@uni-tuebingen.de.
authors.forename: Ana J
authors.initials: AJ
authors.lastname: García-Sáez
mesh_terms: D000818:Animals; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D032701:Biomimetics; D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D057809:HEK293 Cells; D019073:HT29 Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D020930:MAP Kinase Kinase Kinases / Q000378:metabolism; D051379:Mice; D024101:Mitochondrial Proteins / Q000378:metabolism; D041681:NIH 3T3 Cells; D058608:Nanopores; D009336:Necrosis / Q000378:metabolism*; D009995:Osmosis; D053422:Receptor-Interacting Protein Serine-Threonine Kinases / Q000378:metabolism; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology; D051196:Toll-Like Receptor 3 / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D000099151:MAP Kinase Kinase Kinase 7
chemical_list: D051017:Apoptosis Regulatory Proteins; D002118:Calcium; D047908:Intracellular Signaling Peptides and Proteins; D020930:MAP Kinase Kinase Kinases; D024101:Mitochondrial Proteins; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; D051196:Toll-Like Receptor 3; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha; D000099151:MAP Kinase Kinase Kinase 7; C412403:DIABLO protein, human; C495344:TLR3 protein, human; C495345:TLR4 protein, human
keywords: Smac mimetics; TNF; calcium signaling; membrane pores; necroptosis