title: Depletion of RIPK3 or MLKL blocks TNF-driven necroptosis and switches towards a delayed RIPK1 kinase-dependent apoptosis.
abstract: In human cells, the RIPK1-RIPK3-MLKL-PGAM5-Drp1 axis drives tumor necrosis factor (TNF)-induced necroptosis through mitochondrial fission, but whether this pathway is conserved among mammals is not known. To answer this question, we analyzed the presence and functionality of the reported necroptotic axis in mice. As in humans, knockdown of receptor-interacting kinase-3 (RIPK3) or mixed lineage kinase domain like (MLKL) blocks TNF-induced necroptosis in L929 fibrosarcoma cells. However, repression of either of these proteins did not protect the cells from death, but instead induced a switch from TNF-induced necroptosis to receptor-interacting kinase-1 (RIPK1) kinase-dependent apoptosis. In addition, although mitochondrial fission also occurs during TNF-induced necroptosis in L929 cells, we found that knockdown of phosphoglycerate mutase 5 (PGAM5) and dynamin 1 like protein (Drp1) did not markedly protect the cells from TNF-induced necroptosis. Depletion of Pink1, a reported interactor of both PGAM5 and Drp1, did not affect TNF-induced necroptosis. These results indicate that in these murine cells mitochondrial fission and Pink1 dependent processes, including Pink-Parkin dependent mitophagy, apparently do not promote necroptosis. Our data demonstrate that the core components of the necrosome (RIPK1, RIPK3 and MLKL) are crucial to induce TNF-dependent necroptosis both in human and in mouse cells, but the associated mechanisms may differ between the two species or cell types.
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: Q
authors.initials: Q
authors.lastname: Remijsen
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: V
authors.initials: V
authors.lastname: Goossens
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: Grootjans
authors.affiliation: Center for Molecular Medicine, Laboratory for Neurobiology and Gene Therapy, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: C
authors.initials: C
authors.lastname: Van den Haute
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Vanlangenakker
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: Y
authors.initials: Y
authors.lastname: Dondelinger
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Roelandt
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Bruggeman
authors.affiliation: Microscopy Core Facility, Inflammation Research Center, VIB/Ghent University, Ghent, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Goncalves
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: M J M
authors.initials: MJ
authors.lastname: Bertrand
authors.affiliation: Center for Molecular Medicine, Laboratory for Neurobiology and Gene Therapy, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: V
authors.initials: V
authors.lastname: Baekelandt
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Takahashi
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: T V
authors.initials: TV
authors.lastname: Berghe
authors.affiliation: 1] Inflammation Research Center, Molecular Signaling and Cell Death Unit, VIB, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Molecular Signaling and Cell Death Unit, Ghent University, Ghent, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Vandenabeele
mesh_terms: D000818:Animals; D017209:Apoptosis; D034281:Dynamins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D051379:Mice; D009336:Necrosis; D010749:Phosphoprotein Phosphatases; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D053422:Receptor-Interacting Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D048069:Tumor Necrosis Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D048069:Tumor Necrosis Factors; C570694:MLKL protein, mouse; D011494:Protein Kinases; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; C506251:Ripk1 protein, mouse; C485615:Ripk3 protein, mouse; C570696:PGAM5 protein, mouse; D010749:Phosphoprotein Phosphatases; D010744:Phosphoric Monoester Hydrolases; C486391:Dnm1l protein, mouse; D034281:Dynamins