Necroptosis signalling is tuned by phosphorylation of MLKL residues outside the pseudokinase domain activation loop
- Author(s)
- Tanzer, MC; Tripaydonis, A; Webb, AI; Young, SN; Varghese, LN; Hall, C; Alexander, WS; Hildebrand, JM; Silke, J; Murphy, JM;
- Details
- Publication Year 2015-10-15,Volume 471,Issue #2,Page 255-65
- Journal Title
- Biochem J
- Publication Type
- Journal Article
- Abstract
- The pseudokinase, MLKL (mixed lineage kinase domain-like), has recently emerged as a critical component of the necroptosis cell death pathway. While it is clear that phosphorylation of the activation loop in the MLKL pseudokinase domain by the upstream protein kinase, RIPK3 (receptor interacting protein kinase-3), is crucial to trigger MLKL activation, it has remained unclear whether other phosphorylation events modulate MLKL function. By reconstituting Mlkl-/- , Ripk3-/- and Mlkl-/-Ripk3-/- cells with MLKL phospho-site mutants, we compared the function of known MLKL phosphorylation sites in regulating necroptosis with three phospho-sites that we identified by mass spectrometry, S158, S228 and S248. Expression of a phospho-mimetic S345D MLKL activation loop mutant induced stimulus-independent cell death in all knockout cells, demonstrating that RIPK3 phosphorylation of the activation loop of MLKL is sufficient to induce cell death. Cell death was also induced by S228A, S228E and S158A MLKL mutants in the absence of death stimuli, but was most profound in Mlkl -/- Ripk3-/- double knockout fibroblasts . These data reveal a potential role for RIPK3 as a suppressor of MLKL activation and indicate that phosphorylation can fine-tune the ability of MLKL to induce necroptosis.
- Publisher
- Portland Press Ltd
- Research Division(s)
- Cancer And Haematology; Systems Biology And Personalised Medicine; Cell Signalling And Cell Death
- PubMed ID
- 26283547
- Publisher's Version
- https://doi.org/10.1042/BJ20150678
- NHMRC Grants
- NHMRC/541901, NHMRC/1058190, NHMRC/1016647, NHMRC/1057888, NHMRC/1057905, NHMRC/1046010,
- ARC Grants
- ARC/FT100100100,
- Terms of Use/Rights Notice
- Refer to copyright notice on published article.
Creation Date: 2015-08-21 12:29:32
Last Modified: 2016-05-02 09:37:00