Plasma membrane translocation of trimerized MLKL protein is required for TNF-induced necroptosis

Nat Cell Biol. 2014 Jan;16(1):55-65. doi: 10.1038/ncb2883. Epub 2013 Dec 8.

Abstract

The mixed lineage kinase domain-like protein (MLKL) has recently been identified as a key RIP3 (receptor interacting protein 3) downstream component of tumour necrosis factor (TNF)-induced necroptosis. MLKL is phosphorylated by RIP3 and is recruited to the necrosome through its interaction with RIP3. However, it is still unknown how MLKL mediates TNF-induced necroptosis. Here, we report that MLKL forms a homotrimer through its amino-terminal coiled-coil domain and locates to the cell plasma membrane during TNF-induced necroptosis. By generating different MLKL mutants, we demonstrated that the plasma membrane localization of trimerized MLKL is critical for mediating necroptosis. Importantly, we found that the membrane localization of MLKL is essential for Ca(2+) influx, which is an early event of TNF-induced necroptosis. Furthermore, we identified that TRPM7 (transient receptor potential melastatin related 7) is a MLKL downstream target for the mediation of Ca(2+) influx and TNF-induced necroptosis. Hence, our study reveals a crucial mechanism of MLKL-mediated TNF-induced necroptosis.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Animals
  • Apoptosis / drug effects*
  • Calcium / metabolism
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism*
  • HEK293 Cells
  • HT29 Cells
  • Humans
  • Imidazoles / pharmacology
  • Indoles / pharmacology
  • Jurkat Cells
  • Mice
  • Mutant Proteins / chemistry
  • Mutant Proteins / metabolism
  • Necrosis / pathology*
  • Protein Kinases / chemistry
  • Protein Kinases / metabolism*
  • Protein Multimerization* / drug effects
  • Protein Structure, Tertiary
  • Protein Transport / drug effects
  • Protein-Serine-Threonine Kinases
  • RNA, Small Interfering / metabolism
  • Receptor-Interacting Protein Serine-Threonine Kinases / metabolism
  • TRPM Cation Channels / metabolism
  • Tumor Necrosis Factor-alpha / pharmacology*

Substances

  • Imidazoles
  • Indoles
  • Mutant Proteins
  • RNA, Small Interfering
  • TRPM Cation Channels
  • Tumor Necrosis Factor-alpha
  • necrostatin-1
  • MLKL protein, human
  • Protein Kinases
  • Protein-Serine-Threonine Kinases
  • RIPK3 protein, human
  • Receptor-Interacting Protein Serine-Threonine Kinases
  • TRPM7 protein, human
  • Calcium