Recruitment of the linear ubiquitin chain assembly complex stabilizes the TNF-R1 signaling complex and is required for TNF-mediated gene induction

Mol Cell. 2009 Dec 11;36(5):831-44. doi: 10.1016/j.molcel.2009.10.013.

Abstract

TNF is a key inflammatory cytokine. Using a modified tandem affinity purification approach, we identified HOIL-1 and HOIP as functional components of the native TNF-R1 signaling complex (TNF-RSC). Together, they were shown to form a linear ubiquitin chain assembly complex (LUBAC) and to ubiquitylate NEMO. We show that LUBAC binds to ubiquitin chains of different linkage types and that its recruitment to the TNF-RSC is impaired in TRADD-, TRAF2-, and cIAP1/2- but not in RIP1- or NEMO-deficient MEFs. Furthermore, the E3 ligase activity of cIAPs, but not TRAF2, is required for HOIL-1 recruitment to the TNF-RSC. LUBAC enhances NEMO interaction with the TNF-RSC, stabilizes this protein complex, and is required for efficient TNF-induced activation of NF-kappaB and JNK, resulting in apoptosis inhibition. Finally, we demonstrate that sustained stability of the TNF-RSC requires LUBAC's enzymatic activity, thereby adding a third form of ubiquitin linkage to the triggering of TNF signaling by the TNF-RSC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Cell Line
  • GTPase-Activating Proteins / genetics
  • Gene Expression Regulation*
  • HeLa Cells
  • Humans
  • Inhibitor of Apoptosis Proteins / genetics
  • Inhibitor of Apoptosis Proteins / physiology
  • Intracellular Signaling Peptides and Proteins / genetics
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Mice
  • NF-kappa B / metabolism
  • Receptors, Tumor Necrosis Factor, Type I / metabolism*
  • Signal Transduction
  • TNF Receptor-Associated Death Domain Protein / genetics
  • TNF Receptor-Associated Factor 2 / genetics
  • TNF Receptor-Associated Factor 2 / physiology
  • Tumor Necrosis Factor-alpha / physiology*
  • U937 Cells
  • Ubiquitin / metabolism*
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / physiology

Substances

  • GTPase-Activating Proteins
  • Inhibitor of Apoptosis Proteins
  • Intracellular Signaling Peptides and Proteins
  • NEMO protein, mouse
  • NF-kappa B
  • Ralbp1 protein, mouse
  • Receptors, Tumor Necrosis Factor, Type I
  • TNF Receptor-Associated Death Domain Protein
  • TNF Receptor-Associated Factor 2
  • Tumor Necrosis Factor-alpha
  • Ubiquitin
  • Ubiquitin-Protein Ligases
  • JNK Mitogen-Activated Protein Kinases