Cellular and Mathematical Analyses of LUBAC Involvement in T Cell Receptor-Mediated NF-κB Activation Pathway

Front Immunol. 2020 Nov 23;11:601926. doi: 10.3389/fimmu.2020.601926. eCollection 2020.

Abstract

The LUBAC ubiquitin ligase complex, composed of the HOIP, HOIL-1L, and SHARPIN subunits, stimulates the canonical nuclear factor-κB (NF-κB) activation pathways through its Met1-linked linear ubiquitination activity. Here we performed cellular and mathematical modeling analyses of the LUBAC involvement in the T cell receptor (TCR)-mediated NF-κB activation pathway, using the Jurkat human T cell line. LUBAC is indispensable for TCR-induced NF-κB and T cell activation, and transiently associates with and linearly ubiquitinates the CARMA1-BCL10-MALT1 (CBM) complex, through the catalytic HOIP subunit. In contrast, the linear ubiquitination of NEMO, a substrate of the TNF-α-induced canonical NF-κB activation pathway, was limited during the TCR pathway. Among deubiquitinases, OTULIN, but not CYLD, plays a major role in downregulating LUBAC-mediated TCR signaling. Mathematical modeling indicated that linear ubiquitination of the CBM complex accelerates the activation of IκB kinase (IKK), as compared with the activity induced by linear ubiquitination of NEMO alone. Moreover, simulations of the sequential linear ubiquitination of the CBM complex suggested that the allosteric regulation of linear (de)ubiquitination of CBM subunits is controlled by the ubiquitin-linkage lengths. These results indicated that, unlike the TNF-α-induced NF-κB activation pathway, the TCR-mediated NF-κB activation in T lymphocytes has a characteristic mechanism to induce LUBAC-mediated NF-κB activation.

Keywords: CBM complex; LUBAC; NF-κB; T cell receptor; linear ubiquitin; mathematical model.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies / pharmacology
  • B-Cell CLL-Lymphoma 10 Protein / metabolism
  • CARD Signaling Adaptor Proteins / metabolism
  • Computer Simulation
  • Deubiquitinating Enzyme CYLD / genetics
  • Deubiquitinating Enzyme CYLD / metabolism
  • Endopeptidases / genetics
  • Endopeptidases / metabolism
  • Guanylate Cyclase / metabolism
  • Humans
  • Jurkat Cells
  • Lymphocyte Activation* / drug effects
  • Models, Immunological*
  • Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein / metabolism
  • Multienzyme Complexes
  • NF-kappa B / genetics
  • NF-kappa B / metabolism*
  • Receptors, Antigen, T-Cell / metabolism*
  • Signal Transduction
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / enzymology*
  • T-Lymphocytes / immunology
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism*
  • Ubiquitination
  • Ubiquitins / genetics
  • Ubiquitins / metabolism*

Substances

  • Antibodies
  • B-Cell CLL-Lymphoma 10 Protein
  • BCL10 protein, human
  • CARD Signaling Adaptor Proteins
  • Multienzyme Complexes
  • NF-kappa B
  • Receptors, Antigen, T-Cell
  • SHARPIN protein, human
  • Transcription Factors
  • Ubiquitins
  • RBCK1 protein, human
  • RNF31 protein, human
  • Ubiquitin-Protein Ligases
  • Endopeptidases
  • OTULIN protein, human
  • CYLD protein, human
  • Deubiquitinating Enzyme CYLD
  • MALT1 protein, human
  • Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein
  • CARD11 protein, human
  • Guanylate Cyclase