Bcl10 controls TCR- and FcgammaR-induced actin polymerization

J Immunol. 2007 Apr 1;178(7):4373-84. doi: 10.4049/jimmunol.178.7.4373.


Bcl10 plays an essential role in the adaptive immune response, because Bcl10-deficient lymphocytes show impaired Ag receptor-induced NF-kappaB activation and cytokine production. Bcl10 is a phosphoprotein, but the physiological relevance of this posttranslational modification remains poorly defined. In this study, we report that Bcl10 is rapidly phosphorylated upon activation of human T cells by PMA/ionomycin- or anti-CD3 treatment, and identify Ser(138) as a key residue necessary for Bcl10 phosphorylation. We also show that a phosphorylation-deficient Ser(138)/Ala mutant specifically inhibits TCR-induced actin polymerization yet does not affect NF-kappaB activation. Moreover, silencing of Bcl10, but not of caspase recruitment domain-containing MAGUK protein-1 (Carma1) induces a clear defect in TCR-induced F-actin formation, cell spreading, and conjugate formation. Remarkably, Bcl10 silencing also impairs FcgammaR-induced actin polymerization and phagocytosis in human monocytes. These results point to a key role of Bcl10 in F-actin-dependent immune responses of T cells and monocytes/macrophages.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism*
  • Adaptor Proteins, Signal Transducing / antagonists & inhibitors
  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / physiology*
  • B-Cell CLL-Lymphoma 10 Protein
  • Cells, Cultured
  • Humans
  • Lymphocyte Activation
  • NF-kappa B / metabolism
  • Phagocytosis / genetics
  • Phosphorylation
  • Proto-Oncogene Proteins c-vav / metabolism
  • Receptors, Antigen, T-Cell / immunology*
  • Receptors, IgG / immunology*
  • Serine / genetics
  • Serine / metabolism
  • T-Lymphocytes / immunology*
  • cdc42 GTP-Binding Protein / metabolism
  • rac1 GTP-Binding Protein / metabolism


  • Actins
  • Adaptor Proteins, Signal Transducing
  • B-Cell CLL-Lymphoma 10 Protein
  • BCL10 protein, human
  • NF-kappa B
  • Proto-Oncogene Proteins c-vav
  • Receptors, Antigen, T-Cell
  • Receptors, IgG
  • Serine
  • cdc42 GTP-Binding Protein
  • rac1 GTP-Binding Protein