Gab2 facilitates IL-1β–induced assembly of the CBM signalosome and MALT1 interaction with TRAF6. (A) IL-1β induces the formation of the CBM signalosome. HUVECs were treated with a control vehicle or IL-1β for 5 minutes. The cell lysates were immunoprecipitated with BCL-10 antibodies, and the immunoprecipitates were probed for the presence of CARMA3, MALT1, and BCL-10 by immunoblot analysis. (B) IL-1β induces MALT1 association with TRAF6. HUVECs were treated with a control vehicle or IL-1β for 5 minutes, and the cell lysates were immunoprecipitated with TRAF6 antibodies. The immunoprecipitates were probed for the presence of MALT1 and TRAF6. (C) Gab2 silencing prevents IL-1β–induced CBM signalosome formation. HUVECs were transfected with scRNA or Gab2 siRNA (200 nM). After 48 hours, the cells were treated with a control vehicle or IL-1β for 5 minutes. The cell lysates were immunoprecipitated with BCL-10 antibodies, and the immunoprecipitates were probed for the presence of CARMA3, MALT1, and BCL-10 by immunoblot analysis. (D) Gab2 silencing abolishes IL-1β–induced MALT1 association with TRAF6. HUVECs transfected with scRNA or Gab2 siRNA were treated with a control vehicle of IL-1β for 5 minutes. The cell lysates were immunoprecipitated with TRAF6 antibodies, and the immunoprecipitates were probed for the presence of MALT1 and TRAF6. In addition, cell lysates were probed for Gab2, MALT1, and GAPDH.