(A) MALT1, MALT1_1–781, or MALT1_R781L was expressed alone or in combination with HA-tagged TRAF6 in HEk293T cells. Lysates were immunoprecipitated with anti-MALT1 antibody then immunoblotted with anti-HA or anti-MALT1 antibody. Total cell lysates (TCL) were directly analyzed for expression of MALT1 or TRAF6 with anti-MALT1 or anti-HA antibody. (B) NF-κB reporter assay of HEk 293T cells expressing MALT1, MALT1_1–781, or MALT1_R781L alone or in combination with BCL10 was performed. (C) NF-κB reporter assay of HEk 293T cells expressing GB-GFP, GB-MALT1, GB-MALT1_1–781, or GB-MALT1_R781L was performed. NF-κB-dependent luciferase activity is shown as fold induction of vector-transfected cells and represents the mean +/- S.D. (n = 3).*:P<0.05, **:P<0.01, n.s.: not significant.