Plays a key role in both adaptive and innate immune signaling by bridging CARD domain-containing proteins to immune activation. Acts by channeling adaptive and innate immune signaling downstream of CARD domain-containing proteins CARD9, CARD11 and CARD14 to activate NF-kappa-B and MAP kinase p38 (MAPK11, MAPK12, MAPK13 and/or MAPK14) pathways which stimulate expression of genes encoding pro-inflammatory cytokines and chemokines. Recruited by activated CARD domain-containing proteins: homooligomerized CARD domain-containing proteins form a nucleating helical template that recruits BCL10 via CARD-CARD interaction, thereby promoting polymerization of BCL10, subsequent recruitment of MALT1 and formation of a CBM complex. This leads to activation of NF-kappa-B and MAP kinase p38 (MAPK11, MAPK12, MAPK13 and/or MAPK14) pathways which stimulate expression of genes encoding pro-inflammatory cytokines and chemokines. Activated by CARD9 downstream of C-type lectin receptors; CARD9-mediated signals are essential for antifungal immunity. Activated by CARD11 downstream of T-cell receptor (TCR) and B-cell receptor (BCR). Promotes apoptosis, pro-caspase-9 maturation and activation of NF-kappa-B via NIK and IKK.