Signaling via MALT1 downstream of various receptors and CARMA/CARD proteins. CBM complexes composed of MALT1, BCL10 and the indicated CARMA/CARD proteins are formed downstream of receptors containing immunoreceptor tyrosine-based activation motifs (ITAMs), G-protein-coupled receptors (GPCRs) or receptor tyrosine kinases (RTKs). Once formed, the CBM complex activates downstream signaling events via the scaffold and protease function of MALT1. The CBM complex of T and B cells is best characterized, while CBM complexes in other cellular contexts are less well studied. Open questions that remain to be addressed are annotated with a red question mark. Deregulated activation of the pathway results in different diseases, as summarized in the lower panel of the figure. BCR, B cell receptor; DC, dendritic cell; EGFR, epidermal growth factor receptor; FcR, Fc receptor; Mφ, macrophage; MC, myeloid cell; NK, natural killer; OSCAR, osteoclast associated receptor; PKC, protein kinase C; TCR, T cell receptor; TREM-1, triggering expression by myeloid cells 1; RA, rheumatoid arthritis.