CARD10 is a novel caspase recruitment domain/membrane-associated guanylatekinase family member that interacts with BCL10 and activates NF-kappa B

BCL10 belongs to the caspase recruitment domain (CARD) family of proteins t hat regulate apoptosis and NF-kappaB signaling pathways. Analysis of BCL10- deficcient mice has revealed that BCL10 mediates NF-kappaB activation by an tigen receptors in B and T cells. We recently identified a subclass of CARD proteins (CARD9, CARD11, and CARD14) that may function to connect BCL10 to multiple upstream signaling pathways. We report here that CARD10 is a nove l BCL10 interactor that belongs to the membrane-associated guanylate kinase family, a class of proteins that function to organize signaling complexes at plasma membranes. When expressed in cells, CARD10 binds to BCL10 and sig nals the activation of NF-kappaB through its N-terminal effector CARD domai n. We propose that CARD10 functions as a molecular scaffold for the assembl y of a BCL10 signaling complex that activates NF-kappaB.