ABSTRACT
TACI, like other members of the TNFR family, such as TNFR-I and Fas, might require ligand-induced trimerization for signaling. The TRAFs that associate with TACI cytoplasmically have been shown to have a higher affinity for trimeric receptors. Therefore, in the case of mutations in the cytoplasmic domain of TACI, the recruitment of mutant and normal TACI subunits into a trimeric complex will compromise the binding of downstream signaling molecules and thus interfere with signaling. In this case, the mutant TACI will be acting as a dominant negative.
