Figure 4

SMs fail to stimulate degradation of cIAP2-MALT1. (a) Wild-type cIAP2, but not the RING-finger mutants cIAP2^ΔRING, cIAP2^V568E and cIAP2^L585A/I590A, is degraded by LBW242. cIAP2^ΔRING lacks the C-terminal RING-finger domain, whereas cIAP2^V568E and cIAP2^L585A/I590A carry point mutations that abrogate RING dimerisation and E2 binding, respectively. HEK293T cells were transiently transfected with plasmids expressing the indicated constructs. After 24 h, cells were either left untreated or incubated with 1 μM LBW242. (b) Schematic representation of the constructs used. (c) HEK293T cells were transiently transfected with plasmids expressing FLAG-cIAP2-MALT1 or FLAG-cIAP2^N−Term (amino acids 1–442). The experiment was conducted as described in a. (d) Expression of cIAP2-MALT1 induces NF-κB activation that is resistant to SM intervention. cIAP2-MALT1 was co-transfected with a NF-κB reporter plasmid in HEK293T cells. Luciferase activity was expressed relative to untreated controls. Data represent the mean of three independent experiments, and the error bars indicate S.D. of triplicates