Fig. 5.

Caspase-8 modulates TRAF2 polyubiquitination (a and b) independent of its caspase activity (c). a, HEK293T cells were co-transfected with TRAF2, caspase-8 and WT or mutant Ub plasmid as indicated. b, HEK293T cells were co-transfected with caspase-8 siRNA and plasmids carrying the indicated genes. c, HEK293T cells were co-transfected with Flag-TRAF2 and other indicated genes or siRNAs. After 34 h of the above transfections, whole-cell protein lysates were prepared from these cells and subjected to IP and subsequent Western blotting (WB) for the indicated proteins