BbtCaspase-1/2 co-localized with bbtFADD2 in nucleus. (A) Comparison of the domains of bbtCaspase-1/2 with those of hsCaspase-2. Designations and structures of bbtCaspase-1/2 mutant fusion proteins used in this study. (B) Analysis of the subcelluar localization of bbtCaspase-1/2-GFP and several truncated mutants. (C) Overexpression of bbtCaspase-1/2 and the mutants containing the DD results in their co-localiztion with bbtFADD2 in the nucleus.