Research Article

A New Caspase-8 Isoform Caspase-8s Increased Sensitivity to Apoptosis in Jurkat Cells

Figure 4

Interaction of the caspase-8s-2DED and FADD. (a) Western blot analysis of the expression of cellular extracts from 293T cells transfected with expression constructs encoding caspase-8-2DED (24 kd, lane 1), caspase-8s-2DED (13 kd, lane 2), and FADD (28 kd, lane 3) by antiprocaspase-8 and anti-FADD antibodies, respectively. (b) 293T cells were cotransfected with expression constructs for human FADD and caspase-8-2DED, lysed and immunoprecipitated (IP) with anti-FADD polyclonal antibody and immunoblotted with antiprocaspase-8. The upper band in IP lane is rabbit IG heavy chain. 50  g total cell lysate was loaded as control (WB). (c) 293T cells were cotransfected with expression constructs for human FADD and caspase-8s-2DED, and the co-immunoprecipitation assay was done as (b). (d) 293T cells were cotransfected with expression constructs for human FADD and caspase-8s-2DED, lysed and immunoprecipitated (IP) with antiprocaspase-8 and immunoblotted with anti-FADD polyclonal antibody. NS indicates the unspecified bands; 50  g total cell lysate was loaded as control (WB).
930462.fig.004a
(a)
930462.fig.004b
(b)
930462.fig.004c
(c)
930462.fig.004d
(d)