The DED structure consists of six antiparallel alpha-helices. The figure shows the death effector domain of a mutant FADD protein. Similar to the CARDs, the DED recruits procaspases into complexes with members of the TNF-receptor superfamily. This recruitment is mediated by a homotypic interaction between the procaspase DED and a second DED in an adaptor molecule that is directly associated with activated TNF receptors.
Complex formation allows transprocessing of procaspase to the active form.
This, in turn, activates downstream caspases and initiates apoptosis.