The death-effector domain (DED) is a protein interaction domain found to regulate a variety of cellular signalling pathways. The DED domain is found in inactive procaspases (cysteine proteases) and proteins that regulate caspase activation in the apoptosis cascade such as FAS-associating death domain-containing protein (FADD). FADD recruits procaspase 8 and procaspase 10 into a death induced signaling complex (DISC). This recruitment is mediated by a homotypic interaction between the procaspase DED and a second DED that is death effector domain in an adaptor protein that is directly associated with activated TNF receptors. Complex formation allows proteolytic activation of procaspase into the active caspase form which results in the initiation of apoptosis (cell death). Structurally the DED domain are a subclass of protein motif known as the death fold and contains 6 alpha helices, that closely resemble the structure of the Death domain.
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