The solution structure of FADD death domain - Structural basis of death domain interactions of Fas and FADD

Abstract

A signal of Pas-mediated apoptosis is transferred through an adaptor protein Pas-associated death domain protein (FADD) by interactions between the death domains of Pas and FADD. To understand the signal transduction mechanism of Pas-mediated apoptosis, we solved the solution structure of a murine FADD death domain. It consists of six helices arranged in a similar fold to the other death domains. The interactions between the death domains of Pas and FADD analyzed by site-directed mutagenesis indicate that charged residues in helices alpha 2 and alpha 3 are involved in death domain interactions, and the interacting helices appear to interact in anti-parallel pattern, alpha 2 of FADD with alpha 3 of Fas and vice versa.