title: Formation of the death domain complex between FADD and RIP1 proteins in vitro.
abstract: Fas-associated death domain (FADD) protein is an adapter molecule that bridges the interactions between membrane death receptors and initiator caspases. The death receptors contain an intracellular death domain (DD) which is essential to the transduction of the apoptotic signal. The kinase receptor-interacting protein 1 (RIP1) is crucial to programmed necrosis. The cell type interplay between FADD and RIP1, which mediates both necrosis and NF-κB activation, has been evaluated in other studies, but the mechanism of the interaction of the FADD and RIP1 proteins remain poorly understood. Here, we provided evidence indicating that the DD of human FADD binds to the DD of RIP1 in vitro. We developed a molecular docking model using homology modeling based on the structures of FADD and RIP1. In addition, we found that two structure-based mutants (G109A and R114A) of the FADD DD were able to bind to the RIP1 DD, and two mutations (Q169A and N171A) of FADD DD and four mutations (G595, K596, E620, and D622) of RIP1 DD disrupted the FADD-RIP1 interaction. Six mutations (Q169A, N171A, G595, K596, E620, and D622) lowered the stability of the FADD-RIP1 complex and induced aggregation that structurally destabilized the complex, thus disrupting the interaction.
authors.affiliation: Department of Molecular Biology, College of Natural Sciences, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, Republic of Korea.
authors.forename: Young-Hoon
authors.initials: YH
authors.lastname: Park
authors.forename: Mi Suk
authors.initials: MS
authors.lastname: Jeong
authors.forename: Hyun Ho
authors.initials: HH
authors.lastname: Park
authors.forename: Se Bok
authors.initials: SB
authors.lastname: Jang
mesh_terms: D019943:Amino Acid Substitution; D053200:Fas-Associated Death Domain Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D062105:Molecular Docking Simulation; D046912:Multiprotein Complexes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D020125:Mutation, Missense; D028861:Nuclear Pore Complex Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: C119724:AGFG1 protein, human; C505533:FADD protein, human; D053200:Fas-Associated Death Domain Protein; D046912:Multiprotein Complexes; D028861:Nuclear Pore Complex Proteins; D016601:RNA-Binding Proteins