title: The modular nature of apoptotic signaling proteins.
abstract: Apoptosis, initiated by a variety of stimuli, is a physiological process that engages a well-ordered signaling cascade, eventually leading to the controlled death of the cell. The most extensively studied apoptotic stimulus is the binding of death receptors related to CD95 (Fas/Apo1) by their respective ligands. During the last years, a considerable number of proteins have been identified which act together in the receptor-proximal part of the signaling pathway. Based on localized regions of sequence similarity, it has been predicted that these proteins consist of several independently folding domains. In several cases these predictions have been confirmed by structural studies; in other cases they are at least supported by experimental data. This review focuses on the three most widespread domain families found in the apoptotic signaling proteins: the death domain, the death effector domain and the caspase recruitment domain. The recently discovered analogies between these domains, both in structure and in function, have shed some light on the overall architecture of the pathway leading from death receptor ligation to the activation of caspases and eventually to the apoptotic phenotype.
authors.affiliation: MEMOREC Stoffel GmbH, Köln, Germany. Kay.Hofmann@memorec.com
authors.forename: K
authors.initials: K
authors.lastname: Hofmann
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D015703:Antigens, CD / Q000737:chemistry / Q000502:physiology; D017209:Apoptosis; D029681:Arabidopsis Proteins; D002352:Carrier Proteins / Q000737:chemistry / Q000502:physiology; D020169:Caspases / Q000378:metabolism; D004789:Enzyme Activation; D053222:Fas Ligand Protein; D053200:Fas-Associated Death Domain Protein; D044943:Fatty Acid Desaturases / Q000737:chemistry / Q000502:physiology; D015801:Helminth Proteins / Q000737:chemistry / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000502:physiology; D008969:Molecular Sequence Data; D005810:Multigene Family; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000502:physiology; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry / Q000502:physiology; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; D018124:Receptors, Tumor Necrosis Factor / Q000737:chemistry / Q000502:physiology; D047888:Receptors, Tumor Necrosis Factor, Type I; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013329:Structure-Activity Relationship; D047990:TNF Receptor-Associated Factor 1; D019014:fas Receptor / Q000737:chemistry / Q000502:physiology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D015703:Antigens, CD; D029681:Arabidopsis Proteins; D002352:Carrier Proteins; C505533:FADD protein, human; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D053200:Fas-Associated Death Domain Protein; D015801:Helminth Proteins; D008562:Membrane Glycoproteins; D011506:Proteins; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D047990:TNF Receptor-Associated Factor 1; D019014:fas Receptor; D044943:Fatty Acid Desaturases; C084083:Fad7 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; C506249:RIPK1 protein, human; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; D020169:Caspases