title: DEDD and DEDD2 associate with caspase-8/10 and signal cell death.
abstract: An apoptotic signal triggered by cell surface death receptors is disseminated to intracellular compartments through protein-protein interactions mediated by conserved domains such as the death effector domain (DED). A unique family of single DED-containing proteins, including DEDD and DEDD2, is targeted to the nucleolus. However, the role of DEDD/DEDD2 in apoptosis remains less understood. Here we show that DEDD and DEDD2 are highly conserved in diverse species, and that they are potent inducers of apoptosis in various cell types. Deletion analysis indicates that both the N-terminal DED domain and the C-terminal region of DEDD2 can induce apoptosis. The cell death activity of this family appears to be related to their nuclear localization. DEDD and DEDD2 bind to two tandem DED-containing caspases, caspase -8 and -10, that are engaged by death receptors. Consistent with the nuclear localization of this family, caspase-8 translocates to the nucleus during CD95-induced apoptosis. DEDD and DEDD2 also readily associate with themselves and with each other. These results suggest that DEDD and DEDD2 may be important mediators for death receptors and that they may target caspases to the nucleus.
authors.affiliation: Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia 19104, USA.
authors.forename: Allison
authors.initials: A
authors.lastname: Alcivar
authors.forename: Shimin
authors.initials: S
authors.lastname: Hu
authors.forename: Jun
authors.initials: J
authors.lastname: Tang
authors.forename: Xiaolu
authors.initials: X
authors.lastname: Yang
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D053455:Caspase 10; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism*; D016923:Cell Death / Q000502:physiology; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D002888:Chromosomes, Human, Pair 19; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D053418:Death Domain Receptor Signaling Adaptor Proteins; D053200:Fas-Associated Death Domain Protein; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015843:Serpins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D014764:Viral Proteins; D019014:fas Receptor / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C116096:DEDD protein, human; C450835:DEDD2 protein, human; D004268:DNA-Binding Proteins; D053418:Death Domain Receptor Signaling Adaptor Proteins; C486432:Dedd protein, mouse; C505533:FADD protein, human; C505534:Fadd protein, mouse; D053200:Fas-Associated Death Domain Protein; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D011506:Proteins; D011993:Recombinant Fusion Proteins; D015843:Serpins; D014764:Viral Proteins; D019014:fas Receptor; C074641:interleukin-1beta-converting enzyme inhibitor; C505530:CASP8 protein, human; C506433:CASP9 protein, human; C505526:Casp8 protein, mouse; C506434:Casp9 protein, mouse; D053455:Caspase 10; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases; C506438:CASP10 protein, human