Caspase-8 is a caspase protein, encoded by the CASP8 gene. It most likely acts upon caspase-3.
CASP8orthologs have been identified in numerous mammals for which complete genome data are available. These unique orthologs are also present in birds.
The CASP8 gene encodes a member of the cysteine-aspartic acidprotease (caspase) family. Sequential activation of caspases plays a central role in the execution-phase of cell apoptosis. Caspases exist as inactive proenzymes composed of a prodomain, a large protease subunit, and a small protease subunit. Activation of caspases requires proteolytic processing at conserved internal aspartic residues to generate a heterodimeric enzyme consisting of the large and small subunits. This protein is involved in the programmed cell death induced by Fas and various apoptotic stimuli. The N-terminal FADD-like death effector domain of this protein suggests that it may interact with Fas-interacting protein FADD. This protein was detected in the insoluble fraction of the affected brain region from Huntington disease patients but not in those from normal controls, which implicated the role in neurodegenerative diseases. Many alternatively spliced transcript variants encoding different isoforms have been described, although not all variants have had their full-length sequences determined.
The clinical phenotype of CEDS patients represented a paradox since caspase-8 was considered to be chiefly a proapoptoticprotease, that was mainly involved in signal transduction from Tumor necrosis factor receptor family death receptors such as Fas. The defect in lymphocyte activation and protective immunity suggested that caspase-8 had additional signaling roles in lymphocytes. Further work revealed that caspase-8 was essential for the induction of the transcription factor “nuclear factor κB” (NF-κB) after stimulation through antigen receptors, Fc receptors, or Toll-like receptor 4 in T, B, and natural killer cells.
Biochemically, caspase-8 was found to enter the complex of the inhibitor of NF-κBkinase (IKK) with the upstream Bcl10-MALT1 (mucosa-associated lymphatic tissue) adapter complex which were crucial for the induction of nuclear translocation of NF-κB. Moreover, the biochemical form of caspase-8 differed in the two pathways. For the death pathway, the caspase-8 zymogen is cleaved into subunits that assemble to form the mature, highly active caspase heterotetramer whereas for the activation pathway, the zymogen appears to remain intact perhaps to limit its proteolytic function but enhance its capability as an adapter protein.
^ abcChun HJ, Zheng L, Ahmad M, Wang J, Speirs CK, Siegel RM, Dale JK, Puck J, Davis J, Hall CG, Skoda-Smith S, Atkinson TP, Straus SE, Lenardo MJ (2002). "Pleiotropic defects in lymphocyte activation caused by caspase-8 mutations lead to human immunodeficiency". Nature. 419 (6905): 395–9. doi:10.1038/nature01063. PMID12353035.
^ abcdefGajate C, Mollinedo F (March 2005). "Cytoskeleton-mediated death receptor and ligand concentration in lipid rafts forms apoptosis-promoting clusters in cancer chemotherapy". J. Biol. Chem. 280 (12): 11641–7. doi:10.1074/jbc.M411781200. PMID15659383.
^ abcdefghGuo Y, Srinivasula SM, Druilhe A, Fernandes-Alnemri T, Alnemri ES (April 2002). "Caspase-2 induces apoptosis by releasing proapoptotic proteins from mitochondria". J. Biol. Chem. 277 (16): 13430–7. doi:10.1074/jbc.M108029200. PMID11832478.
^Poulaki V, Mitsiades N, Romero ME, Tsokos M (June 2001). "Fas-mediated apoptosis in neuroblastoma requires mitochondrial activation and is inhibited by FLICE inhibitor protein and Bcl-2". Cancer Res. 61 (12): 4864–72. PMID11406564.
^Goltsev YV, Kovalenko AV, Arnold E, Varfolomeev EE, Brodianskii VM, Wallach D (August 1997). "CASH, a novel caspase homologue with death effector domains". J. Biol. Chem. 272 (32): 19641–4. doi:10.1074/jbc.272.32.19641. PMID9289491.
^ abSrinivasula SM, Ahmad M, Ottilie S, Bullrich F, Banks S, Wang Y, Fernandes-Alnemri T, Croce CM, Litwack G, Tomaselli KJ, Armstrong RC, Alnemri ES (July 1997). "FLAME-1, a novel FADD-like anti-apoptotic molecule that regulates Fas/TNFR1-induced apoptosis". J. Biol. Chem. 272 (30): 18542–5. doi:10.1074/jbc.272.30.18542. PMID9228018.
^Micheau O, Thome M, Schneider P, Holler N, Tschopp J, Nicholson DW, Briand C, Grütter MG (November 2002). "The long form of FLIP is an activator of caspase-8 at the Fas death-inducing signaling complex". J. Biol. Chem. 277 (47): 45162–71. doi:10.1074/jbc.M206882200. PMID12215447.
^Roth W, Stenner-Liewen F, Pawlowski K, Godzik A, Reed JC (March 2002). "Identification and characterization of DEDD2, a death effector domain-containing protein". J. Biol. Chem. 277 (9): 7501–8. doi:10.1074/jbc.M110749200. PMID11741985.
^Cowling V, Downward J (October 2002). "Caspase-6 is the direct activator of caspase-8 in the cytochrome c-induced apoptosis pathway: absolute requirement for removal of caspase-6 prodomain". Cell Death Differ. 9 (10): 1046–56. doi:10.1038/sj.cdd.4401065. PMID12232792.
^Zhan Y, Hegde R, Srinivasula SM, Fernandes-Alnemri T, Alnemri ES (April 2002). "Death effector domain-containing proteins DEDD and FLAME-3 form nuclear complexes with the TFIIIC102 subunit of human transcription factor IIIC". Cell Death Differ. 9 (4): 439–47. doi:10.1038/sj.cdd.4401038. PMID11965497.
^Henshall DC, Araki T, Schindler CK, Shinoda S, Lan JQ, Simon RP (September 2003). "Expression of death-associated protein kinase and recruitment to the tumor necrosis factor signaling pathway following brief seizures". J. Neurochem. 86 (5): 1260–70. doi:10.1046/j.1471-4159.2003.01934.x. PMID12911633.
^Boldin MP, Goncharov TM, Goltsev YV, Wallach D (June 1996). "Involvement of MACH, a novel MORT1/FADD-interacting protease, in Fas/APO-1- and TNF receptor-induced cell death". Cell. 85 (6): 803–15. doi:10.1016/s0092-8674(00)81265-9. PMID8681376.
^Thomas LR, Stillman DJ, Thorburn A (September 2002). "Regulation of Fas-associated death domain interactions by the death effector domain identified by a modified reverse two-hybrid screen". J. Biol. Chem. 277 (37): 34343–8. doi:10.1074/jbc.M204169200. PMID12107169.
^ abMacFarlane M, Ahmad M, Srinivasula SM, Fernandes-Alnemri T, Cohen GM, Alnemri ES (October 1997). "Identification and molecular cloning of two novel receptors for the cytotoxic ligand TRAIL". J. Biol. Chem. 272 (41): 25417–20. doi:10.1074/jbc.272.41.25417. PMID9325248.
^Gervais FG, Singaraja R, Xanthoudakis S, Gutekunst CA, Leavitt BR, Metzler M, Hackam AS, Tam J, Vaillancourt JP, Houtzager V, Rasper DM, Roy S, Hayden MR, Nicholson DW (February 2002). "Recruitment and activation of caspase-8 by the Huntingtin-interacting protein Hip-1 and a novel partner Hippi". Nat. Cell Biol. 4 (2): 95–105. doi:10.1038/ncb735. PMID11788820.
^Kitsberg D, Formstecher E, Fauquet M, Kubes M, Cordier J, Canton B, Pan G, Rolli M, Glowinski J, Chneiweiss H (October 1999). "Knock-out of the neural death effector domain protein PEA-15 demonstrates that its expression protects astrocytes from TNFalpha-induced apoptosis". J. Neurosci. 19 (19): 8244–51. PMID10493725.
^Condorelli G, Vigliotta G, Cafieri A, Trencia A, Andalò P, Oriente F, Miele C, Caruso M, Formisano P, Beguinot F (August 1999). "PED/PEA-15: an anti-apoptotic molecule that regulates FAS/TNFR1-induced apoptosis". Oncogene. 18 (31): 4409–15. doi:10.1038/sj.onc.1202831. PMID10442631.
^Chaudhary PM, Eby MT, Jasmin A, Kumar A, Liu L, Hood L (September 2000). "Activation of the NF-kappaB pathway by caspase 8 and its homologs". Oncogene. 19 (39): 4451–60. doi:10.1038/sj.onc.1203812. PMID11002417.
^Bertrand MJ, Milutinovic S, Dickson KM, Ho WC, Boudreault A, Durkin J, Gillard JW, Jaquith JB, Morris SJ, Barker PA (June 2008). "cIAP1 and cIAP2 facilitate cancer cell survival by functioning as E3 ligases that promote RIP1 ubiquitination". Mol. Cell. 30 (6): 689–700. doi:10.1016/j.molcel.2008.05.014. PMID18570872.
^Leo E, Deveraux QL, Buchholtz C, Welsh K, Matsuzawa S, Stennicke HR, Salvesen GS, Reed JC (March 2001). "TRAF1 is a substrate of caspases activated during tumor necrosis factor receptor-alpha-induced apoptosis". J. Biol. Chem. 276 (11): 8087–93. doi:10.1074/jbc.M009450200. PMID11098060.
Gupta S (2002). "Tumor necrosis factor-alpha-induced apoptosis in T cells from aged humans: a role of TNFR-I and downstream signaling molecules". Exp. Gerontol. 37 (2–3): 293–9. doi:10.1016/S0531-5565(01)00195-4. PMID11772515.
Zhao LJ, Zhu H (2005). "Structure and function of HIV-1 auxiliary regulatory protein Vpr: novel clues to drug design". Curr. Drug Targets Immune Endocr. Metabol. Disord. 4 (4): 265–75. doi:10.2174/1568008043339668. PMID15578977.