1qtn

From Proteopedia

(Difference between revisions)

Revision as of 07:32, 6 January 2015

CRYSTAL STRUCTURE OF THE COMPLEX OF CASPASE-8 WITH THE TETRAPEPTIDE INHIBITOR ACE-IETD-ALDEHYDE

Structural highlights

1qtn is a 3 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
NonStd Res:	,
Resources:	FirstGlance, OCA, RCSB, PDBsum

Disease

[CASP8_HUMAN] Defects in CASP8 are the cause of caspase-8 deficiency (CASP8D) [MIM:607271]. CASP8D is a disorder resembling autoimmune lymphoproliferative syndrome (ALPS). It is characterized by lymphadenopathy, splenomegaly, and defective CD95-induced apoptosis of peripheral blood lymphocytes (PBLs). It leads to defects in activation of T-lymphocytes, B-lymphocytes, and natural killer cells leading to immunodeficiency characterized by recurrent sinopulmonary and herpes simplex virus infections and poor responses to immunization.^[1]

Function

[CASP8_HUMAN] Most upstream protease of the activation cascade of caspases responsible for the TNFRSF6/FAS mediated and TNFRSF1A induced cell death. Binding to the adapter molecule FADD recruits it to either receptor. The resulting aggregate called death-inducing signaling complex (DISC) performs CASP8 proteolytic activation. The active dimeric enzyme is then liberated from the DISC and free to activate downstream apoptotic proteases. Proteolytic fragments of the N-terminal propeptide (termed CAP3, CAP5 and CAP6) are likely retained in the DISC. Cleaves and activates CASP3, CASP4, CASP6, CASP7, CASP9 and CASP10. May participate in the GZMB apoptotic pathways. Cleaves ADPRT. Hydrolyzes the small-molecule substrate, Ac-Asp-Glu-Val-Asp-|-AMC. Likely target for the cowpox virus CRMA death inhibitory protein. Isoform 5, isoform 6, isoform 7 and isoform 8 lack the catalytic site and may interfere with the pro-apoptotic activity of the complex.^[2] ^[3]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

BACKGROUND: Caspases are a family of cysteine proteases that have important intracellular roles in inflammation and apoptosis. Caspase-8 activates downstream caspases which are unable to carry out autocatalytic processing and activation. Caspase-8 is designated as an initiator caspase and is believed to sit at the apex of the Fas- or TNF-mediated apoptotic cascade. In view of this role, the enzyme is an attractive target for the design of inhibitors aimed at blocking the undesirable cell death associated with a range of degenerative disorders. RESULTS: The structure of recombinant human caspase-8, covalently modified with the inhibitor acetyl-Ile-Glu-Thr-Asp-aldehyde, has been determined by X-ray crystallography to 1.2 A resolution. The asymmetric unit contains the p18-p11 heterodimer; the biologically important molecule contains two dimers. The overall fold is very similar to that of caspase-1 and caspase-3, but significant differences exist in the substrate-binding region. The structure answers questions about the enzyme-inhibitor complex that could not be explained from earlier caspase structures solved at lower resolution. CONCLUSIONS: The catalytic triad in caspase-8 comprises Cys360, His317 and the backbone carbonyl oxygen atom of Arg258, which points towards the Nepsilon atom of His317. The oxygen atom attached to the tetrahedral carbon in the thiohemiacetal group of the inhibitor is hydrogen bonded to Ndelta of His317, and is not in a region characteristic of a classical 'oxyanion hole'. The N-acetyl group of the inhibitor is in the trans configuration. The caspase-8-inhibitor structure provides the basis for understanding structure/function relationships in this important initiator of the proteolytic cascade that leads to programmed cell death.

The atomic-resolution structure of human caspase-8, a key activator of apoptosis.,Watt W, Koeplinger KA, Mildner AM, Heinrikson RL, Tomasselli AG, Watenpaugh KD Structure. 1999 Sep 15;7(9):1135-43. PMID:10508785^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Chun 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. Pleiotropic defects in lymphocyte activation caused by caspase-8 mutations lead to human immunodeficiency. Nature. 2002 Sep 26;419(6905):395-9. PMID:12353035 doi:10.1038/nature01063
↑ Himeji D, Horiuchi T, Tsukamoto H, Hayashi K, Watanabe T, Harada M. Characterization of caspase-8L: a novel isoform of caspase-8 that behaves as an inhibitor of the caspase cascade. Blood. 2002 Jun 1;99(11):4070-8. PMID:12010809
↑ Muzio M, Salvesen GS, Dixit VM. FLICE induced apoptosis in a cell-free system. Cleavage of caspase zymogens. J Biol Chem. 1997 Jan 31;272(5):2952-6. PMID:9006941
↑ Watt W, Koeplinger KA, Mildner AM, Heinrikson RL, Tomasselli AG, Watenpaugh KD. The atomic-resolution structure of human caspase-8, a key activator of apoptosis. Structure. 1999 Sep 15;7(9):1135-43. PMID:10508785

1 Structural highlights
2 Disease
3 Function
4 Evolutionary Conservation
5 Publication Abstract from PubMed
6 See Also
7 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1qtn"

@@ Line 3: / Line 3: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1qtn]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QTN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1QTN FirstGlance]. <br>
-</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=DTD:DITHIANE+DIOL'>DTD</scene><br>
+</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=DTD:DITHIANE+DIOL'>DTD</scene></td></tr>
-<tr><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</scene>, <scene name='pdbligand=ASJ:(3S)-3-AMINO-4-HYDROXYBUTANOIC+ACID'>ASJ</scene></td></tr>
+<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</scene>, <scene name='pdbligand=ASJ:(3S)-3-AMINO-4-HYDROXYBUTANOIC+ACID'>ASJ</scene></td></tr>
-<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1qtn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qtn OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1qtn RCSB], [http://www.ebi.ac.uk/pdbsum/1qtn PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1qtn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qtn OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1qtn RCSB], [http://www.ebi.ac.uk/pdbsum/1qtn PDBsum]</span></td></tr>
-<table>
+</table>
 == Disease ==
 [[http://www.uniprot.org/uniprot/CASP8_HUMAN CASP8_HUMAN]] Defects in CASP8 are the cause of caspase-8 deficiency (CASP8D) [MIM:[http://omim.org/entry/607271 607271]]. CASP8D is a disorder resembling autoimmune lymphoproliferative syndrome (ALPS). It is characterized by lymphadenopathy, splenomegaly, and defective CD95-induced apoptosis of peripheral blood lymphocytes (PBLs). It leads to defects in activation of T-lymphocytes, B-lymphocytes, and natural killer cells leading to immunodeficiency characterized by recurrent sinopulmonary and herpes simplex virus infections and poor responses to immunization.<ref>PMID:12353035</ref>
@@ Line 37: / Line 37: @@
 </StructureSection>
 [[Category: Homo sapiens]]
-[[Category: Watenpaugh, K D.]]
+[[Category: Watenpaugh, K D]]
-[[Category: Watt, W.]]
+[[Category: Watt, W]]
 [[Category: Apoptosis]]
 [[Category: Caspase]]

1qtn

From Proteopedia

Revision as of 07:32, 6 January 2015

CRYSTAL STRUCTURE OF THE COMPLEX OF CASPASE-8 WITH THE TETRAPEPTIDE INHIBITOR ACE-IETD-ALDEHYDE

Structural highlights

Disease

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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