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2a1a

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Revision as of 07:14, 9 May 2018

PKR kinase domain-eIF2alpha Complex

Structural highlights

2a1a is a 2 chain structure with sequence from Atcc 18824 and Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
NonStd Res:
Related:	2a19
Gene:	SUI2, TIF211 (ATCC 18824), PRKR, EIF2AK2, PKR (HUMAN)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[IF2A_YEAST] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [E2AK2_HUMAN] Following activation by double-stranded RNA in the presence of ATP, the kinase becomes autophosphorylated and can catalyze the phosphorylation of the translation initiation factor EIF2S1, which leads to an inhibition of the initiation of protein synthesis. Double-stranded RNA is generated during the course of a viral infection. In addition to serine/threonine-protein kinase activity, also has tyrosine-protein kinase activity: phosphorylates CDK1 upon DNA damage. CDK1 phosphorylation triggers CDK1 polyubiquitination and subsequent proteolysis, thus leading to G2 arrest.^[1]

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

In response to binding viral double-stranded RNA byproducts within a cell, the RNA-dependent protein kinase PKR phosphorylates the alpha subunit of the translation initiation factor eIF2 on a regulatory site, Ser51. This triggers the general shutdown of protein synthesis and inhibition of viral propagation. To understand the basis for substrate recognition by and the regulation of PKR, we determined X-ray crystal structures of the catalytic domain of PKR in complex with eIF2alpha. The structures reveal that eIF2alpha binds to the C-terminal catalytic lobe while catalytic-domain dimerization is mediated by the N-terminal lobe. In addition to inducing a local unfolding of the Ser51 acceptor site in eIF2alpha, its mode of binding to PKR affords the Ser51 site full access to the catalytic cleft of PKR. The generality and implications of the structural mechanisms uncovered for PKR to the larger family of four human eIF2alpha protein kinases are discussed.

Higher-order substrate recognition of eIF2alpha by the RNA-dependent protein kinase PKR.,Dar AC, Dever TE, Sicheri F Cell. 2005 Sep 23;122(6):887-900. PMID:16179258^[2]

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

References

↑ Yoon CH, Miah MA, Kim KP, Bae YS. New Cdc2 Tyr 4 phosphorylation by dsRNA-activated protein kinase triggers Cdc2 polyubiquitination and G2 arrest under genotoxic stresses. EMBO Rep. 2010 May;11(5):393-9. doi: 10.1038/embor.2010.45. Epub 2010 Apr 16. PMID:20395957 doi:http://dx.doi.org/10.1038/embor.2010.45
↑ Dar AC, Dever TE, Sicheri F. Higher-order substrate recognition of eIF2alpha by the RNA-dependent protein kinase PKR. Cell. 2005 Sep 23;122(6):887-900. PMID:16179258 doi:10.1016/j.cell.2005.06.044

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2a1a"

@@ Line 1: / Line 1: @@
 ==PKR kinase domain-eIF2alpha Complex==
 <StructureSection load='2a1a' size='340' side='right' caption='[[2a1a]], [[Resolution|resolution]] 2.80&Aring;' scene=''>
@@ Line 6: / Line 7: @@
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2a19|2a19]]</td></tr>
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">SUI2, TIF211 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=4932 ATCC 18824]), PRKR, EIF2AK2, PKR ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</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=2a1a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2a1a OCA], [http://pdbe.org/2a1a PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2a1a RCSB], [http://www.ebi.ac.uk/pdbsum/2a1a 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=2a1a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2a1a OCA], [http://pdbe.org/2a1a PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2a1a RCSB], [http://www.ebi.ac.uk/pdbsum/2a1a PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2a1a ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 14: / Line 15: @@
 Check<jmol>
   <jmolCheckbox>
-    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/a1/2a1a_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/a1/2a1a_consurf.spt"</scriptWhenChecked>
     <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
     <text>to colour the structure by Evolutionary Conservation</text>

2a1a

From Proteopedia

Revision as of 07:14, 9 May 2018

PKR kinase domain-eIF2alpha Complex

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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