This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.


Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


4ebe

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Current revision (14:57, 14 March 2024) (edit) (undo)
 
Line 4: Line 4:
== Structural highlights ==
== Structural highlights ==
<table><tr><td colspan='2'>[[4ebe]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4EBE OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4EBE FirstGlance]. <br>
<table><tr><td colspan='2'>[[4ebe]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4EBE OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4EBE FirstGlance]. <br>
-
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene>, <scene name='pdbligand=DTP:2-DEOXYADENOSINE+5-TRIPHOSPHATE'>DTP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene></td></tr>
+
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.1&#8491;</td></tr>
 +
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene>, <scene name='pdbligand=DTP:2-DEOXYADENOSINE+5-TRIPHOSPHATE'>DTP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4ebe FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ebe OCA], [https://pdbe.org/4ebe PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ebe RCSB], [https://www.ebi.ac.uk/pdbsum/4ebe PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ebe ProSAT]</span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4ebe FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ebe OCA], [https://pdbe.org/4ebe PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ebe RCSB], [https://www.ebi.ac.uk/pdbsum/4ebe PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ebe ProSAT]</span></td></tr>
</table>
</table>
== Function ==
== Function ==
-
[[https://www.uniprot.org/uniprot/POLI_HUMAN POLI_HUMAN]] Error-prone DNA polymerase specifically involved in DNA repair. Plays an important role in translesion synthesis, where the normal high-fidelity DNA polymerases cannot proceed and DNA synthesis stalls. Favors Hoogsteen base-pairing in the active site. Inserts the correct base with high-fidelity opposite an adenosine template. Exhibits low fidelity and efficiency opposite a thymidine template, where it will preferentially insert guanosine. May play a role in hypermutation of immunogobulin genes. Forms a Schiff base with 5'-deoxyribose phosphate at abasic sites, but may not have lyase activity.<ref>PMID:11013228</ref> <ref>PMID:11251121</ref> <ref>PMID:11387224</ref> <ref>PMID:12410315</ref> <ref>PMID:14630940</ref> <ref>PMID:15199127</ref> <ref>PMID:15254543</ref>
+
[https://www.uniprot.org/uniprot/POLI_HUMAN POLI_HUMAN] Error-prone DNA polymerase specifically involved in DNA repair. Plays an important role in translesion synthesis, where the normal high-fidelity DNA polymerases cannot proceed and DNA synthesis stalls. Favors Hoogsteen base-pairing in the active site. Inserts the correct base with high-fidelity opposite an adenosine template. Exhibits low fidelity and efficiency opposite a thymidine template, where it will preferentially insert guanosine. May play a role in hypermutation of immunogobulin genes. Forms a Schiff base with 5'-deoxyribose phosphate at abasic sites, but may not have lyase activity.<ref>PMID:11013228</ref> <ref>PMID:11251121</ref> <ref>PMID:11387224</ref> <ref>PMID:12410315</ref> <ref>PMID:14630940</ref> <ref>PMID:15199127</ref> <ref>PMID:15254543</ref>
-
<div style="background-color:#fffaf0;">
+
-
== Publication Abstract from PubMed ==
+
-
Y-family DNA polymerases participate in replication stress and DNA damage tolerance mechanisms. The properties that allow these enzymes to copy past bulky adducts or distorted template DNA can result in a greater propensity for them to make mistakes. Of the four human Y-family members, human DNA polymerase iota (hpol iota) is the most error-prone. In the current study, we elucidate the molecular basis for improving the fidelity of hpol iota through use of the fixed-conformation nucleotide North-methanocarba-2'-deoxyadenosine triphosphate (N-MC-dATP). Three crystal structures were solved of hpol iota in complex with DNA containing a template 2'-deoxythymidine (dT) paired with an incoming dNTP or modified nucleotide triphosphate. The ternary complex of hpol iota inserting N-MC-dATP opposite dT reveals that the adenine ring is stabilized in the anti orientation about the pseudo-glycosyl torsion angle (chi), which mimics precisely the mutagenic arrangement of dGTP:dT normally preferred by hpol iota. The stabilized anti conformation occurs without notable contacts from the protein but likely results from constraints imposed by the bicyclo[3.1.0]hexane scaffold of the modified nucleotide. Unmodified dATP and South-MC-dATP each adopt syn glycosyl orientations to form Hoogsteen base pairs with dT. The Hoogsteen orientation exhibits weaker base stacking interactions and is less catalytically favorable than anti N-MC-dATP. Thus, N-MC-dATP corrects the error-prone nature of hpol iota by preventing the Hoog-steen base-pairing mode normally observed for hpol iota-catalyzed insertion of dATP opposite dT. These results provide a previously unrecognized means of altering the efficiency and the fidelity of a human translesion DNA polymerase.
+
-
A nucleotide analogue induced gain of function corrects the error-prone nature of human DNA polymerase iota.,Ketkar A, Zafar MK, Banerjee S, Marquez VE, Egli M, Eoff RL J Am Chem Soc. 2012 May 26. PMID:22632140<ref>PMID:22632140</ref>
+
==See Also==
-
 
+
*[[DNA polymerase 3D structures|DNA polymerase 3D structures]]
-
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
+
-
</div>
+
-
<div class="pdbe-citations 4ebe" style="background-color:#fffaf0;"></div>
+
== References ==
== References ==
<references/>
<references/>

Current revision

Conformationally Restrained North-methanocarba-2'-deoxyadenosine Corrects the Error-Prone Nature of Human DNA Polymerase Iota

PDB ID 4ebe

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools