3u4z: Difference between revisions
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==Crystal Structure of the Tetrahymena telomerase processivity factor Teb1 OB-B== | ==Crystal Structure of the Tetrahymena telomerase processivity factor Teb1 OB-B== | ||
<StructureSection load='3u4z' size='340' side='right' caption='[[3u4z]], [[Resolution|resolution]] 2.30Å' scene=''> | <StructureSection load='3u4z' size='340' side='right'caption='[[3u4z]], [[Resolution|resolution]] 2.30Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[3u4z]] is a 2 chain structure with sequence from [ | <table><tr><td colspan='2'>[[3u4z]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Tetth Tetth]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3U4Z OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3U4Z FirstGlance]. <br> | ||
</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3u4v|3u4v]], [[3u50|3u50]]</td></tr> | </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[3u4v|3u4v]], [[3u50|3u50]]</div></td></tr> | ||
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">TAP82 ([ | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">TAP82 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=5911 TETTH])</td></tr> | ||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=3u4z FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3u4z OCA], [https://pdbe.org/3u4z PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3u4z RCSB], [https://www.ebi.ac.uk/pdbsum/3u4z PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3u4z ProSAT]</span></td></tr> | ||
</table> | </table> | ||
<div style="background-color:#fffaf0;"> | <div style="background-color:#fffaf0;"> | ||
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</div> | </div> | ||
<div class="pdbe-citations 3u4z" style="background-color:#fffaf0;"></div> | <div class="pdbe-citations 3u4z" style="background-color:#fffaf0;"></div> | ||
==See Also== | |||
*[[Telomerase-associated protein|Telomerase-associated protein]] | |||
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: Large Structures]] | |||
[[Category: Tetth]] | [[Category: Tetth]] | ||
[[Category: Huang, J]] | [[Category: Huang, J]] | ||
Revision as of 08:58, 13 July 2022
Crystal Structure of the Tetrahymena telomerase processivity factor Teb1 OB-BCrystal Structure of the Tetrahymena telomerase processivity factor Teb1 OB-B
Structural highlights
Publication Abstract from PubMedTelomerase copies its internal RNA template to synthesize telomeric DNA repeats. Unlike other polymerases, telomerase can retain its single-stranded product through multiple rounds of template dissociation and repositioning to accomplish repeat addition processivity (RAP). Tetrahymena telomerase holoenzyme RAP depends on a subunit, Teb1, with autonomous DNA-binding activity. Sequence homology and domain modeling suggest that Teb1 is a paralog of RPA70C, the largest subunit of the single-stranded DNA-binding factor replication protein (RPA), but unlike RPA, Teb1 binds DNA with high specificity for telomeric repeats. To understand the structural basis and significance of telomeric-repeat DNA recognition by Teb1, we solved crystal structures of three proposed Teb1 DNA-binding domains and defined amino acids of each domain that contribute to DNA interaction. Our studies indicate that two central Teb1 DNA-binding oligonucleotide/oligosaccharide-binding-fold domains, Teb1A and Teb1B, achieve high affinity and selectivity of telomeric-repeat recognition by principles similar to the telomere end-capping protein POT1 (protection of telomeres 1). An additional C-terminal Teb1 oligonucleotide/oligosaccharide-binding-fold domain, Teb1C, has features shared with the RPA70 C-terminal domain including a putative direct DNA-binding surface that is critical for high-RAP activity of reconstituted holoenzyme. The Teb1C zinc ribbon motif does not contribute to DNA binding but is nonetheless required for high-RAP activity, perhaps contributing to Teb1 physical association with the remainder of the holoenzyme. Our results suggest the biological model that high-affinity DNA binding by Teb1AB recruits holoenzyme to telomeres and subsequent Teb1C-DNA association traps product in a sliding-clamp-like manner that does not require high-affinity DNA binding for high stability of enzyme-product association. Structural basis for Tetrahymena telomerase processivity factor Teb1 binding to single-stranded telomeric-repeat DNA.,Zeng Z, Min B, Huang J, Hong K, Yang Y, Collins K, Lei M Proc Natl Acad Sci U S A. 2011 Dec 20;108(51):20357-61. Epub 2011 Dec 5. PMID:22143754[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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