View source for 4rdx


==Strucutre of histidinyl-tRNA synthetase in complex with tRNA(His)==
<StructureSection load='4rdx' size='340' side='right' caption='[[4rdx]], [[Resolution|resolution]] 2.55&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4rdx]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4RDX OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4RDX FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=AMP:ADENOSINE+MONOPHOSPHATE'>AMP</scene>, <scene name='pdbligand=HIS:HISTIDINE'>HIS</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=GTP:GUANOSINE-5-TRIPHOSPHATE'>GTP</scene></td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Histidine--tRNA_ligase Histidine--tRNA ligase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.1.1.21 6.1.1.21] </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=4rdx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4rdx OCA], [http://pdbe.org/4rdx PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4rdx RCSB], [http://www.ebi.ac.uk/pdbsum/4rdx PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4rdx ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Aminoacyl-tRNA synthetases (aaRSs) play a crucial role in protein translation by linking tRNAs with cognate amino acids. Among all the tRNAs, only tRNA(His) bears a guanine base at position -1 (G-1), and it serves as a major recognition element for histidyl-tRNA synthetase (HisRS). Despite strong interests in the histidylation mechanism, the tRNA recognition and aminoacylation details are not fully understood. We herein present the 2.55 A crystal structure of HisRS complexed with tRNA(His), which reveals that G-1 recognition is principally nonspecific interactions on this base and is made possible by an enlarged binding pocket consisting of conserved glycines. The anticodon triplet makes additional specific contacts with the enzyme but the rest of the loop is flexible. Based on the crystallographic and biochemical studies, we inferred that the uniqueness of histidylation system originates from the enlarged binding pocket (for the extra base G-1) on HisRS absent in other aaRSs, and this structural complementarity between the 5' extremity of tRNA and enzyme is probably a result of coevolution of both.

Structural basis for recognition of G-1-containing tRNA by histidyl-tRNA synthetase.,Tian Q, Wang C, Liu Y, Xie W Nucleic Acids Res. 2015 Mar 11;43(5):2980-90. doi: 10.1093/nar/gkv129. Epub 2015 , Feb 26. PMID:25722375<ref>PMID:25722375</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4rdx" style="background-color:#fffaf0;"></div>

==See Also==
*[[TRNA|TRNA]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Histidine--tRNA ligase]]
[[Category: Tian, Q]]
[[Category: Wang, C]]
[[Category: Xie, W]]
[[Category: Aminoacyl-trna synthetase]]
[[Category: Aminoacylation]]
[[Category: Classii aar]]
[[Category: Histidine]]
[[Category: Ligase-rna complex]]
[[Category: Trna]]