View source for 6gyv


==Lariat-capping ribozyme (circular permutation form)==
<StructureSection load='6gyv' size='340' side='right'caption='[[6gyv]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6gyv]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Didymium_iridis Didymium iridis]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=4p95 4p95]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6GYV OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6GYV FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.5000362&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MES:2-(N-MORPHOLINO)-ETHANESULFONIC+ACID'>MES</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=6gyv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6gyv OCA], [https://pdbe.org/6gyv PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6gyv RCSB], [https://www.ebi.ac.uk/pdbsum/6gyv PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6gyv ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The lariat-capping (LC) ribozyme is a natural ribozyme isolated from eukaryotic microorganisms. Despite apparent structural similarity to group I introns, the LC ribozyme catalyzes cleavage by a 2',5' branching reaction, leaving the 3' product with a 3-nt lariat cap that functionally substitutes for a conventional mRNA cap in the downstream pre-mRNA encoding a homing endonuclease. We describe the crystal structures of the precleavage and postcleavage LC ribozymes, which suggest that structural features inherited from group I ribozymes have undergone speciation due to profound changes in molecular selection pressure, ultimately giving rise to an original branching ribozyme family. The structures elucidate the role of key elements that regulate the activity of the LC ribozyme by conformational switching and suggest a mechanism by which the signal for branching is transmitted to the catalytic core. The structures also show how conserved interactions twist residues, forming the lariat to join chemical groups involved in branching.

Speciation of a group I intron into a lariat capping ribozyme.,Meyer M, Nielsen H, Olieric V, Roblin P, Johansen SD, Westhof E, Masquida B Proc Natl Acad Sci U S A. 2014 May 12. PMID:24821772<ref>PMID:24821772</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6gyv" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribozyme 3D structures|Ribozyme 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Didymium iridis]]
[[Category: Large Structures]]
[[Category: Johansen SD]]
[[Category: Masquida B]]
[[Category: Meyer M]]
[[Category: Nielsen H]]
[[Category: Olieric V]]
[[Category: Roblin P]]
[[Category: Westhof E]]