View source for 4zkd


==Crystal structure of the S. cerevisiae Ski7 GTPase-like domain, bound to GDP and inorganic phosphate.==
<StructureSection load='4zkd' size='340' side='right'caption='[[4zkd]], [[Resolution|resolution]] 2.18&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4zkd]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ZKD OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4ZKD 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]] 2.181&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GDP:GUANOSINE-5-DIPHOSPHATE'>GDP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=4zkd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4zkd OCA], [https://pdbe.org/4zkd PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4zkd RCSB], [https://www.ebi.ac.uk/pdbsum/4zkd PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4zkd ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SKI7_YEAST SKI7_YEAST] Represses the expression of non-poly(A) mRNAs like L-A or M viruses and is therefore involved in antiviral system. Mediates interactions via its N-terminus between the exosome and the SKI complex which operate in the 3'-to-5' mRNA-decay pathway. By interacting with NAM7, is also required for nonsense-mediated 3'-to-5' mRNA-decay (NMD). May recognize a stalled 80S ribosome at the 3'-end of a nonstop mRNA which leads to the recruitment of the exosome and SKI complexes to the mRNAs to be degraded.<ref>PMID:10074137</ref> <ref>PMID:11027292</ref> <ref>PMID:11514438</ref> <ref>PMID:11532933</ref> <ref>PMID:11910110</ref> <ref>PMID:12769863</ref> <ref>PMID:12881429</ref> <ref>PMID:14671320</ref> <ref>PMID:15933721</ref> <ref>PMID:6371496</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Ski7 is a cofactor of the cytoplasmic exosome in budding yeast, functioning in both mRNA turnover and non-stop decay (NSD), a surveillance pathway that degrades faulty mRNAs lacking a stop codon. The C-terminal region of Ski7 (Ski7C) shares overall sequence similarity with the translational GTPase (trGTPase) Hbs1, but whether Ski7 has retained the properties of a trGTPase is unclear. Here, we report the high-resolution structures of Ski7C bound to either intact guanosine triphosphate (GTP) or guanosine diphosphate-Pi. The individual domains of Ski7C adopt the conformation characteristic of active trGTPases. Furthermore, the nucleotide-binding site of Ski7C shares similar features compared with active trGTPases, notably the presence of a characteristic monovalent cation. However, a suboptimal polar residue at the putative catalytic site and an unusual polar residue that interacts with the gamma-phosphate of GTP distinguish Ski7 from other trGTPases, suggesting it might function rather as a GTP-binding protein than as a GTP-hydrolyzing enzyme.

Saccharomyces cerevisiae Ski7 Is a GTP-Binding Protein Adopting the Characteristic Conformation of Active Translational GTPases.,Kowalinski E, Schuller A, Green R, Conti E Structure. 2015 May 28. pii: S0969-2126(15)00177-X. doi:, 10.1016/j.str.2015.04.018. PMID:26051716<ref>PMID:26051716</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4zkd" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae]]
[[Category: Conti E]]
[[Category: Kowalinski E]]