View source for 9fs6


==Cryo-EM structure of Saccharolobus solfataricus 30S initiation complex bound to Ss-aIF2beta leaderless mRNA with h44 in up position==
<StructureSection load='9fs6' size='340' side='right'caption='[[9fs6]], [[Resolution|resolution]] 2.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9fs6]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharolobus_solfataricus_P2 Saccharolobus solfataricus P2]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9FS6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9FS6 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 2.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=4AC:N(4)-ACETYLCYTIDINE-5-MONOPHOSPHATE'>4AC</scene>, <scene name='pdbligand=4SU:4-THIOURIDINE-5-MONOPHOSPHATE'>4SU</scene>, <scene name='pdbligand=5MC:5-METHYLCYTIDINE-5-MONOPHOSPHATE'>5MC</scene>, <scene name='pdbligand=5MU:5-METHYLURIDINE+5-MONOPHOSPHATE'>5MU</scene>, <scene name='pdbligand=6MZ:N6-METHYLADENOSINE-5-MONOPHOSPHATE'>6MZ</scene>, <scene name='pdbligand=A2M:2-O-METHYLADENOSINE+5-(DIHYDROGEN+PHOSPHATE)'>A2M</scene>, <scene name='pdbligand=C4J:(2~{S})-2-azanyl-4-[5-[(2~{S},3~{R},4~{S},5~{S})-3,4-bis(oxidanyl)-5-(phosphonooxymethyl)oxolan-2-yl]-3-methyl-2,6-bis(oxidanylidene)pyrimidin-1-yl]butanoic+acid'>C4J</scene>, <scene name='pdbligand=GTP:GUANOSINE-5-TRIPHOSPHATE'>GTP</scene>, <scene name='pdbligand=H2U:5,6-DIHYDROURIDINE-5-MONOPHOSPHATE'>H2U</scene>, <scene name='pdbligand=MA6:6N-DIMETHYLADENOSINE-5-MONOPHOSHATE'>MA6</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=OMC:O2-METHYLYCYTIDINE-5-MONOPHOSPHATE'>OMC</scene>, <scene name='pdbligand=OMG:O2-METHYLGUANOSINE-5-MONOPHOSPHATE'>OMG</scene>, <scene name='pdbligand=OMU:O2-METHYLURIDINE+5-MONOPHOSPHATE'>OMU</scene>, <scene name='pdbligand=PSU:PSEUDOURIDINE-5-MONOPHOSPHATE'>PSU</scene>, <scene name='pdbligand=SPM:SPERMINE'>SPM</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=9fs6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9fs6 OCA], [https://pdbe.org/9fs6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9fs6 RCSB], [https://www.ebi.ac.uk/pdbsum/9fs6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9fs6 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RS4_SACS2 RS4_SACS2] One of the primary rRNA binding proteins, it binds directly to 16S rRNA where it nucleates assembly of the body of the 30S subunit.[HAMAP-Rule:MF_01306]  With S5 and S12 plays an important role in translational accuracy.[HAMAP-Rule:MF_01306]
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== Publication Abstract from PubMed ==
The archaeal ribosome is of the eukaryotic type. TACK and Asgard superphyla, the closest relatives of eukaryotes, have ribosomes containing eukaryotic ribosomal proteins not found in other archaea, eS25, eS26 and eS30. Here, we investigate the case of Saccharolobus solfataricus, a TACK crenarchaeon, using mainly leaderless mRNAs. We characterize the small ribosomal subunit of S. solfataricus bound to SD-leadered or leaderless mRNAs. Cryo-EM structures show eS25, eS26 and eS30 bound to the small subunit. We identify two ribosomal proteins, aS33 and aS34, and an additional domain of eS6. Leaderless mRNAs are bound to the small subunit with contribution of their 5'-triphosphate group. Archaeal eS26 binds to the mRNA exit channel wrapped around the 3' end of rRNA, as in eukaryotes. Its position is not compatible with an SD:antiSD duplex. Our results suggest a positive role of eS26 in leaderless mRNAs translation and possible evolutionary routes from archaeal to eukaryotic translation.

Structures of Saccharolobus solfataricus initiation complexes with leaderless mRNAs highlight archaeal features and eukaryotic proximity.,Bourgeois G, Coureux PD, Lazennec-Schurdevin C, Madru C, Gaillard T, Duchateau M, Chamot-Rooke J, Bourcier S, Mechulam Y, Schmitt E Nat Commun. 2025 Jan 2;16(1):348. doi: 10.1038/s41467-024-55718-5. PMID:39753558<ref>PMID:39753558</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9fs6" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharolobus solfataricus P2]]
[[Category: Bourgeois G]]
[[Category: Coureux PD]]
[[Category: Mechulam Y]]
[[Category: Schmitt E]]