View source for 9ru9


==RPS26dC HEK mutant 80S ribosome bound to Kozak mRNA (RPS26dC-Kozak)==
<StructureSection load='9ru9' size='340' side='right'caption='[[9ru9]], [[Resolution|resolution]] 2.97&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ru9]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9RU9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9RU9 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]] 2.97&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1MA:6-HYDRO-1-METHYLADENOSINE-5-MONOPHOSPHATE'>1MA</scene>, <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=6MZ:N6-METHYLADENOSINE-5-MONOPHOSPHATE'>6MZ</scene>, <scene name='pdbligand=A2M:2-O-METHYLADENOSINE+5-(DIHYDROGEN+PHOSPHATE)'>A2M</scene>, <scene name='pdbligand=AME:N-ACETYLMETHIONINE'>AME</scene>, <scene name='pdbligand=ANM:ANISOMYCIN'>ANM</scene>, <scene name='pdbligand=B8N:(2~{R})-2-azanyl-4-[5-[(2~{S},3~{R},4~{S},5~{R})-3,4-bis(oxidanyl)-5-(phosphonooxymethyl)oxolan-2-yl]-3-methyl-2,6-bis(oxidanylidene)pyrimidin-1-yl]butanoic+acid'>B8N</scene>, <scene name='pdbligand=G7M:N7-METHYL-GUANOSINE-5-MONOPHOSPHATE'>G7M</scene>, <scene name='pdbligand=H2U:5,6-DIHYDROURIDINE-5-MONOPHOSPHATE'>H2U</scene>, <scene name='pdbligand=HIC:4-METHYL-HISTIDINE'>HIC</scene>, <scene name='pdbligand=HY3:3-HYDROXYPROLINE'>HY3</scene>, <scene name='pdbligand=HYG:HYGROMYCIN+B'>HYG</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=M3L:N-TRIMETHYLLYSINE'>M3L</scene>, <scene name='pdbligand=MA6:6N-DIMETHYLADENOSINE-5-MONOPHOSHATE'>MA6</scene>, <scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=MLZ:N-METHYL-LYSINE'>MLZ</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=SAC:N-ACETYL-SERINE'>SAC</scene>, <scene name='pdbligand=UR3:3-METHYLURIDINE-5-MONOPHOSHATE'>UR3</scene>, <scene name='pdbligand=UY1:[(2~{R},3~{R},4~{R},5~{S})-5-[2,4-bis(oxidanylidene)-1~{H}-pyrimidin-5-yl]-4-methoxy-3-oxidanyl-oxolan-2-yl]methyl+dihydrogen+phosphate'>UY1</scene>, <scene name='pdbligand=V5N:(2~{S},3~{S})-2-azanyl-3-(1~{H}-imidazol-5-yl)-3-oxidanyl-propanoic+acid'>V5N</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=9ru9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ru9 OCA], [https://pdbe.org/9ru9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ru9 RCSB], [https://www.ebi.ac.uk/pdbsum/9ru9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ru9 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RL22_HUMAN RL22_HUMAN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The ribosome mRNA channel is central to translation, yet its role in regulatory mechanisms remains unclear. Using cryo-EM of human ribosomal complexes bound to Kozak and TISU mRNAs from wild-type (WT) and RPS26/eS26 mutant (RPS26dC) cells, we demonstrate that both RPS26/eS26 and mRNA adopt distinct conformations, explaining the opposing effects of RPS26dC on their activity. Translatome studies of WT and RPS26dC reveal AUG-context-dependent changes in 48S and 80S initiation complexes and slower scanning. Downregulated mRNAs are enriched for specific AUG-upstream nucleotides and a -1-cytosine contacting 18S rRNA G1207, an interaction lost in RPS26dC. Strongly affected transcripts include replication-dependent histones, which, despite short 5'UTRs and suboptimal Kozak, exhibit robust translation activity that is RPS26/eS26-dependent. We identify a translational enhancer in the H2B 5'UTR (-16 to -9) overlapping predicted RPS26/eS26-binding sites, with a distinct ribosome-bound conformation. Exploiting these features, we engineered a high-efficiency translational cassette with minimal leaky scanning. These findings underscore the role of the ribosome's mRNA channel in selective translation and its therapeutic potential.

Structural and molecular basis of specialized translation mediated by the ribosome mRNA-binding channel.,Fraticelli D, Hiregange DG, Weiss B, Ogran A, Havkin-Solomon T, Roman IM, Bashan A, Yonath A, Dikstein R Nat Commun. 2026 Apr 29. doi: 10.1038/s41467-026-72263-5. PMID:42056121<ref>PMID:42056121</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9ru9" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Bashan A]]
[[Category: Dikstein R]]
[[Category: Fraticelli D]]
[[Category: Hiregange DG]]
[[Category: Yonath A]]