View source for 7acr


==Structure of post-translocated trans-translation complex on E. coli stalled ribosome.==
<StructureSection load='7acr' size='340' side='right'caption='[[7acr]], [[Resolution|resolution]] 3.44&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7acr]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7ACR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7ACR 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]] 3.44&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=0TD:(3S)-3-(METHYLSULFANYL)-L-ASPARTIC+ACID'>0TD</scene>, <scene name='pdbligand=1MG:1N-METHYLGUANOSINE-5-MONOPHOSPHATE'>1MG</scene>, <scene name='pdbligand=2MA:2-METHYLADENOSINE-5-MONOPHOSPHATE'>2MA</scene>, <scene name='pdbligand=2MG:2N-METHYLGUANOSINE-5-MONOPHOSPHATE'>2MG</scene>, <scene name='pdbligand=3TD:(1S)-1,4-ANHYDRO-1-(3-METHYL-2,4-DIOXO-1,2,3,4-TETRAHYDROPYRIMIDIN-5-YL)-5-O-PHOSPHONO-D-RIBITOL'>3TD</scene>, <scene name='pdbligand=4D4:(2S,3R)-2-AZANYL-5-CARBAMIMIDAMIDO-3-OXIDANYL-PENTANOIC+ACID'>4D4</scene>, <scene name='pdbligand=4OC:4N,O2-METHYLCYTIDINE-5-MONOPHOSPHATE'>4OC</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=G7M:N7-METHYL-GUANOSINE-5-MONOPHOSPHATE'>G7M</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=UR3:3-METHYLURIDINE-5-MONOPHOSHATE'>UR3</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=7acr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7acr OCA], [https://pdbe.org/7acr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7acr RCSB], [https://www.ebi.ac.uk/pdbsum/7acr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7acr ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RL36_ECOLI RL36_ECOLI] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
In bacteria, trans-translation is the main rescue system, freeing ribosomes stalled on defective messenger RNAs. This mechanism is driven by small protein B (SmpB) and transfer-messenger RNA (tmRNA), a hybrid RNA known to have both a tRNA-like and an mRNA-like domain. Here we present four cryo-EM structures of the ribosome during trans-translation at resolutions from 3.0 to 3.4 A. These include the high-resolution structure of the whole pre-accommodated state, as well as structures of the accommodated state, the translocated state, and a translocation intermediate. Together, they shed light on the movements of the tmRNA-SmpB complex in the ribosome, from its delivery by the elongation factor EF-Tu to its passage through the ribosomal A and P sites after the opening of the B1 bridges. Additionally, we describe the interactions between the tmRNA-SmpB complex and the ribosome. These explain why the process does not interfere with canonical translation.

Structures of tmRNA and SmpB as they transit through the ribosome.,Guyomar C, D'Urso G, Chat S, Giudice E, Gillet R Nat Commun. 2021 Aug 13;12(1):4909. doi: 10.1038/s41467-021-24881-4. PMID:34389707<ref>PMID:34389707</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7acr" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribosome 3D structures|Ribosome 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Chat S]]
[[Category: D'Urso G]]
[[Category: Gillet R]]
[[Category: Giudice E]]
[[Category: Guyomar C]]