View source for 3jbv


==Mechanisms of Ribosome Stalling by SecM at Multiple Elongation Steps==
<SX load='3jbv' size='340' side='right' viewer='molstar' caption='[[3jbv]], [[Resolution|resolution]] 3.32&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3jbv]] 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=3JBV OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3JBV 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]] 3.32&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CLM:CHLORAMPHENICOL'>CLM</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=3jbv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3jbv OCA], [https://pdbe.org/3jbv PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3jbv RCSB], [https://www.ebi.ac.uk/pdbsum/3jbv PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3jbv ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RS3_ECOLI RS3_ECOLI] Binds the lower part of the 30S subunit head. Binds mRNA in the 70S ribosome, positioning it for translation (By similarity).<ref>PMID:15652481</ref>   Plays a role in mRNA unwinding by the ribosome, possibly by forming part of a processivity clamp.<ref>PMID:15652481</ref> 
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== Publication Abstract from PubMed ==
Regulation of translating ribosomes is a major component of gene expression control network. In Escherichia coli, ribosome stalling by the C-terminal arrest sequence of SecM regulates the SecA-dependent secretion pathway. Previous studies reported many residues of SecM peptide and ribosome exit tunnel are critical for stalling. However, the underlying molecular mechanism is still not clear at the atomic level. Here, we present two cryo-EM structures of the SecM-stalled ribosomes at 3.3-3.7 A resolution, which reveal two different stalling mechanisms at distinct elongation steps of the translation cycle: one is due to the inactivation of ribosomal peptidyl-transferase center which inhibits peptide bond formation with the incoming prolyl-tRNA; the other is the prolonged residence of the peptidyl-RNA at the hybrid A/P site which inhibits the full-scale tRNA translocation. These results demonstrate an elegant control of translation cycle by regulatory peptides through a continuous, dynamic reshaping of the functional center of the ribosome.

Mechanisms of ribosome stalling by SecM at multiple elongation steps.,Zhang J, Pan X, Yan K, Sun S, Gao N, Sui SF Elife. 2015 Dec 14;4. pii: e09684. doi: 10.7554/eLife.09684. PMID:26670735<ref>PMID:26670735</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3jbv" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribosome 3D structures|Ribosome 3D structures]]
== References ==
<references/>
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[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Gao N]]
[[Category: Pan XJ]]
[[Category: Sui SF]]
[[Category: Sun S]]
[[Category: Yan KG]]
[[Category: Zhang J]]