This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

4cg6

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 14:57, 11 August 2016

Cryo-em of the Sec61-complex bound to the 80s ribosome translating a membrane-inserting substrate

Structural highlights

4cg6 is a 4 chain structure with sequence from Canfa. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	4cg5, 4cg7
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Publication Abstract from PubMed

The biogenesis of secretory as well as transmembrane proteins requires the activity of the universally conserved protein-conducting channel (PCC), the Sec61 complex (SecY complex in bacteria). In eukaryotic cells the PCC is located in the membrane of the endoplasmic reticulum where it can bind to translating ribosomes for co-translational protein transport. The Sec complex consists of three subunits (Sec61alpha, beta and gamma) and provides an aqueous environment for the translocation of hydrophilic peptides as well as a lateral opening in the Sec61alpha subunit that has been proposed to act as a gate for the membrane partitioning of hydrophobic domains. A plug helix and a so-called pore ring are believed to seal the PCC against ion flow and are proposed to rearrange for accommodation of translocating peptides. Several crystal and cryo-electron microscopy structures revealed different conformations of closed and partially open Sec61 and SecY complexes. However, in none of these samples has the translocation state been unambiguously defined biochemically. Here we present cryo-electron microscopy structures of ribosome-bound Sec61 complexes engaged in translocation or membrane insertion of nascent peptides. Our data show that a hydrophilic peptide can translocate through the Sec complex with an essentially closed lateral gate and an only slightly rearranged central channel. Membrane insertion of a hydrophobic domain seems to occur with the Sec complex opening the proposed lateral gate while rearranging the plug to maintain an ion permeability barrier. Taken together, we provide a structural model for the basic activities of the Sec61 complex as a protein-conducting channel.

Structures of the Sec61 complex engaged in nascent peptide translocation or membrane insertion.,Gogala M, Becker T, Beatrix B, Armache JP, Barrio-Garcia C, Berninghausen O, Beckmann R Nature. 2014 Feb 6;506(7486):107-10. doi: 10.1038/nature12950. PMID:24499919^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Gogala M, Becker T, Beatrix B, Armache JP, Barrio-Garcia C, Berninghausen O, Beckmann R. Structures of the Sec61 complex engaged in nascent peptide translocation or membrane insertion. Nature. 2014 Feb 6;506(7486):107-10. doi: 10.1038/nature12950. PMID:24499919 doi:http://dx.doi.org/10.1038/nature12950

1 Structural highlights
2 Publication Abstract from PubMed
3 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4cg6"

@@ Line 1: / Line 1: @@
 ==Cryo-em of the Sec61-complex bound to the 80s ribosome translating a membrane-inserting substrate==
 <StructureSection load='4cg6' size='340' side='right' caption='[[4cg6]], [[Resolution|resolution]] 7.80&Aring;' scene=''>
@@ Line 4: / Line 5: @@
 <table><tr><td colspan='2'>[[4cg6]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Canfa Canfa]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4CG6 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4CG6 FirstGlance]. <br>
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4cg5|4cg5]], [[4cg7|4cg7]]</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4cg6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4cg6 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4cg6 RCSB], [http://www.ebi.ac.uk/pdbsum/4cg6 PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4cg6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4cg6 OCA], [http://pdbe.org/4cg6 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4cg6 RCSB], [http://www.ebi.ac.uk/pdbsum/4cg6 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4cg6 ProSAT]</span></td></tr>
 </table>
 <div style="background-color:#fffaf0;">
@@ Line 14: / Line 15: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 4cg6" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

4cg6

From Proteopedia

Revision as of 14:57, 11 August 2016

Cryo-em of the Sec61-complex bound to the 80s ribosome translating a membrane-inserting substrate

Structural highlights

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox