2WWB

CRYO-EM STRUCTURE OF THE MAMMALIAN SEC61 COMPLEX BOUND TO THE ACTIVELY TRANSLATING WHEAT GERM 80S RIBOSOME

Summary for 2WWB

• Entry DOI: 10.2210/pdb2wwb/pdb
• Related: 1K5Y 1S1I 2WWA 2WWB
• EMDB information: 1651 1652 1667 1668 1669
• Descriptor: PROTEIN TRANSPORT PROTEIN SEC61 SUBUNIT ALPHA ISOFORM 1, 60S RIBOSOMAL PROTEIN L19, 60S RIBOSOMAL PROTEIN L25, ... (15 entities in total)
• Functional Keywords: ribosome, protein exit tunnel, cotranslational protein translocation, protein conducting channel, signal sequence
• Biological source: CANIS LUPUS FAMILIARIS (DOG); More
• Total number of polymer chains: 15
• Total formula weight: 258757.37

Authors

Becker, T.,Mandon, E.,Bhushan, S.,Jarasch, A.,Armache, J.P.,Funes, S.,Jossinet, F.,Gumbart, J.,Mielke, T.,Berninghausen, O.,Schulten, K.,Westhof, E.,Gilmore, R.,Beckmann, R. (deposition date: 2009-10-22, release date: 2009-12-08, Last modification date: 2024-05-08)

Primary citation

Becker, T.,Bhushan, S.,Jarasch, A.,Armache, J.P.,Funes, S.,Jossinet, F.,Gumbart, J.,Mielke, T.,Berninghausen, O.,Schulten, K.,Westhof, E.,Gilmore, R.,Mandon, E.,Beckmann, R.
Structure of Monomeric Yeast and Mammalian Sec61 Complexes Interacting with the Translating Ribosome.
Science, 326:1369-, 2009

PubMed Abstract: The trimeric Sec61/SecY complex is a protein-conducting channel (PCC) for secretory and membrane proteins. Although Sec complexes can form oligomers, it has been suggested that a single copy may serve as an active PCC. We determined subnanometer-resolution cryo-electron microscopy structures of eukaryotic ribosome-Sec61 complexes. In combination with biochemical data, we found that in both idle and active states, the Sec complex is not oligomeric and interacts mainly via two cytoplasmic loops with the universal ribosomal adaptor site. In the active state, the ribosomal tunnel and a central pore of the monomeric PCC were occupied by the nascent chain, contacting loop 6 of the Sec complex. This provides a structural basis for the activity of a solitary Sec complex in cotranslational protein translocation.

PubMed: 19933108
DOI: 10.1126/SCIENCE.1178535

Experimental method

ELECTRON MICROSCOPY (6.48 Å)