5GAG

RNC in complex with SRP-SR in the closed state

Summary for 5GAG

• Entry DOI: 10.2210/pdb5gag/pdb
• EMDB information: 8003
• Descriptor: SRP 4.5S RNA, 50S ribosomal protein L9, 50S ribosomal protein L10, ... (38 entities in total)
• Functional Keywords: ribosome nascent chain, srp, sr, ribosome
• Biological source: Escherichia coli; More
• Total number of polymer chains: 36
• Total formula weight: 1472712.22

Authors

Jomaa, A.,Boehringer, D.,Leibundgut, M.,Ban, N. (deposition date: 2015-11-26, release date: 2016-01-27, Last modification date: 2024-05-15)

Primary citation

Jomaa, A.,Boehringer, D.,Leibundgut, M.,Ban, N.
Structures of the E. coli translating ribosome with SRP and its receptor and with the translocon.
Nat Commun, 7:10471-10471, 2016

PubMed Abstract: Co-translational protein targeting to membranes is a universally conserved process. Central steps include cargo recognition by the signal recognition particle and handover to the Sec translocon. Here we present snapshots of key co-translational-targeting complexes solved by cryo-electron microscopy at near-atomic resolution, establishing the molecular contacts between the Escherichia coli translating ribosome, the signal recognition particle and the translocon. Our results reveal the conformational changes that regulate the latching of the signal sequence, the release of the heterodimeric domains of the signal recognition particle and its receptor, and the handover of the signal sequence to the translocon. We also observe that the signal recognition particle and the translocon insert-specific structural elements into the ribosomal tunnel to remodel it, possibly to sense nascent chains. Our work provides structural evidence for a conformational state of the signal recognition particle and its receptor primed for translocon binding to the ribosome-nascent chain complex.

PubMed: 26804923
DOI: 10.1038/ncomms10471

Experimental method

ELECTRON MICROSCOPY (3.8 Å)