EMD-8003

Single-particle
3.8 Å
EMD-8003 Deposition: 11/12/2015
Map released: 27/01/2016
Last modified: 15/05/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-8003

RNC in complex with SRP-SR in the closed state

EMD-8003

Single-particle
3.8 Å
EMD-8003 Deposition: 11/12/2015
Map released: 27/01/2016
Last modified: 15/05/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Escherichia coli, Escherichia coli (strain K12)
Sample: Ribosome nascent chain complex with SRP-SR in the closed state
Fitted models: 5gag (Avg. Q-score: 0.41)

Deposition Authors: Jomaa A , Boehringer D
Structures of the E. coli translating ribosome with SRP and its receptor and with the translocon.
Jomaa A , Boehringer D , Leibundgut M , Ban N
(2016) Nat Commun , 7 , 10471 - 10471
PUBMED: 26804923
DOI: doi:10.1038/ncomms10471
ISSN: 2041-1723
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.