3JBU

Mechanisms of Ribosome Stalling by SecM at Multiple Elongation Steps

This is a non-PDB format compatible entry.

Summary for 3JBU

• Entry DOI: 10.2210/pdb3jbu/pdb
• Related: 3JBV
• EMDB information: 6483
• Descriptor: 30S ribosomal protein S2, 30S ribosomal protein S11, 30S ribosomal protein S12, ... (54 entities in total)
• Functional Keywords: single particle analysis, ribosome stalling, ribosome
• Biological source: Escherichia coli K-12; More
• Total number of polymer chains: 54
• Total formula weight: 2166424.51

Authors

Zhang, J.,Pan, X.J.,Yan, K.G.,Sun, S.,Gao, N.,Sui, S.F. (deposition date: 2015-10-16, release date: 2016-01-27, Last modification date: 2024-03-20)

Primary citation

Zhang, J.,Pan, X.,Yan, K.,Sun, S.,Gao, N.,Sui, S.F.
Mechanisms of ribosome stalling by SecM at multiple elongation steps
Elife, 4:-, 2015

PubMed Abstract: 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 Å 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.

PubMed: 26670735
DOI: 10.7554/eLife.09684

Experimental method

ELECTRON MICROSCOPY (3.64 Å)