4D5Y

Cryo-EM structures of ribosomal 80S complexes with termination factors and cricket paralysis virus IRES reveal the IRES in the translocated state

This is a non-PDB format compatible entry.

Summary for 4D5Y

• Entry DOI: 10.2210/pdb4d5y/pdb
• Related: 4D5L 4D5N 4D61 4D67
• EMDB information: 2810
• Descriptor: 60S RIBOSOMAL PROTEIN UL2, 60S RIBOSOMAL PROTEIN UL5, 60S RIBOSOMAL PROTEIN EL13, ... (46 entities in total)
• Functional Keywords: crpv ires, ribosome, termination, release factors
• Biological source: ORYCTOLAGUS CUNICULUS (RABBIT); More
• Total number of polymer chains: 46
• Total formula weight: 2578728.21

Authors

Muhs, M.,Hilal, T.,Mielke, T.,Skabkin, M.A.,Sanbonmatsu, K.Y.,Pestova, T.V.,Spahn, C.M.T. (deposition date: 2014-11-07, release date: 2015-03-04, Last modification date: 2024-10-09)

Primary citation

Muhs, M.,Hilal, T.,Mielke, T.,Skabkin, M.A.,Sanbonmatsu, K.Y.,Pestova, T.V.,Spahn, C.M.T.
Cryo-Em Structures of Ribosomal 80S Complexes with Termination Factors and Cricket Paralysis Virus Ires Reveal the Ires in the Translocated State
Mol.Cell, 57:422-, 2015

PubMed Abstract: The cricket paralysis virus (CrPV) uses an internal ribosomal entry site (IRES) to hijack the ribosome. In a remarkable RNA-based mechanism involving neither initiation factor nor initiator tRNA, the CrPV IRES jumpstarts translation in the elongation phase from the ribosomal A site. Here, we present cryoelectron microscopy (cryo-EM) maps of 80S⋅CrPV-STOP ⋅ eRF1 ⋅ eRF3 ⋅ GMPPNP and 80S⋅CrPV-STOP ⋅ eRF1 complexes, revealing a previously unseen binding state of the IRES and directly rationalizing that an eEF2-dependent translocation of the IRES is required to allow the first A-site occupation. During this unusual translocation event, the IRES undergoes a pronounced conformational change to a more stretched conformation. At the same time, our structural analysis provides information about the binding modes of eRF1 ⋅ eRF3 ⋅ GMPPNP and eRF1 in a minimal system. It shows that neither eRF3 nor ABCE1 are required for the active conformation of eRF1 at the intersection between eukaryotic termination and recycling.

PubMed: 25601755
DOI: 10.1016/J.MOLCEL.2014.12.016

Experimental method

ELECTRON MICROSCOPY (9 Å)