4crm
From Proteopedia
Cryo-EM of a pre-recycling complex with eRF1 and ABCE1
Structural highlights
FunctionRLI1_YEAST Component of the multifactor complex (MFC) involved in translation initiation. Required for the binding of MFC to the 40S ribosome. Required for the processing and nuclear export of the 60S and 40S ribosomal subunits.[1] [2] [3] Publication Abstract from PubMedTermination and ribosome recycling are essential processes in translation. In eukaryotes, a stop codon in the ribosomal A site is decoded by a ternary complex consisting of release factors eRF1 and guanosine triphosphate (GTP)-bound eRF3. After GTP hydrolysis, eRF3 dissociates, and ABCE1 can bind to eRF1-loaded ribosomes to stimulate peptide release and ribosomal subunit dissociation. Here, we present cryoelectron microscopic (cryo-EM) structures of a pretermination complex containing eRF1-eRF3 and a termination/prerecycling complex containing eRF1-ABCE1. eRF1 undergoes drastic conformational changes: its central domain harboring the catalytically important GGQ loop is either packed against eRF3 or swung toward the peptidyl transferase center when bound to ABCE1. Additionally, in complex with eRF3, the N-terminal domain of eRF1 positions the conserved NIKS motif proximal to the stop codon, supporting its suggested role in decoding, yet it appears to be delocalized in the presence of ABCE1. These results suggest that stop codon decoding and peptide release can be uncoupled during termination. Cryoelectron Microscopic Structures of Eukaryotic Translation Termination Complexes Containing eRF1-eRF3 or eRF1-ABCE1.,Preis A, Heuer A, Barrio-Garcia C, Hauser A, Eyler DE, Berninghausen O, Green R, Becker T, Beckmann R Cell Rep. 2014 Jul 10;8(1):59-65. doi: 10.1016/j.celrep.2014.04.058. Epub 2014, Jul 4. PMID:25001285[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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