EMD-23114

Single-particle
3.49 Å
EMD-23114 Deposition: 15/12/2020
Map released: 12/05/2021
Last modified: 01/12/2021
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-23114

Cryo-EM structure of the human 55S mitoribosome in complex with RRFmt and EF-G2mt

EMD-23114

Single-particle
3.49 Å
EMD-23114 Deposition: 15/12/2020
Map released: 12/05/2021
Last modified: 01/12/2021
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Homo sapiens
Sample: 55S Mitochondrial Ribosome, mtEFG2, mtRRF
Raw data: EMPIAR-10703

Deposition Authors: Agrawal E, Koripella R
Distinct mechanisms of the human mitoribosome recycling and antibiotic resistance.
Koripella RK , Deep A , Agrawal EK, Keshavan P , Banavali NK , Agrawal RK
(2021) Nat Commun , 12 , 3607 - 3607
PUBMED: 34127662
DOI: doi:10.1038/s41467-021-23726-4
ISSN: 2041-1723
Abstract:
Ribosomes are recycled for a new round of translation initiation by dissociation of ribosomal subunits, messenger RNA and transfer RNA from their translational post-termination complex. Here we present cryo-EM structures of the human 55S mitochondrial ribosome (mitoribosome) and the mitoribosomal large 39S subunit in complex with mitoribosome recycling factor (RRFmt) and a recycling-specific homolog of elongation factor G (EF-G2mt). These structures clarify an unusual role of a mitochondria-specific segment of RRFmt, identify the structural distinctions that confer functional specificity to EF-G2mt, and show that the deacylated tRNA remains with the dissociated 39S subunit, suggesting a distinct sequence of events in mitoribosome recycling. Furthermore, biochemical and structural analyses reveal that the molecular mechanism of antibiotic fusidic acid resistance for EF-G2mt is markedly different from that of mitochondrial elongation factor EF-G1mt, suggesting that the two human EF-Gmts have evolved diversely to negate the effect of a bacterial antibiotic.