EMD-11643

Single-particle
3.3 Å
EMD-11643 Deposition: 21/08/2020
Map released: 23/12/2020
Last modified: 01/03/2023
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-11643

Structure of the split human mitoribosomal large subunit with rescue factors mtRF-R and MTRES1

EMD-11643

Single-particle
3.3 Å
EMD-11643 Deposition: 21/08/2020
Map released: 23/12/2020
Last modified: 01/03/2023
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: human
Sample: human mitoribosome
Fitted models: 7a5h (Avg. Q-score: 0.553)

Deposition Authors: Desai N , Yang H , Chandrasekaran V , Kazi R , Minczuk M , Ramakrishnan V
Elongational stalling activates mitoribosome-associated quality control.
Desai N , Yang H , Chandrasekaran V , Kazi R , Minczuk M , Ramakrishnan V
(2020) Science , 370 , 1105 - 1110
PUBMED: 33243891
DOI: doi:10.1126/science.abc7782
ISSN: 1095-9203
ASTM: SCIEAS
Abstract:
The human mitochondrial ribosome (mitoribosome) and associated proteins regulate the synthesis of 13 essential subunits of the oxidative phosphorylation complexes. We report the discovery of a mitoribosome-associated quality control pathway that responds to interruptions during elongation, and we present structures at 3.1- to 3.3-angstrom resolution of mitoribosomal large subunits trapped during ribosome rescue. Release factor homolog C12orf65 (mtRF-R) and RNA binding protein C6orf203 (MTRES1) eject the nascent chain and peptidyl transfer RNA (tRNA), respectively, from stalled ribosomes. Recruitment of mitoribosome biogenesis factors to these quality control intermediates suggests additional roles for these factors during mitoribosome rescue. We also report related cryo-electron microscopy structures (3.7 to 4.4 angstrom resolution) of elongating mitoribosomes bound to tRNAs, nascent polypeptides, the guanosine triphosphatase elongation factors mtEF-Tu and mtEF-G1, and the Oxa1L translocase.