7A5F

Structure of the stalled human mitoribosome with P- and E-site mt-tRNAs

This is a non-PDB format compatible entry.

Summary for 7A5F

• Entry DOI: 10.2210/pdb7a5f/pdb
• EMDB information: 11641
• Descriptor: nascent chain, 39S ribosomal protein L13, mitochondrial, 39S ribosomal protein L14, mitochondrial, ... (96 entities in total)
• Functional Keywords: mitochondrial ribosome, ribosome stalling, cryo-em, ribosome
• Biological source: Homo sapiens; More
• Total number of polymer chains: 91
• Total formula weight: 3050774.70

Authors

Desai, N.,Yang, H.,Chandrasekaran, V.,Kazi, R.,Minczuk, M.,Ramakrishnan, V. (deposition date: 2020-08-21, release date: 2020-12-23, Last modification date: 2024-10-23)

Primary citation

Desai, N.,Yang, H.,Chandrasekaran, V.,Kazi, R.,Minczuk, M.,Ramakrishnan, V.
Elongational stalling activates mitoribosome-associated quality control.
Science, 370:1105-1110, 2020

PubMed 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.

PubMed: 33243891
DOI: 10.1126/science.abc7782

Experimental method

ELECTRON MICROSCOPY (4.4 Å)