7L08

Cryo-EM structure of the human 55S mitoribosome-RRFmt complex.

This is a non-PDB format compatible entry.

Summary for 7L08

• Entry DOI: 10.2210/pdb7l08/pdb
• EMDB information: 23096
• Descriptor: 12S rRNA, 28S ribosomal protein S18b, mitochondrial, 28S ribosomal protein S18c, mitochondrial, ... (89 entities in total)
• Functional Keywords: mtefg2 and mtrrf, ribosome
• Biological source: Homo sapiens; More
• Total number of polymer chains: 87
• Total formula weight: 2950296.38

Authors

Koripella, R.,Agrawal, E.K.,Deep, A.,Agrawal, R.K. (deposition date: 2020-12-11, release date: 2021-05-12, Last modification date: 2024-10-16)

Primary citation

Koripella, R.K.,Deep, A.,Agrawal, E.K.,Keshavan, P.,Banavali, N.K.,Agrawal, R.K.
Distinct mechanisms of the human mitoribosome recycling and antibiotic resistance.
Nat Commun, 12:3607-3607, 2021

PubMed 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 (RRF) and a recycling-specific homolog of elongation factor G (EF-G2). These structures clarify an unusual role of a mitochondria-specific segment of RRF, identify the structural distinctions that confer functional specificity to EF-G2, 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-G2 is markedly different from that of mitochondrial elongation factor EF-G1, suggesting that the two human EF-Gs have evolved diversely to negate the effect of a bacterial antibiotic.

PubMed: 34127662
DOI: 10.1038/s41467-021-23726-4

Experimental method

ELECTRON MICROSCOPY (3.49 Å)