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-Structure paper
Title | Mechanism of membrane-tethered mitochondrial protein synthesis. |
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Journal, issue, pages | Science, Vol. 371, Issue 6531, Page 846-849, Year 2021 |
Publish date | Feb 19, 2021 |
Authors | Yuzuru Itoh / Juni Andréll / Austin Choi / Uwe Richter / Priyanka Maiti / Robert B Best / Antoni Barrientos / Brendan J Battersby / Alexey Amunts / |
PubMed Abstract | Mitochondrial ribosomes (mitoribosomes) are tethered to the mitochondrial inner membrane to facilitate the cotranslational membrane insertion of the synthesized proteins. We report cryo-electron ...Mitochondrial ribosomes (mitoribosomes) are tethered to the mitochondrial inner membrane to facilitate the cotranslational membrane insertion of the synthesized proteins. We report cryo-electron microscopy structures of human mitoribosomes with nascent polypeptide, bound to the insertase oxidase assembly 1-like (OXA1L) through three distinct contact sites. OXA1L binding is correlated with a series of conformational changes in the mitoribosomal large subunit that catalyze the delivery of newly synthesized polypeptides. The mechanism relies on the folding of mL45 inside the exit tunnel, forming two specific constriction sites that would limit helix formation of the nascent chain. A gap is formed between the exit and the membrane, making the newly synthesized proteins accessible. Our data elucidate the basis by which mitoribosomes interact with the OXA1L insertase to couple protein synthesis and membrane delivery. |
External links | Science / PubMed:33602856 / PubMed Central |
Methods | EM (single particle) |
Resolution | 2.59 - 3.2 Å |
Structure data | EMDB-11278, PDB-6zm5: EMDB-11279, PDB-6zm6: EMDB-11280: EMDB-11281: EMDB-11282: EMDB-11283: EMDB-11284: EMDB-11285: EMDB-11286: EMDB-11287: |
Chemicals | ChemComp-MG: ChemComp-K: ChemComp-ZN: ChemComp-FES: ChemComp-ATP: ChemComp-GTP: ChemComp-ALA: ChemComp-HOH: |
Source |
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Keywords | RIBOSOME / mitochondrion / translation / membrane insertion / translocon / peptidyl-tRNA / closed nascent-polypeptide tunnel |