6VLZ

Structure of the human mitochondrial ribosome-EF-G1 complex (ClassI)

This is a non-PDB format compatible entry.

Summary for 6VLZ

• Entry DOI: 10.2210/pdb6vlz/pdb
• EMDB information: 21233
• Descriptor: 12s rRNA, 28S ribosomal protein S18b, mitochondrial, 28S ribosomal protein S18c, mitochondrial, ... (92 entities in total)
• Functional Keywords: mitochondrial elongation factor-g1, 55s ribosome, ribosome
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 90
• Total formula weight: 3057182.32

Authors

Sharma, M.R.,Koripella, R.K.,Agrawal, R.K. (deposition date: 2020-01-27, release date: 2020-08-05, Last modification date: 2024-03-06)

Primary citation

Koripella, R.K.,Sharma, M.R.,Bhargava, K.,Datta, P.P.,Kaushal, P.S.,Keshavan, P.,Spremulli, L.L.,Banavali, N.K.,Agrawal, R.K.
Structures of the human mitochondrial ribosome bound to EF-G1 reveal distinct features of mitochondrial translation elongation.
Nat Commun, 11:3830-3830, 2020

PubMed Abstract: The mammalian mitochondrial ribosome (mitoribosome) and its associated translational factors have evolved to accommodate greater participation of proteins in mitochondrial translation. Here we present the 2.68-3.96 Å cryo-EM structures of the human 55S mitoribosome in complex with the human mitochondrial elongation factor G1 (EF-G1) in three distinct conformational states, including an intermediate state and a post-translocational state. These structures reveal the role of several mitochondria-specific (mito-specific) mitoribosomal proteins (MRPs) and a mito-specific segment of EF-G1 in mitochondrial tRNA (tRNA) translocation. In particular, the mito-specific C-terminal extension in EF-G1 is directly involved in translocation of the acceptor arm of the A-site tRNA. In addition to the ratchet-like and independent head-swiveling motions exhibited by the small mitoribosomal subunit, we discover significant conformational changes in MRP mL45 at the nascent polypeptide-exit site within the large mitoribosomal subunit that could be critical for tethering of the elongating mitoribosome onto the inner-mitochondrial membrane.

PubMed: 32737313
DOI: 10.1038/s41467-020-17715-2

Experimental method

ELECTRON MICROSCOPY (2.97 Å)