Mitoribosome structure with cofactors and modifications reveals mechanism of ligand binding and interactions with L1 stalk.
Singh, V., Itoh, Y., Del'Olio, S., Hassan, A., Naschberger, A., Flygaard, R.K., Nobe, Y., Izumikawa, K., Aibara, S., Andrell, J., Whitford, P.C., Barrientos, A., Taoka, M., Amunts, A.(2024) Nat Commun 15: 4272-4272
- PubMed: 38769321 
- DOI: https://doi.org/10.1038/s41467-024-48163-x
- Primary Citation of Related Structures:  
7QI4, 7QI5, 7QI6 - PubMed Abstract: 
The mitoribosome translates mitochondrial mRNAs and regulates energy conversion that is a signature of aerobic life forms. We present a 2.2 Å resolution structure of human mitoribosome together with validated mitoribosomal RNA (rRNA) modifications, including aminoacylated CP-tRNA Val . The structure shows how mitoribosomal proteins stabilise binding of mRNA and tRNA helping to align it in the decoding center, whereas the GDP-bound mS29 stabilizes intersubunit communication. Comparison between different states, with respect to tRNA position, allowed us to characterize a non-canonical L1 stalk, and molecular dynamics simulations revealed how it facilitates tRNA transitions in a way that does not require interactions with rRNA. We also report functionally important polyamines that are depleted when cells are subjected to an antibiotic treatment. The structural, biochemical, and computational data illuminate the principal functional components of the translation mechanism in mitochondria and provide a description of the structure and function of the human mitoribosome.
Organizational Affiliation: 
Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden.