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Updated: May 30, 2026

Rapid Isolation of the Mitoribosome from HEK Cells
Published on: October 4, 2018
Truncation of the Mrp20 protein reveals new ribosome-assembly subcomplex in mitochondria
Jasvinder Kaur1, Rosemary A Stuart
1Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 53233, USA.
Abstract:
Mitochondrial ribosomal protein 20 (Mrp20) is a component of the yeast mitochondrial large (54S) ribosomal subunit and is homologous to the bacterial L23 protein, located at the ribosomal tunnel exit site. The carboxy-terminal mitochondrial-specific domain of Mrp20 was found to have a crucial role in the assembly of the ribosomes. A new, membrane-bound, ribosomal-assembly subcomplex composed of known tunnel-exit-site proteins, an uncharacterized ribosomal protein, MrpL25, and the mitochondrial peroxiredoxin (Prx), Prx1, accumulates in an mrp20ΔC yeast mutant. Finally, data supporting the idea that the inner mitochondrial membrane acts as a platform for the ribosome assembly process are discussed.
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