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Updated: Feb 24, 2026

Visualization of ATP Synthase Dimers in Mitochondria by Electron Cryo-tomography
Published on: September 14, 2014
Visualization of cytosolic ribosomes on the surface of mitochondria by electron cryo-tomography
Vicki Am Gold1,2,3, Piotr Chroscicki4, Piotr Bragoszewski4
1Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany v.a.m.gold@exeter.ac.uk a.chacinska@cent.uw.edu.pl.
Abstract:
We employed electron cryo-tomography to visualize cytosolic ribosomes on the surface of mitochondria. Translation-arrested ribosomes reveal the clustered organization of the TOM complex, corroborating earlier reports of localized translation. Ribosomes are shown to interact specifically with the TOM complex, and nascent chain binding is crucial for ribosome recruitment and stabilization. Ribosomes are bound to the membrane in discrete clusters, often in the vicinity of the crista junctions. This interaction highlights how protein synthesis may be coupled with transport. Our work provides unique insights into the spatial organization of cytosolic ribosomes on mitochondria.
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