Prospects & Overviews
The polypeptide tunnel exit of the mitochondrial ribosome is tailored to meet the specific requirements of the organelle
Article first published online: 21 OCT 2010
Copyright © 2010 WILEY Periodicals, Inc.
Volume 32, Issue 12, pages 1050–1057, December 2010
How to Cite
Gruschke, S. and Ott, M. (2010), The polypeptide tunnel exit of the mitochondrial ribosome is tailored to meet the specific requirements of the organelle. Bioessays, 32: 1050–1057. doi: 10.1002/bies.201000081
- Issue published online: 18 NOV 2010
- Article first published online: 21 OCT 2010
- polypeptide tunnel exit;
- respiratory chain assembly;
The ribosomal polypeptide tunnel exit is the site where a variety of factors interact with newly synthesized proteins to guide them through the early steps of their biogenesis. In mitochondrial ribosomes, this site has been considerably modified in the course of evolution. In contrast to all other translation systems, mitochondrial ribosomes are responsible for the synthesis of only a few hydrophobic membrane proteins that are essential subunits of the mitochondrial respiratory chain. Membrane insertion of these proteins occurs co-translationally and is connected to a sophisticated assembly process that not only includes the assembly of the different subunits but also the acquisition of redox co-factors. Here, we describe how mitochondrial translation is organized in the context of respiratory chain assembly and speculate how alteration of the ribosomal tunnel exit might allow the establishment of a subset of specialized ribosomes that individually organize the early steps in the biogenesis of distinct mitochondrially-encoded proteins.