Aim23 is an yeast mitochondrial translation initiation factor 3 which is unnecessary for protein synthesis
2015 (English)In: Yeast, ISSN 0749-503X, E-ISSN 1097-0061, Vol. 32, no Suppl. 1, S192-S193 p.Article in journal, Meeting abstract (Other academic) Published
Mitochondria are essential organelles of virtually all eukaryotic cells. They have their own genome and are able to transcribe and translate their genetic material. The system of mitochondrial protein synthesis is organized in a manner close to that of prokaryotes. However, mitochondrial DNA contains just a few protein-coded genes (9 in yeast, 13 in humans), so the mitochondrial translation system deals with a limited number of mRNAs. The mitochondrial translation machinery is also somewhat lineage-specific, with various components being gained and lost in different taxonomic groups. The classical bacterial initiation factors (IFs) IF1, IF2 and IF3 are universal in prokaryotes, but only IF2 is universal in mitochondria (mIF2). No IF1 has been identified in mitochondria of any organism. An insertion in mIF2 has been suggested to functionally compensate for the absence of mIF1. Mitochondrial IF3 (mIF3), although known to be present in various eukaryotes, has not been identified for many years in budding yeast Saccharomyces cerevisiae, the model organism for studying mitochondrial translation in vivo. In 2012, we have proven that IF3 does present in yeast mitochondria, and it is Aim23 protein. In the present study, we have characterized the effects of AIM23 gene deletion on yeast mitochondrial function. One could suggest that such a deletion would lead to a complete loss of respiration, translation and other molecular processes in mitochondria. However, this was not the case: the growth of AIM23∆ yeast on clycerol-containing media was suppressed in first 1-2 days only and reached the levels of wild-type in 3-4 days. AIM23∆ cells also were able to respire. Interestingly, we observed a very unusual pattern of mitochondrially-synthesized proteins in the ΔAIM23 strain. The amount of several proteins is decreased in the mutants compared to the wild-type but the amount of some others is increased. We conclude that the yeast cells are able to adapt somehow to the absence of Aim23p.
Place, publisher, year, edition, pages
Wiley-Blackwell, 2015. Vol. 32, no Suppl. 1, S192-S193 p.
Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
IdentifiersURN: urn:nbn:se:umu:diva-109936ISI: 000361466200322OAI: oai:DiVA.org:umu-109936DiVA: diva2:861466
Yeast 2015: 27th International Conference on Yeast Genetics and Molecular Biology, (ICYGMB), Levico Terme, Italy, September 6-12, 2015