MitoRibo-Tag mice to study the mitochondrial ribosome in vivo
Jakob D. Busch1, Ilian Atanassov2, Eduardo Silva Ramos1, Johanna H. K. Kauppila1, Ana Grönke1, Cristina Remes1, Dusanka Milenkovic1, and Nils-Göran Larsson1,3*
1Department of Mitochondrial Biology, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
2Proteomics Core Facility, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
3Department of Medical Biochemistry and Biophysics, Research Divison of Molecular Metabolism, Karolinska Institutet, Retzius väg 8, 171 65 Solna, Sweden
Mitochondria are essential organelles crucial for converting cellular energy via the oxidative phosphorylation (OXPHOS). Mitochondrial function is tightly linked to the expression of the mitochondrial DNA (mtDNA). Among the many steps regulating mtDNA expression, translation by the mitochondrial ribosome (mitoribosome) is of particular interest since it synthesizes essential protein components of the OXPHOS system. Defective mitochondrial translation leads to severe OXPHOS dysfunction, a process heavily implicated in human pathology and ageing. To purify mitoribosomes from mouse tissues and to study mitoribosomes in vivo we generated “MitoRibo-Tag” knock-in mice expressing a FLAG-tagged variant of the mitoribosomal protein Immature colon carcinoma transcript 1 (ICT1). Our aims are to determine the composition of the mitoribosome from different tissues and to identify putative tissue-specific mitoribosome interacting proteins by label-free quantitative mass spectrometry. A definition of the protein content of the mitoribosome and interacting proteins will contribute to a better understanding of the mitochondrial translation machinery, its assembly and mitochondrial diseases and ageing linked to defective mitochondrial translation.