Related Experiment Videos
Complete repopulation of mouse mitochondrial DNA-less cells with rat mitochondrial DNA restores mitochondrial
M Yamaoka1, K Isobe, H Shitara
1Institute of Biological Sciences, University of Tsukuba, Ibaraki 305-8572, Japan.
Abstract:
By the fusion of mtDNA-less (rho(0)) cells of Mus musculus domesticus with platelets from different species, mtDNA repopulated cybrids were obtained for finding the mtDNA species that could induce mitochondrial abnormalities. Expression of mitochondrial dysfunction might be expected in these cybrids due to incompatibility between nuclear and mitochondrial genomes from different species. The results showed that mouse rho(0) cells could receive mtDNA from a different mouse species, M. spretus, or even mtDNA from the rat, Rattus norvegicus, and that the introduced rat mtDNA, but not M. spretus mtDNA, caused mitochondrial dysfunction, even though rat mtDNA could restore normal mitochondrial translation in the cybrids. Considering that mitochondrial respiratory complexes consist of nuclear DNA- and mtDNA-coded polypeptides, these observations suggest that the nuclear and mitochondrial interactions required for replication, transcription, and translation of introduced rat mtDNA must be less stringently controlled than those required for formation of normal respiratory complexes. As no procedure for introduction of mutagenized mouse mtDNA into living cells has yet been established, these findings provide important insights into generating mtDNA-knockout mice.
Insights
Introducing foreign mitochondrial DNA (mtDNA) into cells can cause dysfunction. Rat mtDNA, but not mouse mtDNA, induced mitochondrial abnormalities in mouse cells, offering insights for creating mtDNA-knockout mice.
Area of Science:
- Cell Biology
- Genetics
- Mitochondrial Biology
Background:
- Mitochondrial dysfunction can arise from incompatibilities between nuclear and mitochondrial genomes.
- Cybrids (cytoplasmic hybrids) are valuable tools for studying nuclear-mitochondrial interactions.
Purpose of the Study:
- To investigate which species' mitochondrial DNA (mtDNA) can repopulate mtDNA-less cells and induce mitochondrial abnormalities.
- To explore the compatibility of interspecies nuclear-mitochondrial genome interactions.
Main Methods:
- Fusion of mouse (Mus musculus domesticus) mtDNA-less (rho(0)) cells with platelets from different species.
- Repopulation of cybrids with foreign mtDNA.
- Analysis of mitochondrial function and translation in resulting cybrids.
Main Results:
- Mouse rho(0) cells successfully incorporated mtDNA from a different mouse species (M. spretus) and from rats (Rattus norvegicus).
- Introduced rat mtDNA, unlike M. spretus mtDNA, caused significant mitochondrial dysfunction.
- Rat mtDNA restored normal mitochondrial translation despite causing dysfunction.
Conclusions:
- Nuclear and mitochondrial genome interactions for rat mtDNA replication, transcription, and translation are less stringently controlled than those for normal respiratory complex formation.
- These findings provide crucial insights for developing methods to generate mtDNA-knockout mice.