Abstract
In order to test the hypothesis that mitochondrial transcription factor A (mtTFA) regulates mitochondrial transcription in vivo, mtTFA was overexpressed in HeLa cells and imported into isolated rat liver mitochondria. Five hours after transfection with an eukaryotic expression vector, mitochondrial transcripts for cytochrome-c-oxidase subunit I and 12 S rRNA were increased over controls. In the presence of rat liver mitochondria, the 29 kDa mtTFA, generated by in vitro translation, was processed to a 24 kDa protein which was protected from protease digestion. This demonstrates that mtTFA was imported into the matrix. Incorporation of32 P-UTP into mitochondrial transcripts was stimulated following import of mtTFA. We conclude that the intracellular and intramitochondrial concentration of mtTFA, respectively, indeed regulates mitochondrial transcription.
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Montoya, J., Perez-Martos, A., Garstka, H.L. et al. Regulation of mitochondrial transcription by mitochondrial transcription factor A. Mol Cell Biochem 174, 227–230 (1997). https://doi.org/10.1023/A:1006812625445
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DOI: https://doi.org/10.1023/A:1006812625445