Pentamidine acts as a potent and specific inhibitor of mitochondrial translation in yeast, explaining its inhibitory effects on respiratory growth and in vivo splicing of mitochondrial introns.
Does pentamidine inhibit mitochondrial intron splicing and translation in Saccharomyces cerevisiae?
Pentamidine acts as a potent and specific inhibitor of mitochondrial translation in yeast, which explains its inhibitory effects on respiratory growth and mitochondrial intron splicing.
Pentamidine inhibits in vitro splicing of nuclear group I introns from rRNA genes of some pathogenic fungi and is known to inhibit mitochondrial function in yeast. Here we report that pentamidine inhibits the self-splicing of three group I and two group II introns of yeast mitochondria. Comparison of yeast strains with different configurations of mitochondrial introns (12, 5, 4, or 0 introns) revealed that strains with the most introns were the most sensitive to growth inhibition by pentamidine on glycerol medium. Analysis of blots of RNA from yeast strains grown in raffinose medium in the presence or absence of pentamidine revealed that the splicing of seven group I and two group II introns that have intron reading frames was inhibited by the drug to varying extents. Three introns without reading frames were unaffected by the drug in vivo, and two of these were inhibited in vitro, implying that the drug affects splicing by acting directly on RNA in vitro, but on another target in vivo. Because the most sensitive introns in vivo are the ones whose splicing depends on a maturase encoded by the intron reading frames, we tested pentamidine for effects on mitochondrial translation. We found that the drug inhibits mitochondrial but not cytoplasmic translation in cells at concentrations that inhibit mitochondrial intron splicing. Therefore, pentamidine is a potent and specific inhibitor of mitochondrial translation, and this effect explains most or all of its effects on respiratory growth and on in vivo splicing of mitochondrial introns.
Zhang et al. (Sat,) conducted a other in Yeast mitochondrial function. Pentamidine vs. Absence of pentamidine was evaluated on Mitochondrial intron splicing and translation. Pentamidine acts as a potent and specific inhibitor of mitochondrial translation in yeast, explaining its inhibitory effects on respiratory growth and in vivo splicing of mitochondrial introns.