Comparisons of the copy number of mtDNA and nuclear DNA in various S. pombe strains. The left panel is the plot of fluorescence versus PCR cycle number. The arrows indicate the median of Ct-values for either mtDNA (mt; in green) or nuclear DNA (nc; in purple). The right panel is the box-plot representing the distribution Ct-values by primer pairs either specific to mtDNA (in green) or nuclear DNA (in purple): the minimal (left-end bar), the first quantile (left side of the box), median (central think bar), the third quantile (right side of the box), and the maximal (right-end bar). The copy number of nuclear DNA in various strains is set to 1 as reference for the copy number of mtDNA. The assays were carried out using total DNA samples extracted from wild type (A), pog1Δ (B), ptp1-1 (C), and ptp2-1 (D) cells as indicated.