Figure 2.

Mitochondrial DNA Copy number in Mutant Yeast strains – A) Parental strain yeast (BY4741), and mutants deficient in DNA repair (MRE11) and ETC complex 1 (NDI1) function were grown in YPD media with Doxorubicin from 0 to 100 μM for 6 hours; n = 3. BY4741 yeast, cultured in YPG media were included as a positive control for increased mitochondrial abundance. Doxorubicin caused a significant increase in mtDNA content in BY4741 in YPD and YPG and MRE11 mutants; NDE1 mutants blocked this effect. While MRE11 and 4741 YPG yeast have greater mitochondrial DNA abundance than parental, the magnitude of increase upon exposure to doxorubicin is not different between individual strains (data not shown; Dunnett’s p = 0.0014 and 0.0259, respectively) B) Additional mutant strains deficient in TCA cycle components (ACO1, CIT1) show increased mtDNA with doxorubicin exposure, similar to parental YPD, YPG and DNA repair deficient strains. Values are mtDNA copies (COX1) per nuclear DNA (nDNA) copies (ACT1). Error bars are 1 standard deviation. Asterisk(*) indicate significant increase in mtDNA over 0 μM Doxorubicin for that strain; Dunnett’s p < 0.05