Figure 6. Genotype Dependence of Telomere Fusions and Transient DNA Damage Response Episodes in Mother Cells.

(A) Semi-quantitative PCR of DNA species resulting from the fusion of a deprotected telomere with an induced double-strand break in genetic backgrounds containing ETI and mrc1^AQ mutant combinations. (B) Same as in (A), but with genetic backgrounds containing ETI and tel1Δ mutations. (C) Two representative profiles of RNR3-GFP peaks occurring in still-dividing individual mother cells. Cell divisions (green diamonds) and RNR3-GFP reporter levels (blue circles) were plotted throughout an individual mother cell’s lifespan. Spline fitting is shown as red lines. (D) Frequencies of RNR3-GFP induction peaks in still-dividing cells such as those shown in (C). p-values < 0.01 (*) and p-values < 0.001 (**) by Fisher’s exact test are indicated. (E) Two representative mother cell profiles shown, as in (C), with cells displaying terminal RNR3-GFP induction peaks. (F) Frequencies of RNR3-GFP induction peaks in terminal mother cells, such as those shown in (E).