Figure 1.

Experimental set up. (A) Schematic illustration of the experimental system used throughout this study. Pairs of S. cerevisiae strains, either WT or harboring the scc2–4 ts allele, genetically identical in all other aspects except for the presence or absence of the recognition site for the HO enzyme, were grown in YEP media supplemented with 2% raffinose at 21°C, and arrested in G2/M. A temperature raise to 32°C for 30 minutes, renders Scc2 dysfunctional before galactose addition, to induce one DSB or not. After 90 minutes break induction, cells were collected, total RNA prepared, cDNA synthesized and fragmented before hybridization to GeneChip Yeast genome 2.0 Array. (B) Pulse-field gel electrophoresis (PFGE) for verification of pGAL-HO break induction. The arrow points at Chr. VI. (C) FACS profiles of indicated yeast strains at indicated time points.